Question

Incongruous Homonymous hemianopia with Wernicke's hemianopia pupil is seen with the lesion of

• A. Optic radiation
• B. Lateral geniculate body
• C. Optic tract
• D. Anterior occipital cortex

Answer 1

The Correct Option is C

The condition described involves incongruous homonymous hemianopia with a Wernicke's hemianopia pupil defect. This specific type of visual field defect is most commonly associated with a lesion of the optic tract. Let's break down the reasoning step by step:

• Visual Pathway: The visual pathway consists of several key structures that process visual information from the retina to the brain, including the optic nerve, optic chiasm, optic tract, lateral geniculate body (LGB), optic radiation, and visual cortex.
• Homonymous Hemianopia: This condition refers to a loss of half of the visual field in both eyes on the same side (either left or right). This type of visual field defect suggests a post-chiasmal lesion.
• Incongruous Hemianopia: When the visual field defect is "incongruous," it means the severity of the field loss is not identical in both eyes, often suggesting a damage site closer to the chiasm rather than further along the pathway.
• Wernicke's Hemianopia Pupil Phenomenon: This refers to an abnormal pupil response associated with lesions in the visual pathways that disrupt the pathway for pupillary light reflex. Notably, it indicates the involvement of fibers affecting pupillary response, which is characteristic of optic tract lesions.

Considering all these points, a lesion affecting the optic tract typically results in incongruous homonymous hemianopia with the described pupillary defect. Thus, the correct answer is the optic tract.