Sellar And Parasellar Tumors

reverse may occur in lesions compressing the chiasm from above, such as craniopharyngioma. Field loss often begins unilaterally when the intracranial optic nerve is compressed close to its junction with the chiasm. Decussating fibers from the nasal retina of the other eye loop forwards into the optic nerve for a short distance before turning through 180° and passing backwards into the optic tract. Early additional involvement of such decussating fibers is signaled by a small contralateral upper temporal or "junctional" defect. Patients frequently complain of bumping into objects on one or both sides of the contracted visual field, reflecting both unilateral and bitemporal field loss. The affected field is described as absent, or blank, rather than black (blackness is usually a symptom of retinal rather than optic fiber disease). Central vision may be affected by direct compression of the intracranial optic nerve. This may present as a blurring of vision or scotomatous central field defects. This is more common in individuals with a "post-fixed" chiasm - an anatomical variation where the chiasm is situated further back, thus exposing more optic nerve to the compres-sive effects of an expanding adenoma. If compression has been longstanding, fundoscopy may reveal optic atrophy. Diplopia usually signals lateral compression of the nerves in and around the cavernous sinus either by gradual lateral extension or apoplexy. Optic tract compression in a "pre-fixed" chiasm (the opposite of a post-fixed chiasm) is rare and may produce an homonymous field pattern that may be incongruous.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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