Abstract
It is generally believed that patients with homonymous hemianopia with retrogeniculate lesions show no funduscopic abnormality. Spectral-domain optical coherence tomography(SD-OCT)and swept-source OCT(SS-OCT)allow us to investigate whether this is true. Recently, we treated patients with homonymous hemianopia following unilateral posterior cerebral artery(PCA)infarction and evaluated the macular ganglion cell complex(GCC)thicknesses using SD-OCT. We clearly detected reduced GCC thickness associated with retinal ganglion cells(RGC)loss. Our findings suggest that degeneration of RGCs corresponding to the side of the homonymous hemianopia can occur within a few years after PCA infarction and, furthermore, that the measurement of GCC thickness may detect nerve fiber damage in homonymous hemianopia before that of the circumpapillary retinal nerve fiber layer Use of SS-OCT suggested that thinning of the GCC was more prominent in the central retina than in the periphery. Furthermore, our findings suggested that thinning of the GCC is slowly progressive over time. These findings may possibly be explained by trans-synaptic retrograde degeneration of the RGCs and their fibers; however, PCA infarction may also directly affect the axons of RGCs in the anterior visual pathways.
