Sidek S, Ramli N, Rahmat K, Ramli N M, Abdulrahman F, Tan L K
Department of Biomedical Imaging, University Malaya, Research Imaging Centre, Faculty of Medicine, University Malaya, Malaysia; Medical Imaging Unit, Faculty of Medicine, Universiti Teknologi MARA, Selangor, Malaysia.
Department of Biomedical Imaging, University Malaya, Research Imaging Centre, Faculty of Medicine, University Malaya, Malaysia.
Eur J Radiol. 2014 Aug;83(8):1437-41. doi: 10.1016/j.ejrad.2014.05.014. Epub 2014 May 16.
To evaluate whether MR diffusion tensor imaging (DTI) of the optic nerve and optic radiation in glaucoma patients provides parameters to discriminate between mild and severe glaucoma and to determine whether DTI derived indices correlate with retinal nerve fibre layer (RNFL) thickness.
3-Tesla DTI was performed on 90 subjects (30 normal, 30 mild glaucoma and 30 severe glaucoma subjects) and the FA and MD of the optic nerve and optic radiation were measured. The categorisation into mild and severe glaucoma was done using the Hodapp-Parrish-Anderson (HPA) classification. RNFL thickness was also assessed on all subjects using OCT. Receiver operating characteristic (ROC) analysis and Spearman's correlation coefficient was carried out.
FA and MD values in the optic nerve and optic radiation decreased and increased respectively as the disease progressed. FA at the optic nerve had the highest sensitivity (87%) and specificity (80%). FA values displayed the strongest correlation with RNFL thickness in the optic nerve (r=0.684, p ≤ 0.001) while MD at the optic radiation showed the weakest correlation with RNFL thickness (r=-0.360, p ≤ 0.001).
The high sensitivity and specificity of DTI-derived FA values in the optic nerve and the strong correlation between DTI-FA and RNFL thickness suggest that these parameters could serve as indicators of disease severity.
评估青光眼患者视神经和视辐射的磁共振扩散张量成像（DTI）是否能提供区分轻度和重度青光眼的参数，并确定DTI衍生指标是否与视网膜神经纤维层（RNFL）厚度相关。
对90名受试者（30名正常人、30名轻度青光眼患者和30名重度青光眼患者）进行3特斯拉DTI检查，测量视神经和视辐射的FA和MD值。采用霍达普 - 帕里什 - 安德森（HPA）分类法将青光眼分为轻度和重度。所有受试者均使用光学相干断层扫描（OCT）评估RNFL厚度。进行受试者操作特征（ROC）分析和斯皮尔曼相关系数分析。
随着疾病进展，视神经和视辐射的FA值降低，MD值升高。视神经处的FA具有最高的敏感性（87%）和特异性（80%）。视神经处的FA值与RNFL厚度的相关性最强（r = 0.684，p≤0.001），而视辐射处的MD与RNFL厚度的相关性最弱（r = -0.360，p≤0.001）。
DTI衍生的视神经FA值具有高敏感性和特异性，且DTI - FA与RNFL厚度之间具有强相关性，表明这些参数可作为疾病严重程度的指标。
