The Association Between Macula and ONH Optical Coherence Tomography Angiography (OCT-A) Vessel Densities in Glaucoma, Glaucoma Suspect, and Healthy Eyes.

PURPOSE: To evaluate strength of associations between optical coherence tomography (OCT)-angiography vessel density (VD) measurements in the macula and peripapillary region of the optic nerve head (ONH) with standard structural OCT thickness measures. MATERIALS AND METHODS: This cross-sectional study included 333 eyes of 219 primary open-angle glaucoma patients, 41 glaucoma suspects, and 73 healthy participants from the Diagnostic Innovations in Glaucoma Study (DIGS) with good quality OCT angiography images. The strength of associations between microvasculature measures in the ONH retinal nerve fiber layer (RNFL) and superficial macula layer was assessed using linear regression models. Associations between ONH and macula VD, and circumpapillary (cp) RNFL thickness and macular ganglion cell complex (mGCC) measures were also evaluated. RESULTS: The strength (r) of associations among VD and thickness measures of ONH and macula ranged from 14.1% to 69.4%; all were statistically significant (P<0.001). The association between ONH and macula whole-image VD (r=41.0%) was significantly weaker than the relationship between mGCC and cpRNFL thickness (r=69.4%, P<0.001). Although both cpRNFL and mGCC thicknesses tended to be more strongly associated with ONH VD (r=39.2% and 26.7%, respectively) than macula VD (r=27.5% and 17.7%, respectively), differences did not reach statistical significance (P=0.050 and P=0.113, respectively). CONCLUSIONS: The strength of the association of VD with cpRNFL and mGCC thicknesses varies by retinal layer. The weaker association of macula VD compared with ONH VD with tissue thickness may be due to differences in micorovasculature between the macula and ONH.

Period prevalence and incidence of optic disc haemorrhage in normal tension glaucoma and primary open-angle glaucoma.

BACKGROUND: To investigate and compare the period prevalences and incidences of optic disc haemorrhages in normal tension glaucoma and primary open-angle glaucoma. DESIGN: Hospital-based retrospective study. PARTICIPANTS: Four hundred and four patients with normal tension glaucoma and 210 patients with primary open-angle glaucoma that underwent consecutive disc examinations at least quarterly for at least 1 year and stereoscopic optic disc photographs at intervals of 6 to 12 months between 1992 and 2007. METHODS: The period prevalence of disc haemorrhages, gender predominance among patients with disc haemorrhage, and cumulative incidence of normal tension glaucoma and primary open-angle glaucoma were compared. MAIN OUTCOME MEASURES: Period prevalence, cumulative incidence, and gender predominance of DHs in patients with NTG and POAG. RESULTS: Three hundred and eighty-seven patients (387 eyes) of normal tension glaucoma patients and 205 patients (205 eyes) of primary open-angle glaucoma patients were finally enrolled in the study. The period prevalence and incidence rates of the stereoscopic optic disc photograph-confirmed glaucomatous disc haemorrhages were 33.3% (129/387), 0.46 ± 0.18 times/year in the normal tension glaucoma group, and 17.6% (36/205), 0.34 ± 0.23 times/year in the primary open-angle glaucoma group, respectively. The absolute values and ratios of primary open-angle glaucoma and normal tension glaucoma in period prevalences and incidence rates in the present study were higher than in previous studies. No significant difference in gender ratios was found between patients that did or did not develop disc haemorrhage for both types of open-angle glaucoma (P > 0.05, respectively). CONCLUSIONS: The primary open-angle glaucoma group had higher period prevalences and incidence rates of disc haemorrhage than those reported previously. Disc haemorrhages were found to develop independent of gender.