Purchase this article with an account.
Howard Lockwood, Juan Reynaud, Stuart Keith Gardiner, Jonathan L Grimm, Vincent Libertiaux, J Crawford C Downs, Hongli Yang, Claude F Burgoyne; Global Lamina Cribrosa (LC) Microarchitectural (LMA) Change in Non-Human Primate (NHP) Early Experimental Glaucoma (EG). Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):6151.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To calculate Physiologic Inter-eye Percent Difference (PIPD) values1 for LC Beam Diameter (BD), Pore Diameter (PD), Connective Tissue Volume Fraction (CTVF), Connective Tissue Volume (CTV) and Laminar Volume (LV) within 4 Bilateral Normal (BN) NHPs and compare them to EG vs Control eye differences within 17 NHP (1.9 - 21.9 years old) sacrificed at the onset of early EG.2,3
Optic Nerve Heads (ONH) underwent digital 3D reconstruction1,3 and LC beam segmentation.4 Each beam and pore voxel was assigned a diameter based on the largest sphere that contained it. Global mean BD, mean PD, CTVF, CTV and LV for all ONHs were calculated. PIPDmax values for each parameter were defined1 to be the maximum value of their inter-eye difference within the 4 BN NHPs. For each parameter, the number of animals in which EG vs Control eye differences exceeded PIPDmax values were noted and the effect of EG was assessed by ANOVA. Demographic, ocular and biometric factor effects on EG eye change were assessed by multivariate regression.
PIPD Ranges for the 4 BN NHPs are reported in Table 1. Overall, EG effects were significant for BD (p=.0290), CTV (p<.0001) and LV (p<.0001). EG eye differences achieving PIPDmax criteria (Table 2) included: 1) BD increases in 5 eyes (14.1 to 23.2%) and decreases in 2 eyes (10.4 and 31.5%); 2) PD increases in 9 eyes (16.2 to 37.6%); 3) a CTVF decrease in 1 eye by -32.8%; 4) CTV increases in 12 eyes (22.7 to 127.9%) and a decrease in one eye by 22.4%; and 5) LV increases in 14 eyes (15.4 to 145.5%). PIPDmax decreases only occurred in BD, CTVF and CTV and only in the two animals with the highest Control Eye CTVF (Table 2). Age and Male Gender (negatively) and Control eye BMO area (positively) affected EG eye BD % change (p<.05). Age negatively affected CTVF % change.
Between-eye LMA differences are substantial within BN NHPs requiring EG eyes to be from 10.3% to 21.3% different from their control eyes to achieve PIPDmax criteria. Increases in BD, PD, CTV and LV are common in early NHP EG. While CTV and LV increase, CTVF remains stable in most EG eyes. Age, Gender, BMO area and Baseline CTVF may influence the character of laminar remodeling in NHP early EG. 1Yang H, et al. IOVS 2009;50:224-234. 2He L, et al. IOVS 2014;55:574-586. 3Yang H, et al. IOVS 2011;52:345-363. 4Grau V, et al. IEEE Trans Med Imaging 2006;25:245-255
This PDF is available to Subscribers Only