New England College of Optometry, Boston, Massachusetts, United States.
College of Optometry, University of Houston, Houston, Texas, United States.
Invest Ophthalmol Vis Sci. 2021 Jan 4;62(1):5. doi: 10.1167/iovs.62.1.5.
Loss of ganglion cell inner plexiform layer (GCIPL) and visual sensitivity in the macula region are known to occur at all stages of glaucoma. While both are dependent on the underlying retinal ganglion cells (RGCs), the relationship between structure and function is modest. We hypothesize that the imprecise relationship is due to a lack of direct correspondence between in vivo measures and RGC counts, as well as the relatively large stimulus size used by standard perimetry, which exceeds spatial summation.
The relationship between optical coherence tomography (OCT)-derived GCIPL thickness and corresponding inner cell density from retinal flat mounts was determined for four nonhuman primates with varying stages of neuropathy. Normative data for 10-2 threshold using Goldman size I to V stimuli were established for 10 animals, 4 of which were then followed longitudinally with OCT and perimetry. The relationship between GCIPL volume, which incorporated stimulus size after removal of residual thickness, and differential light sensitivity was determined for both experimental glaucoma and healthy eyes.
Peak inner retinal cell density was 63,052 ± 9238 cells/mm2 in the healthy eye. Cell density was related to both GCIPL thickness and eccentricity (R2 = 0.74, P < .01). For all 10-2 eccentricities, size III stimuli were greater than the critical area (P < 0.01). Based on the structural and histologic relationship, the critical area corresponds to approximately 156 RGCs.
The relationship between cell density and GCIPL thickness is dependent on retinal eccentricity. For 10-2 perimetry, perimetric loss, especially at earlier stages of neuropathy, may best be detected using size II or smaller stimuli.
已知在青光眼的所有阶段都会出现神经节细胞内丛状层（GCIPL）和黄斑区视觉敏感性的丧失。虽然这两者都依赖于底层的视网膜神经节细胞（RGCs），但结构与功能之间的关系并不密切。我们假设这种不精确的关系是由于体内测量值与 RGC 计数之间缺乏直接对应关系，以及标准视野检查中使用的相对较大的刺激大小超过了空间总和。
我们确定了四只患有不同程度神经病变的非人类灵长类动物的光学相干断层扫描（OCT）衍生的 GCIPL 厚度与视网膜平面上相应的内细胞密度之间的关系。为 10 只动物建立了 10-2 阈值的 Goldmann 大小 I 至 V 刺激的正常数据，其中 4 只随后进行了 OCT 和视野检查的纵向随访。我们确定了去除剩余厚度后纳入刺激大小的 GCIPL 体积与差分光敏感性之间的关系，这适用于实验性青光眼和健康眼。
健康眼中的峰值内视网膜细胞密度为 63052±9238 个/平方毫米。细胞密度与 GCIPL 厚度和偏心度都有关（R2=0.74，P<.01）。对于所有 10-2 偏心度，III 型刺激都大于临界区域（P<.01）。基于结构和组织学关系，临界区域对应大约 156 个 RGCs。
细胞密度与 GCIPL 厚度之间的关系取决于视网膜偏心度。对于 10-2 视野检查，尤其是在神经病变的早期阶段，使用 II 型或更小的刺激可能更能检测到视野损失。
