What causes altitudinal defect?

Published by Charlie Davidson on

What causes altitudinal defect?

Altitudinal visual field defect (VFD), which involves the loss of visual sensation in the horizontal half of the visual field, is caused mainly by anterior ischemic optic neuropathy (AION),1,2,3 or rarely by compressive neuropathy due to a tumor or aneurysm.

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 is a superior visual field defect?

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 altitudinal defect can be unilateral or bilateral.

What causes superior quadrantanopia?

A superior quadrantanopia results from an insult to the optic radiation inferiorly in the temporal lobe, resulting in a ‘pie in the sky’ type of visual field defect (Figure 1d), while an inferior quadrantanopia is caused by damage to the parietal lobe optic radiation (Figure 1e).

What is field defect?

A visual field defect is a loss of part of the usual field of vision, so it does not include severe visual impairment of either one eye or both. The lesion may be anywhere along the optic pathway; retina to occipital cortex.

How is visual field loss treated?

Most research has focused on three treatment approaches: restorative training, optical aids, and compensatory training. The restorative approach is the most ambitious, aiming to reduce the visual field loss through prolonged training.

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.

Are there any cases of Bitemporal visual field defects?

Considering that Mrs. Ross had bitem­poral visual field defects that did not respect the midline, negative imaging studies for an optic chiasmal lesion, and tilted disc insertion that was confirmed on clinical evaluation and ultrasound B-scan, we diagnosed her with tilted disc syndrome.

What does it mean to have a visual field defect?

A visual field defect is a loss of part of the usual field of vision, so it does not include severe visual impairment of either one eye or both. The lesion may be anywhere along the optic pathway; retina to occipital cortex.

When does tilted disc syndrome cause visual field defects?

Visual field defects. When tilted disc is found bilaterally, the visual field defects may mimic optic chiasm disorders. 1 Axonal dysgenesis causes the visual field defects that occur with tilted disc syndrome. 2 These defects generally involve the temporal and superior visual field but may appear as an enlarged blind spot.

What causes visual field defects in the parietal lobe?

A superior quadrantanopia results from an insult to the optic radiation inferiorly in the temporal lobe, resulting in a ‘pie in the sky’ type of visual field defect (Figure 1d), while an inferior quadrantanopia is caused by damage to the parietal lobe optic radiation (Figure 1e).

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