Predicting the Magnitude of Functional and Structural Damage in Glaucoma From Monocular Pupillary Light Responses Using Automated Pupillography.

PURPOSE: To predict the magnitude of functional damage [mean deviation (MD) on visual field examination] and structural damage [retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness on spectral domain optical coherence tomography] in glaucoma from monocular pupillary light response measurements using automated pupillography. METHODS: In total, 59 subjects (118 eyes) with either a confirmed or suspected diagnosis of glaucoma underwent automated pupillography, along with visual fields and spectral domain optical coherence tomography examinations. Association between pupillary light response measurements of each eye [amplitude of constriction, latency of onset of constriction (Loc), latency of maximal constriction (Lmaxc), velocity of constriction and velocity of redilation] and corresponding MD, average RNFL, and average GCC measurements were evaluated using univariate and multivariate regression analysis after accounting for the multicollinearity. Goodness of fit of the multivariate models was evaluated using coefficient of determination (R). RESULTS: Multivariate regression models that contained Loc and Lmaxc showed the best association with MD (R of 0.30), average RNFL thickness (R=0.18) and average GCC thickness (R=0.26). The formula that best predicts the MD could be described as: MD=-14.06-0.15×Loc+0.06×Lmaxc. The formula that best predicts the average RNFL thickness could be described as: Average RNFL thickness=67.18-0.22×Loc+0.09×Lmaxc. CONCLUSIONS: Glaucomatous damage as estimated by MD, RNFL, and GCC thickness measurements were best predicted by the latency parameters (Loc and Lmaxc) of pupillography. Worsening of glaucomatous damage resulted in a delayed onset of pupillary constriction and a decreased Lmaxc.

Comparing the Performance of Compass Perimetry With Humphrey Field Analyzer in Eyes With Glaucoma.

PURPOSE: To evaluate the reliability indices [fixation losses, false negative response rates (FN) and false positive response rates] and threshold sensitivities obtained from glaucoma patients with a Compass perimeter and to compare the same with the Humphrey field analyzer (HFA). METHODS: In a cross-sectional study, 97 eyes of 58 subjects (64 glaucoma and 33 glaucoma suspect eyes) underwent visual field examination with Compass and HFA. Any test with a fixation losses, FN or FP of >20% was considered unreliable. Reliability indices and threshold sensitivities between the 2 instruments were compared and the agreement evaluated using Bland and Altman analysis. RESULTS: In total, 37 tests (38%) with Compass and 17 (18%) with HFA were unreliable. The number of unreliable tests due to high FN (>20%) was significantly more (P=0.005) with Compass (n=27) than HFA (n=3). The mean difference [95% limits of agreement (LoA)] in mean sensitivity between Compass and HFA in the 51 eyes with reliable Compass and HFA results was -0.7 dB (-5.6, 4.3 dB). The point-wise threshold sensitivities with Compass were lower than that with HFA in central and temporal but higher in the nasal field. The 95% LoA ranged from -8 to +5 dB at one of the central points to -20 to +20 dB at one of the peripheral points. CONCLUSIONS: The numbers of unreliable tests were higher with Compass compared with HFA. The LoA between Compass and HFA for point-wise threshold sensitivities as well as the global indices were wide, implying that the instruments cannot be used interchangeably.

Predicting the intereye asymmetry in functional and structural damage in glaucoma using automated pupillography.

PURPOSE: To predict the intereye asymmetry in functional (mean deviation, MD on visual field, VF) and structural (retinal nerve fibre layer, RNFL and ganglion cell complex, GCC thickness on spectral domain optical coherence tomography, SDOCT) measurements in glaucoma using the automated pupillography parameters. METHODS: Fifty-nine subjects with a diagnosis of either glaucoma or glaucoma suspect underwent automated pupillography along with VF and SDOCT examinations. Association between pupillography and the absolute intereye difference in MD, RNFL and GCC measurements was evaluated using regression analysis after accounting for the multicollinearity. RESULTS: Univariate regression analysis showed statistically significant associations (p < 0.05) between multiple pupillography parameters and the intereye difference in MD, RNFL and GCC thickness measurements. Multivariate regression with less strongly correlated parameters identified intereye difference in amplitude change (Ac) per cent to be the parameter that best predicted the intereye asymmetry in MD (Intereye asymmetry in MD = 2.20 + 1.33*intereye difference in Ac per cent, R2  = 0.36), RNFL thickness (3.38 + 3.55*intereye difference in Ac per cent, R2  = 0.49) and GCC thickness (4.49 + 2.06* intereye difference in Ac per cent, R2  = 0.41). Ability of intereye Ac per cent difference to predict intereye asymmetry in MD, RNFL and GCC thickness was better in patients with angle closure disease (R2  = 0.38, 0.79, 0.66, respectively) compared to those with open angles (R2  = 0.25, 0.15, 0.16, respectively). CONCLUSIONS: Intereye asymmetry in MD, RNFL and GCC thickness measurements was best predicted by the intereye difference in Ac per cent on automated pupillography. The predicting ability was better in patients with angle closure compared to those with open angles.

Regional Comparisons of Optical Coherence Tomography Angiography Vessel Density in Primary Open-Angle Glaucoma.

PURPOSE: To compare the diagnostic abilities of the vessel densities in optic nerve head (ONH), peripapillary, and macular regions measured using optical coherence tomography angiography (OCTA) in eyes with primary open-angle glaucoma (POAG), and to evaluate the effect of glaucoma severity (based on the mean deviation, MD), optic disc size, and pretreatment intraocular pressure (IOP). DESIGN: Cross-sectional study. METHODS: Seventy-eight eyes of 53 control subjects and 64 eyes of 39 POAG patients underwent OCTA imaging. Area under receiver operating characteristic (ROC) curves (AUC) and sensitivities at fixed specificities of vessel densities in ONH, peripapillary, and macular regions were analyzed. ROC regression was used to evaluate the effect of covariates on the diagnostic abilities. RESULTS: The AUCs of ONH vessel densities ranged between 0.59 (superonasal sector) and 0.73 (average inside disc), peripapillary between 0.70 (nasal, superonasal and temporal) and 0.89 (inferotemporal), and macular between 0.56 (nasal) and 0.64 (temporal). AUC of the average peripapillary vessel density was significantly better than the average inside disc (P = .05) and macular (P = .005) measurement. MD showed a negative association with the AUCs of the vessel densities of all regions. Pretreatment IOP (coefficient: 0.09) showed a significant (P < .05) effect on the AUC of ONH vessel density. CONCLUSIONS: Diagnostic ability of the vessel density parameters of OCTA was only moderate. Macular and inside disc densities had significantly lower diagnostic abilities in POAG than the peripapillary density. Diagnostic abilities of vessel densities increased with increasing severity of glaucoma and that of ONH vessel density with higher pretreatment IOPs.