RESUMO
X-linked retinitis pigmentosa (XLRP), a rare form of retinitis pigmentosa (RP), is predominantly caused by mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene. Affected males often present with severe phenotypes and early disease onset. In contrast, female carriers are usually asymptomatic or show stationary phenotypes. Herein, we reported an 8-year-old female carrier, a daughter of a confirmed RP father with RPGR mutation, with an early onset of progressive cone-rod pattern retinal dystrophy. Additionally, the carrier experienced visual snow-like symptom as long as she recalled. Ophthalmological examination showed the reduction of visual acuity and attenuation of photoreceptor functions since the age of 5 years. Further analysis revealed a heterozygous pathogenic variant of the RPGR gene and a random X-inactivation pattern. Although she harboured an identical RPGR variant as the father, there were phenotypic intrafamilial variations. The information on the variety of genotypic and phenotypic presentations in XLRP carriers is essential for further diagnosis, management, and monitoring of these cases, including the design of future gene therapy trials.
RESUMO
OBJECTIVE: To examine subfoveal choroidal thickness (SFCT) in Thai population using enhanced depth imaging spectral- domain optical coherence tomography (EDI-OCT) and to study its correlation with foveal retinal pigment epithelium thickness (FRPE), central neurosensory retinal thickness (CNRT), age, and refraction. MATERIAL AND METHOD: Four hundred eighty eyes from 240 subjects without glaucoma, retinal, or choroidal diseases underwent scanning of the retina and choroid using EDI-OCT SFCT FRPE, and CNRT measurements were based on the 1:1 micron images and wereperformed by two independent observers. The reliability ofmeasurements between the observers was evaluated by intraclass correlation coefficient (ICC). The correlations of SFCT with FRPE, CNRT, age, and refractive error were analyzed RESULTS: The mean age of the subjects was 36.22 years (range 20-81years). The means (95% reference intervals) of SFCT, CNRT andFRPE were 294.02 µm (137.14-450.90 µm), 174.22 µm (141.82-206.62 µm), and 41.94 µm (34.65-49.23 µm), respectively. SFCT and CNRThad excellent reliability between the two observers [ICC = 0.947 (95% CI, 0.918-0.963) and 0.929 (95% CI, 0.906-0.945), respectively], while FRPE showed good reliability [ICC = 0. 729 (95% CI, 0.637-0.793)]. SFCT had a low positive correlation with FRPE (r = 0.179, p<0. 0001) but not with CNRT (p = 0.317). SFCT showed a positive correlation with refraction (r = 0.338, p<0.0001) and a negative correlation with age (r = -0.166, p<0.0001). Regression analysis suggested that the SFCT decreased by 12.23 pm per one decade oflife and by 11.42 pm per one diopter of myopia. CONCLUSION: Normal values of SFCT in Thai population were obtained SFCT significantly decreased with older age and higher myopia. SFCT was associated with FRPE, reflecting the same vascular supply of the choroid and retinal pigment epithelium. When measured with our technique based on the 1:1 micron images, the reliability ofSFCT measurement was very high despite highly morphologic inter-individual variations.
