Purpose: Aquired transsynaptic retrograde degeneration of the human visual system can be identified using magnetic resonance imaging (MRI) and optical coherence tomography (OCT), which can reveal optic tract atrophy, retinal nerve fiber layer loss, and ganglion cell complex (GCC) thinning. We investigated GCC changes in the first 4 years following post-geniculate lesions.
Methods: Nine patients with congruous homonymous hemianopia were scanned with OCT. A 6-mm circle centered on the macula was divided vertically into hemianopia (H) and unaffected (U) sides. GCC and retinal thicknesses were calculated using an average for both eyes and compared with the hemianopia/unaffected side (H/U) ratio. The relationship between the H/U ratio of GCC and time elapsed since occipital damage was evaluated.
Results: The average GCC thicknesses was 89.1 and 96.6 μm, and of the retina 295.7 μm and 292.7 μm in the H and U sides, respectively. The H/U ratio of GCC at 0.92 was significantly lower than of the retina at 0.99 (p=0.042). Regression analysis revealed a negative linear relationship (linear regression r=-0.868, p=0.012) described by the equation: H/U ratio of GCC=0.99-0.004×elapsed time (months).
Conclusion: For 4 years following post-geniculate damage, GCC on the hemianopia side decreased approximately 5% per year while the retinal thickness was almost unchanged.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 117: 918-924, 2013.