Optical Coherence Tomography Angiography Studying Vision Recovery Following Success of Macula-Off Retinal Detachment
Authors: Moustafa Mohamed Hussein Mohamed , AbdAlla Tarek Mohamed Mahmoud , Momtaz Hegazy Sherif , Thabet Farweez Yousra Ahmed 
Published: August 2023

Purpose
Correlate anatomical and functional alterations that happen at the macular area and evaluate retinal vasculature precisely at the FAZ area at SCP & DCP following successful retinal reattachment surgery, by utilizing optical coherence tomography angiography, and correlate these results with vision recovery post-operative.

Patients and Methods
A Prospective Observational case control study involved 14 eyes (14 patients) with fresh onset RRD that were successfully reattached with an uneventful intervention (pars plana vitrectomy with silicone oil injection). One, Six and twelve-weeks post-operative, central foveal thickness was measured using OCT and FAZ area was examined by OCTA (Heidelberg Spectralis) and a standard ophthalmological examination with BCVA assessment (Snellen chart converted to LogMar for statistical analysis) were done. Healthy sound eyes of the same patients had been used as a control for comparison.

Results
BCVA was found to be significantly reduced among patients’ group versus the control group throughout all the three follow ups. The patients’s group BCVA showed highly significant statistical improvement overtime with mean ± SD at first, second and third follow ups were recorded using logMar as 1.02 ± 0.22, 0.63 ± 0.28 and 0.51 ± 0.24, respectively. Mean FAZ area/mm2 in both SCP and DCP in patients' group wasn’t significantly bigger than control group along the whole follow up period. SCP FAZ area was always highly significantly larger than the DCP FAZ area. SCP FAZ area of the patients’ group through the 3 follow ups & of the control group were (mean ± SD area/mm2 0.4 ± 0.18, 0.45 ± 0.15, 0.47 ± 0.2 and 0.43 ± 0.15) respectively, which was a non-statistically significant change over the follow up period with a P-value = 0.172. While DCP FAZ area measured (mean ± SD area / mm2 0.29 ± 0.13, 0.31 ± 0.13, 0.33 ± 0.13 and 0.31 ± 0.12, respectively) with a highly significant larger deep FAZ area at the 3rd follow up compared to 1st follow up with P-value = 0.009. Single point CFT, subfield CFT and Paracentral 3mm thickness in all quadrants in all 3 planes of all, inner, and outer retinal layers were found to be significantly thinner in patients’ group versus sound eye group in the 1st follow up. The Patients’ SPCFT was significantly thicker at the 2nd and 3rd follow up comparable to the 1st follow up (mean ± SD SPCFT / µm at 1st, 2nd and 3rd follow up: 159.07 ± 64.96, 176.21 ± 60.22 and 182.29 ± 45.51, respectively, P-value = 0.014). Only subfield CFT of all retinal layers and outer retinal layers were found to be significantly increasing in thickness among the follow up period (mean ± SD subfield CFT of all retinal layers 221.14 ± 45.9, 231.21 ± 41.17 and 237.79 ± 35.92 at 1st, 2nd and 3rd follow up, respectively with P-value = 0.003) (mean ± SD subfield CFT of outer retinal layers 78.5 ± 4.16, 84.43 ± 8.44 and 86.21 ± 6.51 92 at 1st, 2nd and 3rd follow up, respectively with P-value = 0.001). While subfield CFT of inner retinal layer showed a non-significant change in thickness among the follow up period. Neither SCP FAZ nor DCP FAZ were found to be correlated with postoperative BCVA, any of the retinal thickness measurements nor the duration of detachment/ days at any of the 3 follow ups.

Conclusion
BCVA is significantly reduced after RRD in the patient’s group in comparison with the control group which appeared to improve significantly at the 3rd follow up compared to the 1st Follow up. However, this improvement was not found to be correlated to any change in the retinal thickness nor the FAZ area. There were no changes detected affecting the FAZ area of patients with repaired RRD after surgery. SCP FAZ, however, was discovered to be significantly bigger than DCP FAZ among the patients’ and the control groups.