Clinical correlation between retinal sensitivity and foveal thickness in retinitis pigmentosa patients

To investigate the relationship between retinal structure and retinal sensitivity comparing data obtained using spectral-domain optical coherence tomography (SD-OCT) and microperimetry in retinitis pigmentosa (RP) and healthy patients.

A total of 49 patients (98 eyes) with RP were divided into 4 groups according to the OCT findings: group A, patients with no macular changes; group B, patients with cystoid macular edema (CME); group C, patients with vitreomacular traction (VMT); group D, patients with retinal thinning. As a control group, we enrolled 27 healthy subjects. All subjects underwent a complete ophthalmologic examination, including SD-OCT and microperimetry. For the statistical analysis, Pearson correlation test and linear regression analysis were used. A p value <0.05 was considered statistically significant.

We did not find any significant difference in best-corrected visual acuity (BCVA), foveal thickness, or retinal sensitivity between group A and the healthy subjects (p>0.05). In group B, linear regression of logMAR versus foveal thickness and retinal sensitivity versus foveal thickness gave r values of 0.931 and 0.786, respectively. In group C, r values were 0.786 and 0.842, respectively, while in group D they were 0.816 and 0.795.

This article shows the first application of the new microperimeter MP3 in patients with RP, which has proven to be very sensitive in detecting functional abnormalities in all the patients. Future studies should investigate the relationships among photoreceptor cell loss, retinal sensitivity, and fixation in patients with RP.