Song Xiang-Yuan, Puyang Zhen, Chen Ai-Hua, Zhao Jin, Li Xiao-Jiao, Chen Ya-Ying, Tang Wei-Jun, Zhang Yu-Yan
Department of Ophthalmology, Huashan Hospital, Fudan University, Shanghai, China.
Key Laboratory of Brain Functional Genomics (Ministry of Education), East China Normal University, Shanghai, China.
Front Hum Neurosci. 2018 Oct 22;12:426. doi: 10.3389/fnhum.2018.00426. eCollection 2018.
Ocular hypertension (OHT), the common situation in adult patients in the outpatients, occurs ∼5% worldwide. However, there are still some practical problems in differentiation of OHT with early primary open-angle glaucoma (POAG) using current standard methods. Application of high resolution diffusion tensor imaging (DTI) enables us to the differentiate axonal architecture of visual pathway between POAG and OHT subjects. Among 32 POAG patients recruited (15 OHT and 14 control subjects), 62.5% of glaucoma were in early stage for the current study. All subjects underwent ophthalmological assessments with standard automated perimetry and optical coherence tomography (OCT). DTI was applied to measure fraction anisotropy (FA) and mean diffusivity (MD) of optic tract (OT), lateral geniculate body (LGN) and optic radiation (OR) using voxel-based analysis. Our data demonstrated that FA values of bilateral OR in POAG were significantly lower in the right or left than that of OHT patients (left OR: 0.51 ± 0.04 vs. 0.54 ± 0.03, < 0.05; right OR: 0.51 ± 0.05 vs. 0.54 ± 0.03, < 0.05). In right LGN, MD values were higher in POAG patients compared with OHT subjects (9.81 ± 1.45 vs. 8.23 ± 0.62, < 0.05). However, no significant difference of all of the DTI parameters was observed between OHT and control subjects. DTI parameters in POAG patients were positively correlated with morphological and functional measurements ( < 0.05). Vertical cup to disc ratio (VCDR) was correlated with ipsilateral FA of OT ( < 0.05), ipsilateral MD of OT ( < 0.05), ipsilateral MD of LGN ( < 0.05), and contralateral MD of OT ( < 0.05). Mean deviation of visual field (MDVF) was correlated with ipsilateral FA of OT ( < 0.05), ipsilateral MD of OT ( < 0.05), and ipsilateral FA of LGN ( < 0.05). Our study demonstrated that DTI can differentiate POAG from OHT subjects in optic pathway, particularly in early POAG, and DTI parameters can quantify the progression of POAG.
高眼压症（OHT）是门诊成年患者中的常见情况，在全球范围内的发生率约为5%。然而，使用当前的标准方法在鉴别高眼压症与早期原发性开角型青光眼（POAG）时仍存在一些实际问题。高分辨率扩散张量成像（DTI）的应用使我们能够区分POAG患者和高眼压症患者视觉通路的轴突结构。在招募的32例POAG患者（15例高眼压症患者和14例对照受试者）中，62.5%的青光眼患者处于本研究的早期阶段。所有受试者均接受了标准自动视野计和光学相干断层扫描（OCT）的眼科评估。使用基于体素的分析方法，应用DTI测量视束（OT）、外侧膝状体（LGN）和视辐射（OR）的各向异性分数（FA）和平均扩散率（MD）。我们的数据表明，POAG患者双侧OR的FA值在右侧或左侧均显著低于高眼压症患者（左侧OR：0.51±0.04 vs. 0.54±0.03，P<0.05；右侧OR：0.51±0.05 vs. 0.54±0.03，P<0.05）。在右侧LGN中，POAG患者的MD值高于高眼压症受试者（9.81±1.45 vs. 8.23±0.62，P<0.05）。然而，在高眼压症患者和对照受试者之间未观察到所有DTI参数的显著差异。POAG患者的DTI参数与形态学和功能测量值呈正相关（P<0.05）。垂直杯盘比（VCDR）与同侧OT的FA（P<0.05）、同侧OT的MD（P<0.05）、同侧LGN的MD（P<0.05）以及对侧OT的MD（P<0.05）相关。视野平均偏差（MDVF）与同侧OT的FA（P<0.05）、同侧OT的MD（P<0.05）以及同侧LGN的FA（P<0.05）相关。我们的研究表明，DTI能够在视通路中区分POAG患者和高眼压症患者，尤其是在早期POAG中，并且DTI参数能够量化POAG的进展。
