HIV相关神经认知功能障碍综合征（HAND）临床前期是指无或轻微临床症状但已有HAND病理生理改变的最早阶段。如何运用影像学标记物识别和诊断HAND临床前期成为HAND研究的前沿。HAND是研究临床前期脑损伤影像学标记物最理想的研究对象。本课题拟以中国HIV患者（n=50）无症状（临床前期）和轻度认知功能障碍（n=50）为研究对象，将HAND的研究重点由传统的症状期前移到临床前期；入组匹配健康正常人（n=50）作为对照组；进行非侵入性结构及功能MRI成像检查和临床、神经、心理认知、行为、CD4计数、CD4/CD8及QUIN进行检查，每年随访一次，以探索HAND临床前期的基于磁共振多模态技术的脑形态、结构、功能、代谢及动态变化规律，明确HAND临床前期有明显与临床相关生物标记物，以期得到一组对HAND临床前期有诊断价值的指标。本项目的实施将为HAND早期诊断和干预提供科学依据。

Preclinical stage of HIV associated neurocognitive disorders (HAND) is the earliest stage performing with no clinical symptoms but already with pathophysiological changes. The identification and diagnosis of the preclinical HAND using imaging marker have been one of the research frontiers.HAND is identified as the most ideal subject for imaging research on brain damage during preclinical HAND. This project intends to employ a group of HIV patients without clinical symptoms (50 cases) and another group of HIV patients with mild cognitive disorder symptoms (50 cases) as the research subjects, moving the attention from the traditional symptomatic stage to the preclinical stage. 50 healthy volunteers are enrolled as the control group. Measurements of non-invasive structural and functional MRI, neuropsychological cognition, behavior, CD4 T cell counts , ratio of CD4 to CD8 T cell counts and QUIN are taken once a year. Aim to survey the dynamic discipline of morphological, structural, functional and metabolic changes on brain damage during different periods and to explore the effective MRI makers in the diagnosis of HIVrelated early brain damage. This project facilitates to provide scientific evidence on the early diagnosis of HIV infected brain damage.