Retinal Vascular Abnormalities in Different Types of Inherited Retinal Dystrophy Assessed by Optical Coherence Tomography Angiography
Hamideh Sabbaghi1 , Hamid Ahmadieh2 , Kiana Hassanpour2 *, Narsis Daftarian3 , Sahba Fekti2 , Ramin Nourinia2 , Bahareh Kheiri2
- Ophthalmic Epidemiology Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Ocular Tissue Engineering Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Abstract: To investigate the vascular characteristics in patients with retinitis pigmentosa (RP), Stargadt disease (STGD) and cone rod dystrophy (CRD).
Methods: This comparative cross-sectional study was conducted on 59 patients with different types of IRDs that their information was extracted from the Iranian National Registry of Inherited Retinal Dystrophy (IRDReg®), of whom only patients with genetically confirmed diagnosis of RP, STGD, and CRD were included. Both eyes of 50 age and sex-matched patients without any pathologic diseases were investigated as the healthy control group. All participants underwent the comprehensive visual and ocular examinations as well as retinal imaging by the optical coherence tomography angiography.
Results: A total of 59 patients with IRD diagnosis and 50 age and sex-matched healthy controls were enrolled in the present study. IRD diagnoses were RP in 37 patients (74 eyes), STGD in 13 patients (26 eyes), and CRD in 9 patients (18 eyes). In terms of the gender distribution, 50.5% of our study subjects were female. In superficial capillary plexus (SCP), whole density was 42.89±7.2, 48.3±3.9, 46.2±6.1 in RP, STGD, and CRD, respectively. Whole density was significantly lower in RP patients in comparison to STGD (P< 0.001), CRD (P< 0.037), and healthy controls (P< 0.001). Similarly, fovea, parafovea, and perifovea density was significantly lower in RP group compared to the control group. In Deep capillary plexus (DCP), in RP patients, whole density (41.16±7.39), fovea density (29.56±10.84), parafoveal density (43.3±8.26), and perifovea density (31.31±19.36) were all significantly lower than control group. (all Ps < 0.001) Similar reduction in vessel density was observed in STGD and CRD patients in comparison to the control group. The foveal avascular zone (FAZ) area was larger in RP (0.3047±0.4013), and STGD (0.3712±0.262) patients in comparison to the control group (0.2685±0.1087). However, the difference did not reach statistically significance level.
Conclusion: Our study demonstrated the decreased vessel density in three different IRDs including RP, STGD, and CRD. Since vascular retina could be used in future therapies like gene therapy, further recognition of OCT-A changes in different stages of the disease could hypothetically have therapeutic implications.
