Natural Clear Vision Handbook of Ophthalmology

StrongSight Vision

Dr. Benjamin Miller has come out with his new guide called Easy Clear Vision. This guide provides eye exercises called the Easy Clear Vision training that helps to restore perfect 20/20 in 3 weeks time by just spending 15 minutes a day. Glasses and lenses are not the treatment for weak eyesight in fact long use of glasses or lenses can make eyesight even worst. They can create lack of focus in the future. But by using proper holistic approach you can increase the functionality of eye muscles and on other hand you can improve your eyesight as well. This is where you can get help from Dr. Benjamins Easy Clear Vision. So, if you want you know if this program will work for you or not then you have to test it yourself. You will feel secure to know that Dr. Benjamin offering 60-days money back guarantee. You have 60-days to test this program and if you dont get any results then you can return it back to the author and get your money back.

Easy Clear Vision Summary


4.6 stars out of 11 votes

Contents: Ebook, Videos
Author: Dr. Benjamin Miller
Price: $39.00

My Easy Clear Vision Review

Highly Recommended

The author presents a well detailed summery of the major headings. As a professional in this field, I must say that the points shared in this manual are precise.

If you want to purchase this e-book, you are just a click away. Click below and buy Easy Clear Vision for a reduced price without any waste of time.

Download Now

Why Does Amblyopia Treatment Not Always Work

Amblyopia treatment sometimes has no effect and frequently does not improve visual acuity to normal levels. This is often assumed to be because treatment has been started too late to be effective or is unable to be implemented at the prescribed level. While this may often be the case, it is important to realise that subtle ocular and cerebral pathology may also underlie failure to respond to treatment. Optic nerve hypoplasia is easily missed on indirect ophthalmoscopy and should be specifically excluded. Inaccurate refractive correction, which inevitably occurs during periods of emmetropisation, should also be checked for.

The endangered eyesight

In the pre-antibiotic era, i.e., until almost the middle of the 20th century, gonorrhea and ophthalmia neonatorum showed a high prevalence also in industrialized countries 2-7 . In the middle of the 19th century more than 10 of all newborns in Germany developed gonorrheal ophthalmia neonatorum. Clinical courses of gonorrheal ophthalmia neonatorum were quite different in their severity but often caused a huge and irreversible damage to the eyes with a significant impairment of eyesight up to total blindness as final outcome of the disease in more than 5 of the infections. This accounted for 25-40 of cases of blindness in Germany 8-11 . What about silver as a broadly acting antiseptic

How you manage this patient with glaucoma and cataract

Management of glaucoma and cataract Management of glaucoma and cataract Severity of glaucoma Severity of cataract Trabeculectomy first, cataract operation later Alternatively, discuss with patient about advantages of combined cataract operation and trabeculectomy (triple procedure) (see below) Cataract operation first, manage glaucoma conservatively

Visual Rehabilitation in Children with Bilateral Congenital Cataracts

The visual outcome of children with bilateral congenital cataracts has improved dramatically over the past 30 years. For example, while in 1971,10 of the children enrolled in the Western Pennsylvania School for the Blind had been treated for cataracts, the percentage had dropped to 1 by 1991 5 . Nevertheless, as many as one-quarter of children in the US with bilateral infantile cataracts still remain legally blind even after cataract surgery and optical correction. The visual outcome is even worse for children with bilateral infantile cataracts in developing countries, primarily due to a delay in the diagnosis and treatment of their cataracts. For example, Jain 18 reported that in India most children with congenital cataracts do not undergo cataract surgery until they are 1-5 years of age.

Surveys of North American Pediatric Ophthalmologists

In August 1997, the North American members of the American Association of Pediatric Ophthalmology and Strabismus (AAPOS) were surveyed to determine the number of infants they had treated with a unilateral cataract, the frequency of IOL implantation in infants with a unilateral cataract, and the youngest age of a child when they had implanted an IOL 24 . Most respondents (89 ) reported treating at least one infant with a unilateral cataract during the previous year. However,relatively few report Table 6.2. Pros and cons of intraocular lens vs contact lens correction of unilateral infantile aphakia Table 6.2. Pros and cons of intraocular lens vs contact lens correction of unilateral infantile aphakia Contact lenses ed treating many cases (e.g., more than two-thirds reported treating fewer than three cases per year). Only 3.5 of pediatric ophthalmologists had ever implanted an IOL in a child less than 6 months of age. More than one-half (52 ) of the respondents expressed a willingness to...

Excimer Laser in situ Keratomileusis LASIK

Principle Myopia is corrected with preservation of Bowman's layer. A superficial corneal flap (approx. 160 m) is created with a microkeratome. The ker-atome is withdrawn, the flap is reflected, and the exposed underlying corneal stroma is ablated with an excimer laser to correct the myopia. Then the flap is repositioned on the corneal bed and fixed in place by force of its own adhesion. Indication Even severe myopia (up to 10-12 diopters) can be corrected with this method.

Nonperforating Glaucoma Surgery

Nonperforating glaucoma surgery, such as deep sclerectomy or viscocanalostomy, has been performed in infantile glaucoma as a primary and secondary intervention. The efficacy and surgical risks of this surgery are a matter of controversy. While some authors report good success rates of 75 without essential surgical side effects, others emphasize the problems and risks of these procedures in refractory congenital glaucoma leading to a further thinning of the scleral envelope 36,53 . Nonperforating glaucoma surgery has been proposed as a safe and promising approach in episcleral venous pressure glaucoma (e.g., Sturge-Weber-Krabbe syndrome), as surgical risks are minimized and late goniopuncture can produce a late and controlled filtration 36 .

Measuring the twentyfourhour pressure curve Fig 106 This examination is performed to analyze fluctuations of the

H In glaucoma patients maintained on eyedrops, special attention should be given to the time of application. Pressure is measured immediately prior to applying the eyedrops. In this manner, measurements are obtained when the effect of the eyedrops is weakest. Fig. 10.6 The colored dots represent the times of the measurements. The time of the initial application of anti-glaucoma eyedrops is marked (arrow). The time, frequency, and eye of eyedrop application are also identified. Fig. 10.6 The colored dots represent the times of the measurements. The time of the initial application of anti-glaucoma eyedrops is marked (arrow). The time, frequency, and eye of eyedrop application are also identified. 244 10 Glaucoma Tonometric self-examination. 244 10 Glaucoma Tonometric self-examination. any number of measurements obtained under normal everyday conditions. A patient tonometer may be prescribed in applicable cases (such as increased risk of acute glaucoma). However, using the device...

Primary Glaucoma 1031 Primary Open Angle Glaucoma Definition

Primary open angle glaucoma begins in middle-aged and elderly patients with minimal symptoms that progressively worsen. The angle of the anterior chamber characteristically remains open throughout the clinical course of the disorder. Epidemiology Primary open angle glaucoma is by far the most common form of glaucoma and accounts for over 90 of adult glaucomas. The incidence of the disorder significantly increases beyond the age of 40, reaching a peak between the ages of 60 and 70. Its prevalence among 40-year-olds is 0.9 as compared to 4.7 among patients over the age of 50. There appears to be a genetic predisposition for primary open angle glaucoma. Over one- third of glaucoma patients have relatives with the same disorder. Etiology (See also physiology and pathophysiology of aqueous humor circulation) The cause of primary open angle glaucoma is not known, although it is known that drainage of the aqueous humor is impeded. The primary lesion occurs in the neuroretinal tissue of the...

Secondary Glaucomas 271 1041 Secondary Open Angle Glaucoma Definition

The most important forms Pseudoexfoliative glaucoma. This form occurs particularly frequently in Scandinavian countries. Deposits of amorphous acellular material form throughout the anterior chamber and congest the trabecular meshwork. Pigmentary glaucoma. Young myopic men typically are affected. The disorder is characterized by release of pigment granules from the pigmentary epithelium of the iris that congest the trabecular meshwork. Cortisone glaucoma. Thirty-five to forty per cent of the population react to three-week topical or systemic steroid therapy with elevated intraocular pressure. Increased deposits of mucopolysaccharides in the trabecular meshwork presumably increase resistance to outflow this is reversible when the steroids are discontinued. Inflammatory glaucoma. Two mechanisms contribute to the increase in intraocular pressure Phacolytic glaucoma. This is acute glaucoma in eyes with mature or hyper-mature cataracts. Denatured lens protein passes through the intact lens...

Soft Contact Lens for Ocular Drug Delivery

Bandage soft contact lenses made of hydrophilic polymers are widely used to protect eyes with various problems, including recurrent corneal erosions and epithelial defects after corneal transplantation or refractive surgery. Although these bandage soft contact lenses may enhance healing while allowing the eye to remain open, they can be inserted and removed only in the ophthalmologist's office. Additionally, soft contact lenses may harbor pathogens, which can cause ocular infection. The idea of using bandage soft contact lenses to deliver drugs to the cornea was proposed as far back as 1971 by Kaufman (1). In this procedure, the hydrophilic lens was placed on the cornea and the drug was administered topically onto the surface of the lens. The contact lens was thought to act as a carrier vehicle, binding the drug and releasing it slowly, thereby increasing retention of the therapeutic agent in the tear film and at the corneal surface. However, Busin and Spitznas (2) and Matoba and...

Acute Angle Closure Glaucoma

Regimen outlined below is once acute angle closure glaucoma secondary to pupillary block has been established. 5. Recheck the IOP and visual acuity in one hour. If the IOP does not lower and the vision does not improve, we repeat the topical medications and give mannitol l-2g kg IV over 45 minutes (a 500ml bag of mannitol 20 contains lOOg of mannitol). 'From Diagnosis and Therapy of the Glaucoma, 6th ed. St. Louis C.V. Mosby 605-623. 4From Ophthalmology 2005 112 2143-2148. 6. Neuro-Ophthalmology A. AGENTS USED IN NEURO-OPHTHALMOLOGY A. AGENTS USED IN NEURO-OPHTHALMOLOGY 'For protocol, refer to Rhee DJ, Pyfer, MF, eds. The Wills Eye Manual Office and Emergency Room Diagnosis and Treatment of Eye Diseases, 3rd ed. Philadelphia Lippincott Williams & Wilkins, 1999. 'For protocol, refer to Rhee DJ, Pyfer, MF, eds. The Wills Eye Manual Office and Emergency Room Diagnosis and Treatment of Eye Diseases, 3rd ed. Philadelphia Lippincott Williams & Wilkins, 1999.

Iontophoretic Therapies in Ophthalmology

Within the past 10 years, a number of excellent articles chapters have reviewed the application of iontophoresis in therapeutic approaches in ophthalmology (11,12,42-44). Current research in ocular iontophoresis is aimed at resolving the delivery problems associated with newly developed

Advantages and Characteristics of Contact Lenses

Contact lenses are in immediate contact with the cornea. Although they are foreign bodies, most patients adapt to properly fitted contact lenses. Contact lenses differ from eyeglasses in that they correct the refractive error closer to the location of its origin. For this reason, the quality of the optical image viewed through contact lenses is higher than that viewed through eyeglasses. Contact lenses have significantly less influence on the size of the retinal image than does correction with eyeglasses. Lenses do not cloud up in rainy weather or steam, and peripheral distortion is minimized. The cosmetic disadvantage of thick eyeglasses in severe ametropia is also eliminated. Severe anisometropia requires correction with contact lenses for optical reasons, i.e., to minimize aniseikonia. Contact lenses are defined by the following characteristics Diameter of the contact lens. The cornea requires oxygen from the precorneal tear film. To ensure this supply, contact lens materials must...

Contact Lens Complications

Complications have been observed primarily in patients wearing soft contact lenses. These include U Acanthamoeba keratitis is a serious complication affecting wearers of soft contact lenses and often requires penetrating keratoplasty. Severe chronic conjunctivitis This usually makes it impossible to continue wearing contact lenses.

Secondary Open Angle Glaucoma

Particulate or cellular elements present in the trabecu-lar meshwork can cause outflow obstruction. Examples are iatrogenic glaucoma (caused by silicone oil, topical steroids or viscoelastic substances used to coat lens implants), haemolytic glaucoma, lens protein glaucoma, post-traumatic glaucoma and glaucoma in association with tumours (caused by necrotic cells of malignant melanomas and retinoblastomas). The outflow system can also be blocked by melanin pigment granules released from iris stroma or pigment epithelium when the iris is traumatised or becomes atrophic.

Secondary Angle Closure Glaucoma

Primary open angle glaucoma occurs predominantly in the elderly and is caused by an acquired unilateral or bilateral disease of the trabecular meshwork, visible at histopathological examination by hyalinisation of the trabecular meshwork. In secondary angle closure glaucoma, iridotrabecular or iridocorneal contact is present. This is most frequently caused by neovascular glaucoma, in which neovascu-larisation with fibrosis of the iris occurs, for example in retinopathy of prematurity. Other causes are end-stage inflammatory disease, retinal detachment, tumours or trauma.

Tobaccoalcohol amblyopia

A large number of toxic substances can produce impaired vision. Methyl alcohol causes sudden and permanent blindness. Chronic visual loss from optic neuritis develops in malnourished patients with a high tobacco consumption (Tobacco-alcohol amblyopia). The mechanism producing this disorder is uncertain, tobacco contains cyanide which in high dosage can dapnage the optic nerves. Pathology - Reduced visual acuity.

Childhood Glaucomas Definition

Goniotomy And Trabeculotomy

Epidemiology Glaucomas in children occur once every 12000-18000 births and account for about 1 of all glaucomas. Primary congenital glaucoma is an inherited autosomal recessive disorder. It is bilateral in approximately 70 of all cases boys are affected in approximately 70 of all cases and glaucoma manifests itself before the age of six months in approximately 70 of all cases. Today there is widespread public awareness of glaucoma in adults. Unfortunately, this does not yet apply to glaucoma in children. Secondary buphthalmos resulting from acquired eye disorders. Symptoms Classic signs include photophobia, epiphora, corneal opacification, and unilateral or bilateral enlargement of the cornea. These changes may be present from birth (in congenital glaucoma) or may develop shortly after birth or during the first few years of life. Congenital glaucoma. Congenital glaucoma. Special considerations A glaucomatous optic cup in children may well be reversible. Often it will be significantly...

Astigmatism Definition

Irregular Distances Mesuring

Astigmatism is derived from the Greek word stigma (point) and literally means lack of a focal point. The disorder is characterized by a curvature anomaly of the refractive media such that parallel incident light rays do not converge at a point but are drawn apart to form a line. Epidemiology Forty-two per cent of all humans have astigmatism greater than or equal to 0.5 diopters. In approximately 20 , this astigmatism is greater than 1 diopter and requires optical correction. The combined astigmatic components of all of the refractive media comprise the total astigmatism of the eye. These media include Rarely, nonspherical curvature of the retina may also contribute to astigmatism. Classification and causes Astigmatism can be classified as follows External astigmatism astigmatism of the anterior surface of the cornea. Internal astigmatism the sum of the astigmatic components of the other media. Astigmatism can also be classified according to the location of the meridian of greater...

Hyperopia Farsightedness Definition

Manufacture Hypermetropia

In hyperopia, there is a discrepancy between the refractive power and axial length of the eye such that parallel incident light rays converge at a focal point posterior to the retina (Fig. 16.10a). Epidemiology Approximately 20 of persons between the ages of 20 and 30 have refraction exceeding +1 diopters. Most newborns exhibit slight hyperLang, Ophthalmology 2000 Thieme Refraction in hyperopia. Refraction in hyperopia. Fig. 16.10 a The focal point of parallel light rays entering the eye lies posterior to the retina. b Divergent light rays are focused on the retina. The virtual far point lies posterior to the eye (dotted line). c To bring the focal point on to the retina, a farsighted person must accommodate even when gazing into the distance. d Axial hyperopia Refractive power is normal but the globe is too short (more common). e Refractive hyperopia The globe is of normal length but refractive power is insufficient (less common). f A special form of refractive hyperopia is aphakia...

Primary Glaucoma 265 1032 Primary Angle Closure Glaucoma Definition

Etiology (See also physiology and pathophysiology of aqueous humor circulation) Anatomically predisposed eyes with shallow anterior chambers (see Fig. 10.1) pose a relative impediment to the flow of aqueous humor through the pupil. This pupillary block increases the pressure in the posterior chamber (Fig. 10.18a). The pressure displaces the iris anteriorly toward the trabecular meshwork, suddenly blocking the outflow of aqueous humor (angle closure). A typical glaucoma attack occurs unilaterally due to widening of the pupil either in dark surroundings and or under emotional stress (dismay or fear). A typical situation is the evening mystery movie on television. Iatrogenic pharmacologic mydriasis and systemic psychotropic drugs can also trigger a glaucoma attack. H Bear in mind that mydriatic agents entail a risk of triggering a glaucoma attack by widening the pupil. Therefore, it is important to evaluate the depth of the anterior chamber in every patient even prior to a routine fundus...

Forms of cataracts in systemic disease

The typical diabetic cataract is rare in young diabetic patients. Transient metabolic decompensation promotes the occurrence of a typical radial snowflake pattern of cortical opacities (snowflake cataract). Transient hyperopia and myopia can occur. H Diabetic cataract progresses rapidly. Senile cataracts are observed about five times as often in older diabetics as in patients the same age with normal metabolism. These cataracts usually also occur two to three years earlier. Galactosemic cataract. This deep posterior cortical opacity begins after birth. Galactosemia is a rare cause of early cataract in children lacking an enzyme required to metabolize galactose. The newborn receives ample amounts of galactose in the mother's milk. Due a lack of uridyl transferase, or less frequently galactokinase, galactose cannot be metabolized to glucose, and the body becomes inundated with galactose or with galactose and galactose-1-phosphate. If the disorder is diagnosed promptly...

Degenerative Myopia Definition

Myopia Epidemiology

The fundus in degenerative myopia is characterized by abnormal chorioretinal atrophy. Epidemiology Chorioretinal atrophy due to myopia is rare. Pathogenesis The atrophy usually occurs in the presence of severe myopia exceeding minus 6 diopters. The causes include stretching changes in the retina, choroid, and Bruch's membrane due to the elongated globe in axial myopia. Symptoms Loss of visual acuity occurs where there is macular involvement. Differential diagnosis Choroidal scars and angioid streaks (breaks in Bruch's membrane) in pseudoxanthoma elasticum must be excluded by ophthalmoscopy. The diagnosis is unequivocal where myopia is present. Degenerative myopia. Degenerative myopia. Treatment The causes of the disorder cannot be treated. It is important to correct myopia optimally with eyeglasses or contact lenses to avoid fostering progression of the disorder. Subretinal neovascularization outside the fovea or close to its border can be treated by laser photocoagulation. Clinical...

Secondary Angle Closure Glaucoma Definition

Rubeosis Iridis Causes

In secondary angle closure glaucoma as in primary angle closure glaucoma, the increase in intraocular pressure is due to blockage of the trabecular meshwork. However, the primary configuration of the anterior chamber is not the decisive factor. The most important causes Rubeosis iridis. Neovascularization draws the angle of the anterior chamber together like a zipper (neovascular glaucoma). Ischemic retinal disorders such as diabetic retinopathy and retinal vein occlusion can lead to rubeosis iridis with progressive closure of the angle of the anterior chamber. Other forms of retinopathy or intraocular tumors can also cause rubeosis iridis. The prognosis for eyes with neovascular glaucoma is poor (see Fig. 10.20a and b). Neovascular glaucoma secondary angle closure glaucoma with rubeosis iridis. Neovascular glaucoma secondary angle closure glaucoma with rubeosis iridis. Treatment of secondary glaucomas H Medical therapy of secondary glaucomas is usually identical to the treatment of...

Disadvantages of Contact Lenses

Contact lenses exert mechanical and metabolic influences on the cornea. Therefore, they require the constant supervision of an ophthalmologist. Mechanical influences on the cornea can lead to transient changes in refraction. Spectacle blur can result when eyeglasses suddenly no longer provide the proper correction after removing the lens. Contact lenses require careful daily cleaning and disinfection. This is more difficult, time-consuming, and more expensive than eyeglass care and is particular important with soft lenses. Metabolic influences on the cornea The macromolecular mesh of material absorbs proteins, protein breakdown products, low-molecular-weight substances such as medications and disinfectants, and bacteria and fungi. Serious complications can occur where daily care of the contact lenses is inadequate. With their threshold oxygen permeability, soft contact lenses interfere with corneal metabolism. Contact lenses are less suitable for patients with symptoms of...

Treatment and Avoidance of Strabismic Amblyopia

Strict occlusion therapy by eye patching or eyeglass occlusion is the most effective method of avoiding or treating strabismic amblyopia. Primarily the leading eye is patched. 478 17 Ocular Motility and Strabismus Occlusion therapy of amblyopia. - 478 17 Ocular Motility and Strabismus Occlusion therapy of amblyopia. - Fig. 17.11 The leading eye is patched for several hours or days at a time to improve visual acuity in the deviating amblyopic eye. Fig. 17.11 The leading eye is patched for several hours or days at a time to improve visual acuity in the deviating amblyopic eye. Eye patching Severe amblyopia with eccentric fixation requires an eye patch (Fig. 17.11). Eyeglass occlusion (see next section) entails the risk that the child might attempt to circumvent the occlusion of the good eye by looking over the rim of the eyeglasses with the leading eye. This would compromise the effectiveness of occlusion therapy, whose purpose is to train the amblyopic eye. Eyeglass occlusion Mild...

Primary Visual Impairments In Pd

Parkinson Disease Impairments

In the last decades pharmacological studies related to the electroretinogram (ERG) in normal human volunteers and in PD patients have suggested a specific role of dopamine (DA) in retinal processing of visual input.21 3793 99 Going beyond the limitations of human studies, extensive neu-ropharmacological and neurotoxicological studies affecting the dopaminergic system in the monkey and lower vertebrates have led to a more detailed understanding of visual impairment in PD. (For a review, see References 17 and 21.) Various types of DA receptors, broadly classified into D1 and D2 subtypes, are located on different neurons of the retina.59 The dual physiologic action of DA on distal D1 and D2 receptors located on neuronal structures has been studied in detail only in the retina of lower vertebrates with larger neurones.36 However, studying the effects of selective DA receptor ligands on massed elec-trophysiological retinal responses (ERG) in the monkey22 has led to an understanding of the...

Prevention of Inflammatory eye disease in the newborn Information from the Maternity Clinic Leipzig by Crede [22

I am ( ) publishing the following information concerning the prevention of inflammatory eye disease in the newborn ( ) in this Archive because the disease is almost invariably caused by infection during delivery and is therefore directly related to a diseased condition of the female genitals. Responsibility for prevention of the disease must also lie solely with obstetricians and midwives. I shall confine my remarks exclusively to the practical question of prophylaxis. Transmission of the infectious substance from another child with eye disease is inconceivable ( ) inasmuch as every child who is suffering from inflammatory eye disease is moved with its mother to a ward that is entirely separate in all respects from the maternity ward. The possibility of mothers infecting their children, for example through fingers soiled by lochial dis I initially focused on ensuring extensive and effective treatment and cleansing of the diseased vaginas of pregnant and delivering women. But the...

Problems with Contact Lenses

Aroused Female Genital

Etiology These problems occur either with poorly seated rigid contact lenses that rub on the surface of the cornea or from overwearing soft contact lenses. Giant papillae from contact lens incompatibility. Giant papillae from contact lens incompatibility. tissue on the pal-pebral conjunctiva due to contact lens or preservative incompatibility (with tissue on the pal-pebral conjunctiva due to contact lens or preservative incompatibility (with If contact lenses are worn for extended periods of time despite symptoms, severe inflammation, corneal ulceration, and vascularization of the corneal periphery may result. Symptoms Patients find the contact lenses increasingly uncomfortable and notice worsening of their vision. These symptoms are especially pronounced after removing the contact lenses as the lenses mask the defect in the corneal epithelium. Diagnostic considerations The ophthalmologist will detect typical corneal changes after applying fluorescein dye (Fig. 5.11 e)....

Optimal Age for Infantile Cataract Surgery

The optimal age to perform cataract surgery in an infant with an infantile cataract remains controversial. As recently as the 1970s, it was recommended that surgery be deferred until an infant was 3-6 months of age 39 . However, following the pioneering work of Wiesel and Hubel 45 on the plasticity of the visual system during infancy, the trend shifted toward performing cataract surgery at younger and younger ages. The trend climaxed in a case report of a newborn undergoing cataract surgery on the 2nd day of life 14 . Other series have also noted Fig. 6.1. Nuclear cataract in the right eye of a 4-week-old child. The left eye was normal Fig. 6.1. Nuclear cataract in the right eye of a 4-week-old child. The left eye was normal 6.2 Optimal Age for Infantile Cataract Surgery 83 excellent visual outcomes in neonates undergoing cataract surgery during the istweek of life 11 however, an analysis of 45 children with dense unilateral cataracts who underwent cataract surgery found that the...

Contact Lens Solution Hypersensitivity

In any patients in whom sensitivities to ingredients are a strong possibility, the use of preservative-free care systems is strongly recommended. ALL products need to be switched to nonpreserved. Due to the hydrophilic nature of soft contact lenses, whenever these lenses are exposed to products that the patient is sensitive to, the lenses usually need to be replaced in order to solve any related problems. This is not typically true of rigid lenses (since they are not hydrophilic, they do not absorb the solution).

Diagnosis of Infantile Strabismic Amblyopia Preferential Looking Test

Strabismus occurs most frequently in the newborn and infants and must also be treated at this age to minimize the risk of visual impairment. As the examiner cannot rely on patient cooperation at this age, examination techniques requiring minimal patient cooperation are necessary. The preferential looking test can be used for early evaluation of vision beginning at the age of four to six months. This test cannot reliably detect strabismic amblyopia. However, Teller acuity cards (Fig. 17.7) are sufficiently sensitive for early detection of deficits in the presence of defects of the entire visual system.

Uses in Ophthalmology

Antimuscarinic drugs are widely used in ophthalmology to produce mydriasis and cycloplegia. These actions permit an accurate determination of the refractive state of the eye, and the antimuscarinics are also useful in treating specific ocular diseases and for the treatment of patients following iridectomy. Atropine, scopolamine, cyclopentolate (Cyclogyl, AK-Pentolate, and others) and tropicamide (Mydriacyl, Tropicacyl, and others) are among the antimuscarinic drugs used in ophthalmology. All of these agents are tertiary amines that reach the iris and ciliary body after

Congenital cataracts

The management of congenital cataract is difficult. And involves a multidisciplinary team approach. The important issues are And factors that will influence the decisions include The management consists of a thorough history Management of congenital cataracts Indications for cataract extraction Cataract factors (type of cataract, severity of cataract, unilateral or bilateral cataract) Parent factors (motivation of amblyopia correction)

Aphakic Glaucoma

One of the most serious complications that can occur following pediatric cataract surgery is glaucoma. It is usually open angle and has been reported to develop in up to one-third of children after a lensectomy and vitrectomy. Known risk factors for aphakic glaucoma include microcornea, persistent fetal vasculature, and cataract surgery during infancy. Parks and coworkers 35 reported that 54 of the children in their series who developed aphakic glaucoma underwent cataract surgery when they were younger than 2 months of age. Rabiah 36 reported that 37 of children undergoing cataract surgery when 9 months of age or younger developed glaucoma compared to only 6 of children undergoing surgery thereafter.Vishwanath and colleagues 43 noted that 50 of children undergoing bilateral lensectomies during the 1st month of life developed glaucoma in one or both eyes after a 5-year follow-up compared to only 15 of children undergoing cataract surgery when 1 month of age or older. Lundvall and...

Contact Lenses

Contact lenses have been the preferred means of optically correcting aphakia in infants because they more closely simulate the optics of the crystalline lens than do spectacles. During the first 4 years of life, an aphakic infantile eye undergoes a mean decrease in its refractive error of 9-15 D 27,33 . Therefore, the ability to easily change the power of a CL as refractive needs change is a significant advantage. Excellent visual acuities have been obtained in infants with bilateral aphakia using CLs, with up to two-thirds of these children achieving 20 40 or better visual acuity in at least one eye 11,29 . Contact lens compliance is usually good for children with bilateral aphakia and if they become CL intolerant, they can be treated with spectacles. The treatment of monocular aphakia during infancy with CLs has been less successful. In published series, only 8-24 of these eyes achieved 20 40 or better visual acuity and the majority saw 20 200 or worse 29, 34 . These poor visual...


Trabecular Meshwork Blood

Cholinomimetic drugs are useful for treating glaucoma because they can decrease the resistance to the movement of fluid (aqueous humor) out of the eye (Fig. 12.3), thereby reducing the intraocular pressure. It is useful to distinguish between open-angle glaucoma, a chronic condition in which the porosity of the trabecular mesh-work is insufficient to permit the movement of fluid into the canal of Schlemm, and angle-closure glaucoma, an emergency condition in which an abnormal position of the peripheral iris blocks the access of fluid to the tra-becular meshwork. Open-angle glaucoma can be effectively treated with cholinomimetics such as pilocarpine and carbachol, because contraction of the ciliary muscle stretches the trabecular network, increasing its porosity

Contact Lens

Diagnostic and surgical (goniolens, fundus contact lens) What are the therapeutic indications for contact lens Irregular astigmatism keratoconus Therapeutic indications for contact lens Section 3 Corneal and External Eye Diseases What ate the materials used in contact lens 'The ideal material for contact lens should be The current materials include Ideal material for contact lens Current contact lens material High water content extended wear soft contact lens (EWSCL) Low water content daily wear soft contact lens (DWSCL) Tell me about soft contact lens. What are advantages and disadvantages Soft contact lens can be broadly divided into extended wear (EWSCL) or daily wear (DWSCL). They are made of hydrogel, with varying water contents Soft contact lens Poorer VA in eyes with astigmatism What are the pathophysiological changes to the eye with contact lens wear Contact lens wear complications can be divided into blinding and nonblinding. Complications of...


Children suspected of being amblyopic are generally referred for electrodiagnostic testing in order to exclude other pathologies, e. g., when visual acuity has not improved with patching and the fundi are normal or when visual acuity is reduced bilaterally. In amblyopic eyes, pattern visual evoked potentials often show amplitude reduction and or mild to moderate delay 75, 79 that is not due to optical factors 52 . Generally, latency abnormalities in the major positive (P100) component tend to be milder in ani-sometropic than with strabismic amblyopia. Pattern VEPs may also play a useful role in monitoring the effects of patching therapy in amblyopic and fellow eyes 83,87 .

Soft Contact Lenses

The material of the contact lens, such as hydrogel, is soft and pliable. Patients find these lenses significantly more comfortable. The oxygen permeability of the material depends on its water content, which may range from 36 to 85 . The higher the water content, the better the oxygen permeability. However, it is typically lower than that of rigid lenses. The material is more permeable to foreign substances, which can accumulate in it. At 12.5-16 mm, flexible lenses are larger in diameter than rigid lenses. Flexible lenses are often supported by the limbus. The lens is often displaced only a few tenths of a millimeter when the patient blinks. This greatly reduces the circulation of tear film under the lenses. This limits the maximum daily period that patients are able to wear them and requires that they be removed at night to allow regeneration of the cornea. Deviation from this principle is only possible in exceptional cases under the strict supervision of a physician. As the lenses...

Congenital Glaucoma

Glaucoma due to congenital malformation is rare. Associations with systemic disorders like neurofibromatosis 8, 84, 130 and Sturge-Weber syndrome 18, 19 have been described. A malformation of the trabecular mesh-work (goniodysgenesis) or persistence of embryonic tissue in the chamber angle causes an outflow obstruction. The corneoscleral envelope of the infant is distensible, so that a raised intraocular pressure can produce an enlargement of the globe (buphthalmos). A hypercellular trabecular meshwork with hyaloid degeneration is the best visible histopathological finding in those specimens 133 .


Prolonged exposure to ultraviolet light seems to be an important cause of cataracts, a frequent disorder in elderly patients. An extracted lens should be fixed, embedded in paraffin wax and cut in two halves in the antero-posterior direction. Slides can be made by sectioning the cut surface. Cutting the lens before processing can cause artefacts. In cataracts of the elderly degenerated lens fibres form discrete globules and the epithelium covering the inner surface of the anterior lens capsule may extend to the posterior part of the lens. Similar observations are made in cataracts in children 104 .

Senile Cataract

Brunescent Cataract

Epidemiology Senile cataract is by far the most frequent form of cataract, accounting for 90 of all cataracts. About 5 of all 70-year-olds and 10 of all 80-year-olds suffer from a cataract requiring surgery. Ninety percent of all cataracts are senile cataracts. Etiology The precise causes of senile cataract have not been identified. As occurrence is often familial, it is important to obtain a detailed family history. Classification and forms of senile cataracts The classification according to maturity (Table 7.2) follows the degree of visual impairment and the maturity, which earlier was important to determine the time of surgery. We follow a morphologic classification as morphologic aspects such as the hardness and thickness of the nucleus now influence the surgical procedure (Table 7.3) Nuclear cataract. In the fourth decade of life, the pressure of peripheral lens fiber production causes hardening of the entire lens, especially the nucleus. The nucleus takes on a yellowish brown...

Eye Problems

Cataracts In cataracts damage to the protein of the lens of the eye clouds the lens and impairs vision. Oxidation of the lens from exposure to the sun and other sources in the environment is partly responsible for the destruction and nothing can reverse the situation once it has developed. Nutrient deficiencies, selenium, for example, may contribute to cataract formation. Symptoms are blurred or hazy vision, seeing spots, or the feeling of a film over the eye. Vitamin C supplementation may help improve vision. Glutathione, an antioxidant, is found to be especially lacking in cataracts as well as vitamin C, vitamin E, and folic acid. Vitamin A and the carotenoids are important for eye health, lutein a carotenoid is found in the lens. Foods containing these antioxidants are fruits and vegetables, spinach and other green leafy vegetables, broccoli, asparagus, legumes, avocados, oranges, dark berries, plums, and cherries. The herb bilberry is high in antioxidants, 240 to 480 mg of extract...


What are the causes of congenital glaucomas Congenital glaucoma can be classified as primary or secondary. Secondary causes include Classification of congenital glaucoma Congenital glaucoma The classification is exactly the same as for congenital cataracts (page 9) Congenital glaucoma Regional opacity Congenital glaucoma (Haab's straie) Howdo you manage congenital glaucomas The management of congenital glaucoma is difficult. And involves a multidisciplinary team approach. The important issues include Like management of congenital cataracts (page 9), a fairly difficult question to handle Provide precise opening statements to capture spectrum of related problems Management of congenital glaucoma Assessing etiology and inheritance of congenital glaucoma Managing systemic problems of secondary congenital glaucoma Managing associated ocular problems and amblyopia Cataract A xial myopia Goniotomy and trabeculotomy are surgical operations for congenital glaucoma. Treatment options for...

Ocular Examination

Juxtapapillary Hemangioma

The ocular examination should include the best corrected visual acuity and intraocular pressure applana-tion in the primary position and in different vertical and horizontal gazes. A neuro-ophthalmologic examination, including motor and sensory functions, pupillary examination, contrast sensitivity, color vision assessment, confrontation visual fields, and central visual acuity with an Amsler grid should also be done (see Chapter 7). Chorioretinal folds appear as a series of delicate striae, which are most often present in the posterior pole (Figure 6.2). Lines are usually parallel, but rarely they may radiate haphazardly to all directions.5 Although chorioretinal folds are most commonly seen with orbital tumors, they are also seen with muco-celes and other types of cysts and also in cases of orbital injury.6-9 Most chorioretinal folds are without symptoms and do not affect visual acuity. Glaucoma High myopia Hyperopia clusion, juxtapapillary tumors, or cysts. As opposed to choroidal...

Closure Glaucoma

In primary angle closure glaucoma, the aqueous outflow is obstructed by apposition of the iris to the inner surface of the cornea and the trabecular meshwork. The acute form of the disease occurs unilaterally in middle-aged and elderly patients and presents with a rapid and painful rise in intraocular pressure. Both in acute and chronic angle closure glaucoma, three ageing processes seem to cause the closure of the angle shrinkage of the eye, reduction in depth of the anterior chamber and increased size of the lens. most cases not be detected in the tissue without the complete clinical history. Depending upon the rapidity of the rise in pressure, glaucoma causes tissue damage. In a pressure rise to 80 mmHg within 1 or 2 days (acute glaucoma) severe corneal oedema, infarction of the iris, necrosis of the lens and retinal oedema occur. When the pressure rises over a longer period of time more chronic changes can be found. The cornea shows fibrovascular tissue ingrowth at the periphery....

Cataract Definition

A cataract is present when the transparency of the lens is reduced to the point that the patient's vision is impaired. The term cataract comes from the Greek word katarraktes (downrushing waterfall) because earlier it was thought that the cataract was a congealed fluid from the brain that had flowed in front of the lens. General symptoms Development of the cataract and its symptoms is generally an occult process. Patients experience the various symptoms such as seeing only shades of gray, visual impairment, blurred vision, distorted vision, glare or star bursts, monocular diplopia, altered color perception, etc. to varying degrees, and these symptoms will vary with the specific type of cataract (see Table 7.3 and Figs. 7.7 a and b). H Diagnosis of a cataract is generally very unsettling for patients, who immediately associate it with surgery. One should therefore refer only to a cataract when it has been established that surgery is indicated. If the cataract has not progressed to an...

Visual Acuity

Visual acuity, the sharpness of near and distance vision, is tested separately for each eye. One eye is covered with a piece of paper or the palm of the hand placed lightly over the eye. The fingers should not be used to cover the eye because the patient will be able to see between them (Fig. 1.4). The general practitioner or student can perform an approximate test of visual acuity. The patient is first asked to identify certain visual symbols referred to as optotypes (see Fig. 1.2) at a distance of 5 meters or 20 feet (test of distance vision). These visual symbols are designed so that optotypes of a certain size can barely be resolved by the normal eye at a specified distance (this standard distance is specified in meters next to the respective symbol). The eye charts must be clean and well illuminated for the examination. The sharpness of vision measured is expressed as a fraction Examining visual acuity. Examining visual acuity. visual acuity. Normal visual acuity is 5 5 (20 20),...

Rigid Contact Lenses

Corneal Subepithelial Haze

These contact lenses have a stable, nearly unchanging shape. Patients take some time to become used to them and should therefore wear them often. The goal is to achieve the best possible intimacy of fit between the posterior surface of the lens and the anterior surface of the cornea (Fig. 16.19). This allows the contact lens to float on the precorneal tear film. Every time the patient blinks, the lens is displaced superiorly and then returns to its central position. This permits circulation of the tear film. Fit of a rigid contact lens. - Fit of a rigid contact lens. - Rigid contact lenses can be manufactured as spherical lenses and toric lenses. Spherical contact lenses can almost completely compensate for corneal astigmatism of less than 2.5 diopters. This is possible because the space between the posterior surface of the spherical contact lens and the anterior surface of the astigmatic cornea is filled with tear fluid that forms a tear lens. Tear fluid has nearly the same...

Principles of Operation and Technology

Optical Coherence Tomography (OCT) is a new medical diagnostic imaging technology which can perform micron resolution cross-sectional or tomographic imaging in biological tissues 1-4 . The operation of OCT is analogous to ultrasound B-mode imaging or radar except that light is used rather than acoustic or radio waves. OCT is especially suited for diagnostic applications in ophthalmology because of the ease of optical access to the anterior and posterior eye. Imaging techniques which can provide tomographic or cross-sectional images of intraocular structures can yield powerful diagnostic information which is complementary to conventional fundus photography and fluorescein angiography. Techniques such as X-ray computed tomography (CT) and magnetic resonance imaging have been applied for diagnostic imaging in ophthalmology 5-7 . However, these approaches have not been widely used in routine diagnostic applications in ophthalmology because of their limited resolution and preclusive cost...

Ophthalmoscopy 13 111 Ophthalmoscopy

Indirect ophthalmoscopy is usually performed by the ophthalmologist (see p.306) and produces a laterally reversed image of the fundus. Less experienced examiners will prefer direct ophthalmoscopy. Here, the ophthalmoscope is held as close to the patient as possible (Fig. 1.13 see also Figs. 12.4b and c). Refractive errors in the patient's eye and the examiner's eye are corrected by selecting the ophthalmoscope lens required to bring the retina into focus. The examiner sees an erect, 16 power magnified image of the retina. The examination should be performed in a slightly darkened room with the patient's pupils dilated. Students should be able to identify the optic disk. In a normal eye, it is sharply defined structure with vital coloration (i.e., yellowish orange) at the level of the retina and may have a central excavation. The central vein lies lateral to the artery venous diameter is normally 1.5 times greater than arterial diameter. Each vascular structure should be of uniform...

Translation into Practice

If there is any significant refractive error, this should be corrected and the child left in the refractive correction for a period of 16-20 weeks before further treatment is considered. Parents and carers should then be offered an informed choice between occlusion and atropine drops or ointment. Occlusion regimes for strabismic and ani-sometropic types of amblyopia of more than 2 h patching a day, and lasting for more than 6 months,need to be carefully justified.A suggested scheme is shown in the flow diagram (Fig. 3.1).

VEGF and Phase II of ROP

Cleotide or with a molecule to adsorb VEGF (VEGF receptor IgG chimera) significantly decreased the neovascular response in the mouse model of ROP 6,61 , indicating that VEGF is a critical factor in retinal neovascularization. VEGF also has been associated with ocular neo-vascularization by other investigators in other animal models, confirming the central role of VEGF in neovascular eye disease 3,18, 47, 72, 76 . These results correspond to what is seen clinically. VEGF is elevated in the vitreous of patients with retinal neovascularization 2, 4 . VEGF was found in the retina of a patient with ROP in a pattern consistent with mouse results 76 . Based on these and other studies an anti-VEGF aptamer is now available to treat neovas-cularization associated with age-related macular degeneration and is in phase III clinical trials for diabetic retinopathy. Clinical trials are planned for evaluation of treatment of the pro-liferative phase of ROP with anti-VEGF injections.

Conventional Screening

It is crucial to achieve good pupillary dilation in order to allow examination of the retinal periphery in addition to the posterior pole. Recommended eye drops are tropicamide 0.5 together with phenylephrine 2.5 applied two to three times every 5-10 min. As an alternative, custom-made atropine 0.1 eye drops applied also two to three times every 5-10 min may be used, as they provide good mydriasis for about 3 h, thus requiring a less stringent planning of the exact consultation time by the ophthalmologist in charge of the screening. In order to avoid potentially harmful light exposure, the incubator should in this case be covered by a cloth. The nurses are asked to check pupil size, and to repeat the application of cycloplegic agents whenever needed. Immediately prior to the ophthalmic examination, local anesthetic eye drops are instilled (e.g., oxybuprocaine), and a sterile lid speculum for premature infants is gently inserted. The examination is best performed in a darkened room...

Non Proliferafive Diabetic Retinopathy Proliferative Diabetic Retinopathy

Macular edema is a leading cause of treatable vision loss in patients with diabetic retinopathy 1,2 . The high longitudinal resolution of OCT is effective in quantifying macular thickness due to the well-defined differences in optical reflectivity at the anterior and posterior boundaries of the neurosensory retina. Measurements of central foveal thickness with OCT correlate with visual acuity and can provide an indication of the relative contribution of macular edema, as opposed to other factors such as macular capillary non-perfusion, to vision loss 3 . Retinal thickness has been shown to be better correlated with visual acuity than fluorescein leakage in patients with macular edema 4,5 , Sequential OCT tomograms allow the ophthalmologist to accurately track increases or decreases in retinal thickness with more sensitivity than slit-lamp biomicroscopy 3 . Alternatively, multiple OCT tomograms may be obtained at a series of radial or linear sections through the macula to screen for...

Infant Aphakia Treatment Study

The Infant Aphakia Treatment Study (IATS) is a multicenter randomized clinical trial comparing IOL and CL correction for monocular aphakia. Infants will be eligible for the study who are less than 7 months of age and have a visually significant cataract in one eye. Cataract surgery will be performed in a standardized fashion by a surgeon who has been certified for the study. All patients will undergo a lensecto-my, posterior capsulotomy, and anterior vitrectomy. Infants will be randomized at the time of surgery to either IOL implantation or CL correction. Infants randomized to the IOL group will have an IOL implanted into the capsular bag. Spectacles will be used to correct the residual refractive error. Infants randomized to the CL group will be fit with a CL immediately after surgery. All children will be examined by investigators at fixed intervals using standard protocols with the primary outcome being resolution acuity using Teller acuity card, assessed at 12 months of age by a...

Diabetic Retinopathy

Examination of the right eye (D) showed scattered microaneurysms, and dot and blot hemorrhages without clinically significant macular edema or neovascularization. Fluorescein angiography (E) displayed small focal spots of hyper fluorescence with late leakage consistent with microaneurysms. The visual acuity in this eye was 20 25.

Bilateral Simultaneous Surgery

While most pediatric ophthalmologists advocate removing bilateral cataracts as two separate procedures to minimize the risk of bilateral endophthalmitis, others favor bilateral simultaneous surgery in selected patients in order to decrease the number of times general anesthesia will be required, to rehabilitate both eyes simultaneously and to reduce the cost of the procedures 16 . Bilateral simultaneous cataract surgery has also been advocated in adults requiring general anesthesia 17 . In children, it has been proposed that bilateral simultaneous surgery be reserved for children who are at increased risk of complications with general anesthesia (Fig. 6.6) 50 . Extra precautions should be taken to minimize the risk of endophthalmitis such as using a different set of surgical instruments for each eye. Fig. 6.6 a, b. Bilateral nuclear cataracts in a 4-week-old boy with Lowe syndrome and renal dysfunction. Bilateral simultaneous lensectomies were performed to obviate the need for...

Visual Rehabilitation

The visual rehabilitation of children with bilateral congenital cataracts is facilitated by removing both cataracts simultaneously since both eyes are more likely to have the same visual experience. Wright 49 has advocated bilateral patching for up to 2 weeks for infants with both unilateral and bilateral congenital cataracts to prevent amblyopia from developing. By performing simultaneous cataract surgery, the risk of unequal visual input to either eye can be minimized. Bilateral simultaneous cataract surgery may be preferable in infants at increased risk of complications with general anesthesia

Optic Disc Evaluation

Glaucomatous optic disc cupping is seen in the majority of children with infantile glaucoma, as far as limited corneal clarity allows visualization of the optic disc. The degree of optic disc excavation depends on the size of the optic disc, the pressure level, and the duration of increased intraocular pressure. A reversal of optic disc cupping after pressure-reducing surgery can be observed at an early stage of primary congenital glaucoma. This phenomenon of an improved cup disc ratio occurs if intraocular pressure is successfully reduced, especially during the 1st year of life. Between the 2nd and 5thyears of life, unchanged cupping is more frequent following successful glaucoma surgery 57 . In older children, optic disc cupping is considered to be the safest parameter to indicate the stage of glaucomatous damage. Little information is available on the clinical potential of optic disc morphometry by laser scanning tomography in children with congenital glaucoma. Compliance in...

Photorefractive Keratectomy Fig 518d

Principle Tissue is ablated to change the corneal curvature and to achieve a refractive correction. Flattening the corneal curvature corrects myopia, whereas steepening the curvature corrects hyperopia. The amount of tissue removed at different sites can be varied with layer-by-layer excimer laser ablation and the use of apertures. This makes it possible to correct for myopia, by removing more tissue from the center of the cornea, or for hyperopia, by removing more tissue from the periphery. Indications Best results are achieved in correcting myopia of less than 6 diopters. At present stable correction can be achieved in 85 - 95 of all cases of myopia up to 6 diopters, with deviation of 1 diopter from the target within one year. Correction of hyperopia has also been attempted.

Summary for the Clinician

Typical clinical signs of congenital glaucoma In contrast to management in adult glaucoma, several specifications have to be considered in the diagnostic work-up of congenital glaucoma. However, if onset of glaucoma occurs after 3 years of age the typical stretching of the globe is usually absent Despite manifest congenital glaucoma the intraocular pressure may be normal under deep general anesthesia. Several sources of error may confuse intraocular pressure measurements in buphthalmic eyes Glaucomatous excavation of the optic disc is usually present, but evaluation of the optic disc is often impossible owing to corneal opacities. Glaucomatous excavation can be reversible in very young children following IOP control Skiascopy, or another method of determining the objective ocular refraction, should be performed regularly, because refractive problems such as ametropia and ani-sometropia are very common in buph-thalmic eyes and may also contribute to amblyopia

Central Serous Chorioretinopathy

The patient returned for a follow-up visit six weeks later with no improvement in visual acuity. Slit-lamp examination revealed that the serous elevation had decreased since the previous visit. A repeat OCT tomogram (D) taken at this time confirmed the decrease in subretinal fluid accumulation. The height of the detachment was measured to be 120 urn directly beneath the fovea. On follow-up examination another two months later, the patient noted a decrease in the size of the scotoma in his left eye, and his visual acuity had returned to 20 20, No remaining sub-retinal fluid was observed on indirect ophthalmoscopy. A third horizontal OCT image (E) taken through the fovea showed that the detachment had completely resolved directly beneath the fovea. However, a residual region of fluid accumulation remained temporal to the fovea.

Use of Antifibrotic Agents

The intraoperative use of mitomycin C (MMC) during trabeculectomy and its long-term effectiveness in congenital glaucoma have been investigated in several retrospective studies, with the general conclusion that there are significantly more complications associated with the use of MMC in infantile glaucomas 38, 48 . Incidence and frequency of postoperative complications (thin avascular filtering blebs, choroidal detachment, wound leakage) following combined trabeculotomy-trabeculectomy were found to depend on the concentration of mitomycin C used (o.2mg ml vs o.4mg ml) 1 . A higher concentration of mitomycin C (o.5mg ml) administered intraoperatively for 3-4 min during trabeculectomy produced a considerable rate of late bleb-related infection (17 ) at an average follow-up of 28 months 50 . The success rate in this study was 59 after 3 years for primary and secondary pediatric glaucomas.

Cyclodestructive Procedures

Over the last decade, laser destruction of the ciliary body has gradually replaced cryode-struction as the cyclodestructive procedure of choice in refractory congenital glaucoma, since the ocular side effects are less severe after laser surgery. Owing to the anomalous limbal anatomy of buphthalmic eyes, it is feasible to perform transscleral laser coagulation of the ciliary body with the aid of transscleral illumination in order to determine the exact localization of the ciliary body and to identify areas of previous destruction. The most frequent method used to destroy the nonpigmented ciliary body in pediatric glaucoma is contact-diode transscleral cyclo-photocoagulation (TSCPC). Most retrospective studies reveal that this laser procedure is generally applied more than once in each patient. Although IOP reduction can be achieved by TSCPC after year, the success rates are not always completely convincing, ranging between 27 and 79 5, 28,35 depending on the success criteria used and...

Surgical Iridectomy Laser Iridotomy

Iridectomy is the treatment of choice in certain cases of angle-closure glaucoma. Pupillary block that should be treated by iridectomy may be present in spherophakia (e.g., Weill-March-esani syndrome), in uveitic glaucoma with 360 posterior synechiae, and in nanophthalmic eyes. Pupillary block mechanisms due to lens dislocation (e.g., in Marfan's syndrome) should be primarily treated by lens extraction rather than by iridectomy. Other reasons for angle-closure glaucoma in children may be irido-ciliary cysts, hyperplastic primary vitreous, and retinopathy of prematurity 47 .

Intraoperative Complications

Ophthalmic surgeons, this procedure remains technically challenging in congenital glaucoma, as the limbal anatomy is usually distorted and the sclera extraordinarily thin. This can lead to inadvertent scleral perforation during preparation of the scleral flap. Another potential risk can be prolapse of the vitreous or ciliary body through the peripheral iridectomy into the tra-beculectomy opening, especially in the case of a primarily dislocated lens. Typical intraoperative problems of goniotomy may be touching of the lens, with subsequent cataract formation and leaking corneal incisions. Intraoperative complications of cyclodialysis ab-interno also include massive hemorrhage.

Optic Disk Ophthalmoscopy

Stereoscopic examination of the optic disk through a slit-lamp biomicroscope fitted with a contact lens provides a three-dimensional image. The optic cup may be examined stereoscopically with the pupil dilated. H The optic nerve is the eye's glaucoma memory. Evaluating this structure will tell the examiner whether damage from glaucoma is present and how far advanced it is. Normal optic cup (Fig. 10.8) The normal anatomy can vary widely. Large normal optic cups are nearly always round and differ from the vertical elongation of the optic cup seen in eyes with glaucoma. Glaucomatous changes in the optic nerve Glaucoma produces typical changes in the shape of the optic cup. Progressive destruction of nerve fibers, fibrous and vascular tissue, and glial tissue will be observable. This tissue atrophy leads to an increase in the size of the optic cup and to pale discoloration of the optic disk (Fig. 10.10). H Progressive glaucomatous changes in the optic disk are closely associated with...

Diagnostic considerations Measurement of intraocular pressure Elevated intraocular pressure in a routine ophthalmic

The angle of the anterior chamber is open and appears as normal as the angle in patients without glaucoma. Ophthalmoscopy. Examination of the optic nerve reveals whether glaucomatous cupping has already occurred and how far advanced the glaucoma is. Where the optic disk and visual field are normal, ophthalmoscopic examination of the posterior pole under green light may reveal fascicular nerve fiber defects as early abnormal findings. Perimetry. Noise field perimetry is suitable as a screening test as it makes the patient aware of scotomas and makes it possible to detect and describe them. The patient is shown a flickering monitor displaying what resembles image noise on a television set. The patient will not see the flickering points in the region of the scotoma. After this test, the defect should be quantified by more specific methods. Automatic grid perimetry is suitable for the early stages of glaucoma. Special programs (such as the G1 program on the Octopus perimeter...

Macular Degeneration

A 52-year-old man with degenerative myopia experienced a decline in the vision in his right eye two years prior to evaluation. At that time, a choroidal neovascular lesion was diagnosed and treatment was not performed. On the present examination (A), the visual acuity in his right eye was 20 125, and there was a pigmented chorioretinal lesion in the center of the macula. A region of chorioretinal atrophy was noted immediately inferior to the fovea.

Capillary Hemangioma

It usually is clinically apparent at birth or within the first few weeks after birth. It tends to cause progressive proptosis during the first few months of life and then it becomes stable and slowly regresses. Orbital imaging studies show a diffuse, poorly circumscribed, orbital mass that enhances with contrast material. The best management is refraction and treatment of any induced amblyopia with patching of the opposite eye. Local injection of corticosteroids or oral corticosteroids can hasten the regression of the mass and minimize the complications.

Pattern Electroretinography

The pattern electroretinogram (PERG) is the response of central retina and is usually measured using a reversing black and white checkerboard. It is important that there is no luminance change during pattern reversal. It allows both a measure of central retinal function and, in relation to its origins, an evaluation of retinal ganglion cell function. It is thus of great value in the electrophysiological differentiation between macular dysfunction and generalised retinal dysfunction or optic nerve dysfunction in the older child with visual acuity loss (see 40 for a comprehensive review). It is important to preserve the optics of the eye for PERG recording, which requires non-contact lens electrodes in contact with the cornea or bulbar conjunctiva to preserve the optics of the eye, and no mydriasis. The gold foil, the DTL and the H-K loop electrode are all suitable. Ipsilateral outer canthus reference electrodes are mandatory there is contamination from the cortically generated VEP if...

Macular Degenera t on

Follow-up slit-lamp examination (A) two weeks later demonstrated persistence of the neovascular membrane in the macula. A lesion in the central macula which was described as either a hemorrhagic pigment epithelial detachment or a subretinal thrombus was observed, with surrounding subretinal fluid, exudate, and trace hemorrhage. The patients visual acuity had deteriorated to 20 400. Fluorescein angiography (B) displayed a hypofluorescent lesion in the central macula with mild hyperfluorescence along the inferonasal rim. The entire rim of the lesion became hy per fluorescent as the angiogram progressed, and well-defined pooling of dye was observed in the entire region in the late phases.

Leber Congenital Amaurosis

Leber congenital amaurosis (LCA) accounts for approximately 15 of congenital blindness. This largely recessively inherited disorder manifests with signs of very poor visual function and roving eye movements or nystagmus. Eye-poking or eye-rubbing, the oculodigital sign, may be present and may eventually lead to sunken orbits, cataract and keratoconus. The majority of patients have normal fundi at presentation, but disc pallor, vessel attenuation and pigmentary changes may follow. The ERG is typically severely reduced or undetectable from early infancy (Fig. 9.2B).

Cone Dysfunction Syndromes

Rod monochromatism is an autosomal recessive disorder characterised by poor vision from birth, nystagmus and photophobia and is consequent upon mutations in CNGA3 or CNGB3 62 . Patients usually attain acuities of about 6 60 and have absent colour vision. Most patients are hyperopic. The fundus is usually normal, although some granularity of the central macula may develop with time. The ERG reveals an absent or severely reduced 30-Hz flicker response, but good rod ERGs following even a limited period of dark adaptation (Fig. 9.2 C). Minor reduction in maximum ERG a-wave may reflect the absence of the cone contribution from this mixed response. S-cone monochromatism is usually an X-linked disorder in which there is absent L- and M- cone function. The presentation in infancy is similar to rod monochromatism but the visual acuity is better (typically between 6 24 and 6 60) and the refractive error is usually myopic. Spectral sensitivity measurement can distinguish S-cone monochromatism...

Central Serous Chorioretinopathy Definition

Symptoms Patients present with a loss of visual acuity, a relative central scotoma (dark spot), image distortion (metamorphopsia), or perception of objects as larger or smaller than they are (macropsia or micropsia). Diagnostic considerations Ophthalmoscopy will reveal a serous retinal detachment, usually at the macula. In chronic cases, a fine brown and white pigment epithelial scar will develop at the site of the fluid effusion. Swelling in the central retina shortens the visual axis and produces hyperopia. The site of fluid effusion can be identified during the active phase with the aid of fluorescein angiography (Fig. 12.26a and b). Clinical course and prognosis The prognosis is usually good. However, recurrences or chronic forms can lead to a permanent loss of visual acuity.

Optic Nerve Hypoplasia

Infants with severe bilateral optic nerve hypoplasia (ONH) usually present with nystagmus and poor vision. Although these patients have small pale optic discs, the optic nerve abnormality may easily be missed when examining a small infant with nystagmus. Electrophysiological testing is extremely useful in detecting visual pathway abnormalities and may prompt review of the optic disc appearance. It is important to make a specific diagnosis, as ONH may be associated with endocrine abnormalities, particularly growth hormone deficiency, which need treatment. Pattern and Flash VEPs show varying degrees of attenuation and delay 2,49 and may be undetectable in severe cases. ERGs are normal and may be of high amplitude 13,48 . Patients with cone or cone-rod dystrophy typically present with progressive loss in visual acuity, abnormal colour vision, photophobia and often nystagmus Severe visual impairment and roving eye movements or nystagmus from birth or early infancy Poor vision, nystagmus,...

Best Vitelliform Macular Dystrophy

Best vitelliform macular dystrophy is an autosomal dominant disorder caused by mutations in VMD2, which encodes bestrophin 70 . Best disease usually has a childhood or teenage onset and in the early stages is typically characterised by a well-circumscribed vitelliform macular lesion, resulting from accumulation of lipofuscin at the level of the RPE. Visual acuity is usually normal until the subsequent vitelliruptive stage, resulting in disruption of overlying photoreceptors and eventual macular atrophy. The electro-physiology in Best disease is characteristic. Full-field ERGs are normal but the electro-ocu-logram (EOG) light rise is severely reduced or undetectable, in keeping with severe generalised dysfunction affecting the RPE-photore-ceptor interface. The EOG is abnormal during the asymptomatic previtelliform stage. Pattern ERGs are typically normal until the vitellirup-tive stage, when there is visual acuity loss and, at that stage, PERG reduction. Patients younger than about 6...

Retinitis Pigmentosa Definition

This term is used to refer to a heterogeneous group of retinal disorders that lead to progressive loss of visual acuity, visual field defects, and night blindness. The name retinitis pigmentosa comes from the pigment deposits that characterize these disorders. In their classic form (see findings and diagnostic considerations) of such disorders, these deposits progress from the periphery to the center of the retina.

Linked Juvenile Retinoschisis

Although, strictly, full-field ERG abnormalities imply generalised retinal dysfunction, X-linked retinoschisis (XLRS) may be referred to as a macular dystrophy. Patients typically present in the 1st or 2nd decade with reduced visual acuity, and macular abnormalities are present in most cases. Classically, these have a spoke wheel appearance due to the presence of foveal micro-cysts. The retinal cleavage may be revealed by optical coherence tomography 80 . With time, these radial cystic changes may give way to nonspecific macular atrophy. Peripheral schisis lesions are only present in 50 of patients, mostly in the infero-temporal quadrant. In older patients with nonspecific macular atrophy, but no peripheral schisis, the diagnosis may not be obvious and electrophysiology may be instrumental in making the diagnosis or suggesting a candidate gene. An electronegative maximal ERG is typically present (Fig.9.2D), although the degree of abnormality can vary and in rare cases b-wave...

Differential Diagnosis

It is now recognised that LCA represents the most severe end of the spectrum of infantile onset retinal dystrophies. Some genes originally described as causing LCA have since been shown to have a less severe clinical pheno-type-with less nystagmus, normal pupil reactions, and better vision despite an absent ERG

Genotype Phenotype Correlations

The findings of high hyperopia ( +7 DS), severe photophobia, poor vision of count fingers (CF) or light perception (LP) in addition to the presence of early peripheral and macular degeneration with bone spicule pigments in the periphery, disc pallor and vessel attenuation has been suggested by Perrault et al. to be pathognomonic of the GUCY-2D mutation 103 . Other groups have, however, reported LCA patients with GUCY-2D mutations who have no significant photophobia, better visual acuity (20 200), and mild to moderate hyperopia 25 .

Chorioretinal Inflammatory Diseases

A 24-year-old man with HIV retinopathy noticed decreasing visual acuity in his left eye. On examination, his visual acuity was 20 30. Slit-lamp biomicroscopy (A) revealed multiple cotton wool spots distributed along the inferotemporal and superotemporal arcades, mild edema of the optic disc attributed to n euro retinitis, and a star pattern of exudate directly in the fovea.

Clinical Features and Electrophysiology

CSNB is characterised by night blindness, variable visual loss and usually normal fundi, although some patients have pale or tilted optic discs. CSNB may be inherited as an AD, AR or XL disorder with XL inheritance being most common. Patients with AD CSNB usually present with nyctalopia and have normal visual acuity 36 whereas in XL and AR, CSNB presentation is usually in infancy with nystagmus, moderate to high myopia, strabismus, reduced central vision, and in some cases paradoxical pupil responses (pupillary dilatation to bright

Management of Stationary Retinal Dysfunction Syndromes

The stationary retinal dysfunction syndromes are currently not amenable to any form of treatment. However, all patients and their families benefit from genetic counselling, educational and occupational advice, and supportive measures such as the provision of appropriate spectacle correction and low vision aids, and the treatment of concurrent ocular problems such as myopia or cataracts. Photophobia is often a prominent symptom in the cone disorders and therefore tinted spectacles or contact lenses may be beneficial to patients,in terms of both improved comfort and vision. For example, red contact lenses have

Ehlers Danlos Syndrome

With the autosomal recessive type VI variant of the Ehlers-Danlos syndromes (EDS VI), also classified as the kyphoscoliotic type, are clinically characterized by neonatal kyphoscoliosis, generalized joint laxity,skin fragility, and severe muscle hypotonia at birth. EDS VI results from mutations in the lysyl hydroxylase 1 gene (PLODi) causing a deficiency of lysyl hydroxylase. This enzyme hy-droxylates specific lysine residues in the collagen molecule to form hydroxylysines, important in collagen cross-linking, which gives collagen its tensile strength. Ocular involvement in EDS VI includes myopia, thin sclera, microcornea and rheg-matogenous retinal detachment. Retinal detachment repair may be complicated by susceptibility to suprachoroidal haemorrhage because of vascular fragility.

Wagner Vitreoretinopathy

Wagner described 13 affected individuals in a three-generation pedigree with autosomal dominant inheritance, low myopia, fluid vitreous, cortical cataract, and variably affected dark adaptation. The cardinal features noted were the complete absence of the normal vitreal scaffolding and preretinal, equatorial, and avascular greyish-white membranes. Rhegmatogenous retinal detachment was not originally reported. There are no associated systemic features. Twenty-eight members of the original pedigree have been examined 16 and four patients had a history of a rhegmatogenous retinal detachment in one eye at a median age of 20 years and 55 of patients older than 45 years had peripheral tractional retinal detachments. Chorioretinal atrophy and cataract increased with the patients' age. Several families with Wagner syndrome, including the original pedigree, have been linked to 5q14.3.

Prophylaxis in Rhegmatogenous Retinal Detachment

Factors traditionally associated with retinal detachment include refractive error, a positive family history, visible lattice retinopathy and fellow eye involvement, but the nature of these associations is poorly understood. The prevalence of myopia varies enormously and even in Stickler syndrome up to 20 patients may have no significant refractive error. Many patients with retinal detachment have none of the accepted risk features such as lattice retinopathy and, in those that do, retinal tear formation frequently occurs in areas remote from such pathology, so that the associations with accepted risk factors requires refinement.

Magnifying Vision Aids

The reduction in central corrected visual acuity as a result of destruction of the fovea with a central scotoma requires magnifying vision aids. However, magnification is always associated with a reduction in the size of the visual field. As a result, these vision aids require patience, adaptation, motivation, and dexterity. Cooperation between ophthalmologist and optician is often helpful. The following systems are available in order of magnification. Example Eyeglasses with a 10 diopter near-field correction magnify the image two and one-half powers. However, the object must be brought to within 10 cm of the eye.

Agent and Epidemiology

The rubella virus is a member of the Toga-viridae family in which the virus contains a single-stranded RNA surrounded by a lipid envelope, or toga. The congenital form was first described by an ophthalmologist, Sir Norman McAlister Gregg in 1941. He practiced in Sydney, Australia, where he reported several cases of congenital cataracts, congenital heart disease, and deafness associated with rubell a during pregnancy 31 . This represents the first demonstration of teratogenicity secondary to a viral agent. Rubella has worldwide distribution, and is a major cause of blindness in developing countries. However, it is rare in the United States since its epidemic pattern was interrupted in 1969 by widespread use of the vaccine 3 .

Eye Manifestations

In the periphery (20 eyes) (Fig. 13.6). Macular chorioretinal scars were the second most prevalent findings (ten eyes) and in five of these eyes there was also peripheral scarring. Optic atrophy was seen bilaterally in three patients,but always in association with extensive chorioretinal scars and therefore it may be secondary to the scarring. Nystagmus was present in three cases, but that along with esotropia and exotropia, each in one patient, is probably secondary to the visual loss due to the chorioretinal scarring. The cataract and microphthalmia were seen in the same eye.

Testing Binocular Vision

Bagolini test This test uses flat lenses with fine parallel striations. The stria-tions spread light from a point source into a strip. The lenses are mounted in the examination eyeglasses in such a manner that the strips of light form a diagonal cross in patients with intact binocular vision. The patient is asked to

Therapy of Concomitant Strabismus

The ophthalmologist determines whether the cause of the strabismus may be treated with eyeglasses (such as hyperopia). 2. If the strabismus cannot be fully corrected with eyeglasses, the next step in treatment (parallel to prescribing eyeglasses) is to minimize the risk of amblyopia by occlusion therapy. 3. Once the occlusion therapy has produced sufficient visual acuity in both eyes, the alignment of one or both eyes is corrected by surgery. Late strabismus with normal sensory development is an exception to this rule (for further information, see Surgery). The alignment correction is required for normal binocular vision and has the added benefit of cosmetic improvement.

Neglect and Noncompliance

Although this form of child abuse is perhaps the most common, it is also the most difficult to identify and manage. Although neglect may manifest as a more dramatic physical failure to thrive (psychosocial growth retardation), the ophthalmologist is more often confronted with parents and other caregivers who fail to attend scheduled appointments or adhere to prescribed treatment regimens such as occlusion therapy for amblyopia. Apparent noncompli-ance may result from confounding factors that significantly impair a parent's ability to comply poverty leading to an inability to afford care, access to care (transportation, insurance coverage), lack of child care for siblings, inability to leave work, misunderstanding of the instructions or the seriousness of the eye disease, and others. When concerned about possible abusive neglect and noncompliance, the ophthalmologist should first explore such factors, perhaps with the help of a social worker or other support personnel. Absent such...

Injuries Due to Physical Agents

Symptoms and diagnostic considerations Symptoms typically manifest themselves after a latency period of six to eight hours. This causes patients to seek the aid of an ophthalmologist or eye clinic in the middle of the night, complaining of acute blindness accompanied by pain, photophobia, epiphora, and an intolerable foreign-body sensation. Often severe blepharospasm will be present. Slit-lamp examination will require administration of a topical anesthetic. This examination will reveal epithelial edema and superficial punctate keratitis or erosion in the palpebral fissure under fluorescein dye (see Fig. 18.5).

Vitreous Detachment Definition

Martegiani Ring

Epidemiology Six percent of patients between the ages of 54 and 65 and 65 of all patients between the ages of 65 and 85 have posterior vitreous detachment. Patients with axial myopia have a predisposition to early vitreous detachment. Presumably the vitreous body collapses earlier in these patients because it must fill a longer eye with a larger volume.

Arteriosclerotic Anterior Ischemic Optic Neuropathy Definition

Subsidence Definition

Epidemiology Arteriosclerotic AION is a common cause of sudden loss of visual acuity. The greatest incidence of this disorder is between the ages of 60 and 70. In contrast to arteritic AION, it can also occur in adults below the age of 60. Symptoms Patients report a sudden unilateral loss of visual acuity. This is due to segmental or complete infarction of the anterior portion of the optic nerve. Severity is variable. The patient may present with wedge-shaped visual field defects (Fig. 13.12b) or horizontal visual field defects that correlate with segmental nerve fiber edemas. However, severe concentric defects progressing to total blindness can also occur. Vision may or not be impaired. An afferent pupillary defect is always present.

Noninfectious Conjunctivitis

Conjunctival Chemosis

Acute conjunctivitis should be distinguished from the group of allergic forms of conjunctivitis, which can be due to seasonal influences and often affect the nasal mucosa. Examples include allergic conjunctivitis (hay fever Fig.4.17) and vernal conjunctivitis. In giant papillary conjunctivitis, the inflammation is triggered by a foreign body (hard or soft contact lenses. There may also be an additional chronic microbial irritation such microbial contamination of contact lenses. Phlyctenular keratoconjunctivitis is a delayed allergic reaction to microbial proteins or toxins (staphylococcal inflammation). This disease occurs frequently in atopic individuals and is promoted by poor hygiene. The cardinal rule in allergic conjunctivitis is to avoid the causative agent. Desensitization should be performed as a prophylactic measure by a dermatologist or allergist. Long-term treatment includes cromoglycic acid eyedrops to prevent mast cell degranulation. Treatment of acute allergic con-...

More Products

Rediscover Your Vision