A macula-involving homonymous hemianopsia is most likely caused by which?

A macula-involving homonymous hemianopsia is most likely caused by which?

• A. Stroke
• B. Compressive tumor
• C. Both
• D. Neither

Answer: (B)

Macula-involving homonymous hemianopsia points to a post-chiasmal lesion that disrupts the fibers carrying central vision. The macula has a large cortical representation and, with a vascular supply that can be resilient in sudden strokes, central vision is often spared in typical vascular events. A slowly enlarging compressive tumor, on the other hand, tends to affect the posterior optic radiations or occipital cortex more diffusely and in a way that includes the macular (central) fibers, producing a homonymous hemianopia that involves central vision. This gradual, mass-effect pattern is more consistent with macula-involving defects.

Macula-involving homonymous hemianopsia points to a post-chiasmal lesion that disrupts the fibers carrying central vision. The macula has a large cortical representation and, with a vascular supply that can be resilient in sudden strokes, central vision is often spared in typical vascular events. A slowly enlarging compressive tumor, on the other hand, tends to affect the posterior optic radiations or occipital cortex more diffusely and in a way that includes the macular (central) fibers, producing a homonymous hemianopia that involves central vision. This gradual, mass-effect pattern is more consistent with macula-involving defects.