Objective To determine the long-term changes in optic disc parameter and the thickness of circumpapillary retinal nerve fiber layer (CP-RNFL) and macular retina after acute primary angle closure. Methods Prospective clinical case-control study. A total of 26 patients (30 eyes) with acute primary angle-closure glaucoma (APACG) were in the APACG group, whose intraocular pressure were control after a single episode acute primary angle closure; 30 age-and sex-matched healthy subjects (30 eyes) in the control group. All subjects underwent three dimensional optical coherence tomography (3D-OCT) examination with 3D optic disk scanning or circle optic disk scanning and 6 mm×6 mm macular scanning. The parameters included average thickness of entire CP-RNFL, thickness of nasal, superior, temporal and inferior quadrant of CP-RNFL, disc area, disc cup area, rim area, cup/disc (C/D) area ratio, C/D horizontal diameter ratio and C/D vertical diameter ratio. The foveal retinal thickness, center retinal thickness (≤1 mm from the fovea), 4 quadrants of macular inner-ring ( > 1 mm but≤3 mm from the fovea) retinal thickness, 4 quadrants of macular outer-ring ( > 3 mm but≤6 mm from the fovea) retinal thickness, average thickness of macular retinal thickness and macular volume were measured and analyzed. Results The disc area, disc cup area, C/D area ratio, C/D horizontal diameter ratio and C/D vertical diameter ratio in APACG group were significantly bigger than the control group (t=3.22, 4.12, 3.90, 3.00, 3.23; P < 0.05), rim area was smaller than the control group (t=-2.63, P < 0.05). The average thickness (t=-6.68) and the thickness of superior (t=-5.90), temporal (t=-11.64) and inferior (t=-5.06) quadrants of CP-RNFL, center retinal thickness (t=-2.50), 4 quadrants of macular inner-ring retinal thickness (t=-4.91, -4.88, -2.83, -3.59), nasal (t=-2.13) and superior (t=-2.49) quadrants of macular outer-ring retinal thickness as well as average thickness of macular retinal thickness (t=-2.65) were significantly thinner than the control group (P < 0.05), and the macular volume (t=-2.69) was significantly smaller than the control group (P < 0.05). There was no statistically difference at nasal CP-RNFL (t=-0.11), foveal retinal thickness (t=-0.59), temporal (t=-0.67) and inferior (t=-1.02) quadrants of macular outer-ring retinal thickness between two groups (P > 0.05). Conclusions In comparison with the healthy subjects, the disc area, disc cup area, C/D area ratio, C/D horizontal diameter ratio, C/D vertical diameter ratio in APACG eyes were bigger, while rim area was smaller; the CP-RNFL and macular retinal thickness were thinner except nasal CP-RNFL, fovea, temporal and inferior quadrants of macular outer-ring retinal.
ObjectiveTo compare the lamina cribrosa parameters between primary open angle glaucoma (POAG) and chronic primary angle closure glaucoma (CPACG) eyes. MethodsA total of 73 POAG eyes (73 subjects), 64 CPACG eyes (64 subjects), and 40 normal control eyes (40 subjects) with matched ages were included in this cross-sectional observational study. No significant difference was found in sex (χ2=2.07) and age (F=0.38) among three groups (P > 0.05). The intraocular pressure, average retinal nerve fiber layer (RNFL) thickness and average visual field defect were not significantly different between POAG and CPACG patients (F=15.67, 21.15, 44.40, 27.99; P < 0.05). All subjects underwent spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI). The optic nerve head was scanned radially at the angle of 20; six high resolution B-scan images were obtained from each eye. The center and para-center lamina cribrosa thickness (LCT) and anterior lamina cribrosa surface depth (ALCSD) were measured in each image. The mean LCT and ALCSD were recorded as the average of the LCT and ALCSD of the 6 images and compared among POAG, CPACG and normal control eyes. ResultsThe average LCT of normal control eyes were (211.48±12.07) μm, while those of the POAG eyes were (145.43±34.33) μm, CPACG eyes were (156.79±33.66) μm. The mean LCT of the POAG and CPACG eyes were thinner than those of the control eyes (t=-11.76, -9.88; P < 0.01). All LCT of the POAG eyes were significantly thinner than those of the CPACG eyes (t=-1.96, P=0.03).The average ALCSD of normal control eyes were (390.73±84.40) μm, while those of the POAG eyes were (558.51±176.66) μm, CPACG eyes were (539.39±177.30) μm, respectively. The average ALCSD of the POAG and CPACG eyes were deeper than those of the control eyes (t=5.65, 4.96; P < 0.01). But no significantly different ALCSD was shown between POAG and CPACG eyes (t=0.63, P=0.49). ConclusionsPOAG and CPACG eyes have thinner LCT and deeper ALCSD than normal eyes. POAG eyes have thinner LCT than CPACG eyes when their visual field defect and damage of RNFL were in the same degree.