Morphologic and Functional Assessment of Photoreceptors After Macula-Off Retinal Detachment With Adaptive-Optics OCT and Microperimetry.

PURPOSE: Limited information is available on morphologic and functional regeneration of photoreceptors after retinal detachment (RD) surgery. This observational clinical study compared morphologic and functional changes of cones after vitrectomy for macula-off retinal detachment. DESIGN: Prospective, fellow-eye comparative case series. METHODS: StudyPopulation: Five eyes after vitrectomy with gas for macula-off retinal detachment (retinal detachment eyes, RDE) and 5 healthy fellow eyes (HFE) of 5 patients (mean age 59.8 years, macula-off duration 0.5 days to 5.5 days). ObservationProcedures: Eyes were examined with adaptive-optics optical coherence tomography (AO-OCT), spectral-domain OCT (SDOCT), and microperimetry (MP) at 6 (baseline, BL) and 56 weeks (follow-up, FUP) after 23 gauge pars plana vitrectomy and SF6 gas tamponade. Eight corresponding regions at foveal eccentricities of 2.5° (ecc 2.5°) and 6.5° (ecc 6.5°) were analyzed in every eye. AO-OCT en face images and SD-OCT B-scans were graded regarding irregularity and loss of photoreceptor signals ranging from none to severe changes. The number of detectable cones at height of the inner-outer segment junction (IS/OS) and cone outer segment tips (COST) was counted manually in AO-OCT images. MP with a custom grid was used to assess retinal sensitivity at these locations. MainOutcomeMeasures: Cone density, cone pattern regularity and signal attenuation, retinal sensitivity. RESULTS: In comparison to HFE, RDE showed highly irregular cone patterns in AO-OCT and irregular outer retinal bands in SDOCT. Despite significant improvement of cone pattern regularity compared to BL (P < .001), 63% of AO images showed remaining cone pattern irregularity and 45.5% of SDOCT B-scans showed severe signal reduction at FUP. In HFE, mean cone density retrieved from IS/OS and COST remained around 20,000/mm2 (ecc 2.5°) and 16,000/mm2 (ecc 6.5°) at BL and FUP. Cone density of RDE was significantly reduced and ranged between 200/mm2 and 15,600/mm2 (P < .001) at BL. Despite improvement at FUP (P < .001), mean cone density at IS/OS and COST was still lower compared to HFE and ranged between 7790 and 9555 cones/mm2 (P < .001). Mean retinal sensitivity of all measured locations remained 18 dB in HFE and was significantly lower in RDE, with 14.30 dB at BL and 14.64 dB at FUP. Both SDOCT grading and microperimetry sensitivity showed strong correlation with AO-OCT grading and cone density (rho values > 0.750). CONCLUSIONS: The combination of AO-OCT, SDOCT, and microperimetry is a powerful tool to capture cone regeneration after vitreoretinal surgery. Our study shows that cone morphology and function improve within 56 weeks after RD surgery but structural and functional impairment is still present.

Semi-automated quantification of geographic atrophy with blue-light autofluorescence and spectral-domain optical coherence tomography: a comparison between the region finder and the advanced retinal pigment epithelium tool in the clinical setting.

PURPOSE: To compare inter- and intraobserver reliability and intermodality agreement on quantification of geographic atrophy, using two routinely available quantification tools, based on blue-light fundus autofluorescence (BAF) and spectral-domain optical coherence tomography (SD-OCT). METHODS: Quantifications of atrophic lesions within the central 5 mm of 30 eyes from 30 patients (mean age: 76.1 years) were independently performed by two clinicians on BAF images using the region finder (RF; Heidelberg Engineering) and on SD-OCT using the advanced retinal pigment epithelium tool (ARPET; Carl Zeiss Meditec) at baseline and follow-up (mean interval: 336 days). Inter- and intraobserver reliability was determined by intraclass correlation coefficients (ICC) and Bland-Altmann plots. Additionally, graders rated the experienced difficulty of each measurement. RESULTS: Intraclass correlation coefficients (ICC) showed excellent inter- and intraobserver reliability with values between 0.994 and 0.998 for RF and slightly higher values for ARPET of 0.997 and 0.999. Bland-Altman plots showed smaller variability for ARPET. Mean interobserver differences (95% CI) for size measurements were -0.11 (-0.27; 0.05) (baseline) and -0.05 mm² (-0.18; 0.08) (follow-up) for RF and -0.04 (-0.14; 0.06) and -0.06 mm² (-0.14; 0.02) for ARPET. Measurements of lesions were on average 0.57 mm² (0.35; 0.79) or 7.6% larger in ARPET. Lesion size between graders did not differ significantly. There was no statistically significant difference in relative enlargement rates between methods. There was poor to moderate agreement between graders when rating the experienced difficulty of each measurement. CONCLUSION: Semi-automated analysis of geographic atrophy with RF and ARPET is equally reliable and reproducible in clinical settings, despite both algorithms require frequent adjustment by users. The ARPET restricts size measurements to the central 5 mm, which limits its ability to fully track GA progression. Results of both tools are not interchangeable as measurements with ARPET result in larger lesion sizes.