Duncan Jacque L, Zhang Yuhua, Gandhi Jarel, Nakanishi Chiaki, Othman Mohammad, Branham Kari E H, Swaroop Anand, Roorda Austin
Department of Ophthalmology, University of California, San Francisco School of Medicine, San Francisco, California 94143-0730, USA.
Invest Ophthalmol Vis Sci. 2007 Jul;48(7):3283-91. doi: 10.1167/iovs.06-1422.
To investigate macular photoreceptor structure in patients with inherited retinal degeneration using high-resolution images and to correlate the findings with clinical phenotypes and genetic mutations.
Adaptive optics scanning laser ophthalmoscopy (AOSLO) images of photoreceptors were obtained in 16 eyes: five with retinitis pigmentosa (RP), three with cone-rod dystrophy (CRD), and eight without retinal disease. A quadratic model was used to illustrate cone spacing as a function of retinal eccentricity. Cone spacing at 1 degrees eccentricity was compared with standard measures of central visual function, including best-corrected visual acuity (BCVA), foveal threshold, and multifocal electroretinogram (mfERG) amplitude and timing. Intervisit variations were studied in one patient with RP and one patient with CRD. Screening of candidate disease genes identified mutations in two patients, one with RP (a rhodopsin mutation) and the other with CRD (a novel RPGR-ORF15 mutation).
Cone spacing values were significantly different from normal for patients with RP (P = 0.01) and CRD (P < 0.0001) and demonstrated a statistically significant correlation with foveal threshold (P = 0.0003), BCVA (P = 0.01), and mfERG amplitude (P = 0.008). Although many RP patients showed normal cone spacing within 1 degrees of fixation, cones could not be unambiguously identified in several retinal regions. Cone spacing increased in all CRD patients, even those with early disease. Little variation was observed in cone spacing measured during two sessions fewer than 8 days apart.
AOSLO images can be used to study macular cones with high resolution in patients with retinal degeneration. The authors present the first report of cone structure in vivo in patients with mutations in rhodopsin and RPGR-ORF15 and show that macular cones display distinct characteristics, depending on the underlying disease. AOSLO imaging, therefore, can provide new insight into possible mechanisms of cone vision loss in patients with retinal degeneration.
利用高分辨率图像研究遗传性视网膜变性患者的黄斑光感受器结构，并将研究结果与临床表型和基因突变相关联。
获取了16只眼睛的光感受器自适应光学扫描激光检眼镜（AOSLO）图像：5只患有视网膜色素变性（RP），3只患有锥杆营养不良（CRD），8只没有视网膜疾病。使用二次模型来说明视锥细胞间距与视网膜离心率的函数关系。将1度离心率处的视锥细胞间距与中心视觉功能的标准测量值进行比较，包括最佳矫正视力（BCVA）、黄斑阈值以及多焦视网膜电图（mfERG）的振幅和时间。对1例RP患者和1例CRD患者进行了不同时间点的变化研究。对候选疾病基因进行筛查，在2例患者中发现了突变，1例RP患者（视紫红质突变），另1例CRD患者（新型RPGR-ORF15突变）。
RP患者（P = 0.01）和CRD患者（P < 0.0001）的视锥细胞间距值与正常情况有显著差异，并且与黄斑阈值（P = 0.0003）、BCVA（P = 0.01）和mfERG振幅（P = 0.008）具有统计学上的显著相关性。尽管许多RP患者在注视点1度范围内视锥细胞间距正常，但在几个视网膜区域无法明确识别视锥细胞。所有CRD患者的视锥细胞间距均增加，即使是疾病早期的患者。在间隔少于8天的两次检查中测量的视锥细胞间距变化很小。
AOSLO图像可用于高分辨率研究视网膜变性患者的黄斑视锥细胞。作者首次报告了视紫红质和RPGR-ORF15突变患者体内视锥细胞结构，并表明黄斑视锥细胞根据潜在疾病表现出不同特征。因此，AOSLO成像可为视网膜变性患者视锥细胞视力丧失的可能机制提供新的见解。
