Li Ting, Wang Qian, Yang Bingbing, Qu Xiaoxia, Chen Weiwei, Wang Huaizhou, Wang Ningli, Xian Junfang
Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, China.
Brain Res. 2025 Mar 1;1850:149450. doi: 10.1016/j.brainres.2025.149450. Epub 2025 Jan 8.
Disruption of the glymphatic system plays a vital role in pathogenesis of neurodegeneration in normal tension glaucoma (NTG). We evaluated the impairment of glymphatic system of NTG patients by diffusion tensor image analysis along the perivascular space (DTI-ALPS), and explored the correlation between the ALPS index and dysfunction of visual cortices in resting state. DTI-ALPS was applied to 37 normal controls (NCs) and 37 NTG patients. Multidirectional diffusivity maps and fractional anisotropy (FA) maps were reconstructed to calculate ALPS index. The Amplitude of low-frequency fluctuation (ALFF) in visual cortices (V1-V5) were calculated using resting-state fMRI. Clinical data and ALPS indexes were compared between the groups. Lateralization of ALPS indexes and differences in visual field of two eyes were analyzed. Subsequently, regression analyses between ALPS indexes and mean deviation (MD) values of bilateral eyes and ALFF of visual cortices were performed. The bilateral ALPS indexes of NTG patients decreased significantly. In NCs and NTG patients, ALPS indexes in right hemisphere were lower than that in left hemisphere. The right ALPS indexes of NTG patients were positively correlated with the MD values of the left eyes. In NTG patients, decreased ALFF was detected in right V1 and bilateral V2-5, and the left ALPS indexes were positively correlated with ALFF in bilateral V1, V2, V5, and right V3V area. The ALPS index decreased in NTG patients, correlated with visual defects and ALFF, indicating impairment of the glymphatic system and the potential to be a biomarker in the future.
淋巴系统功能紊乱在正常眼压性青光眼（NTG）神经退行性变的发病机制中起关键作用。我们通过沿血管周围间隙的扩散张量成像分析（DTI-ALPS）评估NTG患者淋巴系统的损害，并探讨ALPS指数与静息状态下视觉皮层功能障碍之间的相关性。对37名正常对照者（NCs）和37名NTG患者应用DTI-ALPS。重建多向扩散图和分数各向异性（FA）图以计算ALPS指数。使用静息态功能磁共振成像计算视觉皮层（V1-V5）的低频波动幅度（ALFF）。比较两组间的临床数据和ALPS指数。分析ALPS指数的偏侧化及双眼视野差异。随后，对ALPS指数与双眼平均偏差（MD）值及视觉皮层ALFF进行回归分析。NTG患者双侧ALPS指数显著降低。在NCs和NTG患者中，右半球的ALPS指数低于左半球。NTG患者的右ALPS指数与左眼的MD值呈正相关。在NTG患者中，右侧V1及双侧V2-5检测到ALFF降低，左侧ALPS指数与双侧V1、V2、V5及右侧V3V区的ALFF呈正相关。NTG患者的ALPS指数降低，与视觉缺陷和ALFF相关，表明淋巴系统受损且未来有可能成为生物标志物。
