1HMRS在鉴别脑内单发环形强化病变中的应用

目的：分析3.0T氢质子磁共振波谱成像（1HMRS）在鉴别脑内单发环形强化病变中的应用。方法应用PHILIPS 3.0T磁共振扫描仪对65例在MRI增强扫描时表现为脑内单发环形强化病变的患者治疗前行1HMRS扫描，经病理证实或临床确诊为30例高级别胶质瘤、23例单发脑转移瘤和12例脑脓肿。分别测量病灶中心及周围水肿区的NAA、Cho及Cr峰的峰下面积，计算NAA/Cr、Cho/Cr、NAA/Cho比值，并记录病灶中心Lac和Lip峰是否出现。对各参数值进行统计学分析，明确其对鉴别三种疾病的诊断价值。结果病灶中心的Cho值胶质瘤﹥转移瘤﹥脑脓肿；Cho/Cr值胶质瘤﹥脑脓肿（P﹤0.05）；NAA/Cho值脑脓肿﹥转移瘤﹥高级别胶质瘤；NAA及NAA/Cr在三组之间差异均无统计学意义。周围水肿区的NAA/Cr转移瘤组﹥脑脓肿组；Cho/Cr比值差异有显著统计学意义（P﹤0.001），胶质瘤组﹥脑脓肿组﹥转移瘤组，高级别胶质瘤组明显高于单发脑转移瘤组（P=0.000）且Cho/Cr临界值为1.5650时诊断为高级别胶质瘤的敏感度为73.3%，特异度为94.4%，ROC曲线下面积为0.921。周围水肿区NAA/Cho差异有显著统计学意义（P﹤0.001），转移瘤组高于胶质瘤组和脑脓肿组。高级别胶质瘤Lip峰出现率低于转移瘤和脑脓肿，转移瘤和脑脓肿组间比较差异无统计学意义。结论1HMRS可用于鉴别脑内单发环形强化病变，病灶中心的NAA/Cho和周围水肿区的Cho/Cr比值对高级别胶质瘤、单发脑转移瘤和脑脓肿的鉴别诊断具有重要意义。

Application of 1HMRS in differentiating intracranial solitary lesions with ring-like enhancement

Objective To analyze whether 1H-magnetic resonance spectroscopy (1HMRS) can be used to differentiate intracranial solitary lesions with ring-like enhancement. Method 65 patients with intracranial solitary lesions with ring-like enhancement observed in contrast enhancement MRI underwent 1H-MRS examination using a Philips 3.0T scanner before treatment, in which there were 30 cases of high grade glioma, 23 patients with single brain metastases and 12 cases of brain abscess were confirmed pathologically or clinically. NAA, Cho and Cr in the lesion core and peripheral edema ar-ea of all patients were evaluated with accessory software, NAA/Cr, Cho/Cr and NAA/Cho ratios were calculated, and the number of Lac as well as Lip peak appearing from the core of lesion was recorded. Various parameters were included in the statistical analysis to evaluate the diagnostic value. Result The Cho value in the lesion core of glioma was higher than brain abscess, and was higher in brain metastasis than brain abscess;The Cho/Cr value of glioma was higher than brain abscess (P<0.05);The brain abscess group had a higher NAA/Cho value than brain metastasis group, followed by the high-grade glioma group (P<0.05);There were no statistically significant differences of NAA and NAA/Cr among the three groups;The NAA/Cr value in the peripheral edema area of metastasis group was higher than brain abscess group;The Cho/Cr value was significantly different among the three groups (P<0.001), with highest level in glioma group, fol-lowed by brain abscess group, and then metastasis group, with a significant higher value observed in the high-grade glio-ma than solitary metastasis group (P=0.000), and when the cut-off value of Cho/Cr was 1.5650, the sensitivity for a diag-nosis of glioma was 73.3%, with a specificity of 94.4%. The area under the ROC curve was 0.921. The NAA/Cho values in the peripheral edema of the metastasis group was higher than glioma group and brain abscess group (P<0.001). The oc-currence rate of the peak of Lac and Lip in the glioma group was less than other groups, while there were no statistical dif-ferences regarding the Lip concentration between metastasis group and brain abscess group. Conclusion 1HMRS can be used to distinguish intracranial solitary lesions with ring-like enhancement. The NAA/Cho value in the lesion core and the Cho/Cr value in the peripheral edema area are significant indicators for differential diagnosis among high-grade glioma, solitary metastasis and brain abscess.