What causes inferior altitudinal visual field defect?

Altitudinal visual field defect is a rare presentation of retrochiasmal lesion especially when bilateral visual fields were affected. In fact, bilateral inferior altitudinal visual field defect (BIAVFD) usually occurred in patients who survived a gunshot injury to the occipital lobe or as a direct trauma to the brain.

What are glaucomatous visual field defects?

Glaucomatous visual field defects are basically comprised of four major patterns: an isolated scotoma, an arcuate scotoma, a nasal step, and generalized depression. The field loss progresses conforming to the optic nerve head and retinal nerve fiber changes.

What is altitudinal field loss?

An altitudinal visual field defect is a condition in which there is defect in the superior or inferior portion of the visual field that respects the horizontal midline. The optic nerve in altitudinal visual field loss may show sector or diffuse edema, be normal, or show optic atrophy.

What is a localized visual field defect?

DEFINITION. Visual defects are localized defects in a person’s visual field. They can occur from a variety of causes such as trauma to the brain or visual pathway, diseases and disorders of the eye, optic nerve or the brain and systemic vascular disease.

What is scotoma visual defect?

A scotoma is an aura or blind spot that obstructs part of your vision. Scintillating scotomas are blind spots that flicker and waver between light and dark. Scintillating scotomas are typically not permanent. But they can be an indicator of an underlying health condition.

What is Foster Kennedy syndrome?

Foster-Kennedy Syndrome is characterized by unilateral visual loss with a compressive optic atrophy in one eye and contralateral papilledema caused by increased intracranial pressure.

Can you cheat a visual field test?

Visual field defect simulations were exaggerated beyond what was reasonable. Conclusion: This study reports on whether it is possible to cheat with automatic perimetry. The different parameters analyzed by computer programs are not able to detect cheating patients.

Which visual field is affected in glaucoma?

Glaucoma is characterized by a chronic progressive optic neuropathy with corresponding and characteristic patterns of visual field (VF) loss. In the majority of patients, VF changes are initially localized and as the disease progresses, these focal areas become wider, deeper, and more numerous.

What causes a visual field defect?

Causes of visual field defects are numerous and include glaucoma, vascular disease, tumours, retinal disease, hereditary disease, optic neuritis and other inflammatory processes, nutritional deficiencies, toxins, and drugs. Certain patterns of visual field loss help to establish a possible underlying cause.

Why is it called Foster Kennedy syndrome?

Foster-Kennedy Syndrome is characterized by unilateral visual loss with a compressive optic atrophy in one eye and contralateral papilledema caused by increased intracranial pressure. The same ophthalmoscopic features however can be seen in the pseudo-Foster-Kennedy Syndrome.

What causes altitudinal visual field defects in NMO?

An altitudinal visual field defect is suggestive of ischemic optic neuropathy, which occasionally is the result of posterior ciliary artery occlusion [ 28, 29 ]. We suggest that ischemic mechanism mediated by anti-AQP4 antibody may play a role in ON for NMO patients.

Which is a characteristic visual field defect of optic neuritis?

Central scotoma is recognized as a characteristic visual field defect pattern of optic neuritis (ON), however, the differing pathogenic mechanisms of NMO and MS may result in different patterns of visual field defects for ON. Medical records of 15 patients with NMO and 20 patients with MS having ON were retrospectively analyzed.

Who are patients with superior altitudinal field defect?

Some patients with bilateral optic neuropathies particularly those who develop bilateral simultaneous or non-simultaneous ante- rior ischaemic optic neuropathy(AION ) develop a superior altitudinal field defect in one eye and an inferior altitudinal field defect in the other.

How many eyes are affected by optic neuritis?

In a study of 448 patients with acute optic neuritis, 48.2% of affected eyes had diffuse visual field loss, 20.1% of eyes had altitudinal or other nerve fiber bundle-type defects, and 8.3% had central or cecocentral scotomas (Keltner, 1993).