本研究的目的是通过沿血管周围空间（ALPS）的扩散张量图像分析，无创地探索胶质瘤中的类淋巴系统（GS）及其与胶质瘤特征和预后的关系。在2015年4月至2021年11月期间，所有经病理证实未接受手术、化疗、放疗或立体定向活检的单半球胶质瘤患者；没有严重的大脑变形；术前接受过常规和先进的全脑扩散加权成像；其数据可用且未泄露的数据均包含在本研究中。还包括接受弥散加权成像的年龄和性别匹配的健康对照（HC）。 ALPS 指数是根据扩散率图计算的，允许对 GS 进行非侵入性分析。所有胶质瘤患者均测量对侧 ALPS 指数，同侧半球无严重变形的胶质瘤患者测量同侧 ALPS 指数。根据肿瘤分级、IDH 基因型、肿瘤和水肿体积以及肿瘤位置比较神经胶质瘤患者和 HC 之间的 ALPS 指数。进一步分析胶质瘤双侧 ALPS 指数与肿瘤特征之间的关联。使用 Kaplan-Meier 生存曲线、对数秩检验以及单变量和多变量 Cox 回归进行生存分析。 91 名单半球胶质瘤患者（33 名女性，平均年龄 46 ± 13 岁）和 59 名年龄和性别匹配的 HC均被纳入本研究。与 HC 组相比，胶质瘤组的同侧 ALPS 指数下降，无论肿瘤分级、IDH 基因型、肿瘤和水肿体积或肿瘤位置如何（p ≤ 0.048），而在高级别、IDH 的胶质瘤中，对侧 ALPS 指数下降野生型，水肿体积较大，肿瘤体积和位置不同（p ≤ 0.009）。无论肿瘤分级、IDH 基因型、肿瘤和水肿体积或肿瘤位置如何，同侧 ALPS 指数均低于对侧 (p ≤ 0.044)。单变量线性回归显示年龄（β = -0.004，p = 0.026）、肿瘤分级（β = -0.114，p = 0.011）和 IDH 基因型（β = 0.120，p = 0.008）与神经胶质瘤中的同侧 ALPS 指数相关。年龄（β = -0.005，p < 0.001），肿瘤分级（β = -0.144，p < 0.001），IDH 基因型（β = 0.154，p < 0.001），肿瘤体积（β = -0.002，p = 0.001），胶质瘤中瘤周水肿体积（β = -0.002，p < 0.001）与对侧 ALPS 指数相关。多变量线性回归显示肿瘤分级（β = -0.125，p = 0.005）与同侧 ALPS 指数独立相关。年龄（β = -0.003，p = 0.022）、IDH 状态（β = 0.132，p = 0.001）和肿瘤体积（β = -0.002，p < 0.001）与对侧 ALPS 指数独立相关。 Kaplan-Meier 分析显示低和高对侧 ALPS 组之间的生存时间不同（log-rank = 10.574，p = 0.001）。单变量 Cox 回归分析表明，对侧 ALPS 指数较低与较短的生存时间相关（HR 0.095，p = 0.005）。多变量 Cox 回归分析显示，IDH 状态是生存的唯一独立因素（HR 0.138，p < 0.001）。胶质瘤中 GS 功能受损，并与肿瘤特征相关，对侧 GS 功能较差与较短的生存时间相关。

The aim of this study was to noninvasively explore the glymphatic system (GS) in glioma and its association with glioma characteristics and prognosis by using diffusion tensor image analysis along the perivascular space (ALPS).In the period from April 2015 to November 2021, all patients with pathologically confirmed unihemispheric glioma who had not undergone surgery, chemotherapy, radiotherapy, or stereotactic biopsy; who did not have severe brain deformation; who had undergone preoperative conventional and advanced whole-brain diffusion-weighted imaging; and whose data were available and uncompromised were included in this study. Age- and sex-matched healthy controls (HCs) who had undergone diffusion-weighted imaging were also included. The ALPS index was calculated based on diffusivity maps, allowing noninvasive analysis of the GS. The contralateral ALPS index was measured in all glioma patients, and the ipsilateral ALPS index was measured in glioma patients without severe deformation of the ipsilateral hemisphere. The ALPS index was compared between glioma patients and HCs according to tumor grade, IDH genotype, tumor and edema volume, and tumor location. The association between the bilateral ALPS index of gliomas and tumor characteristics was further analyzed. Survival analysis was conducted using Kaplan-Meier survival curves with the log-rank test and univariable and multivariable Cox regressions.Ninety-one patients with unihemispheric glioma (33 female, mean age 46 ± 13 years) and 59 age- and sex-matched HCs were included in this study. The ipsilateral ALPS index decreased in the glioma group versus the HC group, regardless of tumor grade, IDH genotype, tumor and edema volume, or tumor location (p ≤ 0.048), whereas the contralateral ALPS index decreased in gliomas with a high grade, IDH wildtype, larger edema volume, different tumor volumes and locations (p ≤ 0.009). The ipsilateral versus contralateral ALPS index was lower regardless of tumor grade, IDH genotype, tumor and edema volume, or tumor location (p ≤ 0.044). Univariable linear regression revealed age (β = -0.004, p = 0.026), tumor grade (β = -0.114, p = 0.011), and IDH genotype (β = 0.120, p = 0.008) were associated with the ipsilateral ALPS index in glioma. Age (β = -0.005, p < 0.001), tumor grade (β = -0.144, p < 0.001), IDH genotype (β = 0.154, p < 0.001), tumor volume (β = -0.002, p = 0.001), and peritumoral edema volume (β = -0.002, p < 0.001) were correlated with the contralateral ALPS index in glioma. Multivariable linear regression revealed that tumor grade (β = -0.125, p = 0.005) was independently associated with the ipsilateral ALPS index. Age (β = -0.003, p = 0.022), IDH status (β = 0.132, p = 0.001), and tumor volume (β = -0.002, p < 0.001) were independently associated with the contralateral ALPS index. Kaplan-Meier analysis showed different survival times between low and high contralateral ALPS groups (log-rank = 10.574, p = 0.001). Univariable Cox regression analysis demonstrated that the lower contralateral ALPS index was related to a shorter survival time (HR 0.095, p = 0.005). Multivariable Cox regression analysis revealed IDH status as the only independent factor for survival (HR 0.138, p < 0.001).GS function was impaired in glioma and correlated with tumor characteristics, and worse contralateral GS function was associated with a shorter survival time.