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Yuji Yoshikawa, Takuhei Shoji, Junji Kanno, Hisashi Ibuki, Kimitake Ozaki, Hirokazu Ishii, Hiromi Inami, Kei Shinoda Department of Ophthalmology, Saitama Medical University, Iruma, Saitama, JapanCorrespondence: Kei ShinodaDepartment of Ophthalmology, Saitama Medical University, 350-0495 Morohogo 38, Iruma, Saitama, JapanTel +81 49-276-1250Fax +81 49-295-8002Email shinodak@med.teikyo-u.ac.jpPurpose: Optical coherence tomography angiography (OCTA) allows noninvasive observation of the retinal vasculature, and image analysis can be used to calculate the retinal vessel density and foveal avascular zone (FAZ) area. A previous study showed that macular vessel density and the signal strength index (SSI) of OCTA images increased significantly after cataract surgery. However, the effect of aging on OCTA analysis remains unclear. This study aimed to investigate age-related changes in macular vascularization while excluding the effects of cataracts.Patients and Methods: OCTA imaging of the macula was performed in adult patients who had undergone cataract surgery between February 2018 and May 2019 and in young healthy participants between April 2017 and April 2018.Results: The median (quartiles) age of the overall study population was 59.0 (27.0, 69.0) years, and no severe refractive error was observed (axial length: 24.2 ± 1.3 [mean ± SD] mm; spherical equivalent: 0.75 [− 2.25, 0.00] diopter). When we investigated the relationship between macular vessel density and age after excluding the effects of cataracts, we found that the macular vessel density showed age-related changes even in the absence of the effects of the SSI. However, the FAZ area was not affected by age.Conclusion: Macular vessel density decreased with age, even when the effects of cataracts were excluded. The effects of age and cataracts should be considered when designing studies and interpreting OCTA findings of the retinal vasculature.Keywords: optical coherence tomography angiography, macular vessel density, foveal avascular zone, aging, cataract surgery

Yuji Yoshikawa, Takuhei Shoji, Junji Kanno, Hisashi Ibuki, Kimitake Ozaki, Hirokazu Ishii, Yoshikazu Ichikawa, Itaru Kimura, Kei Shinoda Department of Ophthalmology, Saitama Medical University, Saitama, Japan Purpose: To evaluate microvascular changes in the macular area of eyes with rhegmatogenous retinal detachment (RRD) without macular involvement (macula-on RRD) using swept-source optical coherence tomography angiography (SS-OCTA). Patients and methods: Five patients with macula-on RRD were eligible for analysis. All patients underwent SS-OCTA examination (Triton) for the macular area. The healthy fellow eyes were included as controls. The vessel density (VD) was calculated using binarization, and the foveal avascular zone (FAZ) was measured. The VD and FAZ area were compared between the eyes with RRD and the fellow eyes using the Wilcoxon signed rank test. Results: The patients’ clinical characteristics were as follows: age, 49.0 years (21.0, 54.0) (median [25, 75th percentile]); preoperative best-corrected visual acuity, -0.08 (-0.08, 0.11) for RRD and -0.08 (-0.08, -0.03) for the fellow eye (P=0.50); and axial length, 27.0 (25.1, 28.7) mm for RRD and 27.4 (25.6, 28.5) mm for the fellow eye (P=0.31). The parafoveal VD was not significantly different between the eyes with RRD and the fellow eyes (P=1.00 for the superficial retina andP=0.44 for the whole retina). The FAZ area was also similar for the eyes with RRD and the fellow eyes (P=0.31 for the superficial retina and P=0.13 for the whole retina). Conclusion: The findings of this study suggest that the macular microvasculature remains intact in eyes with macula-on RRD. Keywords: rhegmatogenous retinal detachment, macula, optical coherence tomography angiography, vessel density

Yuji Yoshikawa,1 Takuhei Shoji,1 Junji Kanno,1 Itaru Kimura,1 Masanori Hangai,2 Kei Shinoda1 1Department of Ophthalmology, Saitama Medical University, Saitama, Japan; 2Hangai Eye Institute, Saitama, Japan Purpose: To evaluate the ability of enhanced-depth imaging (EDI) optical coherence tomography angiography (OCTA) to detect vascular signals inside the glaucomatous optic disc.Patients and methods: Ten glaucomatous eyes of 8 subjects and 11 nonglaucomatous eyes of 7 subjects underwent EDI and conventional OCTA for optic disc analysis. The optic disc vessel density (VD) at maximum scan depth (2 mm) was compared between the 2 methods and between glaucomatous and nonglaucomatous eyes. Regression analysis was used to determine the factors affecting disc VD.Results: The median (25th, 75th percentile) of the visual field mean deviation was –20.5 (–25.1, –13.5) dB in glaucoma. The disc VD measured with the EDI method was significantly greater than that measured with the conventional method in glaucoma and nonglaucoma. The disc VD was also significantly lower in glaucoma than in nonglaucoma. The disc VD and mean deviation were significantly and positively correlated in both methods (conventional: R2=0.27, EDI: R2=0.22).Conclusion: The correlation between disc VD and glaucoma severity was comparable between conventional and EDI measurements. Images obtained with EDI-OCTA have the additional benefit of revealing more vascular signals in deeper layers. The disc VD, as determined by both conventional and EDI-OCTA methods, may be an indicator of glaucoma severity. Keywords: optical coherence tomography angiography, enhanced-depth imaging, vessel density, glaucoma severity, mean deviation