Magnetic resonance spectroscopy of ring-enhancing intracerebral lesions
- Author:
Fei KUANG
1
Author Information
1. Department of Radiology
- Publication Type:Journal Article
- From:
Academic Journal of Second Military Medical University
2006;27(9):981-986
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To assess the value of two-dimensional chemical shift imaging magnetic resonance spectroscopy (2D CSI 1H-MRS) in diagnosis of ring-enhancing intracerebral lesions. Methods: Magnetic resonance spectroscopy and magnetic resonance imaging manifestations were analyzed retrospectively in 62 patients with ring-enhancing intracerebral lesions (confirmed by clinical or histopathologic findings), including 20 gliomas, 18 metastatic tumors, 16 brain inflammations, and 8 radiation damages. The appearance rate of lactate (Lac) was analyzed and the concentrations of choline (Cho), N-acetyl aspartate (NAA), creatine (Cr) and NAA/Cho, Cho/Cr and NAA/Cr ratios in the enhancing regions were calculated (including the inside of enhancing regions). Results: (1) There was no difference in appearance rate of Lac among the 4 groups. (2) NAA/Cho ratios in the glioma, metastatic tumor, inflammation and radiation damage group were 0.43±0.32, 0.69±0.29, 1.26±0.53 and 0.63±0.34, respectively, with that of the glioma group being significantly lower than those of the other 3 groups (P<0.05). When NAA/Cho ratio is less than 0.4, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of MRS for high-grade glioma were 80.2%, 77.4%, 71.5% and 89.4%, respectively, all higher than those of MRI, but lower than those of MRI combined with MRS. (3) The concentrations of Cr in glioma, inflammation and radiation damage groups were 0.17±0.05, 0.10±0.05, 0.21±0.08 and 0.21±0.09, respectively, with that of metastatic tumor being significantly lower than those of the other 3 groups (P<0.05). When Cr<0.06, the sensitivity, specificity, PPV and NPV of MRS for metastatic tumor were 81.3%, 81.9%, 74.1% and 90.1%, respectively, all higher than those of MRI, but lower than those of MRI combined with MRS. Conclusion: 2D CSI 1H-MRS is very useful in the differential diagnosis of ring-enhancing intracerebral lesions and the combined application of MRI and MRS has a higher diagnostic value.
