Hugg J W, Matson G B, Twieg D B, Maudsley A A, Sappey-Marinier D, Weiner M W
MR Unit, Department of Veterans Affairs Medical Center, San Francisco, CA.
Magn Reson Imaging. 1992;10(2):227-43. doi: 10.1016/0730-725x(92)90483-g.
The goals of this study were to evaluate 31P MR spectroscopic imaging (MRSI) for clinical studies and to survey potentially significant spatial variations of 31P metabolite signals in normal and pathological human brains. In normal brains, chemical shifts and metabolite ratios corrected for saturation were similar to previous studies using single-volume localization techniques (n = 10; pH = 7.01 +/- 0.02; PCr/Pi = 2.0 +/- 0.4; PCr/ATP = 1.4 +/- 0.2; ATP/Pi = 1.6 +/- 0.2; PCr/PDE = 0.52 +/- 0.06; PCr/PME = 1.3 +/- 0.2; [Mg2+]free = 0.26 +/- 0.02 mM.) In 17 pathological case studies, ratios of 31P metabolite signals between the pathological regions and normal-appearing (usually homologous contralateral) regions were obtained. First, in subacute and chronic infarctions (n = 9) decreased Pi (65 +/- 12%), PCr (38 +/- 6%), ATP (55 +/- 6%), PDE (47 +/- 9%), and total 31P metabolite signals (50 +/- 8%) were observed. Second, regions of decreased total 31P metabolite signals were observed in normal pressure hydrocephalus (NPH, n = 2), glioblastoma (n = 2), temporal lobe epilepsy (n = 2), and transient ischemic attacks (TIAs, n = 2). Third, alkalosis was detected in the NPH periventricular tissue, glioblastoma, epilepsy ipsilateral ictal foci, and chronic infarction regions; acidosis was detected in subacute infarction regions. Fourth, in TIAs with no MRI-detected infarction, regions consistent with transient neurological deficits were detected with decreased Pi, ATP, and total 31P metabolite signals. These results demonstrate an advantage of 31P MRSI over single-volume 31P MRS techniques in that metabolite information is derived simultaneously from multiple regions of brain, including those outside the primary pathological region of interest. These preliminary findings also suggest that abnormal metabolite distributions may be detected in regions that appear normal on MR images.
本研究的目的是评估用于临床研究的31P磁共振波谱成像（MRSI），并调查正常和病理性人脑31P代谢物信号潜在的显著空间变化。在正常大脑中，经饱和校正后的化学位移和代谢物比率与先前使用单体积定位技术的研究结果相似（n = 10；pH = 7.01±0.02；PCr/Pi = 2.0±0.4；PCr/ATP = 1.4±0.2；ATP/Pi = 1.6±0.2；PCr/PDE = 0.52±0.06；PCr/PME = 1.3±0.2；[Mg2+]游离 = 0.26±0.02 mM）。在17例病理病例研究中，获得了病理区域与外观正常（通常为同源对侧）区域之间的31P代谢物信号比率。首先，在亚急性和慢性梗死（n = 9）中，观察到无机磷（Pi）降低（65±12%）、磷酸肌酸（PCr）降低（38±6%）、三磷酸腺苷（ATP）降低（55±6%）、磷酸二酯（PDE）降低（47±9%）以及总31P代谢物信号降低（50±8%）。其次，在正常压力脑积水（NPH，n = 2）、胶质母细胞瘤（n = 2）、颞叶癫痫（n = 2）和短暂性脑缺血发作（TIA，n = 2）中观察到总31P代谢物信号降低的区域。第三，在NPH脑室周围组织、胶质母细胞瘤、癫痫同侧发作灶和慢性梗死区域检测到碱中毒；在亚急性梗死区域检测到酸中毒。第四，在未检测到MRI梗死的TIA中，在与短暂性神经功能缺损一致的区域检测到Pi、ATP和总31P代谢物信号降低。这些结果表明31P MRSI相对于单体积31P MRS技术的优势在于，代谢物信息可同时从大脑的多个区域获取，包括主要感兴趣病理区域之外的区域。这些初步发现还表明，在MR图像上看似正常的区域可能检测到异常的代谢物分布。
