最小表观弥散系数对颅内少突胶质肿瘤分级及分型的价值

目的:评价最小表观弥散系数对颅内少突胶质肿瘤分级及分型的价值.材料和方法:24个病理证实为少突胶质肿瘤的病人(男性13人,女性11人,平均年龄45岁),包括4个Ⅲ级(间变型)少突星形细胞瘤(oligoastrocytomas,OA),6个Ⅲ级(间变型)少突胶质瘤(oligodendrogliomas,OD),2个Ⅱ级少突星形细胞瘤和12个Ⅱ级少突胶质瘤共4组.在肿瘤实质部分测定最小表观弥散系数(minimum apparent diffusion coefficient,AD Cmin)值及对侧正常脑白质的ADC值,并计算其相对值(relative ADCmin).比较不同分级及病理分型组间平均rADCmin值并统计分析.结果:不同分型少突胶质肿瘤平均rADCmin分别为Ⅲ级OA0.95±0.05,Ⅲ级OD1.11±0.30,Ⅱ级OA1.69±0.59,Ⅱ级OD1.45±0.41,与肿瘤分级及恶性程度呈负相关(P=0.004).rADCmin在两种级别少突胶质肿瘤中有显著性差异(P=0.014), 进一步两两比较显示rADCmin在Ⅲ级OA与Ⅱ级OD,Ⅱ级OA之间均有显著性差异(P=0.027,P=0.029).但Ⅲ级OD与Ⅱ级OD,Ⅱ级OA其平均rADCmin无显著性差异(P=0.067～0.081);当分界值rADCmin=1.03时鉴别Ⅱ级少突胶质肿瘤与Ⅲ级OA的敏感度为100%,特异度100%,但鉴别两种级别的少突胶质肿瘤敏感度仅60%,特异度100%.结论:rADCmin可以为少突胶质肿瘤分级提供有价值的信息,选择最适分界值rADCmin=1.03,可以鉴别Ⅲ级少突星形细胞瘤和Ⅱ级少突胶质肿瘤;但由于Ⅲ级OD其rADCmin与其余各组的交叉重叠,单独应用rADCmin鉴别两种级别肿瘤价值有限,rADCmin小于1.03可排除Ⅱ级少突胶质肿瘤.     

胶质瘤的弥散图像与微观病理状态的关系的研究

目的　探讨胶质瘤表观弥散系数 (ADC)与病理微观状态的关系。资料与方法　 2 7例胶质瘤分为低级别、渐变型和胶质母细胞瘤 3组 ,测量肿瘤固体部分的ADC值 ,分析不同级别胶质瘤的ADC值的差异性。其中 11例行病理分析 ,比较与细胞构成和核质比的相关性。结果　低级别胶质瘤 (1.80± 0 .33)相对ADC值较渐变型(1.5 3± 0 .2 2 )和胶质母细胞瘤 (1.19± 0 .2 3)高。绝对ADC与细胞构成 (r=- 0 .70 ,P <0 .0 1)和核质比 (r =- 0 .77,P <0 .0 1)成负相关 ,与核质比的相关性较细胞构成高。结论　弥散图像中胶质瘤的ADC可预测肿瘤的级别 ,并可反映胶质瘤的病理状态 ,提供常规MRI所没有的参数 ,提高了对胶质瘤的诊断水准     

对术中超声在神经胶质瘤分级中的诊断价值的探讨

通过分析不同等级胶质瘤的超声声像图表现,探讨术中超声在胶质增生和胶质瘤鉴别诊断以及胶质瘤分级中的临床应用价值.材料和方法:对21例胶质增生及胶质瘤患者的术中超声声像图进行回顾性分析,比较胶质增生及不同等级胶质瘤的超声声像图特征.结果:2例胶质增生,6例低级别胶质瘤,4例间变性胶质瘤和9例胶质母细胞瘤的声像图各具特征.尤其是高级别胶质瘤内的坏死液化发生率达到了53.8%(7/13),而胶质增生和低级别胶质瘤中均未见坏死液化灶,两者差异存在显著性(P＜0.05).结论:术中超声在诊断胶质增生及对胶质瘤分级中具有一定的应用价值.     

超声在神经胶质瘤术中的应用价值

目的:通过分析胶质增生和不同级别胶质瘤的超声声像图表现,探讨术中超声在胶质增生及胶质瘤鉴别诊断和分级中的应用价值。方法:对11例胶质增生和104例胶质瘤患者的术中超声声像图进行回顾性分析,比较胶质增生和不同级别胶质瘤的超声声像图特征。结果:胶质增生和各级别胶质瘤的声像图各具特征。各组间病灶的形态、边界和钙化差异无统计学意义,而内部回声、有无囊变和病灶周边脑组织水肿厚度各组间差异有统计学意义(P<0.05)。结论:术中超声在诊断胶质增生和胶质瘤分级中具有一定的应用价值。     

表观弥散系数的直方图特征与弥漫性胶质瘤组织学分级、Ki⁃67增殖指数的对照研究北大核心CSCD

目的:探讨表观弥散系数(ADC)的直方图特征鉴别弥漫性胶质瘤高、低级别的价值,并评价其与Ki-67增殖指数的相关性。方法:回顾性分析67例经术后病理证实的弥漫性胶质瘤(其中高级别组48例,低级别组19例)的影像学及病理学资料。比较高、低级别组弥漫性胶质瘤ADC值的多个直方图特征差异,对满足正态分布及方差齐性的特征采用独立样本t检验进行分析,对不满足正态分布或方差不齐的特征采用Mann⁃Whitney秩和检验,然后绘制ROC曲线以评价其ADC值直方图特征鉴别高、低级别脑胶质瘤的效能。采用Pearson相关分析评价ADC值的直方图特征与Ki⁃67增殖指数的相关性。结果:高级别胶质瘤的ADC最大值、标准差及不均匀度分别为2.395(2.359,3.227)×10^(-3)mm^(2)/s、0.410(0.306,0.534)×10^(-3)mm^(2)/s、0.305±0.086,大于低级别胶质瘤相对应的直方图特征[分别为2.107(1.927,2.546)×10^(-3)mm^(2)/s、0.204(0.171,0.383)×10^(-3)mm^(2)/s、0.203±0.114],2组间差异具有统计学意义(P值分别为0.025、0.001、0.000)。高级别胶质瘤的ADC值第10百分位数、第25百分位数分别为0.825(0.749,0.991)×10^(-3)mm^(2)/s、(1.068±0.246)×10^(-3)mm^(2)/s,小于低级别胶质瘤相对应的直方图特征[分别为1.191(0.863,1.313)×10^(-3)mm^(2)/s、(1.225±0.297)×10^(-3)mm^(2)/s],2组间差异具有统计学意义(P值分别为0.002、0.029)。ROC曲线示ADC值的不均匀度鉴别高、低级别胶质瘤的ROC曲线下面积最大(0.815),同时对鉴别诊断的灵敏度最高(95.8%),最大值、第10百分位数的特异度最高(均为68.4%)。Pearson相关性分析示ADC值的第10百分位数与Ki⁃67增殖指数呈负相关(r=-0.415,P=0.002),不均匀度与Ki⁃67增殖指数呈正相关(r=0.343,P=0.008)。结论:表观弥散系数的直方图特征有助于预测弥漫性胶质瘤的组织学分级、Ki⁃67增殖指数,对胶质瘤临床治疗方案的选取具有一定的价值。     

多b值DWI对术前幕上胶质瘤分级的应用研究

目的：探讨何种 b 值扩散加权成像(DWI)对胶质瘤术前分级更有价值。方法回顾性分析经手术病理证实的38例胶质瘤(高级别24例、低级别14例)患者的 MRI 资料,均行常规 MRI 检查和3种 b 值的 DWI 检查(b=1000 s/mm2、2000 s/mm2、3000 s/mm2),分析 DWI 上肿瘤的信号特征,测量肿瘤最小表观扩散系数(ADC)值。对不同 b 值的肿瘤最小 ADC 值绘制受试者工作特征曲线(ROC),选取最佳诊断阈值,采用χ2检验分析不同序列的敏感性、特异性的差异。结果 b= 3000 s/mm2 DWI 图像上,91.6%(22/24)高级别胶质瘤呈高信号,85.7%(12/14)低级别胶质瘤呈低信号,以高信号作为诊断高级别胶质瘤的标准,诊断高级别和低级别胶质瘤的敏感性及特异性最高(91.6%和100%)。在 b 值相同时高级别胶质瘤的最小 ADC 值低于低级别胶质瘤,差异有统计学意义(P<0.05);3种 b 值鉴别高级别和低级别胶质瘤敏感性的差异有统计学意义(P<0.05),当以 ADC 3000<0.74×10-3 mm2/s 作为鉴别高级别胶质瘤的敏感性和特异性最高,分别为100%和87.3%。结论高 b 值 DWI 比常规 b 值 DWI 更能准确反映胶质瘤分级,应用 b=3000 s/mm2 DWI 肿瘤最小 ADC 值为胶质瘤术前更准确分级提供量化指标。     

MR弥散加权成像在子宫内膜良恶性病变中的鉴别价值

目的 探讨MR弥散加权成像(DWI)及其表观弥散系数(ADC)在子宫内膜良恶性病变中的鉴别价值.方法 回顾性分析55例经病理证实的子宫内膜病变,其中良性组14例(6例内膜增生、8例内膜息肉),恶性组41例(39例内膜癌、2例癌肉瘤).所有病例行常规MRI平扫和增强检查,以及DWI(弥散敏感因子b值为0、1000s/mm2),分析病变的DWI信号特点和测定ADC值.结果 良性组DWI图12例表现为稍高信号、2例表现为等信号、平均ADC值为(1.34±0.19)×103mm2/s;恶性组DWI图34例表现为明显高信号,余下7例表现为稍高信号,平均ADC值为(0.84±0.14)×103 mm2/s;恶性组ADC值明显小于良性组(P=0.042),以1.07×103 mm2/s为临界值诊断子宫内膜良恶性病变的敏感性、特异性、准确性高达92.9％、97.6％、96.4％.结论 DWI及ADC值测定有助于子宫内膜良恶性病变的鉴别诊断.     

弥散张量成像相对各向异性值和相对表观系数值在评价脑胶质瘤级别中的研究

目的 探讨弥散张量成像(DTI)相对各向异性(rFA)值和相对表观系数(rADC)值在评价脑胶质瘤病理等级中的应用价值.方法 对27 例经手术及组织病理学证实的胶质瘤患者,术前行常规MRI、DTI 检查.在FA 图上,感兴趣区分别设定在瘤体实质部(FA1)、瘤体边缘(FA2),周围水肿(FA3),以及对侧半球皮质脊髓束(FAc),测量出FA1、FA2、FA3及FAc 值;在相同层面ADC 图上同位置,测量出ADC1、ADC2 、ADC3及ADCc 值,计算出相对FA值(rFA1-3)和相对ADC 值(rADC1-3), rFA、rADC 与胶质瘤的病理级别之间关系进行统计学处理.结果 27例胶质瘤患者,其中低级别胶质瘤(WHO grade I～ II )14 例,高级别胶质瘤(WHO grade III～IV)13例.肿瘤实质部rFA1值与肿瘤级别无显著相关性(r＝0.328,P＞0.05),肿瘤边缘的rFA2值高级别胶质瘤高于低级别(t=2.453,P＜0.05),水肿区高级别胶质瘤的rFA3值低于低级别(t=2.318, P＜0.05);肿瘤实质部rADC1值、肿瘤边缘rADC2值与肿瘤恶性程度存在显著负相关(r分别为-0.393、-0.404, P值均＜0.05),水肿区高级别胶质瘤的rADC3值高于低级别(t=4.715, P＜0.01).结论 胶质瘤边缘的rFA2值、水肿区rFA3值及胶质瘤瘤体部、边缘、水肿区的rADC值在胶质瘤的术前病理分级诊断中具有参考价值.     

MinADC值评价低级别胶质瘤生物学行为的诊断价值

目的探讨磁共振(MRI)最小表观弥散系数(min ADC)值在评价低级别胶质瘤生物学行为及预后的应用价值。方法选取21例低级别胶质瘤患者,根据欧洲肿瘤研治中心标准,将其分为低危组和高危组,在治疗前行常规MRI、弥散加权成像(DWI)及增强扫描,在工作站上测量肿瘤实质区的ADC值,选取最小值作为min ADC值,用独立样本t检验分析两组之间min ADC值的差异性。结果低危组和高危组肿瘤实质区平均min ADC值分别为:(1.11±0.31)×10^(-3)mm^2/s和(0.72±0.19)×10^(-3)mm^2/s,低危组的min ADC值高于高危组,并且差异具有统计学意义。结论胶质瘤肿瘤实质区min ADC值对评价低级别胶质瘤的生物学行为及预后具有重要的临床价值。     

磁敏感加权成像在胶质瘤分级中的应用价值初探

初步探讨磁敏感加权成像(SWI)在胶质瘤分级中的应用价值。收集经手术病理证实的高级别胶质瘤13例和低级别胶质瘤11例,均做了MRI平扫、增强扫描和SWI,按照WHO中枢神经系统肿瘤分类标准对肿瘤分级,由两位神经放射诊断医师对SWI肿瘤内的低信号进行评分,分析测定两组肿瘤的SWI低信号评分有无统计学差异。11例高级别组肿瘤实质出现明显低信号(敏感性84.6%),7例低级别组肿瘤内出现明显低信号(特异性36.4%),高级别组肿瘤低信号评分值高于低级别组(P<0.05)。磁敏感加权成像有助于胶质瘤的分级。     

慢性脑内血肿的影像误诊分析与鉴别诊断

目的:探讨慢性脑内血肿CT、MRI的误诊原因及鉴别诊断依据。方法:回顾性分析临床及手术证实的21例慢性脑内血肿的影像资料,其中21例CT平扫及增强,8例同时行MRI检查。结果:术前5例诊断为囊性胶质瘤,4例转移瘤,1例脑脓肿,此10例开颅手术证实为脑内血肿,并伴反应性胶质增生;另11例临床动态观察吸收后证实。结论:慢性脑内血肿具有占位效应轻、均匀环形强化及MRI图像上有均匀铁环的影像特点,详细询问病史及治疗后动态观察可以减少误诊。     

Evaluation of 99mTc-L-methionine brain SPECT for detection of recurrent brain tumor: a pilot study with radiological and pathological correlation

PURPOSE: To evaluate technetium labeled L-methionine for imaging recurrent brain tumors. MATERIAL AND METHODS: Brain SPECT with 99mTc-L-methionine was performed to evaluate tumor viability in 42 patients with primary brain tumor. Findings of SPECT were correlated with radiological and histopathological findings as reference. RESULTS: 99mTc-L-methionine showed localized increased uptake in 40 patients with tumor recurrence, whereas 2 patients with post-radiation gliosis did not show tracer accumulation. A low differential uptake rate (DUR) 2.43 +/- 0.74 and methionine retention (MR) index 0.93 +/- 0.03 was seen in cases of post-radiation gliosis. A high DUR (36.20 +/- 10.31) and MR index (4.87 +/- 2.37) was seen in cases of recurrent tumor. Mean DUR in high-grade tumors (44.01 +/- 8.46) was significantly higher (P<0.001) than in low-grade tumors (30.42 +/- 7.38), and mean MR index in high-grade tumors (7.03 +/- 2.05) was significantly higher than in low-grade tumors (3.27 +/- 0.82) (P<0.001). CONCLUSION: 99mTc-L-methionine can be used as a SPECT tracer to differentiate tumor recurrence from post-radiation gliosis.     

DTI对鉴别脑低级别胶质瘤、脑梗死和病毒性脑炎的价值

目的:探讨磁共振扩散张量成像在鉴别低级别脑胶质瘤、脑梗死和病毒性脑炎中的应用价值。方法:22例低级别脑胶质瘤、26例急性或亚急性期脑梗死和18例病毒性脑炎患者在治疗或手术前行常规MRI和DTI检查。脑低级别胶质瘤患者均经手术病理证实,病毒性脑炎和脑梗死患者均经临床治疗及随访证实。测量并计算3组病灶的表观扩散系数(ADC)值和相对表观扩散系数(rADC)值、各向异性分数(FA)值和相对各向异性分数(rFA)值,并进行统计学分析。结果:脑低级别胶质瘤组平均ADC、rADC、FA和rFA值分别为(1.55±0.08)×10-3 mm2/s、1.68±0.25、0.17±0.03和0.42±0.08,脑梗死组分别为(0.54±0.12)×10-3 mm2/s、0.64±0.12、0.14±0.03和0.30±0.05,病毒性脑炎组分别为(0.84±0.07)×10-3 mm2/s、1.07±0.05、0.17±0.02和0.43±0.09。三组病例的平均ADC值及rADC值间的差异有高度统计学意义(P<0.01),脑低级别胶质瘤与脑梗死的FA值和rFA值之间、病毒性脑炎与脑梗死的FA值和rFA值之间差异有高度统计学意义(P<0.01),脑低级别胶质瘤与病毒性脑炎的FA值和rFA值之间差异无统计学意义(P>0.05)。结论:综合利用DTI的ADC值、rADC值、FA值及rFA值,对鉴别脑低级别胶质瘤、脑梗死和病毒性脑炎具有较高的指导价值。     

Prognostic value of O-(2-18F-fluoroethyl)-L-tyrosine PET and MRI in low-grade glioma.

In glioma of World Health Organization (WHO) grade II (low-grade glioma), the natural course of a particular patient is not predictable and the treatment strategy is controversial. We determined prognostic factors in adult patients with untreated, nonenhancing, supratentorial low-grade glioma with special regard to PET using the amino acid O-(2-(18)F-fluoroethyl)-L-tyrosine ((18)F-FET) and MRI. METHODS: In a prospective study, baseline (18)F-FET PET and MRI analyses were performed on 33 consecutive patients with histologically confirmed low-grade glioma. None of the patients had radiation or chemotherapy. Clinical, histologic, therapeutic (initial cytoreduction vs. biopsy), (18)F-FET uptake, and MRI morphologic parameters were analyzed for their prognostic significance. Statistical endpoints were clinical or radiologic tumor progression, malignant transformation to glioma of WHO grade III or IV (high-grade glioma), and death. RESULTS: Baseline (18)F-FET uptake and a diffuse versus circumscribed tumor pattern on MRI were highly significant predictors of prognosis (P < 0.01). By the combination of these prognostically significant variables, 3 major prognostic subgroups of low-grade glioma patients could be identified. The first of these subgroups was patients with circumscribed low-grade glioma on MRI without (18)F-FET uptake (n = 11 patients, progression in 18%, no malignant transformation and no death). The second subgroup was patients with circumscribed low-grade glioma with (18)F-FET uptake (n = 13 patients, progression in 46%, malignant transformation to a high-grade glioma in 15%, and death in 8%). The third subgroup was patients with diffuse low-grade glioma with (18)F-FET uptake (n = 9 patients, progression in 100%, malignant transformation to a high-grade glioma in 78%, and death in 56%). CONCLUSION: We conclude that baseline amino acid uptake on (18)F-FET PET and a diffuse versus circumscribed tumor pattern on MRI are strong predictors for the outcome of patients with low-grade glioma.     

Imaging evidence of early brain tissue degeneration in patients with vanishing white matter disease: a multimodal MR study

To find imaging signs of active degenerative processes in vanishing white matter disease (VWM), six VWM patients and six matched controls underwent MR examinations. The data were analyzed with modified Scheltens scales for morphological findings and determined quantitatively for apparent diffusion coefficient (ADC). Single-voxel MR spectra were acquired at the parietal white matter and analyzed with LCModel. Typical VWM brain lesions were found in all patients accompanied by proton diffusion abnormalities: Increased ADC appeared in brain regions with severe myelin destruction in all patients, and reduced ADC in two of six younger patients in remaining white matter adjacent to the lesions or at the borders around the lesions, who had a short history of the disease (≤ 1 year). The MR spectroscopy revealed reductions of NAA, Cho, and Cr, which correlate to the grade of white matter abnormalities. An increase of myo-inositol as marker of reactive gliosis was missing. Thus, restricted proton diffusion was evident in younger VWM patients with short history of disease, which in combination with lack of reactive gliosis may reflect early white matter degeneration in VWM. The multimodal MR methods are useful for characterizing such tissue degeneration in brain in vivo.     

Gross-total surgery of supratentorial low-grade gliomas under intraoperative MR guidance

BACKGROUND AND PURPOSE: Length of survival of patients with low-grade glioma correlates with the extent of tumor resection. These tumors, however, are difficult to distinguish intraoperatively from normal brain tissue, often leading to incomplete resection. Our goal was to evaluate the effectiveness of intraoperative MR guidance in achieving gross-total resection. METHODS: We studied 12 patients with low-grade glioma who underwent surgery within a vertically open 0.5-T MR system. During surgery, localization of residual tumor tissue was guided by interactive, near real-time imaging. The amount of residual tumor tissue on MR images was evaluated at the point of the operation at which the neurosurgeon would have terminated the procedure under conventional conditions (first control) and again before closing the craniotomy. RESULTS: Significant residual tumor (more than 10% of original tumor volume) was shown in eight patients at the first control condition. The percentage of resection varied from 26% to 100% (mean, 68%) at this time. Twelve tissue samples from seven patients were obtained in areas identified as residual tumor on MR images. In 10 cases, the neuropathologic investigation confirmed the presence of residual low-grade glioma; in two cases, the borderzone of tumor was identified. In evaluating the final sets of images, we found total resection in six cases, over 90% resection in five cases, and 85% resection in one case (mean, 96%). CONCLUSION: Surgical treatment of low-grade gliomas under intraoperative MR guidance provides improved resection results with maximal patient safety.     

Simulation of anisotropic growth of low-grade gliomas using diffusion tensor imaging.

A recent computational model of brain tumor growth, developed to better describe how gliomas invade through the adjacent brain parenchyma, is based on two major elements: cell proliferation and isotropic cell diffusion. On the basis of this model, glioma growth has been simulated in a virtual brain, provided by a 3D segmented MRI atlas. However, it is commonly accepted that glial cells preferentially migrate along the direction of fiber tracts. Therefore, in this paper, the model has been improved by including anisotropic extension of gliomas. The method is based on a cell diffusion tensor derived from water diffusion tensor (as given by MRI diffusion tensor imaging). Results of simulations have been compared with two clinical examples demonstrating typical growth patterns of low-grade gliomas centered around the insula. The shape and the kinetic evolution are better simulated with anisotropic rather than isotropic diffusion. The best fit is obtained when the anisotropy of the cell diffusion tensor is increased to greater anisotropy than the observed water diffusion tensor. The shape of the tumor is also influenced by the initial location of the tumor. Anisotropic brain tumor growth simulations provide a means to determine the initial location of a low-grade glioma as well as its cell diffusion tensor, both of which might reflect the biological characteristics of invasion.     

Role of Tc-glucoheptonic acid brain single photon emission computed tomography in differentiation of recurrent brain tumour and post-radiation gliosis

Blood-brain barrier imaging of brain tumours is fast attracting interest now that it has been demonstrated that disruption of the blood-brain barrier is essential for uptake of all tumour-seeking agents. The aim of the present study was to differentiate recurrent tumour from post-radiation gliosis using (99m)technetium-glucoheptonate ((99m)Tc-GHA) as a tumour-seeking agent. Brain single photon emission computed tomography (SPECT) with (99m)Tc-GHA was performed in 73 patients with primary malignant brain tumours after radiotherapy, and the results were correlated with the clinical behaviour of the disease on follow up. The SPECT was suggestive of recurrent tumour in 55 patients. The clinical course was consistent with recurrence in 51 of the 55 patients. The clinical course was consistent with radiation necrosis in the remaining 21 patients, which included 17 patients with a negative SPECT and four patients with a positive SPECT study. Mean GHA index in recurrent tumour and post-radiation gliosis was 7.04 +/- 4.35 and 1.88 +/- 1.70, respectively (P = 0.0001). Mean GHA index in high-grade and low-grade glioma was 7.78 +/- 4.73 and 3.15 +/- 2.44, respectively (P = 0.001). (99m)Technetium-glucoheptonate brain SPECT is a sensitive and reliable diagnostic modality to differentiate recurrent tumour from post-radiation gliosis.     

18F-FDG and 11C-methionine PET in choroid plexus papilloma--report of three cases

Choroid plexus papilloma (CCP) is an uncommon benign neoplasm of the neuroectoderm. We present the 18F-fluoro-2-deoxy-D-glucose (FDG) and 11C-methyl-L-methionine (methionine) positron emission tomography of CPP in comparison with that of low-grade glioma. Patients were two women and one man (20, 23, and 72 years old). The Ki-67 labeling index ranged from 0.98 to 2.22%, and histologically the cases belonged to grade 2. On quantitative analysis, the tumor/normal ratio (T/N) was calculated using the standardized uptake value. Methionine T/N was significantly higher in CPP (3.24+/-0.69) than in low-grade glioma (1.23+/-0.81; p<0.01), although no clear difference could be determined for FDG T/N between the two (0.87+/-0.39, 0.75+/-0.53). These results may suggest that the metabolism of amino acid in CPP is quite different from that in low-grade glioma.     

术中MR液体反转恢复序列在低级别神经胶质瘤切除术中的应用价值

目的探讨术中磁共振成像(intraoperative MRI,iMRI)中的液体反转恢复序列(fluid attenuated inversion recovery,FLAIR)在低级别神经胶质瘤(WHOⅠ~Ⅱ级)切除术中的应用价值,从而对是否存在残留肿瘤的诊断提供帮助。方法选取18例低级别神经胶质瘤(low-grade gliomas,LGGs)患者的术中MRI,查看FLAIR图像中手术腔周围是否存在高信号,并对术前或术后复查过MRI患者的图像进行分析,比较术区周边FLAIR信号的变化情况。结果低级别神经胶质瘤切除术中手术区域边缘iMRI的FLAIR表现:1)没有FLAIR异常信号7例;2)线状FLAIR高信号(linear FLAIR hyperintensity,LFH)7例;3)结节或片状FLAIR高信号(nodular or patchy FLAIR hyperintensity,NPFH)4例。接受iMRI分析的患者的手术切缘上无FLARI异常信号中的4例术后3个月复查MRI术区周围未见异常改变;出现LFH中有4例患者在术后3个月后复查MRI,异常信号强度减低或消失。而2例NPFH随即进行了第二次手术切除,并再次行术中MRI扫描,最终组织病理学为肿瘤残留,1例NPFH未进行二次手术,半年后复查,异常信号范围增大。结论经iMRI分析的手术区域切缘可能出现FLAIR高信号,出现线状FLAIR高信号时不应误认为是残余肿瘤,而出现结节或片状FLAIR高信号时可能是残余肿瘤。iMRI FLAIR在初步判断低级别神经胶质瘤切除术术区边缘是否存在残留肿瘤方面有一定的应用价值。