Optical Coherence Tomography Biomarkers of Photoreceptor Degeneration in Retinitis Pigmentosa

Abstract

Purpose: Several parameters on optical coherence tomography (OCT) have been suggested as biomarkers for photoreceptor degeneration in retinitis pigmentosa (RP). This study is to investigate which OCT parameters can serve as the earliest biomarkers in RP.Methods: OCT line scans of the horizontal meridian were conducted in 22 eyes of 22 RP patients and 30 eyes of 30 healthy controls. Longitudinal reflectance profiles were obtained using ImageJ at every 5 pixels. The following parameters on OCT were quantitatively measured: 1) relative optical intensity (ROI) of ellipsoid zone (EZ) and interdigitation zone (IZ); 2) thickness of outer nuclear layer (ONLT), photoreceptor (PRT), inner segment (IST) and outer segment (OST). The variations of these parameters across different regions were analyzed. Results: From fovea to peripheral retina, all the OCT biomarkers declined before disappeared, except IST and IZ-ROI. There was no identifiable declining zone for the IST and IZ-ROI between the normal and disappeared zones. The earliest biomarker was the shortening of OST and reduced IZ-ROI, followed by the shortening of PRT, EZ-ROI, then IST, and finally, ONLT. All these biomarkers had significant correlations with best-corrected visual acuity, except ONLT.Conclusion: In retinitis pigmentosa, EZ-ROI, IZ-ROI, PRT, OST, IST and ONLT are valuable biomarkers of photoreceptor degeneration. OST and IZ-ROI may serve as the earliest biomarkers.

PRPF31 interacts with PRPH2 confirmed by co-immunoprecipitation and co-localization

“…Retinitis pigmentosa (RP) is a group of inherited disorders characterized by photoreceptor and retinal pigment epithelium dystrophy. [1] The patients with RP usually complain of trouble seeing at night and decreasing peripheral vision. Central visual acuity may also be involved in end-stage or severe types.…”