软组织肿瘤的MR灌注成像与MR波谱成像的比较研究

目的 通过分析软组织肿瘤同一病例相同感兴趣区的MR灌注加权成像(MR-PWI)及MR氢质子波谱(1H-MRS)的功能影像信息,比较两者用于软组织肿瘤的定性诊断价值.方法 研究同时行MR-PWI、1H-MRS的全身各部位软组织肿瘤共40例.比较MR-PWI及1H-MRS各参数在良、恶性肿瘤中的差异,进而对2种诊断方法进行评价.所获数据采用t检验或配对四格表确切概率法分析.结果 MR-PWI良、恶性软组织肿瘤的血流量(BF)值差异有统计学意义(t=2.531,P<0.05),血容量(BV)及平均通过时间(MTT)值差异均无统计学意义(t值分别为1.587和1.732,P值均>0.05);以BF值=4.35 ml·100 mg-1·min-1为阈值,MR-PWI诊断恶性肿瘤的敏感度为81.8%(18/22),特异度为72.2%(13/18).良、恶性软组织肿瘤的时间信号曲线(TIC)类型比较:Ⅰ a型在良性肿瘤中占3/18,在恶性肿瘤中占17/22;Ⅰ b型在良性肿瘤中占12/18,在恶性肿瘤中占3/22;Ⅰ c型在恶性肿瘤中占2/22.Ⅱ型在良性肿瘤中占3/18.良、恶性软组织肿瘤的胆碱(Cho)、肌酸复合物(Cr)、脂质(Lip)值差异均无统计学意义(t值分别为1.332、1.637、1.986,P值均>0.05),而Cho/Cr比值的差异有统计学意义(t=2.927,P<0.05);以Cho/Cr比值=3.22为阈值,1H-MRS诊断恶性肿瘤的敏感度为86.4%(19/22),特异度为88.9%(16/18).1H-MRS谱线比较:18例良性及17例恶性软组织肿瘤在2.0～2.1ppm(×10-6)处均未出现异常峰,而2例恶性神经鞘瘤和3例恶性纤维组织细胞瘤均在2.0～2.1ppm处出现异常峰.MR-DWI与1H-MRS用于恶性肿瘤诊断准确度的差异无统计学意义(X2=0.125,P>0.05).结论 软组织肿瘤的MR-PWI的BF值、1H-MRS的Cho/Cr比值有利于软组织肿瘤良、恶性的鉴别;软组织肿瘤的TIC形态有助于肿瘤良、恶性的鉴别.MR-PWI和1H-MRS两者用于诊断恶性软组织肿瘤的准确度无明显差异,1H-MRS诊断恶性软组织肿瘤的敏感度和特异度较高.     

1H-MRS在卵巢肿块中的研究

目的探讨MR氢质子波谱(1H-MRS)在卵巢肿块中的应用价值,前瞻性分析各种代谢物对于卵巢肿块的鉴别作用。资料与方法对32例拟诊为卵巢肿块的患者行常规MRI及1H-MRS检查,采用点分辨单体素波谱成像,分析1H-MRS的特征波谱及对照病理结果。结果32例卵巢肿块波谱各有其特点,其中胆碱峰(Cho峰)出现于12例恶性肿瘤,余3例恶性肿瘤及17例良性肿块Cho峰呈阴性;乳酸峰(Lac峰)出现于4例脓肿中。以Cho峰鉴别良恶性卵巢肿块的敏感性为80%,特异性为100%;以Lac峰诊断脓肿的准确性为100%。结论1H-MRS在卵巢肿块中有一定的应用价值,其中Cho峰可作为偏实性恶性卵巢肿瘤的指标,Lac峰对于脓肿有较高的诊断率。     

磁共振氢质子波谱在下肢骨-软组织疾病中应用初探

目的 探讨磁共振氢质子波谱(^1HMRS)研究肢体骨-软组织疾病的可行性及其价值。资料与方法 对10例下肢正常骨、5例下肢正常肌肉、6例下肢良性骨病、11例下肢恶性骨肿瘤及1例下肢恶性横纹肌肉瘤进行^1HMRS测量，并采用单体素激发回波序列(SVS-STEAM)。结果 下肢骨-软组织疾病的^1HMRS波形与正常组织明显不同，良、恶性病变也存在差异，恶性病变的胆碱(Cho)含量明显升高。结论 ^1HMRS是无创性研究肢体骨-软组织疾病的生化及代谢变化的理想方法。     

磁共振波谱及扩散加权成像在唾液腺肿瘤诊断中的价值

目的 回顾性分析、评价氢质子磁共振波谱(~1H-MRS)及扩散加权成像(DWI)在鉴别唾液腺良性或恶性肿瘤中的价值.资料与方法 应用1.5 TMR成像仪,对39例唾液腺肿瘤患者进行常规MRI、DWI及~1H-MRS检查,(1)DWI采用单次激发自旋回波一回波平面成像(SE-EPI)序列,扩散敏感系数(b值)为0 s/mm~2及1000 s/mm~2,并计算每例患者平均表观扩散系数(ADC)值和高、中、低ADC值所占的比例,(2)~1H-MRS采用单体素点分辨表面线圈(PRESS)序列,TR 1500 ms,TE 136 ms,在谱线中计算胆碱与肌酸的比值(Cho/Cr).最后与肿瘤的组织病理学结果进行对比,进行非参数秩和检验.结果 39例唾液腺肿瘤患者均获得了满意的检查结果,其中良性肿瘤31例(混合瘤21例,腺淋巴瘤10例),恶性肿瘤8例(腺囊腺癌3例、黏液表皮样癌3例、混合腺癌1例、恶性淋巴瘤1例).(1)DWI:ADC图提示良性肿瘤与恶性肿瘤的平均ADC值分别为(1.65±0.41)×10~(-3)mm~2/s和(1.15±0.39)×10~(-3) mm~2/s,其间无明显差异,但良性肿瘤ADC值增高的区域则明显多于恶性肿瘤,尤其是混合瘤.(2)~1H-MRS:在TE为136 ms时共获得满意的波谱曲线35例,计算得出恶性肿瘤、腺淋巴瘤、混合瘤的Cho/Cr分别为1.69±0.51、5.89±1.42、2.81±0.72,恶性肿瘤、腺淋巴瘤、混合瘤之间均存在显著差异.结论 DWI及~1H-MRS可以作为鉴别唾液腺肿瘤的特异性检查手段,但仍需要大量研究样本来进行验证.     

在体软组织肿瘤在1.5TMR质子波谱上的特征

正摘要目的确定1H-MRS是否有助于鉴别良恶性软组织肿瘤,评价1H-MRS数据与有丝分裂指数有无相关性。方法43例软组织肿瘤直径15mm的病人接受了MR测量。6例因技术失败排除。检查采用1.5T单体素点解析波谱序列(PRESS),TR/TE=2000/150ms。感兴趣容积置于病灶内,避免纳入坏死区。所有病人     

1H-MRS联合DCE-MRI扫描在乳腺癌诊断中的临床价值

磁共振氢质子波谱(1H-MRS)中胆碱峰的升高有助于判断肿瘤的良恶性,而动态增强磁共振成像(DCE-MRI)技术可动态观察乳腺疾病的血流动力学变化,两者的联合应用有望提高乳腺癌诊断的敏感性和特异性.就1H-MRS联合DCE-MRI扫描在乳腺癌诊断中的临床价值予以综述.     

乳腺肿瘤的磁共振质子波谱评价

应用磁共振氢质子波谱（^1H-MRS）尝试研究乳腺病变波峰形态学特征,以及不同病变代谢物生化含量的差异,以提高乳腺肿瘤的确诊率。材料和方法：92例病理证实的女性乳腺病变患者,均进行了常规MRI检查和MRS测量,共计检测了248个病变部位。结果：乳腺良性病变及正常组织多含－“M”型波峰（I型）,而乳腺 瘤的^1H-MRS波形中则无（Ⅱ型）;乳腺恶性肿瘤与良性肿瘤相比,胆碱组半波宽度相差显著（P＜0．05）,且前者胆碱含量明显升高（P＜0．01）, 同时伴有肌酸含量的升高（P＜0．05）。结论：乳腺肿瘤的^1H-MRS波形与非肿瘤性病变及正常组织的MRS波形明显不同,可通过观察将两者区分开来（P＜0．01）;乳 腺恶性肿瘤的胆碱含量明显升高;^1H-MRS与MRI相配合,可以提高MRI的确诊率,不失为一种较理想的检测方法。     

40名健康青年女性乳腺组织不同回波时间的1H-MRS分析

目的 探讨MR在不同回波时间(echo times,TE)对正常乳腺组织胆碱复合物(Cho)氢质子磁共振波谱(1H-MRS)的影响,为研究正常乳腺及乳腺疾病的诊断和鉴别诊断提供客观依据.资料与方法 选择40名健康未婚青年女性自愿者,平均年龄(21.4±2.4)岁(20-24岁),所有自愿者均行常规MRI,在其基础上选择感兴趣区(ROI)并行二维1H-MRS检查,TR为1500 ms,TE分别为80 m8、110 ms、135 his、270 ms,分析不同TE下健康青年女性的正常乳腺组织的1H-MRS图形,并对比不同TE是否出现Cho峰和对Cho峰阳性率的影响.结果 TE为80 ms时,探测到可辨认的Cho峰阳性率为15.0%(6/40);TE为110 ms,阳性率17.5%(7/40);TE为135 ms时,阳性率20%(8/40);TE为270 ms时,阳性率17.5%(7/40),各阳性率之间差异无统计学意义(P>0.05);在乳腺的1H-MRS检查中,TE在110～270 ms之间为探测Cho峰的最佳TE.结论 Cho峰在健康青年女性少部分乳腺组织中可探及,但仅表现为低振幅;随着TE的延长,探测到Cho峰的可能性越大,其临床应用价值有待进一步研究.     

~1H-MRS在亚急性脑梗死与低级别脑胶质瘤鉴别诊断中的应用价值

目的探讨二维多体素氢质子磁共振波谱(2D1 H-MRS)在亚急性脑梗死与低级别脑胶质瘤鉴别诊断中的应用价值。方法 20例亚急性脑梗死患者及22例低级别脑胶质瘤患者接受了2D1 H-MRS检查,观察亚急性脑梗死与低级别脑胶质瘤2D1 H-MRS胆碱峰(Cho)、肌酸峰(Cr)、N-乙酰天门冬氨酸峰(NAA)及乳酸峰(Lac)的变化,并统计分析Cho/Cr、NAA/Cr、NAA/Cho比值。结果与对侧或邻近相对正常脑组织比较,亚急性脑梗死病例Cho峰呈轻度降低或升高,低级别脑胶质瘤病例Cho峰升高,两组病例NAA峰均不同程度降低,Cho/Cr、NAA/Cr、NAA/Cho三个比值在亚急性脑梗死与低级别脑胶质瘤之间的差异均有统计学意义(P0.05)。结论 2D1 H-MRS在亚急性脑梗死与低级别脑胶质瘤的鉴别诊断中有重要的临床应用价值。     

MR波谱能鉴别子宫内膜癌吗?

正摘要目的研究胆碱复合物(Cho)水平的三维氢质子波谱(1H-MRS)在鉴别子宫内膜癌(ECa)与子宫内膜或黏膜下良性病变(BLs-ESm)中的作用,评估Cho水平与ECa侵袭性     

In vivo characterisation of soft tissue tumours by 1.5-T proton MR spectroscopy

Objectives

To determine whether proton magnetic resonance spectroscopy (1H-MRS) can help differentiate between benign and malignant soft tissue lesions, and to assess if there is a correlation between 1H-MRS data and the mitotic index.

Methods

MR measurements were performed in 43 patients with soft tissue tumours >15 mm in diameter. Six cases were excluded for technical failure. Examinations were performed at 1.5 T using a single-voxel point resolved spectroscopy sequence (PRESS) with TR/TE = 2000/150 ms. The volume of interest was positioned within the lesion avoiding inclusion of necrotic regions. In all patients, a histological diagnosis was obtained and the corresponding mitotic index was also computed. 1H-MRS results and histopathological findings were compared using the chi-squared test and correlation coefficient.

Results

Choline was detected in 18/19 patients with malignant tumours and in 3/18 patients with benign lesions. The three benign lesions included one desmoid tumour, one ossificans myositis and one eccrine spiradenoma. Choline was not detected in 15 patients with benign lesions or in one patient with dermatofibrosarcoma protuberans. Resulting 1H-MRS sensitivity and specificity were 95% and 83% respectively.

Conclusions

Absence of choline peak is highly predictive of benign tumours suggesting that 1H-MRS can help to differentiate malignant from benign tumours.

Key Points

• 1H-MRS may allow differentiation between benign and malignant soft tissue lesions

• Absence of choline peak is highly predictive of benign soft tissue lesions

• Malignant tumours with a mitotic index >2/10 HPF had a positive choline peak

• A choline peak may still be identified in some benign tumours

     

MR imaging of primary bone and soft tissue tumors

MR imaging of 131 cases with pathologically confirmed primary bone and soft tissue tumors were studied. They included 44 bone tumors (25 benign tumors, 19 malignant tumors) and 87 soft tissue tumors (55 benign tumors, 32 malignant tumors). MR imaging was performed on 0.5T, superconductive magnet system. All tumors were evaluated with T1-weighted, T2-weighted and STIR images. In some cases, contrast enhanced MR imaging with Gd-DTPA was applied. MR imaging was proving to be a valuable technique in the evaluation of patients with primary bone and soft tissue tumors. MR imaging was superior to the other modalities in delineating the extent of the tumor and their relation to surrounding structures in all cases. However, plain radiography and CT were more useful for evaluation of calcification, ossification, cortical destruction and endosteal/periosteal reaction than MR imaging. Direct sagittal and coronal images from MR imaging added accurate assessment for the relation between the tumor and their adjacent structures. MR imaging was of limited value in distinguishing benign from malignant tumors with the demonstration of tumor structures only, especially soft tissue tumors. But in bone and soft tissue tumors which have specific morphologic features and intensity patterns, MR imaging was very useful for diagnosis.     

MR imaging of edema accompanying benign and malignant bone tumors

To evaluate the incidence, quantity, and presentation of intra- and extraosseous edema accompanying benign and malignant primary bone lesions, the magnetic resonance (MR) studies of 63 consecutive patients with histologically proven primary bone tumors were reviewed. MR scans were assessed for the presence and quantity of marrow and soft tissue edema and correlated with peroperative findings, resected specimens and follow-up data. The signal intensity and enhancement of tumor and edema prior to and after intravenous administration (if any) of gadolinium-labled diethylene triamine pentaacetate (Gd-DTPA) was analyzed. Marrow edema was encountered adjacent to 8 of 39 malignant tumors and 14 of 24 benign lesions. Soft tissue edema was found accompanying 28 of 39 malignancies and 10 of 24 benign disorders. On unenhanced T1-weighted MR images tumor and edema were difficult to differentiate. Tumor inhomogeneity made this differentiation easier on T2-weighted sequences. In 36 patients the contrast medium Gd-DTPA was used. Edema was present in 27 of these patients and the respective enhancement of tumor and edema could be compared. Edema always enhanced homogeneously, and in most cases it enhanced to a similar degree as or more than tumor. Marrow and, more specifically, soft tissue edema is a frequent finding adjacent to primary bone tumors. The mere presence and quantity of marrow and soft tissue edema are unreliable indicators of the biologic potential of a lesion. Unenhanced MR scans cannot always differentiate between tumor and edema, but the administration of Gd-DTPA is of assistance in differentiating tumor from edema. Awareness of marrow and/or soft tissue edema adjacent to bone lesions is of importance because edema can be a pitfall in the diagnostic work-up and staging prior to biopsy or surgery.     

面颊部软组织异常影像分析

目的提高对面颊部软组织异常影像的认识。方法回顾分析47例面颊部软组织异常患者的影像表现。结果(1)原发于面颊部软组织病变15例,良性8例,恶性7例。邻近颌面部病变侵犯面颊软组织6例,良性1例,恶性5例。颌骨病变累及面颊部软组织26例,良性颌骨肿瘤9例,恶性颌骨肿瘤14例,颌骨慢性骨髓炎3例,均有骨质破坏。(2)根据起源部位,21例非颌骨源性面颊软组织异常,5例有骨质破坏(占23.8%)。(3)颌骨源性面颊部软组织异常26例,其中9例良性肿瘤的软组织肿块均主要局限于颌骨内,而14例恶性肿瘤的软组织肿块位于颌骨内、外,两者差别有显著意义(P=0.000)。9例良性肿瘤均呈膨胀性骨破坏,14例恶性肿瘤中,12例为溶骨性骨质破坏,2例为成骨性骨质破坏,两者差别有显著意义(P=0.000)。结论CT和MRI对判断面颊部软组织异常病变的起源部位、范围、鉴别其良恶性具有重要意义。     

Characterization of bone and soft-tissue tumors with in vivo 1H MR spectroscopy: initial results

PURPOSE: To determine if in vivo detection of choline by using hydrogen 1 (1H) magnetic resonance (MR) spectroscopy with dynamic contrast material-enhanced MR imaging can help differentiate between benign and malignant musculoskeletal tumors. MATERIALS AND METHODS: MR imaging was performed in 36 consecutive patients with bone and soft-tissue tumors larger than 1.5 cm in diameter. Examinations were performed at 1.5 T with a surface coil appropriate for the location of the lesions. Single-voxel 1H MR spectroscopy was performed by using a point-resolved spectroscopic sequence with echo times of 40, 135, and 270 msec. The volume of interest within lesions was positioned on the areas of early enhancement (<8 seconds after arterial enhancement) according to the findings of dynamic contrast-enhanced MR imaging with subtraction. The criterion for determining whether choline was present in a lesion was a clearly identifiable peak at 3.2 ppm in at least two of the three spectra acquired at echo times. MR spectroscopic results and histopathologic findings were determined in blinded fashion and compared with kappa statistics. P <.001 was considered to indicate a significant difference. RESULTS: Choline was detected in 18 of 19 patients with malignant tumors and in three of 17 patients with benign lesions. The three benign lesions included one perineurioma, one giant cell tumor, and one abscess. Choline was not detected in 14 patients with benign lesions nor in one patient with a densely ossifying low-grade parosteal osteosarcoma. In vivo 1H MR spectroscopy characterized bone and soft-tissue tumors, resulting in a sensitivity of 95%, specificity of 82%, and accuracy of 89% (P <.001). CONCLUSION: Choline can be reliably detected in large malignant bone and soft-tissue tumors by using a multiecho point-resolved spectroscopic protocol. 1H MR spectroscopy can help differentiate malignant from benign musculoskeletal tumors by revealing the presence or absence of water-soluble choline metabolites.     

MR氢质子波谱在乳腺肿块应用中的价值及技术干扰因素分析

目的探讨MR氢质子波谱(1H-MRS)在乳腺肿块中的应用价值及技术干扰因素。方法回顾性分析手术后经病理证实的47个乳腺肿块的1H-MRS特征。其中恶性肿瘤24个,良性肿瘤23个,均于增强扫描前行1H-MRS检测。结果24个恶性病灶中11个于3.24ppm(×10-6)处出现胆碱(Cho)共振峰。23个良性病变中4个于3.24ppm处出现Cho共振峰。以1H-MRS Cho峰鉴别乳腺肿块良恶性,敏感性为45.8%,特异性为82.6%。结论1H-MRS检测到Cho并非乳腺恶性病变的特异表现。不论良性或恶性病变,只要在短期内迅速生长,1H-MRS即可测得Cho。检出率较低的原因主要为技术因素。     

1.5 T在体兔正常肌肉及VX2软组织肿瘤1H-MRS成像技术研究

目的探讨1．5T磁共振仪行在体兔正常肌肉及VX2软组织肿瘤氢质子磁共振波谱（^1H-MRS）检查的可行性及成像技术。材料与方法20只新西兰大白兔。右大腿近段肌肉内注射VX2肿瘤组织悬液0．2ml,制成肿瘤模型。分别于接种前及接种后第40d行正常大腿肌肉及肿瘤MRI和^1H-MRS成像。波谱成像序列包括单体素和多体素点解析频谱（PRESS）序列,比较不同成像条件及参数下^1H-MRS曲线,在工作站上测量胆碱（Cho）／肌酸（Cr）及脂质峰（Lipid）／Cr比值并进行统计学分析。结果所有兔正常肌肉及VX2肿瘤^1H-MRS可见Cho峰、Cr峰及Lipid峰。与正常肌肉组织相比,VX2肿瘤组织Cho峰明显增高,Lipid峰降低。肿瘤组织与正常肌肉Cho／Cr及Lipid／Cr比值差异具有统计学意义。所有兔正常肌肉和VX2肿瘤的单体素PRESS序列成像质量优于多体素PRESS序列,冠状面定位优于横断面。单体素PRESS序列半高带宽（FWHM）小于8Hz,多体素FWHM小于12Hz,成像质量较好。根据采集兴趣区大小,词整视野或采集次数可提高波谱成像质量。实时测定兔体温并设定为波谱成像时的系统温度值可有效避免波峰漂移。结论在体^1H-MRS检查兔VX2软组织肿瘤与正常肌肉^1H-MRS表现明显不同^1H-MRS有望用于软组织肿瘤的诊断。优化成像条件与参数可明显提高波谱成像质量。     

高场磁共振1H-MRS在乳腺肿瘤定性诊断中的临床应用价值

目的 探讨高场磁共振1 H-MRS在乳腺肿瘤定性诊断中的临床应用价值及影响因素.方法 收集我院经手术病理或穿刺活检病理证实的乳腺肿瘤患者160例,共计172个肿瘤作为研究组,其中乳腺癌93个,良性肿瘤79个.全部病例均于术前行磁共振动态增强后1 H-MRS检查,回顾性分析本组病例的1 H-MRS表现及MRI诊断,并将MRI诊断结果与病理结果进行对比分析.结果 93个乳腺癌病灶中78个出现胆碱(Choline,Cho)峰.79个良性肿瘤中6个出现Cho峰.以3.23ppm处出现Cho峰(SNR≥2)为乳腺癌的诊断标准,其诊断的敏感性为83.9％,特异性为92.4％,准确率为87.8％,阳性预测值为92.9％,阴性预测值为83.0％.结论 高场磁共振1 H-MRS对乳腺癌的诊断敏感性和特异性较高,在乳腺肿瘤的定性诊断中有重要应用价值.     

肋骨原发性骨肿瘤的影像学诊断(附18例分析)

目的探讨影像学对肋骨原发性骨肿瘤的诊断价值及临床应用的意义。材料与方法本组中18例摄取正侧位平片,8例加摄斜位片,2例加体层摄影,2例行CT检查。结果12例良性病变平片显示与肋骨长轴一致的囊性破坏者10例,4例伴有砂粒状钙化,6例恶性肿瘤均显示边界清楚的溶骨性破坏,CT显示软组织肿块突人胸腔。结论分析本组病例,表明X线平片对肋骨肿瘤多数可判断良恶性,CT在显示肿瘤骨质破坏及软组织肿块与邻近组织的关系方面优于X线平片。