Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, Peoples Republic of China.
Ophthalmology. 2010 Dec;117(12):2337-44. doi: 10.1016/j.ophtha.2010.04.002. Epub 2010 Aug 3.
To characterize the distribution pattern, angular width, and area of retinal nerve fiber layer (RNFL) defects in glaucoma using spectral-domain optical coherence tomography (OCT).
Prospective, cross-sectional study.
We included 113 normal subjects and 116 glaucoma patients.
One eye from each individual was randomly selected for Cirrus HD-OCT (Carl Zeiss Meditec Inc., Dublin, CA) RNFL imaging of the 6 × 6-mm² parapapillary region. The RNFL defects were identified in the RNFL thickness deviation map as superpixels coded in red. The angular location and the angular width of RNFL defects were measured. The proportion of area with RNFL measurements within the normal ranges in the RNFL thickness deviation map was expressed as the RNFL area index (RAI): 1 - [area of superpixels coded in red/(6 × 6 - optic disc and parapapillary atrophic area)]. The diagnostic performance between RAI and average RNFL thickness was compared with the area under the receiver operating characteristic curve after adjusting refraction, signal strength, optic disc, and parapapillary atrophic areas.
Frequency distribution profiles and distribution patterns of RNFL defects, diagnostic sensitivity and specificity of RAI, and average RNFL thickness.
The RNFL defects in glaucoma were most frequently found at the inferotemporal meridian at 284° (80.4%), followed by the superotemporal meridians at 73° (54.2%). The respective proportions of localized (angular width ≤ 30°) and diffuse (angular width > 30°) RNFL defects were 11.4% and 70.5% in mild glaucoma (MD ≥ 6 dB), and 4.2% and 94.5% in moderate to advanced glaucoma (MD < -6 dB). The RAI was 90.2 ± 6.4% and 83.6 ± 7.4% in the mild and moderate to advanced glaucoma groups, respectively. At a specificity of 90.0%, the respective diagnostic sensitivity of RAI and average RNFL thickness was 95.7% (95% confidence interval, 92.2-99.1%) and 94.0% (90.1-99.1%).
Analysis of the pattern of RNFL defects with spectral domain OCT imaging offers important insights in understanding the characteristics of RNFL damage. As RNFL defects expand in size as the disease progresses, measurement of the angular width and area of RNFL defects can provide an additional dimension for evaluation of glaucoma.
利用频域光相干断层扫描（OCT）描述青光眼患者的视网膜神经纤维层（RNFL）缺损的分布模式、角宽度和面积。
前瞻性、横断面研究。
我们纳入了 113 名正常受试者和 116 名青光眼患者。
每位患者的一只眼随机接受 Cirrus HD-OCT（Carl Zeiss Meditec Inc.，Dublin，CA）6×6mm²视盘旁区域的 RNFL 成像。在 RNFL 厚度偏差图中将编码为红色的超像素识别为 RNFL 缺损。测量 RNFL 缺损的角位置和角宽度。RNFL 厚度偏差图中 RNFL 测量值在正常范围内的面积比例表示为 RNFL 面积指数（RAI）：1-[编码为红色的超像素面积/（6×6-视盘和视盘旁萎缩区）]。通过调整屈光、信号强度、视盘和视盘旁萎缩区后，比较 RAI 和平均 RNFL 厚度的诊断性能。
RNFL 缺损的频率分布特征和分布模式、RAI 和平均 RNFL 厚度的诊断灵敏度和特异性。
青光眼患者的 RNFL 缺损最常发生在 284°的下颞子午线（80.4%），其次是 73°的上颞子午线（54.2%）。局限性（角宽度≤30°）和弥漫性（角宽度>30°）RNFL 缺损在轻度青光眼（MD≥6dB）中的比例分别为 11.4%和 70.5%，在中重度青光眼（MD<-6dB）中的比例分别为 4.2%和 94.5%。轻度和中重度青光眼患者的 RAI 分别为 90.2±6.4%和 83.6±7.4%。特异性为 90.0%时，RAI 和平均 RNFL 厚度的诊断灵敏度分别为 95.7%（95%置信区间，92.2%-99.1%）和 94.0%（90.1%-99.1%）。
使用频域 OCT 成像分析 RNFL 缺损模式可深入了解 RNFL 损伤的特征。随着疾病的进展，RNFL 缺损的大小逐渐扩大，测量 RNFL 缺损的角宽度和面积可为评估青光眼提供另一个维度。
