Dry Eye Causes and Treatment
Ophthalmic lubricating ointments are similar to artificial tears in their makeup. In addition, ointments contain emollients such as petrolatum, mineral oil, and lanolin. Applied as a small ribbon to the inferior cul-de-sac, these products dissolve at ocular surface temperature, spread with the tear film, and lubricate and protect the tissues. The increased contact time and viscosity of ophthalmic lubricating ointments make them very useful in the treatment of severe dry eye or in cases of exposure secondary to nocturnal lagophthalmos (a condition where the lids do not entirely close during sleep). Though ointments have advantages, their major drawback, like all ophthalmic ointments, is the transient blurring of vision. Ointments are, thus, used primarily at night, unless the dry eye is significant enough to warrant otherwise. A list of selected lubricating ointments is provided in Table 5-4.
In the past, it has seemed reasonable for pharmacovigilance experts to reduce their work load and avoid having to see multitudes of reports of more trivial or well-known adverse reactions, but this has both health and methodological consequences. It is often forgotten that serious adverse and unexpected'' reactions can be preceded by less serious phenomena. The best known is the xerophthalmia related to practolol being the harbinger of sclerosing peritonitis. Also, the persistent reporting of a well-known (to experts) adverse reaction-product combination can be important since it may indicate that practitioners in the field are concerned about it for some practical reason. The reasons may be that they see the reaction more frequently than they think they should, that there is something unusual about the duration or severity, or that there are systematic errors associated with the use of the product which
Many physiological factors of normal and diseased eyes affect the performance of the delivery system. The rate of tear turnover and composition of the preocular tear film changes in various pathological conditions. The vehicles used in the formulation may also contribute to direct stimulation of the epithelial layers of the cornea or conujunctiva and cause release of enzymes, glycoproteins, or immunological factors. In pathologies involving mucus-secreting epithelial cells, hypersecretion is more common than hyposecretion. Mucus hyposecretion results in disruption of the tear film and dry spot formation. An excess of mucus occurs in a number of disease states such as neuroparaly tickeratitis and keratoconjunctivitis sicca. Under these conditions, the degree of sulfation of the mucin layer is also known to increase (7). Blinking mixes the secretions and removes tear film debris. In addition, the dosage form location will contribute to the composition and rate of tear secretion in a...
The most frequent adverse reactions to trifluridine administration are transient burning or stinging and palpebral edema. Other adverse reactions include superficial punctate keratopathy, epithelial keratopathy, hypersensitivity, stromal edema, irritation, keratitis sicca, hyperemia, and increased intraocular pressure.
Despite shielding, tear film insufficiency and subsequent dry eye syndrome frequently occur after radiation therapy for orbital lymphoma. Significant radiation vasculopathy of the retina and optic nerve does not usually occur with the usual total dose used for orbital lymphoma ( 50 Gy).28
Symptoms The onset of this generally painless disorder is usually between the ages of 20 and 45. Patients complain of reddened dry eyes with a sensation of pressure (symptoms of keratoconjunctivitis sicca) and of cosmetic problems. Ocular motility is also limited, and patients may experience double vision.
Pathogenesis and individual stages of diabetic retinopathy Diabetes mel-litus can lead to changes in almost every ocular tissue. These include symptoms of keratoconjunctivitis sicca, xanthelasma, mycotic orbital infections, transitory refractory changes, cataract, glaucoma, neuropathy of the optic nerve, oculomotor palsy. However, 90 of all visual impairments in diabetic patients are caused by diabetic retinopathy. The most common international nomenclature used to describe the various changes in diabetic retinopathy
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 keratoconjunctivitis sicca.
62 3 Lacrimal System 3.4 Lacrimal System Dysfunction 3.4.1 Keratoconjunctivitis Sicca Definition Noninfectious keratopathy characterized by reduced moistening of the conjunctiva and cornea (dry eyes). Epidemiology Keratoconjunctivitis sicca as a result of dry eyes is one of the most common eye problems between the ages of 40 and 50. As a result of hormonal changes in menopause, women are far more frequently affected (86 ) than men. There are also indications that keratoconjunctivitis sicca is more prevalent in regions with higher levels of environmental pollution. Etiology Keratoconjunctivitis sicca results from dry eyes, which may be due to one of two causes Dry eyes can represent a disorder in and of itself. Diagnostic considerations Often there is a discrepancy between the minimal clinical findings that the ophthalmologist can establish and the intense symptoms reported by the patient. Results from Schirmer tear testing usually show reductions of the watery component of tears, and...
Symptoms and clinical picture Loss of the eyelashes and eyelid pigmentation accompanied by blepharitis are typical symptoms. A dry eye is a sign of damage to the conjunctival epithelium (loss of the goblet cells). Loss of visual acuity due to a radiation cataract is usually observed within one or two years of irradiation. Radiation retinopathy in the form of ischemic retinopathy with bleeding, cotton-wool spots, vascular occlusion, and retinal neovasculariza-tion usually occurs within months of irradiation.
Clearly all persons who do considerable writing do not develop writer's cramp. Likely, analogously, many patients who have blepharospasm have a history of eye symptoms, such as dry eye, before the onset of the dystonia. Patients with focal laryngeal dystonia, spasmodic dyspho-nia, often have a history of a sore throat. Hence, the most likely scenario is that, like most diseases, focal dystonias are products of a genetic background and an environmental insult. That is, for example, writer's cramp develops with excessive writing only in those persons who are genetically predisposed. There is evidence that there is a genetic influence in the focal dystonias.
This rare clinical picture characterized by intermittent unilateral or bilateral exophthalmos is caused by varicose dilation of the orbital veins, such as can occur following trauma or in Osler's disease (polycythemia vera). Patients report protrusion of the eyeball of varying severity. Exophthalmos is usually unilateral and is especially prone to occur when the resistance to venous drainage is increased, as can occur when the patient presses, bends over, screams, or compresses the vessels of the neck. Occasionally the exophthalmos will be associated with increased filling of the episcleral and or conjunc-tival vessels. The disorder can be diagnosed in ultrasound studies using the Valsalva maneuver. A differential diagnosis should exclude a fistula between the carotid artery and cavernous sinus or an arteriovenous aneurysm, which is usually accompanied by a dramatic clinical picture with pulsation and increased intraocular pressure. In these clinical pictures, the ultrasound...
Rose bengal, as its name implies, is a red or rose colored dye. It specifically binds to mucus as well as to dead and devitalized tissue. It does not stain most epithelial defects and does not permeate the anterior chamber. Rose bengal is useful in the diagnosis of corneal and conjunctival damage secondary to ocular surface disease, such as dry eye and herpetic keratitis.
Dry eye, including its associated symptoms, is the most common presenting condition in ophthalmic practice. It is caused by a deficiency in 1 of the 3 layers composing the tear film. Dry eye is a condition that can be exacerbated by concurrent eyelid conditions, arid and windy environments, and extended near work. It is more frequently found in the elderly, it appears in women more than men, and it is associated with a number of systemic and dermatologic conditions. Systemic medications (including hormone replacement, birth control pills, steroids, and diuretics) may lead to this condition. Presenting symptoms include a gritty or sandy feeling, burning, and even paradoxical increased tearing. In any event, the standard first-line treatment is the use of tear supplementing artificial tear drops and lubricating ointments. The artificial tears and related ointments are designed to mimic the tears, substitute for the defective properties, and stabilize the existing tear film.
For many years, clinicians have valued the immunosuppressive effects of cyclosporine in the management of moderate to severe dry eye. Originally, however, it was used off-label and had to be formulated by a pharmacy. Topical steroids have also proved beneficial but have a lower safety profile for long-term use, with risks such as cataract formation and increased IOP. However, with the introduction of Restasis (Allergan), there is now a readily available, effective alternative to artificial tears and punctual occlusion in the management of dry eye. Restasis is the first commercially available ophthalmic cyclosporine drop.
Lymphomas are markedly radiosensitive. Primary radiotherapy for stage I indolent orbital lymphoma can achieve local control in more than 90 of patients, but the rate of distant relapse may be as high as 40 with external beam radiotherapy alone.21,22 The median total dose of radiation used in external beam radiotherapy for non-Hodgkin's lymphoma of the orbit is 40 Gy (range 20-50 Gy).22 Low-grade lesions are usually treated with a 30 Gy dose intermediate-grade lymphomas may be more appropriately treated with higher doses (
We reported two decades ago that biomolecules and molecular assemblages such as membranes and proteins can be stabilized in the dry state in the presence of a sugar found at high concentrations in many anhydrobiotic organisms, trehalose.1 We also showed that trehalose was clearly superior to other sugars in this regard.2 This effect seemed so clear it quickly led to wide-spread, and often uncritical, use of the sugar for preservation and other purposes. In fact, an array of applications for trehalose have been reported, ranging from stabilization of vaccines and liposomes to hypothermic storage of human organs.3 Other workers showed that it might even be efficacious in treatment of dry eye syndrome or dry skin in humans.4'5 Trehalose is prominendy listed as an ingredient in cosmetics, apparendy because it is reputed to inhibit oxidation of certain fatty acids in vitro that might be related to body odor.6 Trehalose has been shown by several groups to suppress free radical damage,...
Free radical formation has been implicated in a number of conditions, including cataracts, dry eye, and macular degeneration. The retina seems to be more susceptible to this damage than other tissues. Some studies suggest that the intake of antioxidant vitamins may help to delay the formation or slow the progress of these conditions. These relationships were extensively studied in a major multicenter clinical trial known as the Age-Related Eye Disease Study (AREDS). It was sponsored by the National Eye Institute, one of the federal government's National Institutes of Health. The AREDS set out to determine the natural history and risk factors of age-related macular degeneration (AMD) and cataract and to evaluate the effect of high doses of antioxi-dants and zinc on the progression of AMD and cataract.
An early sign of hypovitaminosis A is night blindness. This condition is related to the role of vitamin A as the prosthetic group of the visual pigment rhodopsin. The night blindness may progress to xerophthalmia (dryness and ulceration of the cornea) and blindness. Other symptoms of vitamin A deficiency include cessation of growth and skin changes due to hyperkeratosis.
High viscosity lubricants are useful in severely symptomatic dry eyes they have a tendency to blur vision but last longer than low viscosity products. If symptoms are not controlled by artifical tears, consider cyclosprine 0.05 oil enulsion (Restasis), temporary or permanent punctal occlusion therapy tarsorraphy may be considered for severe cases of exposure keratopathy. Dry Eyes Lubricant Eye Drops Insert, 5mg QD-BID For moderate to severe dry eye syndrome Dry Eyes Dry Eyes Lubricant Ointment
A 53-year-old woman developed subacute tetraplegia. Brain and spinal MRI was normal and CSF acellular. She made a partial recovery over 6 months after intravenous high-dose corticosteroids. Eighteen months later, she developed severe bilateral sequential optic neuritis and a left hemiplegia. Limb weakness partially improved, and her vision remained poor despite a further course of corticosteroids. Repeat MRI showed two infratentorial white matter lesions. MRI cervical cord showed an extensive cervical cord lesion extending over three levels. VEPs were delayed asymmetrically. She had unmatched CSF oligoclonal bands in addition to matched bands in the serum and CSF. She had a past history of two first-trimester miscarriages, an unprovoked ileofemoral deep vein thrombosis (DVT) for which she was on long-term warfarin, migraine, and one positive antiphospholipid antibody result. Her antineu-trophil antibody (ANA) was raised without more specific lupus autoantibodies. Three months on, she...
HTLV-1 was the first oncogenic retrovirus to be identified. HTLV-1 infection is endemic to the Caribbean, Central and South America, southern Africa, and Japan. It is linked to an adult form of T-cell leukemia characterized by a malignant proliferation of T lymphocytes and a neuromyelopathy, usually causing a progressive paraplegia. Ocular lesions may occur, including uveitis in 15 , keratoconjunctivitis sicca in 37 with a lymphoplasmacytoid infiltrate of salivary