MRI和1H-MRS诊断中枢神经细胞瘤

MRI and proton magnetic resonance spectroscopy in diagnosis of central neurocytoma

目的探讨中枢神经细胞瘤(CNC)的MRI和1 H-MRS的特征性表现及其诊断价值。方法回顾性分析12例经手术病理证实的CNC患者的MRI资料,其中8例接受多体素1 H-MRS检查。结果①MRI表现:9例肿瘤位于侧脑室体部前2/3区,3例位于后1/3区;11例以实性为主,1例以囊性为主。6例瘤体内见斑片状钙化;7例见纡曲血管影;7例瘤体与受侵侧脑室壁之间牵拉呈"索条状影"。增强后8例呈不均匀轻-中度强化,2例不均匀明显强化,2例呈环状强化。②DWI及ADC值:10例肿瘤呈稍高或高信号;2例为等或稍低信号。ADC值为(0.76±0.11)×10-3mm2/s。③MRS:8例均表现为胆碱峰(Cho)显著升高,N-乙酰天冬氨酸(NAA)峰显著降低,Cho/NAA升高;4例甘氨酸峰(Gly)在3.55ppm处升高。结论CNC具有较为特异的临床和MRI特征;MRI对于CNC的术前诊断与鉴别诊断具有重要价值;DWI及1H-MRS可从分子水平无创观察肿瘤生化指标和组织代谢情况,有效提高CNC诊断的准确性。

Objective To investigate the features and diagnostic value of MRI and 1H-MRS for central neurocytoma （CNC）. Methods Totally 12 patients with CNC confirmed pathologically underwent routine MRI, among them 8 underwent 1H-MRS examination. All the data were analyzed retrospectively. Results ①MRI findings： The tumors of 9 cases located in the top 2/3 of the lateral ventricle body, 3 cases in the rear 1/3 of the lateral ventricle body. Tumors in 11 cases were mainly solid, tumor of 1 case was mainly cystic. Patchy calcification at the intratumoral of CNC were observed in 6 cases, tortuous vessels were detected in 7 cases, while the lateral ventricle wall was pulled by the tumor and formed cable strip shadows in 7 cases. On enhanced MRI, inhomogeneous light-moderately enhancement of CNC was observed in 8 cases, significantly uneven enhancement was found in 2 cases, while rim-like enhancement was noticed in 2 cases. ②DWI performances and ADC values： On DWI, slightly higher or high signal were observed in 10 cases, while isointense or slightly lower signal were detected in 2 cases. ADC value of CNC was （0.760.11）10-3mm2/s. ③All 8 patients executed MRS showed significant higher choline （Cho） peak and reducted N-aeetylaspartate （NAA） peak, while Cho/NAA increased. Increased glycine （Gly） peakin the 3.55 ppm was found in 4 cases. Conclusion CNC has specific onset age, location and MRI features. MRI has important value for the preoperative diagnosis and differential diagnosis of CNC. DWI and 1H-MRS could show tumor＇s biochemical parameters and tissue metabolism non-invasively from the molecular level, and improve the diagnostic accuracy of CNC.