颅内原始神经外胚层肿瘤CT及MRI诊断的临床价值探讨

Clinical Value of CT and MRI in the Diagnosis of Intracranial Primitive Neuroectodermal Tumors

目的分析颅内原始神经外胚层肿瘤的CT及MRI影像特点。方法选择2015年9月至2017年10月期间我院收治的颅内原始神经外胚层肿瘤患者44例,均经MRI及CT检查,总结影像学诊断结果及特征。结果年龄10~20岁的颅内原始神经外胚层肿瘤患者共22例,发病位于幕上34例。幕上患者中,顶叶患者8例,额叶患者4例,颞顶叶患者4例,枕顶叶患者4例,松果体患者2例,丘脑患者8例。肿瘤平均直径:(5.82±1.54)cm。所有患者肿瘤均属单发病灶。圆形肿瘤形态者36例,分叶状肿瘤形态者4例,棱形肿瘤形态者4例。经CT平扫,实性肿瘤呈现稍高密度或者等密度,囊实性肿块型则多为坏死囊变。经MRI扫描,实性肿块型T1WI等、低信号,T2WI呈等、稍高信号,T2FLAIR呈现等、稍高信号。肿瘤囊性成分T1WI呈现出稍高信号、T2FLAIR呈现出低信号,T2WI呈现出低信号,与脑实质的分界较为清楚,增强扫描病灶部分强化。结论颅内原始神经外胚层肿瘤存在一定的影像学检查特征,但特异性较差,在进行诊断时,需结合患者的年龄、肿瘤水肿等实际情况进行综合判断;确诊依赖病理诊断。

Objective To analyze the CT and MRI features of intracranial primitive neuroectodermal tumors.Methods A total of 44 patients with intracranial primitive neuroectodermal tumor were selected from September 2015 to October 2017,all of them underwent MRI and CT examination,and the imaging diagnosis results and characteristics were summarized.Results There were twenty two patients aged 10-20 years with primitive neuroectodermal tumors concluded in the study.There were 34 cases were located supratentorial.Among the supratentorial patients,there were 8 lesions located at parietal lobe,4 lesions located at frontal lobe,4 located at temporal parietal lobe,4 located at occipital parietal lobe,2 located at pineal gland and 8 located at thalamus.The average diameter of tumor was(5.82±1.54)cm.All the tumors were solitary.There were 36 cases with round tumor morphology,4 cases with lobulated tumor morphology and 4 cases with prismatic tumor morphology.On plain CT scan,solid tumors showed slightly high density or equal density,while cystic solid masses were mostly necrotic cystic changes.On MRI scan,solid mass showed iso-intense and hypo-intense on T1WI,iso-intense and slightly hyper-intense on T2WI,iso-intense and slightly hyper-intense on T2 FLAIR.The cystic component of the tumor showed slightly high signal on T1WI,low signal on T2 FLAIR,and low signal on T2WI.The boundary between tumor cystic component and brain parenchyma was clear,and enhanced scanning could help to strengthen part of the tumor.Conclusion Intracranial primitive neuroectodermal tumors have certain imaging features,but the specificity is poor.In the diagnosis,it is necessary to combine the patient's age,tumor edema and other actual conditions for comprehensive judgment.The diagnosis of this disease depends on pathological diagnosis.