PURPOSE. To evaluate the changes in circumpapillary vessel density (cpVD) and retinal nerve fiber layer (RNFL) thickness after an acute primary angle closure (APAC) episode. METHODS. Twenty-eight patients (28 pair of eyes) with unilateral APAC and 39 normal subjects (64 eyes) were included in this prospective, observational study. cpVD as measured by optical coherence tomography angiography and RNFL thickness as measured by spectral-domain optical coherence tomography were compared at 6 weeks after an APAC episode between affected, unaffected, and normal eyes. cpVD and RNFL thickness at 1 week and 6 weeks after APAC were also compared in APAC eyes in qualified images. RESULTS. At 6 weeks, cpVD was significantly lower in APAC eyes (57.3% 6 6.8%), compared to fellow eyes (63.1% 6 3.5%) and control eyes (63.6% 6 3.4%) (P < 0.001). There was diffuse microvascular dropout with greater vessel density loss in the superonasal sector. APAC eyes had thinner RNFL globally and in each sector (except temporal and nasal sectors) than in fellow and normal eyes at 6 weeks. cpVD in the affected eyes was significantly greater at 1 week (56.3% 6 5.3%) than values at 6 weeks (53.5% 6 7%) (P ¼ 0.003) but less than cpVD in the fellow eyes (62.4% 6 5.0%) (P < 0.001). RNFL thickness for the APAC eyes at 1 week (120.6 6 18.0 lm) was greater than the analogous values for affected eyes (90.1 6 13.2 lm; P ¼ 0.037) and fellow eyes at 6 weeks (102.5 6 5.7 lm; P ¼ 0.001). CONCLUSIONS. Vessel density decreased over 6 weeks after an APAC episode compared with the contralateral unaffected eyes. In contrast, there was an initial increase in RNFL thickness that was followed by a subsequent decrease.

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Citation: Aghsaei Fard M, Salabati M, Mahmoudzadeh R, et al. Automated evaluation of parapapillary choroidal microvasculature in ischemic optic neuropathy and open angle glaucoma. Invest Ophthalmol Vis Sci. 2020;61(3):35. https://doi.org/10.1167/iovs.61.3.35 PURPOSE.To determine whether parapapillary choroidal microvasculature (PPCMv) density as measured by optical coherence tomography angiography differs between nonarteritic anterior ischemic optic neuropathy (NAION) and primary open angle glaucoma (POAG). METHODS.Thirty-seven eyes with chronic NAION, 34 unaffected fellow eyes with NAION, 47 moderate and severe POAG eyes, and 54 healthy control subjects were evaluated. Automated PPCMv density was calculated using custom Matlab software in inner and outer annuli around the optic nerve region in addition to peripapillary superficial retinal vessels. RESULTS.Linear models showed no difference in peripapillary retinal nerve fiber layer between NAION and POAG eyes. Mean peripapillary superficial small vessels in the NAION and POAG groups were 36.62 ± 7.1% and 39.72 ± 8.18% without a statistically difference between them (P = 0.16). Mean inner and outer annular region PPCMv densities in the NAION group were 26.55 ± 9.2% and 17.81 ± 6.9%, which were not different from unaffected fellow eyes and the control group. However, the POAG group had significantly reduced PPCMv density in both inner and outer annuli with values of 15.84 ± 6.5% and 12.80 ± 5.0%, respectively, compared with normal subjects (both P < 0.001). Inner and outer circle PPCMv densities were also significantly reduced in the POAG group compared with the NAION group. CONCLUSIONS. ReducedPPCMv density in POAG eyes shows that deep optic nerve head ocular blood flow may contribute to axonal damage in patients with glaucoma.

In TED patients, CH seems to be lower than in normal subjects. GAT might underestimate the IOP due to differences in corneal properties of cornea in TED patients.