A morphometric and stereologic analysis of ganglion cells of the central human retina.

Unbiased estimates of the cell density of the ganglion cell layer (GCL) were made by the Disector method, and the topography of the nerve fibre layer (NFL) between the centre of the fovea and the optic disc was studied, in human retina under both normal and pathological conditions. Three human retinae were examined, the eyes having been removed in the course of cancer surgery. Before operation two of the patients had visual acuity within normal limits. The third patient had impaired vision. In the two normal retinae, the cell densities of the GCL in the foveal wall were approximately 60,000/mm2. Estimates were also made outside the fovea and these showed a progressive reduction in cell density from the foveal wall towards the optic disc. The NFL simultaneously increased in thickness to approximately 70-100 microns at the peripapillary border. At 4 deg eccentricity nasal to the fovea the majority of axons had a mean diameter of less than 0.42 microns. Closer to the optic disc, the number of large axons increased in the inner parts of the NFL. In the third eye with long- and short-term visual impairment there was a substantial cell loss in the GCL, with only some 15,000 cells/mm2 in the foveal wall. In spite of cell/axon loss the thickness of the NFL was increased due to axonal swelling.