Kinoshita Y, Yokota A
Department of Neurosurgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
NMR Biomed. 1997 Jan;10(1):2-12. doi: 10.1002/(sici)1099-1492(199701)10:1<2::aid-nbm442>3.0.co;2-n.
Water-soluble metabolites extracted from 60 surgically excised samples of various brain tumors and four nontumorous lobectomized brains were measured quantitatively using in vitro high-resolution magnetic resonance spectroscopy. A detailed MR spectrum-histology correlation study in a glioblastoma was made, to reveal MR spectral changes in accordance with the density of glioma cells. Furthermore, three cases that had difficult preoperative diagnoses are discussed. MR spectra from gliomas exhibited characteristic patterns according to malignancy, presumably reflecting its metabolic effects. Concentrations of choline-containing compounds, inositol, alanine, glycine and phosphorylethanolamine (PEA) increased according to the degree of malignancy, but it was noteworthy that in glioblastoma the choline-containing compounds, inositol, alanine, glycine and phosphorylethanolamine increased according to the degree of malignancy. In particular, the glycine concentration was very high in glioblastoma. We also detected a large amount of taurine in medulloblastoma. Although the total creatine concentrations decreased according to the malignancy, the concentration of total creatine was relatively preserved in neuroectodermal tumors but was low in nonneuroectodermal tumors. N-acetyl-aspartate was unequivocally demonstrated in normal tissues, but could not be detected in nonneuroectodermal brain tumors such as metastatic brain tumor, meningioma, neurinoma and chordoma. In meningioma, although a high peak of choline-containing compounds has been reported uniquely by in vitro and in vivo 1H-MRS, we demonstrated that its concentration was not increased in meningioma; instead, there was an increased alanine content. 1H-MRS of neurinoma demonstrated high inositol peaks, and a large amount of inositol. The reason for the high inositol content in neurinoma is unknown, but the prominent peak of inositol on MR spectra should be useful for the differential diagnosis of neurinoma from meningioma. PEA concentration was increased four to five times in pituitary adenoma, malignant lymphoma, and medulloblastoma as compared with normal brain. Thus 1H-MRS might provide clinically useful information on tumor malignancy and characteristic tumor metabolism. Although excellent anatomical information of tumors can be readily obtained by magnetic resonance imaging. MRS provides metabolic information. MRS may provide additional information in cases in which the differential diagnosis of tumors by neuroimaging is difficult.
采用体外高分辨率磁共振波谱法对从60例手术切除的各种脑肿瘤样本和4例非肿瘤性脑叶切除脑组织中提取的水溶性代谢物进行了定量测定。对1例胶质母细胞瘤进行了详细的磁共振波谱-组织学相关性研究，以揭示与胶质瘤细胞密度相关的磁共振波谱变化。此外，还讨论了3例术前诊断困难的病例。胶质瘤的磁共振波谱根据恶性程度呈现出特征性模式，可能反映了其代谢效应。含胆碱化合物、肌醇、丙氨酸、甘氨酸和磷酸乙醇胺（PEA）的浓度随恶性程度增加而升高，但值得注意的是，在胶质母细胞瘤中，含胆碱化合物、肌醇、丙氨酸、甘氨酸和磷酸乙醇胺随恶性程度增加而升高。特别是，胶质母细胞瘤中的甘氨酸浓度非常高。我们还在髓母细胞瘤中检测到大量牛磺酸。虽然总肌酸浓度随恶性程度降低，但总肌酸浓度在神经外胚层肿瘤中相对保持不变，而在非神经外胚层肿瘤中较低。N-乙酰天门冬氨酸在正常组织中明确显示，但在非神经外胚层脑肿瘤如脑转移瘤、脑膜瘤、神经鞘瘤和脊索瘤中无法检测到。在脑膜瘤中，虽然体外和体内1H-MRS均独特地报道了含胆碱化合物的高峰，但我们证明其在脑膜瘤中的浓度并未升高；相反，丙氨酸含量增加。神经鞘瘤的1H-MRS显示出高肌醇峰和大量肌醇。神经鞘瘤中肌醇含量高的原因尚不清楚，但磁共振波谱上明显的肌醇峰应有助于神经鞘瘤与脑膜瘤的鉴别诊断。与正常脑相比，垂体腺瘤、恶性淋巴瘤和髓母细胞瘤中的PEA浓度增加了4至5倍。因此，1H-MRS可能为肿瘤恶性程度和特征性肿瘤代谢提供临床有用信息。虽然通过磁共振成像可以很容易地获得肿瘤的优秀解剖信息，但磁共振波谱提供代谢信息。在神经影像学对肿瘤进行鉴别诊断困难的情况下，磁共振波谱可能提供额外信息。
