弥漫性中线胶质瘤H3K27M突变型的CT及MRI表现

CT and MRI characteristics of diffuse midline gliomas with H3K27M mutation

目的探讨弥漫性中线胶质瘤H3K27M突变型的CT及MRI表现,提高对该病的认识。方法选取经手术病理证实的弥漫性中线胶质瘤H3K27M突变型8例;男性5例,女性3例,年龄9~48岁,平均年龄24岁;8例均行MRI检查,3例同时行CT检查。结果8例弥漫性中线胶质瘤中5例位于丘脑,2例位于脑干,1例位于胼胝体;病灶直径平均约(4.92±0.91)cm;6例形态不规则,呈分叶状改变,边界不清,2例形态规则,边界清楚;CT平扫呈等低密度,内见斑片状囊变或坏死,1例病灶内见斑片状高密度出血;MRI肿瘤呈囊实性,实性部分T1WI呈等-低信号、T2WI呈稍高-高信号,DWI信号略增高,囊变成分呈明显T1WI低、T2WI高信号表现,出血成分T1WI、T2WI均呈高信号,增强后5例病灶呈轻中度强化;3例病灶呈明显花环样强化,类似高级别胶质瘤。结论弥漫性中线胶质瘤,H3K27M突变型的影像学表现多样,但结合病灶的发病部位以及发病年龄,有助于提高该病的诊断。

Objective To evaluate CT and MRI characteristics of Diffuse Midline Gliomas with H3K27M mutation,in order to improve the knowledge of this disease.Methods We retrospectively analyzed 8 cases of diffuse midline gliomas proved by pathology,with 5 males,3 females,age between 9 and 48 years.The mean age was 24 years old.All patients underwent conventional MRI examination,3 patients also underwent CT examination.Results Of 8 cases,5 located in thalamus,3 located in brainstem,and 1 located in the corpus callosum;The average diameter was(4.92±0.91)cm;6 cases had irregular and lobulated shape,with unclear boundary,2 cases had regular shape,sharply marginated;CT imaging showed iso-low density,variegated cystic degeneration or necrosis,1 case had variegated high-density hemorrhage.On MRI,the solid component showed isointense or slightly-low signal on T1WI,slightly-high or high signal on T2WI,DWI showed slightly-high signal;cystic degeneration or necrosis showed significantly lower signal on T1WI,and significantly higher signal on T2WI;bleeding components showed high signal both on T1WI and T2WI;Contrast enhanced MRI showed heterogeneous enhancement,5 cases showed mild enhancement,3 cases showed ring-like enhancement,similar to high grade glioma.Conclusion Diffuse midline gliomas with H3K27M mutation have various imaging features,combined with the location and age of the lesion,it is helpful for the diagnosis.