Abstract
Purpose :
Sickle cell disease encompasses a spectrum of inherited hemoglobinopathies that have various ophthalmic manifestations, including SCR. WF SS-OCTA is a valuable tool to assess the extra-macular region compared to traditional OCTA. Herein, we aim to study the utility of WF SS-OCTA in SCR.
Methods :
We conducted a single-institution observational study using WF SS-OCTA to obtain 3x3mm, 6x6mm, and 12x12mm scans centered on the fovea. The ARI Network (Zeiss Portal) was used to quantify vascular metrics such as vessel density (VD), vessel skeletonized density (VSD) in superficial (SCP), deep capillary plexus (DCP) and whole retina; and foveal avascular zone (FAZ) area, circularity and perimeter. Mixed-effects multiple regression models adjusting for age were used for statistical analysis.
Results :
The median age was 59 (46-63.3) years. We analyzed 38 control eyes of 20 patients and 20 eyes of 11 patients with SCR: proliferative SCR (PSCR, n=5), non-proliferative SCR (NPSCR, n=9), and no SCR (NSCR, n=6). On 3x3mm scans, the PSCR group had decreased FAZ circularity vs the control (β=-0.15), NSCR (β=-0.15), and NPSCR (β=-0.11) groups (p<0.05). Importantly, the NSCR group had greater FAZ area vs controls (β=0.27, p=0.04). On 6x6mm scans, there was reduced SCP VD (NSCR β=-0.05; NPSCR β=-0.05, PSCR β=-0.04, all p<0.05) and VSD (NSCR β=-2.67; NPSCR β=-2.53, PSCR β=-2.41, all p<0.05) and whole retina VD (NSCR β=-0.04; NPSCR β=-0.04, PSCR β=-0.03, all p<0.05) and VSD (NSCR β=-2.09; NPSCR β=-2.18, PSCR β=-1.96, all p<0.05) for all groups compared to controls. NPSCR eyes also demonstrated reduced DCP VSD (β=-3.66) and VD (β=-0.07) vs controls (p<0.05). There was increased FAZ perimeter for NPSCR (β=1.64) and PSCR (β=1.06) vs controls (p<0.05). FAZ area was also increased for NSCR (β=0.28), NPSCR (β=0.36) vs controls, and NPSCR (β=0.17) vs the PSCR group (all p<0.05). On 12x12 scans, there was increased FAZ area for the NSCR group (β=0.31, p=0.02) vs controls.
Conclusions :
Our results show that in patients with no evidence of SCR, there is an increased FAZ area vs control, suggesting a subclinical disease featuring early retinal capillary dropout. This study demonstrates reduction in VD/VSD and hence the potential benefits of utilizing WF SS-OCTA in SCR. In future, we aim to investigate changes in the periphery and its clinical significance using this imaging technology.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.