Retinal vessel oximetry in children with inherited retinal diseases

Background Retinal vessel oximetry (RO) has been used to show altered metabolic function in patients with inherited retinal diseases (IRDs). The aim of this study was to investigate RO parameters of children with IRDs and presumed IRD carriers (pIRDc) and to compare them to controls. Methods In this cross-sectional cohort study, 142 eyes from 71 Caucasian subjects were included: 40 eyes with IRDs, 26 eyes with pIRDc and 76 control eyes. The oxygen saturation was measured with the Retinal Vessel Analyser (IMEDOS Systems UG, Jena, Germany). Mean oxygen saturations in the peripapillary retinal arterioles (A-SO2; %) and venules (V-SO2; %) were estimated, and their difference (A-V SO2; %) was calculated. In addition, we evaluated the mean diameter in all major retinal arterioles (D-A;mu m) and venules (D-V;mu m).anova-based linear mixed-effects models were calculated with SPSS(R). Results In general, children suffering from IRDs differed from controls when the A-SO(2)and A-V SO(2)were taken into account: both the A-SO(2)and the A-V SO(2)were significantly increased (p = 0.012). In subgroup analyses, children suffering from rod-cone dystrophy (RCD) presented an A-SO(2)increase (99.12 +/- 8.24%) when compared to controls (91.33 +/- 10.34%, p = 0.014) and pIRDc (92.37 +/- 6.57%, p = 0.065). For V-SO(2)significant changes in RCD (67.42 +/- 9.19%) were found in comparison with controls (58.24 +/- 11.74%, p < 0.041), pIRDc (56.67 +/- 7.16%, p = 0.007), cone-rod dystrophies (CRD, 52.17 +/- 5.32%, p < 0.001) and inherited macular dystrophies (IMD, 55.74 +/- 6.96%, p = 0.004), In addition, A-V SO(2)was decreased in RCD (31.69 +/- 3.92%) when measured against CRD (41.9 +/- 8.87%, p = 0.017) or IMD (39.52 +/- 8.95%, p = 0.059). Conclusion In general, we found that children with IRDs presented early metabolic changes. Within IRDs, children with RCD showed more affected metabolic changes. Thus, RO may support early screening to rule out IRDs in children, and more precisely may help to differentiate those suffering from RCD.

Automated summary

This study found that children with inherited retinal diseases show early metabolic changes, especially those with rod-cone dystrophy (RCD) being more affected. Retinal vessel oximetry may support early screening and differentiation of RCD in children.