Primary angle-closure eyes with ocular hypertension show preperimetric ganglion cell complex abnormalities

The present study aimed to investigate ganglion cell complex (GCC) and peripapillary retinal nerve fiber layer (pRNFL) parameters in subjects with primary angle closure (PAC) without raised intraocular pressure (IOP), PAC eyes with raised IOP, and those with early primary angle-closure glaucoma (PACG), to ascertain parameters that could identify any early glaucomatous damage.

This was an observational, cross-sectional study of 75 patients with PAC, PAC with ocular hypertension (OHT), and early PACG. GCC analysis was performed by spectral domain-optical coherence tomography (SD-OCT) using RTVue-100 software, and parameters were compared between these groups.

In eyes with PAC, PAC with OHT and early PACG, the average GCC thickness was 92.49 ± 7.52, 87.69 ± 5.24, and 79.64 ± 8.45 µm; inferior GCC thickness was 92.8 ± 7.84, 88.15 ± 6.13, and 79.59 ± 8.96 µm; and superior GCC thickness was 92.08 ± 7.55, 87.23 ± 5.19, and 79.67 ± 8.82 µm, respectively. There was a significant difference in all parameters between PAC vs PAC OHT eyes (P = 0.001), as also between PAC OHT vs early PACG eyes (P < 0.001). The percentage GCC loss in eyes from PAC to PAC with OHT and from PAC with OHT to early PACG in average GCC was 7.5 ± 3.95% (P = 0.001) and 9.31 ± 8.54% (P < 0.001). pRNFL showed a significant difference in all the parameters between PAC OHT vs early PACG (P < 0.001); however, only the superior pRNFL was significantly different between PAC vs PAC OHT (P = 0.01).

PAC with OHT showed significant, preperimetric GCC changes that could identify early progression from PAC to PACG and prompt appropriate therapy to prevent morbidity.