1H MR spectroscopy characteristics of cerebral alveolar echinococcosis

Abstract

Objective To investigate the characteristics of proton magnetic resonance spectroscopy (1H MRS) in patients with cerebral alveolar echinococcosis (CAE).Methods Thirteen patients with 33 lesions proven to be CAE histologically and clinically were examined by conventional MRI and 2D multivoxel spectroscopy with a 3.0 T double gradient superconductivity magnetic resonance scanner.Concentrations of the metabolites containing N-acetyl-aspartic-acid (NAA),Choline (Cho),Creatine (Cr),lipids and lactic acid (Lip + Lac),myo-Inositol (mI) were detected and the value of Cho/Cr,NAA/Cr,(Lip + Lac)/Cr,mI/Cr were calculated.The values of Cho/Cr,NAA/Cr,(Lip + Lac)/Cr,mI/Cr were compared between the lesions and the contralateral normal brain parenchyma.Statistical analysis was performed using the Wilcoxon signed-rank test.Results CAE 1H MRS in the lesions was characterized by the decrease of Cho,NAA to varying degrees,and a visible lipid with or without lactate peak.Compared with the control group,the ratio of NAA/Cr was decreased markedly,whereas Cho/Cr,mI/Cr increased mildly and (Lip + Lac)/Cr increased markedly in the lesions.The medians and interquartile ranges of Cho/Cr,NAA/Cr,(Lip + Lac)/Cr and mI/Cr in the lesions were:1.88 (1.24-2.23),1.32 (1.07-1.58),32.96 (24.59-47.30) and 0.91 (0.67-1.08),respectively.The medians and interquartile ranges of Cho/Cr,NAA/Cr,(Lip + Lac)/Cr and mI/Cr of control group were 0.84(0.704-0.98),2.00(1.80-2.18),0.90 (0.74-0.99) and 0.26 (0.18-0.31),respectively.There were statistically significant differences of the measures between the lesions and the control regions (Z =-5.932,-6.086,-6.946,-6.984,P ＜0.01).Conclusions Multi-voxel 1H MRS can reflect pathological characteristics of CAE.1 H MRS provides metabolic information for diagnosis of CAE and may be a supplement to conventional magnetic resonance examination. Key words: Echinococcosis ; Magnetic resonance spectroscopy; Brain