Yun Chang-Soo, Sohn Chul-Ho, Yeon Jehyeong, Chung Kun-Jin, Min Byong-Ji, Yun Chang-Ho, Han Bong Soo
Department of Radiation Convergence Engineering, College of Software and Digital Healthcare Convergence, Yonsei University, Wonju 26493, Republic of Korea.
Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 03080, Republic of Korea.
Diagnostics (Basel). 2025 Jul 16;15(14):1798. doi: 10.3390/diagnostics15141798.
: The glymphatic system plays a crucial role in clearing brain metabolic waste, and its dysfunction has been correlated to various neurological disorders. The Diffusion Tensor Imaging Analysis Along the Perivascular Space (DTI-ALPS) index has been proposed as a non-invasive marker of glymphatic function by measuring diffusivity along perivascular spaces; however, its sensitivity to sleep-related changes in glymphatic activity has not yet been validated. This study aimed to evaluate the feasibility of using the DTI-ALPS index as a quantitative marker of dynamic glymphatic activity during sleep. : Diffusion tensor imaging (DTI) data were obtained from 12 healthy male participants (age = 24.44 ± 2.5 years; Pittsburgh Sleep Quality Index (PSQI) < 5), once while awake and 16 times during sleep, following 24 h sleep deprivation and administration of 10 mg zolpidem. Simultaneous MR-compatible electroencephalography was used to determine whether the subject was asleep or awake. DTI preprocessing included eddy current correction and tensor fitting. The DTI-ALPS index was calculated from nine regions of interest in projection and association areas aligned to standard space. The final analysis included nine participants (age = 24.56 ± 2.74 years; PSQI < 5) who maintained a continuous sleep state for 1 h without awakening. : Among nine ROI pairs, three showed significant increases in the DTI-ALPS index during sleep compared to wakefulness (Friedman test; = 0.027, 0.029, 0.034). These ROIs showed changes at 14, 19, and 25 min after sleep induction, with FDR-corrected -values of 0.024, 0.018, and 0.018, respectively. : This study demonstrated a statistically significant increase in the DTI-ALPS index within 30 min after sleep induction through time-series DTI analysis during wakefulness and sleep, supporting its potential as a biomarker reflecting glymphatic activity.
类淋巴系统在清除脑代谢废物方面起着关键作用，其功能障碍与多种神经疾病相关。沿血管周围间隙的扩散张量成像分析（DTI-ALPS）指数已被提议作为通过测量沿血管周围间隙的扩散率来评估类淋巴功能的非侵入性标志物；然而，其对类淋巴活动中与睡眠相关变化的敏感性尚未得到验证。本研究旨在评估使用DTI-ALPS指数作为睡眠期间动态类淋巴活动定量标志物的可行性。：从12名健康男性参与者（年龄=24.44±2.5岁；匹兹堡睡眠质量指数（PSQI）<5）获取扩散张量成像（DTI）数据，一次在清醒时，在睡眠期间获取16次，在24小时睡眠剥夺和给予10毫克唑吡坦后。使用同时兼容磁共振的脑电图来确定受试者是睡着还是醒着。DTI预处理包括涡流校正和张量拟合。DTI-ALPS指数由与标准空间对齐的投射和联合区域中的九个感兴趣区域计算得出。最终分析包括九名参与者（年龄=24.56±2.74岁；PSQI<5），他们保持连续睡眠状态1小时未觉醒。：在九个感兴趣区域对中，与清醒相比，三个在睡眠期间显示DTI-ALPS指数显著增加（Friedman检验；=0.027、0.029、0.034）。这些感兴趣区域在睡眠诱导后14、19和25分钟出现变化，经FDR校正的P值分别为0.024、0.018和0.018。：本研究通过在清醒和睡眠期间进行时间序列DTI分析，证明睡眠诱导后30分钟内DTI-ALPS指数有统计学显著增加，支持其作为反映类淋巴活动生物标志物的潜力。
