探讨MRI联合扩散加权成像(DWI)在小脑毛细胞型星形细胞瘤(PA)与血管母细胞瘤(HB)鉴别诊断中的应用价值。

收集2014年1月至2021年3月淮安市肿瘤医院经病理证实的22例PA与23例HB，分析肿瘤的影像特征(大囊小结节、实性、囊内分隔、流空血管、实性部分均匀强化、囊壁强化、瘤周水肿)，获取瘤肿实质区域和对侧正常参照区域的表观扩散系数(ADC)，计算出相对(肿瘤/参照)ADC(rADC)值，比较两组的影像特征及肿瘤的rADC值，应用受试者工作特征曲线分析rADC值鉴别PA与HB的效能。

PA组年龄分布显著小于HB组(t＝－8.28，P<0.01)；HB较PA更易表现出大囊小结节、流空血管及实性部分强化均匀(χ²＝7.03、13.93、10.41，P均<0.01)，而其他影像特征(肿瘤表现为实性、囊内分隔、囊壁强化、瘤周水肿)在两组间无明显差异(P均>0.05)。HB组的rADC值显著高于PA组(t＝－5.65，P<0.01)，rADC值鉴别两者的曲线下面积为0.892，阈值为1.64时的敏感度、特异度分别为82.60%、81.80%。

常规影像特征可有效鉴别HB与PA，同时rADC值可为两者的鉴别诊断提供定量参数。

To investigate the value of MRI combined with diffusion weighted imaging (DWI) in differential diagnosis between cerebellar pilocytic astrocytoma (PA) and hemangioblastoma (HB).

Twenty-two patients with PA and 23 patients with HB confirmed by pathology in Huai′an Cancer Hospital from January 2014 to March 2021 were collected. Imaging features of the tumors (large cysts with small nodules, solid, intracystic separation, empty blood vessels, homogeneous enhancement of solid part, enhancement of cyst wall, peritumoral edema) were analyzed. Apparent diffusion coefficient (ADC) values of the tumor parenchymal area and the contralateral normal reference area were obtained and then relative (tumor/reference) ADC (rADC) values were calculated. Imaging features and rADC values were compared between the two groups. Receiver operating characteristic curve (ROC) was used to analyze the efficacy of rADC value in differentiating PA and HB.

Age distribution of PA group was significantly lower than that of HB group (t=-8.28, P<0.01). Compared with PA, HB was more likely to show large cysts with small nodules, empty blood vessels and homogeneous enhancement of solid part (χ²=7.03, 13.93, 10.41, all P<0.01), while there were no significant differences in other imaging features (solid tumor, intracystic partition, enhancement of cystic wall, peritumoral edema) between the two groups (all P>0.05). The rADC value of HB group was significantly higher than that of PA group (t=-5.65, P<0.01), area under curve (AUC) of the rADC value differentiating the two groups was 0.892, and when the threshold was 1.64, the corresponding sensitivity and specificity were 82.60% and 81.80%, respectively.

Conventional imaging features can effectively distinguish Hb from PA, and rADC value can provide quantitative parameters for their differential diagnosis.