Department of Neurology and Experimental Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Experimental and Clinical Research Center, Max Delbrueck Center for Molecular Medicine and Charité - Universitätsmedizin Berlin, Berlin, Germany.
J Neurol Neurosurg Psychiatry. 2024 Mar 13;95(4):366-373. doi: 10.1136/jnnp-2023-332069.
Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis rarely causes visible lesions in conventional MRI, yet advanced imaging detects extensive white matter damage. To improve prognostic capabilities, we evaluate the T1-weighted/T2-weighted (T1w/T2w) ratio, a measure of white matter integrity computable from clinical MRI sequences, in NMDAR encephalitis and examine its associations with cognitive impairment.
T1-weighted and T2-weighted MRI were acquired cross-sectionally at 3 Tesla in 53 patients with NMDAR encephalitis (81% women, mean age 29 years) and 53 matched healthy controls. Quantitative and voxel-wise group differences in T1w/T2w ratios and associations with clinical and neuropsychological outcomes were assessed. P-values were false discovery rate (FDR) adjusted where multiple tests were conducted.
Patients with NMDAR encephalitis had significantly lower T1w/T2w ratios across normal appearing white matter (p=0.009, Hedges' g=-0.51), which was associated with worse verbal episodic memory performance (r=0.39, p=0.005, p(FDR)=0.026). White matter integrity loss was observed in the corticospinal tract, superior longitudinal fascicle, optic radiation and callosal body with medium to large effects (Cohen's d=[0.42-1.17]). In addition, patients showed decreased T1w/T2w ratios in the hippocampus (p=0.002, p(FDR)=0.005, Hedges' g=-0.62), amygdala (p=0.002, p(FDR)=0.005, Hedges' g=-0.63) and thalamus (p=0.010, p(FDR)=0.019, Hedges' g=-0.51).
The T1w/T2w ratio detects microstructural changes in grey and white matter of patients with NMDAR encephalitis that correlate with cognitive performance. Computable from conventional clinical MRI sequences, this measure shows promise in bridging the clinico-radiological dissociation in NMDAR encephalitis and could serve as an imaging outcome measure in clinical trials.
抗 N-甲基-D-天冬氨酸受体（NMDAR）脑炎在常规 MRI 中很少出现可见病变，但高级影像学检查可发现广泛的白质损伤。为了提高预后能力，我们评估了 NMDAR 脑炎患者的 T1 加权/T2 加权（T1w/T2w）比值，这是一种可从临床 MRI 序列计算得出的白质完整性测量值，并研究其与认知障碍的关系。
在 3T 下对 53 名 NMDAR 脑炎患者（81%为女性，平均年龄 29 岁）和 53 名匹配的健康对照者进行 T1 加权和 T2 加权 MRI 横断面采集。评估 T1w/T2w 比值的定量和体素差异以及与临床和神经心理学结局的关系。在进行多次检验时，使用假发现率（FDR）进行了 P 值调整。
NMDAR 脑炎患者的正常表现白质 T1w/T2w 比值明显降低（p=0.009，Hedges' g=-0.51），与言语性情景记忆表现较差相关（r=0.39，p=0.005，p(FDR)=0.026）。在皮质脊髓束、上纵束、视辐射和胼胝体中观察到白质完整性丧失，效应量中等至较大（Cohen's d=[0.42-1.17]）。此外，患者的海马（p=0.002，p(FDR)=0.005，Hedges' g=-0.62）、杏仁核（p=0.002，p(FDR)=0.005，Hedges' g=-0.63）和丘脑（p=0.010，p(FDR)=0.019，Hedges' g=-0.51）的 T1w/T2w 比值也降低。
T1w/T2w 比值可检测出 NMDAR 脑炎患者灰质和白质的微观结构变化，与认知表现相关。可从常规临床 MRI 序列计算得出，该测量值有望弥合 NMDAR 脑炎的临床-影像学差异，并可作为临床试验中的影像学结局测量指标。
