Steeper Macular Curvature in Eyes With Non-Highly Myopic Retinitis Pigmentosa

Abstract

PURPOSE. A posterior staphyloma has been reported to be present in some eyes with retinitis pigmentosa (RP), and the purpose of this study was to determine the macular curvature of non-highly myopic RP eyes. METHODS. This was a retrospective, observational study. The medical charts of the right eyes of 143 patients with RP and 60 controls whose axial length ranged from 21.5 mm to 26.0 mm were reviewed. The mean curvature of Bruch's membrane within 6 mm of the central macula obtained from the horizontal optical coherence tomographic images were evaluated as the mean macular curvature index (MMCI). The relationships between the MMCI and other clinical factors were assessed. RESULTS. The mean MMCI of RP patients (À13.73 6 9.63 3 10 À5 lm À1) was significantly lower than that of the controls (À6.63 6 5.63 3 10 À5 lm À1). This indicated a deeper concave shape of the macula in RP eyes (P < 0.001). The MMCI was significantly correlated with the age (r ¼ 0.20; P ¼ 0.016) and the axial length (r ¼ À0.24; P ¼ 0.004). Further analysis suggested a nonlinear effect of the ellipsoid zone width on the macular curvature in the RP eyes. CONCLUSIONS. There is a high incidence of steeper macular curvatures even in non-highly myopic RP eyes, and the steepness was also affected by the degree of photoreceptor degeneration.

Longitudinal Changes of Macular Curvature in Patients with Retinitis Pigmentosa

“…In an earlier study, we found a nonlinear relationship between the EZ width and the MMCI; the MMCI was lower in eyes with an EZ width of around 2200 µm, and the MMCI was higher in eyes with shorter or longer EZ widths. 10 Thus, we divided the eyes into three groups according to the EZ width at the baseline; >2000 µm (mild, 42 eyes), between 0 and 2000 µm (moderate, 42 eyes), and no EZ (severe, 23 eyes). Only the mild group had a significant change in the MMCI during the experimental period ( P = 0.011, one-sample t -test).…”

“…The methods to measure the macular curvature in the SD-OCT images have been described in detail. 10 Briefly, each horizontal and vertical SD-OCT image was corrected for the difference in the pixel resolution in the transverse and longitudinal directions. Then, the reflective line corresponding to Bruch's membrane across the fovea (yellow line in Fig.…”

“…1A in Ref. 10 ) was measured quantitatively using MATLAB software (MathWorks, Natick, MA). Eleven to 12 points were marked on the Bruch's membrane line beginning from the center of the fovea, and the marks were separated by 200 pixels (approximately 760 µm) in the SD-OCT images (yellow triangles in Fig.…”

“…In our earlier study, we quantitatively analyzed the macular curvature of 143 patients with RP and reported a high incidence of steeper macular curvatures, including staphylomas, even in RP eyes that are not highly myopic. 10 However, due to the cross-sectional nature of the data collection, the longitudinal changes of the macular curvature were not determined during the course of the retinal degeneration.…”

CoPP-Induced-Induced HO-1 Overexpression Alleviates Photoreceptor Degeneration With Rapid Dynamics: A Therapeutic Molecular Against Retinopathy

“…MNUinduced photoreceptor degeneration is rapidly progressing, while RP is a relatively chronic retinopathy with a much longer course. 1,36 Therefore, the progression rate should be considered as an instinctive disadvantage of the MNU-induced models, as it deviates somewhat from the natural history of human RP.…”