Central vision loss in one eye along with superior temporal vision loss in the fellow eye is characteristic of which visual field defect?

Central vision loss in one eye along with superior temporal vision loss in the fellow eye is characteristic of which visual field defect?

• A. Junctional scotoma
• B. Homonymous hemianopia
• C. Bitemporal hemianopia
• D. Altitudinal defect

Answer: (A)

A junctional scotoma occurs when a lesion sits at the junction of the optic nerve and the optic chiasm. Damage here hits the fibers serving central vision in the eye with the optic nerve involvement (the papillomacular bundle), producing central vision loss in that eye. At the same time, the lesion disrupts some of the crossing fibers at the chiasm that convey information from the other eye’s retina, specifically fibers carrying the superior-temporal field. The result is a contralateral, superior-temporal visual field defect in the fellow eye. This combination—central vision loss in one eye plus a superior-temporal defect in the other eye—is characteristic of a junctional scotoma. Other patterns don’t fit this exact combination. A post-chiasm lesion typically produces homonymous field loss in both eyes; bilateral bitemporal loss points to chiasmal compression affecting crossing nasal fibers in both eyes; and an altitudinal defect is usually limited to one eye’s upper or lower half due to retinal or optic nerve pathology.

A junctional scotoma occurs when a lesion sits at the junction of the optic nerve and the optic chiasm. Damage here hits the fibers serving central vision in the eye with the optic nerve involvement (the papillomacular bundle), producing central vision loss in that eye. At the same time, the lesion disrupts some of the crossing fibers at the chiasm that convey information from the other eye’s retina, specifically fibers carrying the superior-temporal field. The result is a contralateral, superior-temporal visual field defect in the fellow eye. This combination—central vision loss in one eye plus a superior-temporal defect in the other eye—is characteristic of a junctional scotoma.

Other patterns don’t fit this exact combination. A post-chiasm lesion typically produces homonymous field loss in both eyes; bilateral bitemporal loss points to chiasmal compression affecting crossing nasal fibers in both eyes; and an altitudinal defect is usually limited to one eye’s upper or lower half due to retinal or optic nerve pathology.