MRI检查方案对子宫及卵巢肿瘤诊断价值分析

目的;分析和探讨MRI不同成像序列及扫描位置对显示正常女性盆腔结构和诊断盆腔肿瘤的价值,并进一步确定诊断子宫及卵巢肿瘤的最佳MRI检查方案。方法：对20例正常女性贫腔和40例经手术病理证实的子宫或卵巢肿瘤患者的盆腔磁共振成像检查资料进行了定量及定性分析。所有检查均采用SE T1WI及FSE T2WI序列,分别行横断、矢状及冠状面扫描。在20例患有子宫肿瘤的患者中,11例加做了与子宫腔长轴平行的冠斜位T1WI和T2WI序列扫描。结果：对于正常子宫及直肠的辨别能力,FSE T2WI图像明显好于SE T1WI图像,两者之间有显著性统计学差异。对于子宫肿瘤患者,分析子宫肿瘤与正常子宫结合带的CNR值,结果表明T2WI图像明显高于T1WI图像且两者之间有显著性统计学差异;联合应用T1WI及T2WI扫描序列在横断、矢状及冠状位对子宫肿瘤的检出准确性分别为64.3%,96.4%,53.6%,且矢状与横断及冠状位之间差异有显著性统计学意义。在11例加做与子宫腔长轴平行的冠斜位患者中,对肿瘤检出及定位,定性的诊断准确性方面,8例（73.0%)显示明显优于其他3种位置。对于卵巢肿瘤的观察结果表明：3种扫描位置的检出能力无明显显著性差异,横断,矢状及冠状位的准确性分别为100％,95％,100％,但对于恶性肿瘤是否伴有髂血管区淋巴结转移及盆壁是否侵犯的观察,横断及冠状面显示最佳。结论：T2WI序列矢状位为诊断子宫肿瘤的首选MRI检查方法,必要时辅以与子宫腔长轴平行的冠斜位;而观察卵巢肿瘤及盆壁情况,横断及冠状位为必备检查位置。     

Preoperative assessment of myometrial and cervical invasion in endometrial carcinoma: Comparison of multi-section dynamic MR imaging using a three dimensional FLASH technique and T2-weighted MR imaging

Introduction: We aimed to show the diagnostic performance of magnetic resonance imaging by comparing T2-weighted images and dynamic 3D MR images in the assessment of myometrial and cervical invasion by endometrial carcinoma. Methods: This prospective study included 53 women consecutively diagnosed with endometrial carcinoma. The subjects were evaluated by TSE T2-weighted images and 3D FLASH-VIBE dynamic MR images by two radiologists with a special training in gynecology. Sensitivity, specificity, negative and positive predictive values were calculated for each imaging modality with regard to assessment of myometrial and cervical invasion. Results: The diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR imaging for the identification of any myometrial invasion were estimated as 64% and 84%, respectively. In the differentiation of deep myometrial invasion from the superficial invasion, the diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR images were 75.5%, and 88.7%, respectively. Additionally, in the determining of deep myometrial invasion the sensitivity, the specifity, PPV, and NPV were 76%, 75%, 50%, and 90.9% on T2-weighted images, respectively; 100%, 85%, 68.4%, and 100% on dynamic 3D MR images, respectively. The diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR images for cervical invasion by endometrial carcinoma were 86%, and 92%, respectively. Conclusion: The multiplanar capabilities of MRI are invaluable to evaluate spreading and margins of an endometrial mass, and the 3D dynamic MR techniques offer the advantages of increased coverage and high spatial resolution. Three dimensional dynamic MR imaging may be recommended in the especially postmenouposal cases before performing potentially curative treatments.     

胰头癌与胰头慢性胰腺炎的MR诊断与鉴别诊断

目的探讨胰头癌及胰头慢性胰腺炎的MR诊断与鉴别诊断。方法回顾性分析24例胰头癌及3例胰头慢性胰腺炎的MR表现。全部27例病人均行常规及压脂SET1WI序列、常规及压脂FSET2WI序列扫描。8例胰头癌及3例胰头慢性炎症患者行压脂SET1WI序列增强扫描。T2WI序列发现胰管扩张时行MRCP共24例,其中胰头癌23例,慢性胰腺炎1例。结果24例胰头癌于常规SET1WI序列呈低(n=8)或稍低(n=16)信号,于常规FSET2WI序列可表现为高(n=8)、稍高(n=5)、等(n=10)或低(n=1)信号,于压脂FSET2WI序列可表现为高(n=11)、等(n=11)或稍低(n=2)信号,于压脂SET1WI序列均呈低信号。23例胰头癌于MRCP均可见典型的“双管征”、胆总管扩张及远端截断。8例胰头癌无明显强化。3例胰头慢性胰腺炎于常规SET1WI序列呈稍低或等信号,于常规FSET2WI序列均呈高信号。2例于压脂SET1WI及FSET2WI序列分别呈等信号及稍高信号,另1例则分别呈低信号及混杂信号,MRCP可见胆总管轻度扩张伴胰管近端不规则扩张。3例慢性胰炎均呈不同程度强化。结论胰头癌与胰头慢性胰腺炎均于多个序列表现出信号的多样性,均可见异常强化,绝大多数胰头癌及部分胰头慢性胰腺炎有异常的MRCP表现。联合使用多种序列特别是平扫及增强压脂SET1WI序列及MRCP,可能鉴别胰头癌与胰头慢     

Carcinoma of the cervix: Value of dynamic magnetic resonance imaging in assessing early stromal invasion

Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.     

腰椎间盘突出症2D-FIESTA Cine成像的临床应用

目的 评价2D-FIESTA cine成像在腰椎间盘突出症中的临床应用价值.方法 18例腰椎间盘突出症患者分别行矢状位SE T1WI,快速SE(FSE)T2WI,脂肪抑制FSE T2WI(fat saturation FSE T2WI,FS-FSE T2WI)及2D-FIESTA(fast imaging employing steady-state acquisition,FIESTA)cine.回顾性分析18例经手术病理或随访证实腰椎间盘突出症的2D-FIESTA cine表现,并与其他常规序列的MR扫描时间进行比较.结果 18例腰椎间盘突出症患者,共33个椎间盘受累.在SE T1WI上,病变均呈低信号,FS-FSE T2WI、FSE T2WI和FIESTA呈中等信号或低信号.2D-FIESTA cine除可动态显示突出椎间盘的情况,并可清楚显示受压的脊神经.2D-FIESTA的扫描时间仅为T2WI的13.3%;为T1WI的17.9%.2D-FIESTA的扫描时间比常规MRI扫描时间短(P＜0.001).结论 2D-FIESTA cine能清楚提供诊断腰椎间盘突出症的有价值的表现,是常规MR检查的有效补充.     

子宫颈癌术前磁共振成像诊断与术后病理分期对比分析

 目的　探讨磁共振成像（MRI）术前分期的准确性与病理分期的准确性,以及对子宫颈癌治疗方式的指导价值。方法　回顾性分析50例子宫颈癌患者（鳞癌47例,腺癌2例,鳞腺癌1例）的临床及MRI资料。所有患者行平扫及增强扫描,23例行三期动态增强扫描。38例经手术治疗的患者,对术前MRI分期与术式的选择及术后病理分期进行对照分析。结果　33例MRI分期为Ⅰ～ⅡA期子宫颈癌分期准确率约为82.35 %,患者行子宫全切术及盆腔淋巴结清扫术。ⅢA～ⅣB期的诊断准确率约100 %。MRI对子宫颈癌分期总的准确率约为84.21 %。结论　MRI能多方位显示子宫颈癌病灶及其侵犯范围,术前分期具有较高的准确性,有利于术前评估、手术方式的制定及治疗方案的选择。     

宫颈癌放射治疗疗效的MRI评价

目的分析宫颈癌放射治疗中与后MRI表现,探讨MRI成像对宫颈癌放射治疗疗效评估的价值。方法23例经病理证实的宫颈癌患者在放射治疗前、中及后不同时间段行盆腔的轴位T1WI,轴位及矢状位T2WI,冠状位SPIR,以及GDDTPA增强后T1WI的轴位、冠状位、矢状位扫描。在MRI图像上观察肿瘤在放射治疗前、后的大小及信号改变。结果外照射结束时,9例肿瘤缩小率在85%以下,14例>85%。T1WI增强扫描7例见肿瘤内出现“无强化区”,其中6例放射治疗结束后有肿瘤残留;16例肿瘤未见“无强化区”,其中13例肿瘤缩小率>85%,仅2例放射治疗后有肿瘤残留。MRI图像上,肿瘤痊愈表现为T2WI、SPIR序列呈低信号,T1WI增强扫描轻微强化或无强化。结论MRI成像可反应肿瘤对射线的疗效。外照射结束时肿瘤容积缩小程度与T1WI增强肿瘤内有无“无强化区”是预测放射治疗效果的重要观测指标。     

富血供肝转移瘤的MRI表现和特点

背景与目的：肝脏是血源性转移癌最好发的器官，正确判断富血供肝转移瘤具有重要的临床价值，本研究探讨富血供肝转移瘤的MRI特征。方法：回顾性分析122例有明确原发肿瘤病史并伴有肝脏转移的病例。根据强化程度，当病灶显示出明显的早期强化（强化程度与胰腺或肾皮质相仿）时，肝转移瘤被认为是富血供的，据此，共有31例符合人选标准，其中男性8例，女性23例，年龄29～77岁，平均年龄51．9岁。所有31例均行上腹部MRI检查（采用1．5T超导MR扫描仪），扫描序列包括T2WIFSE序列，T1WISPGR序列（用于增强前后扫描）。对比剂为钆喷酸葡胺注射液（Gd—DTPA），注射剂量为0．1mmol/kg，注射速率为2ml／s，注射后行Ⅲ期扫描，扫描时间分别为：20、45、90S。所有MR图像由两位有经验的放射科高年主治医师分析并达成一致。结果：31例患者共发现239个肝转移灶，分布于两叶，无特别好发肝段。其中21例转移灶为多发，其余10例为单发转移灶。病灶小于9．5cm。MR图像显示所有病灶于T1WI均为低信号。在T2WI图像上，127个病灶（53％）显示为中等高信号，65个病灶（27％）为中等高信号伴病灶中央更高信号区。增强动脉期显示183个病灶（77％）呈明显的边缘强化，41个病灶（17％）呈弥漫均匀的结节样强化，15个病灶（6％）呈弥漫不均匀强化。增强门脉期，131个病灶表现为与动脉期相仿的强化方式与程度，其中33个病灶表现为较动脉期稍增厚的强化环。结论：根据富血供肝转移瘤的主要特征．大多数病灶可以和肝脏其他富血供病变（如HCC．血管瘤，FNH等）能正确鉴别。     

Endometrium-myometrium Ratio: A Newly Proposed Diagnostic Parameter on Magnetic Resonance Imaging Assessment of Myometrial Invasion by Endometrial Cancer

In order to improve the accuracy of magnetic resonance (MR)imaging assessment of myometrial invasion by endometrial cancer,the usefulness of a new diagnostic parameter, the endometriummyometrium(EM) ratio has been evaluated. EM ratio is the proportion ofthe widest length of endometrium to the length of myometriummeasured at the same line, this being vertical to the parallelof the long axis of the uterine body in the sagittal plane ofthe MR images. Myometrial invasion was defined as a value ofthe EM ratio > 1 , and the tumor was limited to the endometriumfor values < 1 . In 25 consecutive patients, both the EMratio-based assessment and the well-established junctional zone-basedasessment with T2-weighted MR imaging and enhanced MR imagingwith gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA)were compared with the results from pathological examinationsof postoperative specimens. In identifying moymetrial invasionby endometrial cancer, the sensitivity of the EM ratio-basedassessment was better than that of the junctional zone-basedassessment. The overall sensitivity of the former was 96% inboth the T2-weighted and enhanced MR imaging with Cd-OTPA, whereasthat of the latter was 84% in the T2-weighted MR imaging and72% (P<0.05) in the enhanced MR imaging. The use of the EMratio with MR imaging improves the ability to assess myometrialinvasion by endometrial cancer.     

鼻咽癌海绵窦侵犯的MRI评价

目的探讨鼻咽癌侵犯海绵窦的发生率、主要侵犯途径及MRI特点。方法经病理证实并经MRI检查的鼻咽癌患者141例,使用1．5T超导MR机进行检查,增强扫描前行快速自旋回波（FSE）序列横断面T1WI、T2WI扫描,增强后采用快速扰相梯度回波（FSPGR）脂肪抑制序列横断面及冠状面扫描。由两位经验丰富的放射科医师读片。结果141例患者中,有39例（49侧）海绵窦受侵犯,发生率为27．7％。卵圆孔为最常见的单一侵犯途径,有18侧仅通过卵圆孔侵犯海绵窦,占36．7％;多途径侵犯海绵窦的患者中,有6侧（12．2％）经卵圆孔与破裂孔侵犯海绵窦,为最常见共同途径。最常见的MRI表现为海绵窦增大伴异常强化（22侧）,其次为海绵窦壁局限性或弥漫性增厚和（或）海绵窦内血管、神经结构紊乱或模糊不清（18侧）,海绵窦局部形成肿块者9侧。结论卵圆孔是鼻咽癌侵犯海绵窦的主要途径。MRI能有效、准确地判断鼻咽癌侵犯海绵窦的情况,对指导临床采取正确治疗措施具有重要价值。     

Value of MR imaging in the staging of rectal carcinoma]

Correlative studies of MRI and pathologic specimens were done in 35 patients with rectal cancer. The MR manifestations of the primary tumor and its invasion into the surrounding structures were investigated with reference to the staging of rectal cancer. Prone positioning and the procedure of hypotonic air-distension of rectum was the method of choice to depict the primary tumor and tumor invasion. The spin-echo (SE)pulse sequence with TR/TE: 500/32 ms (T1-weighted image) was selected to show the anatomical structures in the pelvis and tumor spread in the surrounding fatty space and lymph node metastasis. Owing to the reduced contrast between tumor invasion and fatty tissue and decreasing signal intensity on multi-echo T2-weighted images the long repetiting time (TR) pulse sequence could not provide significant contribution in tumor staging. The MR appearance of rectal carcinoma was categorized as polypoidnodular, cauliflowermassive and protuberant-ring types. Ulceration was often seen in the latter two types. Peripheral invasion often manifested as spotty-nodular, sawtoothed-wavy and tumefied shape with medium signal intensity on T1-weighted images. The presence of a lump of small nodes, round or oval nodules within 2 cm from the rectal wall or nodular mass in the perirectal fatty space could be considered as possible lymph node metastasis. Following the modified Dukes Staging System of rectal cancer proposed by Astler-Coller all patients were staged preoperatively and correlated with surgical specimens. The accuracy of staging was 74.3%, compatible with the results of studies published.     

Oral cavity and base of the tongue tumors. Correlation between clinical, MRI and pathological staging of primary tumor

The diagnosis of oral cavity and oropharyngeal tumors can be obtained through clinical examination and biopsy. CT and MRI can then be used to define the extension of the disease. The aim of this study was to define the accuracy of clinical and MRI T staging of oral cavity and base of the tongue tumors and correlate the results with pathological data. Mandibular involvement, in a subgroup of patients, was determined and sensitivity, specificity, accuracy and positive and negative predictive values were evaluated. Fifty-nine patients affected by squamous cell carcinoma and 1 case of adenoido-cystic carcinoma were examined by means of a superconductive MR unit, using SE T1, and fat-suppressed T2 weighted sequences before contrast medium infusion. SE T1 and T1 fat-suppressed sequences after gadolinium-DTPA infusion were used. T stage accuracy of both clinical examination and MRI were found to be respectively 62% (k 0.459) and 82% (k 0.775). The sensitivity, specificity and accuracy of MRI in the detection of mandibular involvement were 94.1%, 60% and 81.5%, while the positive and negative predictive values were 80% and 85.7%, respectively. The sensitivity, specificity and accuracy of clinical examination in the detection of mandibular involvement were 100%, 30% and 74.1%, while the positive and negative predictive values were 70.8% and 100%. In the present study, MRI was seen to be an adequate technique for the assessment of oral cavity malignancies, in the evaluation of depth invasion, presence and extension of mandibular involvement.     

Magnetic resonance imaging of the exocrine pancreas

The currently available MRI, techniques that are used to perform imaging of the pancreas are reviewed. A basic pancreas examination includes: fat-suppressed breath-hold T1-weighted and respiratory triggered or breath-hold T2-weighted fast sequences The use of dynamic MRI with both extracellular gadolinium chelates and specific contrast agents is stressed in the evaluation of exocrine pancreatic diseases. It is concluded that an "all-in-one" approach including MR angiography of the pancreatic vessels and MR cholangiopancreatography of the biliopancreatic ductal system, confirmed by further studies, is presumably the most cost-effective imaging technique in the evaluation of a vast array of exocrine pancreatic diseases.     

Magnetic resonance imaging of musculoskeletal lesions: Comparison of three fat-saturation pulse sequences

Fat-saturation (FS) pulse sequences can improve the detection of musculoskeletal lesions. We prospectively compared contrast-enhanced T1-weighted FS spin-echo (SE) images, T2-weighted FS fast spin-echo (FSE) images and inversion recovery (IR) FSE images to determine if any of these three pulse sequences is superior for depicting bone marrow and soft tissue lesions. T1-weighted FS-SE images (400-680/10-20 [TR/TE]) after intravenous injection of gadoliniumdiethylenetriaminepentaacetic acid (DTPA), T2-weighted FS-FSE (2400-4200/96-112) and IR-FSE (3700-6000/12-14/170 [TR/TE/TI]) images were obtained with a 1.5-T magnet system in 35 patients. The visibility, margination and extent of 37 bone marrow and 67 soft tissue lesions, image uniformity, susceptibility and motion artefacts were qualitatively analysed by four radiologists. The number and size of lesions detected, the mean lesion signal-to-noise ratio (S/N) and contrast-to-noise ratio (C/N) were also statistically compared. More bone and soft-tissue lesions were detected on the IR-FSE and T2-weighted FS-FSE than the T1-weighted FS-SE images. The IR-FSE images were significantly better than the T2-weighted FS-FSE and T1-weighted FS-SE images for bone marrow lesion conspicuity (P<0.01). The soft-tissue lesions were also more conspicuous on the IR-FSE and T2-weighted FS-FSE images than on the T1-weighted FS-SE images (P<0.005). The lesion extent and image quality were similar on all three sequences while motion artefacts were most severe on the IR-FSE and least severe on the T1-weighted FS-SE images (P<0.001). Fat saturation was maximal on the IR-FSE images, resulting in a significantly higher mean ON of bone marrow lesions. The mean C/N of soft-tissue lesions was higher on the T2-weighted FS-FSE images although the differences were not significant. The T2-weighted FS-FSE and IR-FSE sequences are superior to the contrast-enhanced T1-weighted FS-SE sequence for depicting musculoskeletal lesions. Bone marrow lesion conspicuity is greater on the IR-FSE images, with comparable scan time and image quality but more motion artifacts.     

磁共振扩散加权成像对子宫内膜癌的诊断价值

目的 应用高场强磁共振对子宫内膜癌进行扩散加权成像(DWI),并探讨其对子宫内膜癌的诊断价值.方法 应用3.0T磁共振扫描仪,对临床怀疑为子宫内膜癌的50例患者(病理证实子宫内膜癌35例,子宫内膜不典型增生10例,分泌期子宫内膜4例,萎缩性子宫内膜1例)以及41例正常志愿者行常规扫描和DWI,DWI选择b值为1000 s/mm~2.观察子宫内膜癌、正常子宫内膜和子宫内膜不典型增生在DWI图像上的差异,并分析三者间以及不同分化程度子宫内膜样腺癌之间表观扩散系数(ADC)值的差异.结果 与周围正常肌层相比,子宫内膜癌、子宫内膜不典型增生和正常子宫内膜在DWI图像上均呈明显高信号.子宫内膜癌、子宫内膜不典型增生和正常子宫内膜的ADC值分别为(1.08±0.23)×10~(-3)mm~2/s、(1.29±0.21)×10~(-3) mm~2/s和(1.41±0.21)×100~(-3)mm~2/s.统计分析结果显示,子宫内膜癌和正常子宫内膜的ADC值之间以及子宫内膜癌与子宫内膜不典型增生的ADC值之间的差异均有统计学意义(均P＜0.05),但高分化子宫内膜样腺癌和中分化子宫内膜样腺癌的ADC值之间的差异无统计学意义(P=0.109).结论 DWI对检出子宫内膜病变非常敏感,能够鉴别子宫内膜癌、子宫内膜不典型增生和正常子宫内膜,但对于鉴别不同分化程度的子宫内膜样腺癌仍有一定的困难.     

Magnetic resonance imaging during intracavitary gynecologic brachytherapy.

The cases of three patients, two with Stage III-B and one with Stage II-B carcinoma of the cervix, are cited to illustrate specific advantages of magnetic resonance (MR) imaging over computed tomography (CT) during intracavitary gynecologic brachytherapy. CT and MR were performed during the first of two intracavitary implants. To obtain artifact-free images with the intracavitary implant in place, a CT- and MR-compatible Fletcher system applicator was used. Although CT failed to differentiate the cervical tumor clearly from surrounding tissues, the area of pathology could be identified on MR by comparing the T1-weighted (T1W) and T2-weighted (T2W) images. Cervical tumors typically exhibit low-signal intensity on T1W and high-signal intensity on T2W scans, whereas paracervical soft tissues demonstrate high intensity on both T1W and T2W images. This contrast permits the size, location, and paracervical involvement of the tumor to be defined by MR. Multiplanar MR images obtained during the patients' intracavitary brachytherapy help demonstrate the actual anatomic relationship between the tumor and the applicator. Isodose distributions displayed on these images show that, in two cases, the tumor margin extended beyond the prescribed isodose line. Thus, MR may prove to be a clinically useful reference during intracavitary brachytherapy for ascertaining radiation dose to actual tumor volume.     

Current status of body MR imaging: fast MR imaging and diffusion-weighted imaging

The recent technical advances in fast MR imaging have greatly enhanced the clinical value of MR imaging of the body. Advances in T₁-weighted images have enabled the acquisition of dynamic contrast-enhanced MR imaging, which is currently central to hepatic MR imaging for detection and characterization of liver tumors and is also useful for the evaluation of myometrial invasion in uterine cor-pus cancer. Advances in rapid T₂-weighted MR imaging with single-shot fast spin-echo images have enabled MR cholangiopancreatography and MR urography. Application of respiratory triggering can also provide T₂-weighted images of high quality. Cine MR imaging utilizing ultrafast MR sequences enables the assessment of the respiratory motion of the lung for evaluating thoracic wall invasion by tumors. Diffusion-weighted images can provide excellent tissue contrast based on molecular diffusion and have the potential to demonstrate malignant tumors. Quantitative measurement of apparent diffusion coefficient values may also be valuable in distinguishing malignancies from benign lesions.     

Prediction of high-grade meningioma by preoperative MRI assessment

High-grade (World Health Organization grades II and III) meningiomas grow aggressively and recur frequently, resulting in a poor prognosis. Assessment of tumor malignancy before treatment initiation is important. We attempted to determine predictive factors for high-grade meningioma on magnetic resonance (MR) imaging before surgery. We reviewed 65 meningiomas (39 cases, benign; 26 cases, high-grade) and assessed four factors: (1) tumor–brain interface (TBI) on T1-weighted imaging (T1WI), (2) capsular enhancement (CapE), i.e., the layer of the tumor–brain interface on gadolinium-enhanced T1WI (T1Gd), (3) heterogeneity on T1Gd, and (4) tumoral margin on T1Gd. All four factors were useful in distinguishing high-grade from benign meningiomas, according to univariate analysis. On multivariate regression analysis, unclear TBI and heterogeneous enhancement were independent predictive factors for high-grade meningioma. In meningiomas with an unclear TBI and heterogeneous enhancement, the probability of high-grade meningioma was 98%. Our data suggest that this combination of factors obtained from conventional sequences on MR imaging may be useful to predict high-grade meningioma.     

188例脊柱转移瘤磁共振成像分析

（目的）分析１８８例脊柱转移瘤的ＭＲ表现，探讨其转移途径，生长方式和ＭＲＩ诊断价值，（方法）１８８例脊柱转移瘤患者均有脊柱病变区或原发肿瘤组织学证实，ＭＲ成像采用自旋回波序列，所有病例作了Ｔ１加权成像，质子密度成像和Ｔ２加权成像，４９例作了静脉注射Ｇｄ－ＤＴＰＡ后Ｔ１加权成像，（结果）１８８例共检出椎体转移７５６只，其中５９８只椎体呈现信号／形态异常，１５８例只仅呈现信号异常，９６例伴附件异常，１     

Ⅰ、Ⅱ期子宫内膜癌MRI表现与病理对照研究

Objective： To analyze MRI features of FIGO stage Ⅰ and Ⅱ endometrial carcinoma and to study the value of MRI in assessing myometrial and cervical invasion of endometrial carcinoma. Methods： Thirty patients with surgicopathologically proven endometrial carcinoma were included in this retrospective study. All patients underwent Tl-weighted spin-echo, T2-weighted fast spin-echo and dynamic contrastenhanced fast multiplanar spoiled gradient echo sequences before surgery. The type, signal intensity and enhancement features of the tumors and the appearance of junctional zone or subendometrial enhancement were analyzed. The MRI diagnosis of myometrial and cervical invasion was correlated with pathologic findings.Results： Endometrial carcinoma demonstrated diffuse widening of endometrial stripe （n=14） or polypoid or large mass in the endometrial cavity （n=16）. The tumors were usually isointense relative to the myometrium on TlWI and hyperintensity on T2WI. In the first phase of dynamic contrast-enhanced sequences, diffuse endometrial carcinoma usually showed mild （n=8） or moderate （n=5） enhancement, while focal endometrial carcinoma tended to enhance markedly （n=6） or moderately （n=9）. On T2WI junctional zone was seen in 18 cases. On dynamic contrast-enhanced images subendometrial enhancement was seen in 17 cases. The sensitivity, specificity and diagnostic accuracy of dynamic contrast-enhanced images in combination with T2WI were 87.5%, 95.5% and 93.3% for assessing deep myometrial invasion, and 75%, 95.5% and 90% for assessing cervical invasion. Conclusion： MRI is accurate and reliable in the evaluation of myometrial and cervical invasion of endometrial carcinoma, and should be performed as preoperative routine examination.