摘要
目的利用多体素质子谱成像,对颅内胶质瘤患者在手术前对其浸润边界及病理学级别进行分析,并提出新的评价方法,探讨MR多体素质子谱成像在胶质瘤中的应用价值. 方法经手术及病理证实的胶质瘤共30例.行常规MR检查及增强检查,随后行多体素质子谱扫描.采用胆碱(Cho)/N-乙酰天冬氨酸(NAA)残差z分数统计模型确定肿瘤的边界,最大z分数所在区域确定肿瘤的高代谢活性区,采用最大z分数、肿瘤最高乳酸指标(LLI)值及有无乳酸盐(Lac)/Cho>1的体素出现等3项指标确定肿瘤的级别. 结果传统的MR扫描显示出肿瘤的瘤体及周围水肿影,15例在增强扫描中表现不同的强化影;用多体素质子谱定量分析方法所确定的肿瘤边界均超过常规MRI所确定的肿瘤边界,且可见其边界呈浸润性生长.在20例2～3级肿瘤中,其肿瘤内高的代谢活性区在常规MRI所确定的肿瘤区内;而在10例4级肿瘤中,有8例其肿瘤内高代谢活性区在常规MRI所确定的肿瘤区外.2级胶质瘤的最大z分数为6.40±2.43,3级为16.83±7.28,4级为9.16±4.38.3级的最大z分数均高于2级和4级,4级高于2级,差异具有统计学意义(t34=-2.61,P=0.01;t32=3.91,P=0.002;t42=1.90,P=0.04).2级胶质瘤的最大LLI值为9.24±5.33, 3级为22.27±14.63, 4级为38.41±11.45.LLI值随肿瘤级别的升高而增大,差异具有统计学意义(t34=2.56,P=0.01;t32=2.41,P=0.02;t42=7.42,P<0.01).4级胶质瘤有Lac/Cho>1的区域出现,即出现显著性坏死,而2、3级肿瘤均无Lac/Cho>1的区域出现.结论 MR多体素质子谱成像可提供肿瘤代谢方面的功能信息,可评价胶质瘤对正常脑组织的浸润及其恶性度,结合常规MR结构成像,可为术前准确、全面评价胶质瘤、制定个性化的治疗方案提供有价值的参考信息.
Objective To evaluate multivoxel magnetic resonance spectroscopy imaging （MRSI） in the diagnosis of glioma. Methods Conventional MRI and contrast enhanced MRI were performed in 30 patients with histologically verified glioma, then multivoxel-MRSI were applied in these patients. The Cho/NAA residual z-score model was applied to define the tumor margin, and the maximal value of z-score was used to determine the high activity region of glioma. Three indicators, including maximal value of z- score, maximal value of LLI, and the appearance of the voxels with the ratio of Lac/Cho greater than 1, were employed to determine histological grade of glioma. Results Conventional MRI demonstrated solid mass and edema in 30 patients, and different extent of contrast enhancement were observed in 15 patients. In 20 gliomas of grade 2 and grade 3, the high active region defined by MRSI was inside the region of contrast enhancement; but in 8 of 10 grade 4 gliomas, the high active region defined by MRSI was outside the region of contrast enhancement. The maximal value of z-score of grade 2 was 6.40 ± 2.43, grade 3 was 16. 83 ± 7.28, and grade 4 was 9.16 ±4. 38. The maximal value of z-score of grade 3 was higher than that of grade 2 and grade 4, and grade 4 was higher than grade 2, the significant difference was found （t34 = - 2. 61, P = 0.01; t32 =3.91, P=0.002; t42 = 1.90, P =0.04）. The maximal value of LLI of grade 2 was 9.24 ± 5. 33, grade 3 was 22. 27 ± 14. 63, and grade 4 was 38.41 ± 11.45. The maximal value of LLI increased with grades, and the significant difference was found in each grade （t34 =2. 56, P =0. 01; t32 =2. 41, P = 0. 02; t42 =7. 42, P 〈0. 01 ）. Necrosis was found in grade 4 but not in grade 2 and grade 3, that was the appearance of the voxels with the ratio of Lac/Cho greater than 1, which could be detected in grade 4, but not in grade 3 and grade 2. Condusion The MRSI could provide functional information about metabolism of glioma, and could evaluate tumor malignancy and its infiltration. It
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2005年第11期1192-1197,共6页
Chinese Journal of Radiology
基金
国家自然科学基金(10275003
10175004)
北京市自然科学基金(3011002)
