Dedifferentiated chondrosarcoma of the appendicular skeleton: MRI-pathological correlation

Objective To correlate the T2-weighted and STIR MRI appearances of dedifferentiated appendicular chondrosarcoma with gross and microscopic pathology.Design and patients Nine patients with a histologically confirmed diagnosis of dedifferentiated appendicular chondrosarcoma were identified from the Bone Tumour Registry. All patients underwent MRI, including T2-weighted and/or STIR sequences in at least one plane, prior to limb salvage surgery. Areas of reduced signal intensity (SI) compared with hyperintense chondral tumour on the T2-weighted or STIR images were correlated with the resection specimen, to determine the relationship of such out areas of reduced SI with regions of dedifferentiation.Results and conclusions Patients presented over a period of 7 years. There were five men and four women with mean age 68.2 years and age range 51–78 years. Tumours arose in the femur (6 cases), humerus (2 cases) and tibia (1 case). Three MRI patterns were identified: (1) type 1, a lesion with two distinct signal characteristics—hyperintense chondral and reduced SI dedifferentiated tumour (n=6); type 2, mainly reduced SI lesion—dedifferentiated tumour, with areas of signal void corresponding to matrix calcification (n=2); type 3, a heterogeneous lesion with no radiological evidence of underlying chondral tumour (n=1). T2-weighted or STIR MR sequences can identify areas of dedifferentiation, which should be the preferential site of pre-operative biopsy.     

软骨肉瘤的影像诊断与鉴别诊断

目的:探讨软骨肉瘤的影像学表现,提高对本病诊断的准确性。方法:回顾性分析25例经手术病理证实的软骨肉瘤的X线、CT和MRI资料。结果:25例软骨肉瘤中原发23例,其中普通型20例,去分化型、黏液型及透明细胞型各1例;继发2例。X线及CT表现:原发的23例中溶骨性骨破坏5例,混合性骨破坏18例,形成软组织肿块20例,其中表现为低密度19例,等密度1例。20例普通型及1例黏液型见散在钙化。MRI表现:普通型软骨肉瘤T1WI呈等或稍低信号,T2WI呈等或稍高信号;黏液型T1WI呈等、低混杂信号,T2WI呈稍高、低的混杂信号,钙化T2WI呈低信号;透明细胞型病例T1WI及T2WI呈近乎等信号;去分化型T1WI呈等低混杂信号,T2WI呈不均匀高信号。6例普通型及1例继发型出现环形、间隔样中等-明显强化,黏液型及去分化型呈不均匀中等-明显强化。结论:普通X线及CT是软骨肉瘤影像诊断及鉴别诊断的主要手段,MRI显示软骨信号为重要提示。MRI显示病变范围更为清楚、准确,为临床治疗提供可靠依据。     

原发性软骨肉瘤的影像诊断

目的探讨原发性软骨肉瘤影像特点及诊断要点。方法回顾性分析13例病理证实的原发性软骨肉瘤的X线、CT、MRI表现,并与病理对照。结果13例中,常见型9例,黏液型3例,去分化型1例。发病部位：长骨7例（股骨6例,肱骨上端1例）,躯干骨6例（骨盆3例,肋骨2例,胸椎1例）。X线及CT表现：呈斑片状、大片状溶骨性骨质破坏,周围骨质密度增高,骨皮质破坏、中断,局部软组织肿块。11例病灶内出现钙化。MRI表现：5例病灶T1WI呈稍低及等信号,T2WI呈显著高信号,增强后呈分隔状强化。结论X线、CT、MRI检查的综合运用,对原发性软骨肉瘤的诊断有重要的价值。     

MR findings of renal cortical necrosis

PURPOSE: Evaluating the MR findings of renal cortical necrosis was the purpose of this study. METHOD: Eight series of T1-/T2-weighted (n = 8) and contrast-enhanced T1-weighted (n = 4) MR images in six patients with renal cortical necrosis diagnosed by renal biopsy (n = 4) or on clinical grounds (n = 2) were reviewed. In those who had follow-up MRI (n = 2) or comparable CT (n = 3), interval changes of MR findings and comparison with CT images were done. RESULTS: Swollen kidney with dark signal intensity rim involving the inner cortex and column of Bertin was noted on T2-and T1-weighted images. It was more conspicuous on T2-weighted images. The lesion did not enhance and was differentiated from uninvolved renal parenchyma. In the follow-up MRI, thickened dark signal intensity was more prominent and proved to be calcification or fibrosis. CONCLUSION: MRI, especially T2-weighted and contrast-enhanced T1-weighted imaging, was helpful in evaluating renal cortical necrosis.     

Magnetic resonance imaging of pyomyositis in 43 cases

PURPOSE: To describe the magnetic resonance imaging (MRI) findings in pyomyositis. METHODS AND MATERIALS: Forty-three patients with proven muscle infection (30 males, 13 females) ranging in age from 14 to 86 years (mean 42 years) were studied with MRI. The initial clinical diagnose were soft tissue infection (n=27), neoplasm (n=12), thrombophlebitis (n=3), and lymphedema (n=1). Spin-echo T1- and T2-weighted images were obtained in all cases and STIR sequence in 6. Spin-echo T1-weighted images after Gd-DTPA injection were obtained in 16 cases. The signal intensity findings, the extent of the abnormalities in the soft tissue (muscle, fascial and subcutaneous involvement), the presence of fluid collections, and the involvement of neighbouring bone and joint were reviewed retrospectively. RESULTS: A hyperintense signal on T2-weighted and STIR images were detected in all patients. Fluid collections were seen in 21 cases as localized areas of hypointensity on the T1-weighted images, and highly hyperintense areas on the T2-weighted images. In four patients a rim of high signal intensity was seen around the fluid collection on the T1-weighted images. On contrast-enhanced T1-weighted images there was diffuse enhancement in the patients without fluid collections that was heterogeneous in seven and homogeneous in two. After Gd-DTPA all fluid collections showed a central area without enhancement and a well-defined enhancing peripheral rim. Involvement of adjacent structures included subcutaneous tissue (n=25), bone marrow (n=14), fascial planes (n=15) and joints (n=11). CONCLUSION: MRI is useful in the assessment of pyomyositis and in determining the location and extension. A hyperintense rim on unenhanced T1-weighted images and peripheral enhancement after Gd-DTPA are useful for identifying the number, size, and location of soft-tissue abscesses.     

Chondroblastoma and clear cell chondrosarcoma: radiological and MRI characteristics with histopathological correlation

OBJECTIVE: To analyze and compare the radiological and magnetic resonance imaging (MRI) appearances of chondroblastoma and clear cell chondrosarcoma with histopathological correlation. DESIGN AND PATIENTS: Twelve patients with histologically proven chondroblastoma and of another four patients with clear cell chondrosarcoma were investigated by radiographs and MRI (T1-, T2-weighted sequences, intravenous gadolinium application). Additionally, the clinical and radiologic data of seven cases of clear cell chondrosarcoma without available MRI were considered. The localization, calcification of tumor matrix, periosteal reaction, cortical bone and patterns of bone destruction were analyzed according to the Lodwick radiological grading system (LRGS). The signal intensity on T1- and T2-weighted sequences, characteristics of contrast enhancement, associated bone marrow edema, soft tissue reaction and joint involvement were evaluated. Histopathological specimens were available in all cases. RESULTS: The age of patients with chondroblastoma (range 15-59 years, mean 22.3 years) was lower than that of those with clear cell chondrosarcoma (range 19-61 years, mean 36.6 years), and the lesions were smaller in the chondroblastoma group (range 1-4 cm, mean 2.3 cm) than in patients with clear cell chondrosarcoma (range 3-7.5 cm, mean 5.2 cm). The chondroblastomas were more confined to the epiphysis (10/12) than the clear cell chondrosarcomas. All chondroblastomas and clear cell chondrosarcomas except one were classified as grade 1A or 1B according to the LRGS; one clear cell chondrosarcoma was judged as grade 2. Signal intensity of the tumors on MRI was very heterogeneous in both groups. High signal intensity on T2-weighted MR images in chondroblastoma mostly corresponded to areas with aneurysmal bone cyst components and in clear cell chondrosarcoma to islands of hyaline cartilage. Contrast enhancement occurred in all tumors and tended to be more intense with clear cell chondrosarcoma. Chondroblastoma was more frequently associated with bone marrow edema (11/12), periosteal reaction (10/12), soft tissue reaction (7/12) and synovitis (3/12). CONCLUSION: Chondroblastoma occurs in younger patients, is smaller than clear cell chondrosarcoma and is more confined to the epiphysis. The overlap of signal intensity and contrast enhancement patterns does not allow a reliable differentiation of the two tumors by MRI. Chondroblastomas are typically associated with bone marrow edema, periosteal reaction and soft tissue reaction.     

儿童戈谢病骨骼影像特征分析

目的 探讨儿童戈谢病骨骼病变的X线平片及MRI表现特点.方法 109例戈谢病患儿均行常规脊柱正、侧位及双股骨正位X线检查,同时行骨盆止位检查18例,左腕正位检查14例;14例患儿同时行股骨MR平扫.MR扫描序列为标准T1WI、T2WI、T2压脂像冠状面及矢状而扫描.综合分析其影像特点.结果 骨骼异常X线征象包括:长骨干骺端烧瓶样畸形89例(81.7%)、骨质稀疏91例(83.5%)、长骨十骺端密度不同程度的减低86例(78.9%)、骨皮质变薄69例(63.3%)、溶骨性破坏31例(28.4%)、骨硬化12例(11.0%)、骨囊性病变16例(14.7%),病理性骨折26例(23.9%),其中椎体压缩性骨折24处、股骨颈陈旧性骨折5处、脊柱弧形后凸3例、股骨头碎裂变形4例、髋关节脱位4例.,14例股骨MRI显示,T1WI及T2WI骨髓内均可见异常信号,分别表现为T1WI、T2WI信号减低4例;在T2WI及压脂像信号广泛减低的基础上出现限局性高信号或混杂信号10例.结论 儿童戈谢病骨骼病变的影像表现有一定特征性,对临床诊治及观察疗效具有较大的帮助.

Abstract：

Objective To discuss the imaging features of skeletal changes in children with Gaucher disease on X-ray and MRI images.Methods One hundred and nine children with Gaucher disease were enrolled in this study.They all received routine X-ray for spine with anterior-posterior(A-P)and lateral view and bilateral femurs with A-P view.Among them.18 patients received X-ray for pelvic with A-P view.14 patients received X-ray for left wrist with A-P view.and 14 patients received MRI scan for femur.The MRI scan included T1-weighted imaging,T2-weighted imaging and fat-suppressed T2-weighted imaging with short tau inversion recovery(STIR)sequence.The imaging features of the X-ray and MRI images were analyzed retrospectively.Results The most common feature is osteoporosis,which presented in 91 cases (83.5%).Besides this,decreased density of metaphysis occurred in 86 cases(78.9%).erlenmeyer flask deformity of metaphysis occurred in 89 patients(81.7%),thinner cortex occurred in 69 cases(63.3%),osteolytic destruction occurred in 31 cases(28.4%).pathological fractures occurred in 26 cases (23.9%),osteosclerosis occurred in 12 cases(11.0%).cystic degeneration of bone occurred in 16 cases (14.7%),and dislocation of the hip occurred in 4 cases.All 14 patients received MRI presented abnormal signals.Among them,4 patients presented low signal intensity both on T1-weighted and T2-weighted images in bone marrow;the other ten presented high signal intensity mixed in low signal intensity areas on T2-weighted and fat-suppressed T2-weighted images.Conclusions The imaging features of skeletal changes in children with Gaucher disease are of some characteristics,which could provide useful information for the clinical treatment.     

滑膜血管瘤的影像学诊断

目的:分析滑膜血管瘤的影像学表现及诊断价值。材料和方法:回顾性分析已确诊12例滑膜血管瘤(男性7例,女性5例),其中膝关节5例、肘关节2例、腕关节2例、髋关节2例、肩关节1例。X线检查8例,CT检查平扫2例,MRI检查5例其中增强4例,血管造影1例。结果:X线平片可以出现静脉石、软组织肿胀、骨质侵蚀、继发骨关节炎表现。CT表现为软组织肿胀及骨质侵蚀,血管造影仅发现膝周少许异常染色血管影。MRI发现局限型(2例)和弥漫型(3例),局限型表现为髌上囊区局限肿块影,T1WI上等低信号影,于T2WI序列表现为高信号;弥漫型2例表现为弥漫性生长可突破关节囊,病灶大部分呈T1WI上等低信号影,T2WI上高信号影,其内含有更低信号细条索影及高信号分隔影。1例含有大量含铁血黄素则T1WI及T2WI上均表现为低信号。结论:X线平片、CT及血管造影对滑膜血管瘤诊断有一定帮助,MRI可明确显示血管瘤特征性脉管及纤维脂肪成分,提高该病术前诊断率。     

Colorectal mucinous carcinoma: findings on MRI

PURPOSE: The purpose of this work was to define the characteristic MR features of colorectal mucinous carcinomas and to correlate the mucin pool with the signal intensity of this tumor. METHOD: MRI of 12 cases of pathologically proven colorectal carcinoma containing mucin was evaluated. We analyzed the signal intensity of tumor on T1- and T2-weighted MR images and correlated the area of intratumoral high signal intensity on T2-weighted images with the mucinous pool on the pathologic specimens. Two radiologists independently estimated the area of high signal intensity in the tumor on T2-weighted images and one pathologist estimated the amount of mucinous pool in the pathologic specimen. RESULTS: In 9 (75%) of 12 cases, focal or diffuse high signal intensity areas were detected on T2-weighted fast spin echo images. In seven cases in which mucin pools were seen macroscopically, partial (n = 3) or diffuse high signal intensity areas were noted on the T2-weighted images. Among the five cases in which microscopic mucinous pools were detected on the pathologic slides, three cases showed no high signal foci on MR images, and in the remaining two cases, high signal intensity areas were noted as small foci. CONCLUSION: Intratumoral high signal intensity on T2-weighted fast spin echo MR images occurs in mucinous carcinomas and correlates with the mucin pools on pathologic specimens.     

Solitary fibrous tumor of the pleura: MR appearance and enhancement pattern

PURPOSE: The aim of the current study was to characterize the MR appearance of solitary fibrous tumor of the pleura (SFTP). METHOD: Twenty-two consecutive patients with histologically confirmed SFTP were retrospectively evaluated with MRI. RESULTS: Tumors demonstrated low signal intensity (n = 18, 82%), iso signal intensity (n = 2, 9%), and high signal intensity (n = 2, 9%) on T1-weighted images. On T2-weighted images, tumors were observed as low signal intensity (n = 10, 45%), high signal intensity (n = 2, 9%), and mixed signal intensity (n = 10, 45%). Solid component in the proliferation of tumor cells corresponded to low signal intensity in 12 tumors (55%) on T2-weighted images. On gadolinium-enhanced T1-weighted images, inhomogeneous enhancement (n = 18, 82%), nodular enhancement (n = 6, 27%), and homogeneous enhancement (n = 4, 18%) were observed. The enhanced lesion within the tumors had dense tumor tissue and dilated microvessels in the pathologic specimen. CONCLUSION: SFTP shows variable appearance and enhancement pattern on MRI according to morphologic tumor heterogeneity.     

MRI of musculoskeletal extraspinal tuberculosis

PURPOSE: The aim of this study was to describe the MR findings in extraspinal musculoskeletal tuberculosis (EMT). METHOD: A retrospective review was conducted of the MR findings of 18 patients with microbiologically and/or pathologically proven EMT. All MR studies were performed using T1-and T2-weighted spin echo sequences. T1-weighted spin echo sequences after Gd-DTPA injection were obtained for 12 patients. The MR images were evaluated for abnormalities in joints, bones, and soft tissues, and the results were grouped by anatomic localization, frequency distribution of structures affected, and morphologic patterns of involvement. RESULTS: Isolated soft tissue tuberculosis was found in 10 (55.5%) patients and involvement of more than one structure in 8 (44.4%). Pyomyositis (n = 6) and arthritis with involvement of adjacent soft tissues (n = 7) were the most common forms of presentation. One patient presented with isolated fascial superficial tissue involvement in one leg. Isolated pyomyositis involving one (n = 3) or two (n = 3) muscles was homogeneous in six cases and showed intermediate (n = 6), low (n = 2), or high (n = 1) signal intensity on T1-weighted images and a high and very hyperintense signal on T2-weighted images. The tenosynovitis synovial fluid was homogeneous (n = 1) or heterogeneous with multiple tiny hypointense nodules (n = 1) on T2-weighted images. The subdeltoid bursitis fluid was characterized by homogeneous low signal intensity with a hyperintense rim (n = 2) on T1-weighted images and homogeneous (n = 1) or heterogeneous hyperintense signals with areas of low signal intensity (n = 1) on T2-weighted images. In tuberculous arthritis, the synovial joint fluid (n = 7) showed heterogeneous (n = 4) or homogeneous (n = 3) low signal intensity on T1-weighted images and high or very high signal intensity on T2-weighted images. Where involved, the adjacent muscle(s) (n = 8) were usually hypointense on T1-weighted images and very hyperintense on T2-weighted images. Associated cellulitis was found in arthritis with involvement of neighboring soft tissues (n = 5), pyomyositis (n = 2), and tenosynovitis (n = 1). The images obtained after Gd-DTPA showed peripheral (n = 10) or heterogeneous (n = 1) enhancement or no enhancement (n = 1). CONCLUSION: The MR findings for EMT are variable. Although diagnosis is dependent largely on prior presumption and clinical context, MRI provides valuable guidelines in defining the extent of the lesions to select the appropriate treatment and for follow-up of abnormalities.     

中毒性脑病的CT与MRI表现

目的:分析各种中毒性脑病的CT与MRI表现.材料和方法:分析23例中毒性脑病患者的CT和MRI表现,其中7例海洛因烫吸中毒,8例CO中毒,2例工业有机溶剂中毒,6例代谢性中毒,总结其CT和MRI的诊断要点.结果:CT表现为脑白质及神经核团的对称性低密度,MRI表现为相应的长T1、长T2信号.其中基底节区发生改变的有19例,小脑齿状核的有5例,脑干有3例,丘脑有6例,发生广泛白质改变的有10例.小脑齿状核发生改变的仅限于海洛因烫吸中毒患者.结论:CT和MRI能发现脑白质及神经核团的变性和坏死改变,但各种中毒性脑病的这些改变大都不具有特异性,只是小脑齿状核的改变仅见于海洛因烫吸中毒患者.正确的诊断需认真分析影像表现,密切结合临床病史.     

Chondrosarcoma: MR imaging with pathologic correlation.

Magnetic resonance (MR) images of 21 surgically confirmed chondrosarcomas were retrospectively reviewed in conjunction with plain radiographs and computed tomographic scans and correlated with pathologic findings. The tumors appeared lobulated, and signal intensity, as analyzed visually (intermediate on T1-weighted, high on T2-weighted images), was similar for all lesions, regardless of pathologic type. Size of lesion was not an indicator of grade. The appearances of mesenchymal and dedifferentiated chondrosarcomas mimicked that of conventional chondrosarcoma. Extraskeletal chondrosarcoma was visualized as a lobulated soft-tissue mass. In all cases, MR imaging accurately depicted intraosseous and soft-tissue extent of tumor noted at surgery and pathologic examination. Histologic type or grade of chondrosarcoma generally cannot be characterized on the basis of visual analysis of signal intensity noted on routine MR images. However, MR imaging is excellent for exact delineation of tumor extent.     

Shoulder MRI after surgical treatment of instability.

OBJECTIVE: To analyze magnetic resonance imaging (MRI) findings of the shoulder after an instability operation. MATERIALS AND METHODS: Physical examinations, radiographs and MRI of 10 patients after anterior glenoid bone block insertion for ventral instability were compared. MRI included T1-weighted spin-echo (TR = 600, TE = 20 ms) and T2*-weighted gradient-echo sequences (TE = 600, TE = 18, Flip = 30 degrees) in the axial, oblique-coronal and oblique-sagittal planes. RESULTS: No patient suffered from recurrent subluxation. We found fusion of the bone block with the anterior glenoid in seven cases, dislocation of the bone block without contact to the glenoid in one case, and no visible bone block in two cases. On MRI, the bone block showed either signal intensity equivalent to fatty bone marrow (n = 4) or was devoid of signal consistent with cortical bone or bone sclerosis (n = 4). In all patients, a low signal intensity mass, 2-4 cm in diameter, was visible next to the glenoid insertion site. CONCLUSION: Insertion of a bone block onto the anterior glenoid induces formation of scar tissue, increasing the stability of the shoulder joint. This scar is well visible on MRI and forms independently of the behavior of the bone block itself. MRI is ideally suited for evaluating postoperative shoulder joints after bone-grafting procedures.     

颅底骨源性肿瘤的MRI影像诊断

目的：分析颅底骨源性肿瘤的ＭＲＩ表现并与ＣＴ和病因对照，研究ＭＲ在诊断中的价值与限度。材料与方法：搜集了经手术病理证实的颅底骨源性肿瘤２２例（软骨肉瘤３例，软骨瘤２例，转移瘤２例，脊索瘤１０例，骨巨细胞瘤２例，恶性纤维组织瘤１例，骨化性纤维瘤２例），全部行ＭＲ检查（１１例行增强检查），８例行ＣＴ检查。结果：绝大部分肿瘤均有一清晰的边缘，Ｔ１Ｗ上呈低或等信号，Ｔ２Ｗ上呈不均匀高信号，Ｔ１Ｗ上呈低信号     

结直肠癌的MRI初步研究

目的 探讨MRI对结直肠癌检查的可行性及其价值。方法 对38例经临床拟诊为结直肠癌患者行MR检查,检查前经直肠灌水300—1000ml。分别行轴面平扫,轴面、矢状面和冠状面3个平面增强扫描及水成像。结果 38例中经手术病理证实的结直肠癌31例,5例表现为腔内局限性软组织肿块,26例表现为肠壁不规则增厚,肠腔环形狭窄环绕肠腔1周或部分,平扫T1WI上呈等信号,T2WI上30例呈略高信号,1例呈明显高信号;钆喷替酸葡甲胺(Gd—DTPA)增强扫描病灶均明显强化。5例平扫SE序列T1WI上病灶周围脂肪间隙内见斑片状低信号。增强后病变段肠壁外缘光滑12例,不光滑或有结节影向外突出19例。结直肠水成像满意的24例中显示为病变部位肠腔内不规则充盈缺损14例,10例病变远侧端呈“袖口征”及“截断征”,近侧端未显示。MRI可以正确识别31例经病理证实的结直肠癌中的30例和7例非结直肠癌中的4例,诊断的敏感度、特异度和准确度分别为96．8％、57．1％和89．5%。MRI对结直肠癌T分期的准确度为83．9％(26／31),其中对T1～2期为75．0％(9／12)、对13期为88．2％(15／17)、对T4期为100％(2／2)。结论 MRI可以从整体上显示结直肠癌的纵向和横向侵犯,可以较准确地判断肿瘤在肠壁的浸润深度,水成像最大信号强度投影(MIP)重建可部分替代钡灌肠检查,为制定临床治疗方案提供有益的指导。     

Radiologic assessment of metastases to the thyroid gland

PURPOSE: We reviewed the radiologic and clinical data in patients with metastatic disease to the thyroid gland and assessed the role of radiologic techniques in this disorder. METHOD: The findings on US (n = 11), CT (n = 7), MRI (n = 6), palpation or US-guided fine needle aspiration (FNA) biopsy, and clinical records were reviewed in 11 cases of pathologically verified metastatic tumors of the thyroid gland. RESULTS: Five patients had palpable thyroid nodules and six had nonpalpable nodules discovered incidentally with imaging procedures. Three patients had no known malignancies at the time of diagnosis of thyroid tumors. Correct diagnosis was obtained in 10 of the 11 cases with FNA biopsy. Thyroid metastases were detected in all of the cases with US and MRI and six of the seven cases with CT. Thyroid metastases were solitary (n = 5) or multiple (n = 6), and about half of them measured <2 cm in diameter. These tumors typically had well defined margins and no calcification and sometimes had cystic portions. Multiple nodules within the same patient were radiologically quite similar to each other. On US, metastases appeared as hypoechoic or markedly hypoechoic areas without halo, on CT as low density areas, and on MRI as areas of varying signal intensities. Half of the metastases showed hypointensity on either T2-weighted images or gadolinium-enhanced T1-weighted images. The tumors involved lymph nodes in 10 cases and other remote organs in 5. Level I or II or parotid nodes were involved in six cases. CONCLUSION: These radiologic features may alert clinicians to a possibility of metastatic thyroid cancer. US combined with US-guided FNA biopsy is suitable for early diagnosis of metastases to the thyroid gland.     

颅底骨源性肿瘤的CT、MRI影像诊断

目的：分析颅底骨源性肿瘤的 Ｃ Ｔ 、 Ｍ Ｒ Ｉ 表现并与病理对照,探讨 Ｃ Ｔ 和 Ｍ Ｒ Ｉ 对该类疾病的诊断价值与限度。方法： 收集了经手术和病理证实的颅底骨源性肿瘤２３ 例（ 软骨肉瘤５ 例、软骨瘤２ 例、转移瘤３ 例、脊索瘤８ 例、骨巨细胞瘤２ 例、动脉瘤样骨囊肿１ 例、骨化性纤维瘤２ 例） ,全部病例均行 Ｃ Ｔ 和 Ｍ Ｒ Ｉ 检查（ 其中１１ 例行增强 Ｍ Ｒ Ｉ 检查,７ 例行增强 Ｃ Ｔ 检查） 。结果：大部分肿瘤边界清晰, Ｍ Ｒ Ｉ Ｔ１ Ｗ Ｉ 呈低或等信号, Ｔ２ Ｗ Ｉ 呈不均匀高信号,且 Ｔ１ Ｗ Ｉ 低信号区在 Ｔ２ Ｗ Ｉ 上随回波时间延长信号仍呈低信号而提示钙化。 Ｃ Ｔ 上显示不同程度骨质破坏及钙化。 Ｍ Ｒ Ｉ 显示斜坡、岩骨破坏较敏感。结论： Ｃ Ｔ 能准确显示骨质破坏情况及钙化程度, Ｍ Ｒ Ｉ 在显示病变的范围方面要优于 Ｃ Ｔ ,两者相结合是诊断颅底骨源性肿瘤的最佳影像学检查方法。     

MRI diagnosis and follow-up of subcutaneous fat necrosis

The purpose of this report is to present the MRI features of subcutaneous fat necrosis (SFN) and the natural history of this process. We have seen 12 patients with SFN, one case of which was confirmed histopathologically. In six patients, a follow-up MRI study was performed. MRI findings were very similar in all of the cases: small, linear, and spiculated lesions with one or two components: a globular area yielding high signal intensity on T1-weighted images, intermediate to high signal intensity on fast SE T2-weighted images and focal signal void on short-inversion -time inversion recovery (STIR) sequence, corresponding to an area of fat necrosis; and a laminar starred component, with low signal intensity on T1 and fast SE T2-weighted images and high signal intensity on the STIR sequence, corresponding to reactive fibrous tissue. The follow-up MRI study of six patients showed either disappearance (n = 2) or decrease in size (n = 3) of the globular component; in one patient, no change was observed. A less prominent decrease of the laminar component also was seen in five patients. One patient did not present any change in this laminar component. The most characteristic MRI findings of this lesion are the high signal intensity areas on T1-weighted images, their small size (<3 cm), their linear spiculated shape with both laminar and globular components, and no contrast enhancement after injection of gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) injection. We believe that the location, size, morphology, and MRI signal intensity of SFN may allow its differentiation from other types of soft tissue lesions.     

Detection of myocardial involvement in patients with sarcoidosis applying T2-weighted,contrast-enhanced,and cine magnetic resonance imaging: initial results of a prospective study

PURPOSE: To assess myocardial magnetic resonance imaging (MRI) findings in sarcoidosis. METHODS: Cardiac assessment was prospectively performed in patients with sarcoidosis and included physical examination, electrocardiogram, echocardiography, thallium-201 myocardial scintigraphy, and coronary angiography if coronary disease was suspected. T2-weighted black-blood single-shot and inversion recovery fast spin echo, functional gradient echo, and T1-weighted gadolinium-DTPA-enhanced cardiac MRI examinations were performed in 40 patients while other cardiac disease was excluded. RESULTS: Results of the MRI images were normal in cardiac-asymptomatic stage I or Lofgren syndrome patients (n = 4). Among the patients with cardiac-asymptomatic multiple organ sarcoidosis, 17 of 31 patients (54%) had MRI myocardial abnormalities similar to those observed in five patients with cardiac symptoms: nodular peripheral increased intramyocardial signal intensity on both T2-weighted and contrast-enhanced images (n = 5), focal or patchy increased signal on contrast-enhanced images with or without myocardial thickening (n = 10), and focal increased signal only on T2-weighted images with or without myocardial thinning (n = 2). Focal contractility abnormalities were noticed in nine patients. CONCLUSIONS: These preliminary results emphasize the occurrence of subclinical myocardial MRI abnormalities in patients with ongoing systemic sarcoidosis.