1 H MR Spectroscopy in Patients with Metastatic Brain Tumors: A Multicenter Study

In a cooperative study involving six clinical MR centers, localized 1 H MR spectroscopy was used to characterize untreated metastatic brain tumors (40 cases, 45 lesions). Cubic volumes (3.4 or 8 cm 3 ) filled for more than 50% by metastatic brain tissue were examined by single‐voxel double spin echo MRS, by using chemical shift selective imaging (CHESS) pulses for water suppression and TE = 135 ms. Choline (Cho), creatine (Cr) and N ‐acetyl aspartate (NAA) levels in brain metastases of mammary carcinoma ( n = 13), lung cancer ( n = 11) and melanoma ( n = 10) were similar. Metastasis NAA/Cho signal intensity ratio varied between 0.00 and 1.17, compared with 2.68 ± 0.56 (SD) in lobus occipitalis and 1.94 ± 0.63 in corpus nuclei caudati region ( P < 0.0001, both). 1 H MR spectroscopy, although not suited to recognize the primary tumor of metastases, could serve as a clinical test for excluding (metastatic) tumor as cause of solitary focal brain disorders that are hard to diagnose with current imaging methods.