Kiriko Hirooka1, Michiyuki Saito2, Yui Yamashita1, Yuki Hashimoto3, Nobuhiro Terao4, Hideki Koizumi4, Kousuke Noda1, Susumu Ishida1. 1. Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan. 2. Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan. s.michiyuki@med.hokudai.ac.jp. 3. Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, Fukuoka, Japan. 4. Department of Ophthalmology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan.
Abstract
PURPOSE: Asymmetric dilated vortex vein (ADVV) observed in eyes with pachychoroid spectrum diseases is thought to be due to congestion of choroidal blood flow. The purpose of this study was to quantitatively investigate the blood flow velocity of ADVV using laser speckle flowgraphy (LSFG). STUDY DESIGN: Retrospective case series. METHODS: This was a retrospective case series with 23 eyes of 18 patients with ADVV on en-face OCT. A pair of choroidal veins from ADVV side (defined as ADVV vein) and non-ADVV side (defined as non-ADVV vein) was selected in each eye under the following criteria: (i) equivalent proximity to the deviated watershed, (ii) does not overlap with retinal blood vessels in the en-face OCT image, (iii) has approximately the same blood vessel diameter. Rubber bands were placed on the selected choroidal veins on the LSFG color map. Mean blur rate (MBR) values of ADVV and non-ADVV veins were statistically compared. RESULTS: The average MBR was 10.11 ± 1.9 in the ADVV veins and 13.49 ± 6.2 in the non-ADVV veins, showing significantly lower values in the ADVV veins (P = 0.03). The blood vessel diameter of the ADVV was 10.26 ± 3.0 and in the non-ADVV veins, 10.63 ± 2.9 pixels; not significantly different (P = 0.66). The distance from the deviated watershed to the ADVV was 53.3 ± 24.8 and to the non-ADVV veins, 46.80 ± 20.3 pixels; not significantly different (P = 0.41). CONCLUSION: In eyes with ADVV, the blood flow velocity in the ADVV veins was lower than in the non-ADVV veins, suggesting anatomical congestion of ADVV.
PURPOSE: Asymmetric dilated vortex vein (ADVV) observed in eyes with pachychoroid spectrum diseases is thought to be due to congestion of choroidal blood flow. The purpose of this study was to quantitatively investigate the blood flow velocity of ADVV using laser speckle flowgraphy (LSFG). STUDY DESIGN: Retrospective case series. METHODS: This was a retrospective case series with 23 eyes of 18 patients with ADVV on en-face OCT. A pair of choroidal veins from ADVV side (defined as ADVV vein) and non-ADVV side (defined as non-ADVV vein) was selected in each eye under the following criteria: (i) equivalent proximity to the deviated watershed, (ii) does not overlap with retinal blood vessels in the en-face OCT image, (iii) has approximately the same blood vessel diameter. Rubber bands were placed on the selected choroidal veins on the LSFG color map. Mean blur rate (MBR) values of ADVV and non-ADVV veins were statistically compared. RESULTS: The average MBR was 10.11 ± 1.9 in the ADVV veins and 13.49 ± 6.2 in the non-ADVV veins, showing significantly lower values in the ADVV veins (P = 0.03). The blood vessel diameter of the ADVV was 10.26 ± 3.0 and in the non-ADVV veins, 10.63 ± 2.9 pixels; not significantly different (P = 0.66). The distance from the deviated watershed to the ADVV was 53.3 ± 24.8 and to the non-ADVV veins, 46.80 ± 20.3 pixels; not significantly different (P = 0.41). CONCLUSION: In eyes with ADVV, the blood flow velocity in the ADVV veins was lower than in the non-ADVV veins, suggesting anatomical congestion of ADVV.