提高脑转移瘤检出率的MRI序列优化研究

发布时间：2018-06-24 01:01

本文选题：磁共振成像 + 脑肿瘤　；参考：《重庆医科大学》2014年硕士论文

【摘要】：第一部分脑转移瘤的MRI特征研究目的探讨脑转移瘤磁共振成像（magnetic resonance imaging,MRI）的特征性表现，以提高脑转移瘤检出的准确率。方法对原发灶经病理证实的68例脑转移瘤患者，均行磁共振常规MRI平扫及增强扫描，观察并记录脑转移瘤的发生部位、大小、数目、形态、强化特点、瘤周水肿及周围组织受累情况等特征，分析脑转移瘤在MRI各序列上的表现及检出率。结果68例脑转移瘤各序列共检出867个病灶。单发脑转移瘤19例(19/68,27.94%)，多发转移瘤46例(46/68,67.65%)，颅骨转移3例(3/68,4.41%)；发生在幕上转移者38例(38/68,55.88%)，额叶最多见，幕下转移者2例(2/68,2.94%)，幕上幕下均有转移者25例(25/68，36.76%)。其中，有瘤周水肿者49例；伴囊变、坏死者56例，出血者11例；伴脑膜转移者22例。平扫：T1WI检出165个（165/867,19.38%），其中高信号为36个（36/165,21.82%），余病灶多为等或低信号；T2WI、T2-FLAIR、DWI，病灶多为等或高信号。增强扫描：增强T1WI检出病灶867个（867/867,100%）。强化方式：结节型强化541个，环形强化为223个，，混合型强化为103个。单发脑转移瘤病灶大小为0.50～5.77cm，平均2.43cm±1.48cm，其表现与脑转移瘤的共同特征相符。结论研究脑转移瘤MRI特征性表现，有利于脑转移瘤的诊断及鉴别诊断，可提高脑转移瘤的检出率及诊断的准确率。第二部分脑转移瘤的MRI序列优化研究目的探讨MRI常规序列、T1加权三维成像（three-dimensional T1weighted imaging,3D-T1WI）序列诊断脑转移瘤的价值，优化脑转移瘤MRI扫描方案。方法收集原发灶经病理证实的35例脑转移瘤患者，均行MR常规序列及3D-T1WI平扫和增强扫描，分析各序列对脑转移瘤的检出率，并对比常规扫描方案与优化扫描方案的扫描时间。结果35例脑转移瘤各序列共检出609个病灶；平扫T1WI序列检出病灶101个（101/609,16.58%）， T2WI序列检出155个（155/609,25.45%），T2-FLAIR序列检出235个（235/609,38.59%），DWI（b=0）序列检出176个（176/609,28.90%），3D-T1WI序列检出228个（228/609,37.44%）；增强T1WI序列检出427个（427/609,70.11%），增强3D-T1WI序列检出609个（609/609,100%）；其中病灶直径1.0cm者547个，直径为1.0~3.0cm者60个，直径3.0cm者2个；有瘤周水肿者263个；常规方案MRI扫描共用时638s，优化后3D-T1WI序列扫描方案用时575s。平扫及增强3D-T1WI序列对脑转移瘤的检出率明显高于平扫及增强T1WI序列(p均＜0.05)；DWI（b=0）序列与T2WI序列对脑转移瘤的检出率差异无统计学意义（p＞0.05）。结论3D-T1WI序列及增强扫描的运用，可显著提高脑转移瘤的检出率，尤其对于＜1.0cm且未见明确瘤周水肿的转移灶，其诊断意义更大。优化脑转移瘤磁共振扫描方案，可用3D-T1WI序列替代常规T1WI序列扫描，DWI（b=0）序列替代T2WI序列，以提高脑转移瘤检出率，缩短扫描时间。
[Abstract]:Part I MRI features of brain metastases objective to investigate the (magnetic resonance imaging features of brain metastases in order to improve the accuracy of detection of brain metastases. Methods Sixty-eight patients with brain metastases confirmed by pathology were examined with conventional MRI and enhanced MRI. The location, size, number, morphology and enhancement of brain metastases were observed and recorded. The features of peritumoral edema and surrounding tissue involvement were analyzed and the MRI findings and detection rate of brain metastases were analyzed. Results A total of 867 lesions were detected in 68 cases of brain metastases. There were 19 cases of single brain metastases (19 / 68 27.94%), 46 cases of multiple metastases (46 / 6867.65%), 3 cases of skull metastases (3 / 686.41%), 38 cases of supratentorial metastases (38 / 68 / 55.88%), 2 cases of subtentorial metastasis (2 / 68 / 2.94%) and 25 cases of subtentorial metastases (25 / 6836.76%). Among them, there were 49 cases with peritumoral edema, 56 cases with cystic degeneration, 11 cases with hemorrhage and 22 cases with meningeal metastasis. 165 cases (165 / 867 / 19.38%) were detected on T1WI, of which 36 were hyperintense (36 / 165 / 21.82%), others were iso-or hypointense T2WIMr T2-FLAIRDWI, and most of the lesions were isointense or hyperintense. Enhanced scan: 867 lesions were detected on T 1WI (867 / 867100%). Enhancement pattern: 541 nodular enhancement, 223 ring enhancement and 103 mixed enhancement. The lesion size of single brain metastases was 0.50 ~ 5.77 cm (mean 2.43cm 卤1.48 cm), which was consistent with the common features of brain metastases. Conclusion studying MRI features of brain metastases is helpful to the diagnosis and differential diagnosis of brain metastases, and can improve the detection rate and diagnostic accuracy of brain metastases. Part II study on MRI sequence Optimization of brain Metastases objective to evaluate the value of conventional three-dimensional T1-weighted three-dimensional imaging (three-dimensional T1-weighted imaging 3D-T1WI) in the diagnosis of brain metastases, and to optimize the MRI scanning scheme of brain metastases. Methods 35 patients with brain metastases confirmed by pathology were examined with conventional Mr sequence and 3D-T1WI plain scan and enhanced scan. The detectable rate of brain metastases was analyzed and the scanning time between conventional and optimized scanning schemes was compared. Results A total of 609 lesions were detected in 35 cases of brain metastases, 101 lesions were detected on plain T1WI (101 / 609 / 16.8%), 155 on T2WI (155 / 60925.45%) and 235 (235 / 6038.59%) by T2-flair, 176 (176p / 60928.90%) / 3D-T1WI were detected on 3D-T1WI (228r-60937.44%). 427 (427 / 609) and 609 (609 / 609100%) were detected on enhanced T1WI and 609 / 609100% on enhanced 3D-T1WI, among them, 547 lesions were 1.0cm, 60 were 1.0~3.0cm, 2 were 3.0cm, 263 were peritumoral edema. The routine MRI scan time was 638s, and the optimized 3D-T1WI sequence was 575s. The detection rate of brain metastases on plain and enhanced 3D-T1WI sequences was significantly higher than that on plain and enhanced T1WI sequences (p < 0.05). There was no significant difference in the detectable rate of brain metastases between DWI and T2WI (p > 0.05). Conclusion 3D-T1WI sequence and contrast-enhanced scan can significantly improve the detection rate of brain metastases, especially for the metastases with less than 1.0cm and without definite peritumoral edema, which is of great significance in the diagnosis of brain metastases. In order to improve the detection rate and shorten the scanning time of brain metastases, 3D-T1WI sequence can replace the conventional T1WI (bt0) sequence instead of T2WI sequence.
【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R445.2

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