Sex-related differences are present in ocular blood flow in the ONH, but not in the choroid in healthy subjects. We believe that these differences should be considered when interpreting blood flow data in ocular diseases.

These results indicate that the retinal blood flow is reduced in eyes affected by RRD preoperatively, and can recover following successful RRD repair by vitrectomy.

Sex-related differences are present in the systemic and ocular blood flow. However, the cause of the sex-related differences has not been determined. We investigated the ocular blood flow, represented by the mean blur rate (MBR), on the optic nerve head (ONH) determined by laser speckle flowgraphy in 138 males (63.9 ± 8.9 years) and 194 females (63.5 ± 9.4 years). The correlations between the MBR on the ONH and the clinical data were determined. The overall ONH-MBR was significantly higher in females than males (P < 0.001). In addition, the levels of the hemoglobin and hematocrit were significantly lower in females than in males (P < 0.001). The ONH-MBR was negatively and significantly correlated with the levels of the hemoglobin and hematocrit (both, P < 0.001). Multiple regression analyses showed that the sex (β = 0.248, P < 0.001) was an independent factor correlated with the ONH-MBR when the clinical examination data were not included in the analyses. However, when the clinical examination data were included, the hemoglobin level (β = −0.295, P < 0.001) was an independent factor that contributed to the ONH-MBR but the sex was not. We conclude that the sex-related differences in the hemoglobin level and the negative correlation between hemoglobin and the ONH-MBR are the causes of the sex-related differences in the ONH-MBR.

Although scleral buckling is a well-established surgical treatment for rhegmatogenous retinal detachment (RRD), the procedure can reportedly cause problems in the ocular circulation. Segmental scleral bucking without a concomitant encircling procedure was performed on 46 eyes with successfully reattached macula-on RRD. Choroidal blood flow was assessed using laser speckle flowgraphy. Spectral-domain optical coherence tomography was used to image macular regions, to measure the subfoveal choroidal thickness (SFCT), and to calculate the luminal and the stromal areas by the binarization method preoperatively and 1, 4, 8 and 12 weeks postoperatively. Choroidal mean blur rate at the macula did not significantly change, while that at the buckle and unbuckle side significantly reduced at 8 weeks postoperatively in the operated eye (P = 0.007 and P = 0.017, respectively). The SFCT and the luminal area increased temporarily 1 week following surgery in the operated eye (P < 0.001). The trend of SFCT with time coincided with that of the luminal area (P < 0.001). Venous drainage obstruction induced by compression force of scleral buckling leads to SFCT thickening in the acute postoperative phase. The macular choroidal blood flow might be less susceptible because the blood flow at the macula, in contrast to the other areas, does not change following segmental scleral buckling.

Purpose To analyse the relationship between the extent of metamorphopsia and optical coherence tomography (OCT) parameters including the ectopic inner foveal layer (EIFL) in patients with epiretinal membrane (ERM) who underwent pars plana vitrectomy (PPV). Methods This study included 63 eyes of 62 patients who underwent PPV for ERM. Metamorphopsia was assessed by measuring the metamorphopsia score for vertical lines (MV) and metamorphopsia score for horizontal lines (MH) using M‐CHARTS. Central retinal thickness (CRT), EIFL thickness and disruption of outer retinal layers were measured before and after surgery, and the relationship of these parameters with metamorphopsia scores at 3 months after vitrectomy was analysed. Results Preoperative MV correlated with preoperative CRT and EIFL (p = 0.005 and 0.045 respectively). Postoperative MH correlated with preoperative CRT (p = 0.048), while postoperative MV correlated with preoperative CRT and EIFL (p = 0.002 and 0.0006 respectively). Postoperative MH correlated with postoperative CRT and EIFL (p = 0.001 and 0.002 respectively), and postoperative MV also correlated with postoperative CRT and EIFL (p = 0.0008 and < 0.0001 respectively). MH and MV did not correlate with outer retinal layer disruptions, both before and after vitrectomy. When multiple regression analysis was performed on preoperative and postoperative OCT parameters that correlated with postoperative metamorphopsia scores, only postoperative EIFL was identified as an independent factor associated with postoperative MV (p = 0.042). Conclusion When PPV was conducted for ERM, postoperative EIFL was found to be a significant factor associated with postoperative metamorphopsia score.