Search

Purpose To investigate the relationships between foveal blood flow as measured by laser speckle flowgraphy (LSFG), the retinal-choroidal structure in enhanced depth imaging-optical coherence tomography (EDI-OCT), and central visual function in patients with retinitis pigmentosa (RP). Methods We studied 52 consecutive typical RP patients ≤50 years old and 21 age- and sex-matched controls. The mean blur rate (MBR), which represents the blood flow volume, was calculated in a 2.4-mm2 area centered on the fovea by LSFG. Subfoveal horizontal EDI-OCT images were recorded, and the choroidal area, choroidal hyporeflective area, and choroidal hyperreflective area were analyzed in the central 2.4-mm-wide region. The central foveal thickness (CFT), subfoveal choroidal thickness (SCT), and ellipsoid zone (EZ) width were also measured. Visual acuity (VA) and retinal sensitivity (Humphrey 10-2 program) were measured in the RP patients. Results The MBR, choroidal area, hyporeflective area, hyperreflective area, and SCT were significantly decreased in the RP patients (all P < 0.001, versus controls). Spearman's rank testing demonstrated no significant correlation between the MBR and the choroidal structural parameters in the RP patients. Decreased MBR was significantly associated with reductions in VA, retinal sensitivity, CFT, and EZ width (all P < 0.05). The choroidal structural parameters did not correlate with central visual function, and the choroidal area, hyperreflective area, and SCT were inversely associated with CFT (all P < 0.05). Conclusions These results demonstrated the divergence between the choroidal structure and blood function, and suggest that decreased choroidal flow, rather than the structural alteration, is closely associated with foveal degeneration in RP.

Purpose Posterior subcapsular cataract (PSC) is a frequent complication in patients with retinitis pigmentosa (RP). The risk factors for PSC formation in RP are largely unknown. The purpose of this study was to investigate the risk factors for PSC. Methods We retrospectively studied a total of 322 eyes of 173 patients who were diagnosed with typical RP. We considered the following possible risk factors for PSC: age, sex, hypertension, diabetes mellitus, high myopia, asthma, history of steroid intake, and aqueous flare. Aqueous flare values were measured consecutively in 2012 and 2013 using a laser flare cell meter. The lens including PSC was examined with a slit lamp after dilation with tropicamide 1% and phenylephrine 2.5%. Results The geometric mean values of aqueous flare and mean values of visual acuity were significantly higher for the RP patients with PSC compared to those without PSC (P = 0.0003, P = 0.0004, respectively). When the aqueous flare values were assessed continuously, each 1-log-transformed increase in flare levels was associated with an elevation of the likelihood of having PSC after multivariable adjustment (odds ratio: 1.71; 95% confidence interval: 1.05-2.77). There were no significant associations of the other possible risk factors with PSC. Conclusions Our analysis demonstrated that elevated aqueous flare is a significant risk factor for PSC formation. This result might provide insights into the association of inflammation and the pathogenesis of PSC formation in RP.

PURPOSE Epiretinal membrane (ERM) is a frequent macular complication in patients with retinitis pigmentosa (RP). The etiology of ERM formation in RP is largely unknown. The purpose of this study was to investigate the association between aqueous flare, a surrogate index of intraocular inflammation, and ERM secondary to RP. METHODS We retrospectively studied a total of 206 eyes of 117 patients who were diagnosed with typical RP. Aqueous flare values were measured consecutively in 2012 and 2013 using a laser flare cell meter. Spectral-domain optical coherence tomography images and fundus photographs taken on the same day of the aqueous flare measurements were analyzed for ERM detection. RESULTS The mean values of aqueous flare, age, and frequency of male sex were significantly higher in the RP patients with ERM compared with the RP patients without ERM (P < 0.0001, P = 0.007, and P = 0.004, respectively). After adjustment for age and sex, the eyes in the highest quartile of aqueous flare had significantly higher odds of having ERM than those in the lowest quartile (odds ratio [OR], 2.68; 95% confidence interval [CI], 1.04-6.93), and the linear trend across flare levels was significant (P = 0.005). In addition, each 1-log-transformed increase in flare values was associated with an elevation of the likelihood of having ERM (OR, 2.59; 95% CI, 1.33-5.06). CONCLUSIONS Our analysis demonstrated that elevated aqueous flare is associated with ERM secondary to RP, suggesting that inflammation may be implicated in the pathogenesis of ERM formation in RP.