3.0T MR骶神经成像在神经源性膀胱病因探究中的价值

目的:探讨3.0T MR腰骶丛神经成像在探究神经源性膀胱(NB)病因中的价值.方法:回顾性分析119例NB患者的临床和影像资料.结果:影像诊断包括神经根肿瘤69例,骶神经多发异常T2 WI高信号28例,脊髓栓系18例,隐性脊柱裂14例,骶尾部软组织包块3例,神经节细胞瘤2例,神经纤维瘤病1例,骶椎转移瘤1例,骶神经无异常27例.骶神经占位最常发生于S2神经根(62根),其次为S1(41根)、S3(28根)、S4-S5(24根);病变直径≥15 mm者34枚,10～14 mm者36枚,5～10 mm者37枚,≤5 mm者61枚.神经根占位MRI表现为椭圆形T2 WI高信号,T1 WI等信号;脊髓栓系MRI可见骶管内脂肪瘤、圆锥低位和马尾牵拉.骶尾部成熟畸胎瘤表现为T1WI、T2 WI混杂高、低信号;神经节细胞瘤多呈T1 WI低信号、T2 WI高信号.神经纤维瘤病表现为位于脊柱旁的T1WI等信号、T2 WI稍高信号;隐形脊柱裂表现为椎管畸形、棘突及椎板缺损.结论:MRI能准确、直观显示骶丛神经的特征及病灶的数量、位置,有助于NB的诊断、鉴别诊断及规范化治疗.     

Imaging in chronic achilles tendinopathy: a comparison of ultrasonography,magnetic resonance imaging and surgical findings in 27 histologically verified cases

 Objective. To compare information gained by ultrasonography and magnetic resonance imaging (MRI) in chronic achilles tendinopathy with regard to the nature and severity of the lesion. Design. Imaging of both achilles tendons with ultrasonography and MRI was performed prior to unilateral surgery. Operative findings and histological biopsies together served as a reference. Patients. Twenty-seven patients (22 men, 5 women; mean age 44 years; 21 athletes) suffering from chronic achilles tendinopathy participated in the study. Eighteen patients had unilateral and 9 had bilateral symptoms. Results and conclusions. Surgical findings included 4 partial ruptures, 21 degenerative lesions and 2 macroscopically normal cases. Microscopy revealed tendinosis (degeneration) in all tendon biopsies, including cases with a partial rupture, but only slight changes in the paratendinous tissues (paratenon). Ultrasonography was positive in 21 of 26 and MRI in 26 of 27 cases. Severe intratendinous abnormalities and a sagittal tendon diameter >10 mm suggested a partial rupture. In tendons with a false negative result histopathological changes were mild and a tendency towards a better clinical outcome was noted in the sonographic cases. Assessment of the paratenon was unreliable with both methods. Ultrasonography and MRI give similar information and may have their greatest potential as prognostic instruments.     

原发性骶骨肿瘤病理及影像学表现

目的:分析原发性骶骨肿瘤的病理学分型及影像学表现特点。方法:48例原发性骶骨肿瘤均经手术病理证实,术前均行常规X线平片、CT和/或MR检查,结合病理回顾分析了其影像学表现。结果:原发性骶骨肿瘤以脊索瘤(21例)最多见,其次是巨细胞瘤(7例)、神经源性肿瘤(6例)、软骨肉瘤(4例)、滑膜肉瘤(3例),囊肿(3例),其它相对少见,包括纤维组织细胞癌1例,尤文氏肉瘤1例,梭形细胞癌1例,节细胞神经瘤1例。影像表现包括软组织肿块、骶孔扩大、瘤灶内钙化、骨嵴形成等不同特点。常见原发骶骨肿瘤常有其特征性影像学表现。结论:原发骶骨肿瘤病理分型相对复杂,影像表现多样化,诊断常需综合不同影像检查手段。     

Gd-DTPA enhanced MR imaging in intracranial tuberculosis

Summary Twenty-six patients with intracranial tuberculosis (Tb) (10 with acute meningitis, 5 with chronic meningitis, 5 with meningitic sequelae and 6 with localized tuberculoma(s) were examined with MR before and after Gd-DTPA enhancement (0.1 mmol/kg), using 2.0T superconducting unit, and the images were retrospectively analyzed and compared with CT scans. Without Gd-DTPA enhancement, the MR images were generally insensitive to detection of active meningeal inflammation and granulomas. The signal intensity of granulomas was usually isointense to gray matter on both T1- and T2-weighted images, whether they were associated with diffuse meningitis or presented as localized tuberculoma(s). A few granulomas showed focal hypointensity on T2-weighted images. Calcifications seen on CT of the meningitic sequelae group usually appeared markedly hypointense on all spin-echo sequences. On Gd-DTPA enhanced T1-weighted images, abnormal meningeal enhancement indicating active inflammation was conspicuous, and the granulomas often appeared as conglomerated ring-enhancing nodules, which seems to be characteristic of granulomas. Thin rim enhancement around the suprasellar calcifications were observed in two out of 5 patients with meningitic sequelae. Compared with CT, MR detected a few more ischemic infarcts, hemorrhagic infarcts, meningeal enhancement and granulomas in the acute meningitis group, but missed small calcifications in the basal cisterns well shown on CT in the sequelae group. Otherwise, MR generally matched CT scans. MR imaging appears to be superior to CT in evaluation of active intracranial Tb only if Gd-DTPA is used, while CT is better than MR in evaluating meningitic sequelae with calcification.     

Postradiation sarcomas of the pelvis after treatment for uterine cervical cancer: review of the CT and MR findings of five cases

Objective. To characterize the radiologic features of postradiation sarcomas arising in the pelvic bones following treatment for uterine cervical carcinoma. Design and patients. Five patients who developed postradiation sarcomas in the pelvic bones following radiation therapy for carcinoma of the uterine cervix within the irradiated field were evaluated. Pelvic radiographs, computed tomography (CT) and magnetic resonance (MR) imaging were undertaken in all patients. Histologic confirmation of the tumor type was obtained. Results. Three patients whose tumors were characterized as an osteosarcoma, an angiosarcoma and a malignant fibrous histiocytoma (MFH) showed a large round or oval mass mainly in the sacroiliac joint which extended into the posterior gluteal soft tissues. In a fourth patient an osteosarcoma developed in the central ilium extending widely into the soft tissues both anteriorly and posteriorly, with calcified areas within the extraosseous mass. The fifth patient had a MFH which showed osteolytic destruction of the cortex of the acetabulum, and minimal soft tissue extension. There were no specific features or signal intensity changes on MR imaging to differentiate these cases from primary sarcomas. Conclusion. Postradiation sarcoma must be considered in patients with uterine carcinoma when a soft tissue mass is seen in the previously irradiated field, especially if the mass is posterior to the sacroiliac joint and the latent period is more than 5 years. Received: 3 May 2000 Revision requested: 14 July 2000 Revision received: 28 July 2000 Accepted: 20 November 2000     

MRI diagnosis of diabetic muscle infarction: report of two cases

 Diabetic muscle infarction (DMI) is a rare complication of diabetes mellitus occurring in patients with poorly controlled insulin-dependent diabetes. In previous reports, the diagnosis of this condition was based on the pathologic studies, although MRI examinations were performed in a few patients as part of the diagnostic work-up. In this report, we describe two additional cases of DMI where the diagnosis was based on the MRI findings in conjunction with the clinical picture and laboratory studies. The patients usually present with thigh or calf pain and swelling, are afebrile, and have normal white blood cell count. MRI examination typically shows diffuse swelling and increased signal intensity on T2-weighted images in the affected muscles, with no focal fluid collections. In the proper clinical setting, these findings are diagnostic of DMI and patients should be spared unnecessary invasive diagnostic examinations such as lower extremity venograms and biopsies.     

肾结核的MRI表现(附12例分析)

目的:分析肾结核的影像学特征。方法:搜集2002年6月~2004年9月12例行MR检查诊断为肾结核的病例资料,均行平扫T1WI和T2WI,其中行增强扫描8例,8例行磁共振尿路成像检查。结果:肾结核的主要表现为肾皮质变薄,肾实质内脓腔或脓肿形成并围绕肾盏排列,肾盂扩张与肾盏扩张不成比例,壁增厚;增强扫描出现空洞壁和破坏肾盂、肾盏的点、线状强化。结论:MRI是诊断肾结核良好的影像学方法。     

Central nervous system tuberculosis: MRI

The MRI findings of 18 proven cases of central nervous system (CNS) tuberculosis were reviewed; 10 patients were seropositive for HIV. All had medical, laboratory, or surgical proof of CNS tuberculosis. Eleven patients had meningitis, of whom two also had arachnoiditis. Five patients had focal intra-axial tuberculomas: four brain masses and one an intramedullary spinal lesion. Two patients had focal extra-axial tuberculomas: one in the pontine cistern, and one in the spine. In all 11 patients with meningitis MRI showed diffuse, thick, meningeal enhancement. All intraparenchymal tuberculomas showed low signal intensity on T2-weighted images and ring or nodular enhancement. The extra-axial tuberculomas had areas isointense or hypoitense relative to normal brain and spinal cord on T2-weighted images. Although tuberculous meningitis cannot be differentiated from other meningitides on the basis of MR findings, intraparenchymal tuberculomas show characteristic T2 shortening, not found in most other space-occupying lesions. In the appropriate clinical setting, tuberculoma should be considered.     

脊柱结核的MRI表现

目的：分析脊柱结核的各种MRI表现以提高诊断准确率。方法：利用MR对36例不同位置的脊柱结核进行成像,对各种MR征象进行回顾性分析。结果：①36例脊柱结核患者中,单椎体受累3例,2个椎体受累15例,2个以上椎体受累18例,椎体破坏呈不均匀长T1、长T2信号;②34例椎间盘不同程度破坏,呈长T1、长T2信号,椎间隙变窄或消失;③23例出现寒性脓肿,呈长T1、长T2为主的混杂信号,增强扫描呈不均匀强化或环形强化,脓肿壁明显强化并可见不规则间隔;④23例脊髓及硬膜囊受压。结论：利用心可对脊柱结核的不同表现进行良好显示,为诊断和指导治疗提供重要信息。     

Complete rupture of the distal semimembranosus tendon with secondary hamstring muscles atrophy: MR findings in two cases

Complete rupture of the hamstring muscles is a rare injury. The proximal musculo-tendinous junction is the most frequent site of rupture. We present two cases of complete rupture of the distal semimenbranosus tendon, which clinically presented as soft-tissue masses. MR imaging permitted the correct diagnosis. There has been only one other such case reported. Received: 15 October 1999 Revision requested: 6 February 2000 Revision received: 8 March 2000 Accepted: 13 March 2000     

Tuberculous tenosynovitis of the wrist: MRI findings in three patients

 We report recent MRI findings in patients with tuberculous tenosynovitis of the wrist. Marked synovial thickening around the flexor tendons and fluid in the tendon sheath were clearly shown on MRI. Post-contrast study was useful in distinguishing the thick tenosynovium from the surrounding structures and fluid in the tendon sheath. The well-enhanced tenosynovium was also seen in the carpal tunnel in all cases. On the basis of these findings, we could easily distinguish tenosynovitis from other soft-tissue-mass lesions, such as tumors or infected ganglia. Tuberculous tenosynovitis is often not diagnosed early, and its differentiation from soft tissue tumors may be clinically difficult. MRI, particularly post-contrast study, is useful for early diagnosis of, and planning treatment for, tuberculous tenosynovitis.     

Silicone synovitis: MR imaging in five patients

 Silicone synovitis is a known complication of silicone implants used in orthopedic surgery for joint reconstruction. It has been studied with routine radiography; however, no report on magnetic resonance imaging abnormalities of this condition exist in the literature. This article reports on five patients with silicone synovitis studied by magnetic resonance imaging. All patients showed hypointense implants that were deformed, fragmented or subluxed, and intra- and periarticular silicone particles were evident on T1- and T2-weighted images.     

Intramedullary chondroid tumors of bone: correlation of abnormal peritumoral marrow and soft-tissue MRI signal with tumor type

 Objective. To determine whether enchondromas and chondrosarcomas can be differentiated on the basis of peritumoral MR signal abnormality. Design. STIR and T2-weighted MRI images were retrospectively assessed for the presence and extent of abnormal peritumoral marrow and soft-tissue signal. The cause of the peritumoral signal abnormality was determined by histologic correlation with resection specimens. The presence or absence of bone destruction was noted. Patients. Twenty-three patients were studied: ten with enchondromas (three men, seven women; ages 33–73 years) and 13 with chondrosarcomas (seven men, six women; ages 25–88 years). Results. Abnormal peritumoral marrow signal was present on STIR images around none of 10 enchondromas and all of 13 chondrosarcomas (P<0.0001). The marrow signal abnormality corresponded histologically to fine marrow fibrosis in all cases. Adjacent abnormal soft-tissue signal was present on STIR images around none of ten enchondromas and eight (62%) of 13 chondrosarcomas (P=0.0026). Abnormal soft-tissue signal was more common around high-grade than low-grade chondrosarcomas (100% vs 38%, P=0.028), and was more extensive (mean extent 28 mm vs 8 mm; P>0.04). In the subset of tumors without bone destruction, peritumoral marrow signal abnormality was present around none of ten enchondromas and all of five chondrosarcomas (P=0.0003); abnormal soft-tissue signal was present around none of ten enchondromas and two of five chondrosarcomas (P>0.05). Conclusion. Abnormal marrow or soft-tissue signal around a chondroid tumor is suggestive of chondrosarcoma, even in the absence of bone destruction. STIR images are necessary for adequate detection of peritumoral signal abnormalities.     

脑神经节细胞胶质瘤的影像学表现(附2例报告及文献复习)

目的:探讨脑神经节细胞胶质瘤(GG)的影像学表现及临床病理特点,提高对该病的认识.方法:复习文献并回顾性分析两例经手术病理证实的脑GG的临床、影像学表现及病理特征.结果:两例脑GG临床以头痛为主要症状,1例发生于脑室系统,1例位于枕叶;影像学上形态、密度(信号)、强化方式各异;病理学表现为发育不良的神经元与新生的胶质细...     

Imaging of plant-thorn synovitis

We describe a case of plant-thorn synovitis of the elbow resulting from a thorn injury. This caused recurrent pain and swelling of the elbow over a 3-month period. A magnetic resonance imaging examination was initially requested to exclude septic arthritis, and demonstrated a joint effusion, synovitis, and a 2-cm linear opacity embedded in the synovium. Ultrasound was performed prior to surgery to confirm these findings and provide accurate localization of the thorn fragment, later removed at surgery. To our knowledge this is the first example of this condition that has been confirmed by radiological imaging prior to surgery. Received: 12 August 1999 Revision requested: 31 October 1999 Revision received: 1 May 2000 Accepted: 11 May 2000     

An assessment of the effectiveness of magnetic resonance imaging of the shoulder: literature review

Objective. To analyse and compare all papers published to date (August 2000) that quantify the effectiveness, defined as the impact of clinician’s diagnosis or management plans, or patient outcome, of MRI of the shoulder. Design. A computerised search of Index Medicus with a broad search strategy relating to shoulder MRI was performed. Manual assessment of all papers listed was undertaken with classification of each paper depending on whether it addressed questions of (1) technical performance, (2) diagnostic performance or (3) outcome. Results. Four of 265 qualifying papers addressed aspects of effectiveness and these were reviewed. The impact on the clinician’s diagnosis varied widely between papers: the primary diagnosis was altered in 23% to 68% of cases, and the management plans were subsequently changed in 15% to 61% of cases. Only one paper addressed the impact on patient health. Conclusions. The effectiveness of MRI of the shoulder depends on the clinical skills of the referring clinician and prevalence of disease in the study population. This will have implications when the effectiveness of an imaging technique between different institutions is compared, and this in turn will influence any comparisons of cost-effectiveness. Received: 22 October 1999 Revision requested: 31 January 2000 Revision received: 21 August 2000 Accepted: 24 August 2000     

脊椎结核的低场MRI诊断及临床应用

目的：探讨MRI对脊椎结核的诊断及临床应用价值。方法：对51例X线平片诊断或疑似脊椎结核的患者均进行MRI常规T2WI、T1WI及STIR扫描,以及部分病例进行增强扫描,并进行手术病理结果对照。结果：在51例中,43例X线平片诊断为结核（84．3％）,所有病例在MRI均能正确诊断（100％）,病灶区T1硼上多呈低信号,少部分呈混杂信号,T2WI上多呈不均匀较高信号,脓肿灶呈T1WI低、T2WI高信号。结论：MRI能准确显示病灶的大小和侵犯的范围,尤其是在椎旁寒性脓疡的显示准确性明显优于CT和X线,我们认为MRI对脊椎结核的诊断准确性高,且能早期诊断,应作该病治疗前的常规检查。     

Fat replacement of Hodgkin disease of bone marrow after chemotherapy: report of three cases

 Three cases are presented with fat replacement of Hodgkin disease of bone marrow after chemotherapy. Magnetic resonance imaging on admission demonstrated low-signal intensity of lesions on T1-weighted images and high-signal intensity on short inversion time inversion-recovery images. Seven lesions were observed, five of which were located in the spine and two in the pelvis. All lesions showed reversal of signal intensities after completion of chemotherapy. T1-weighted fat saturation images confirmed the fatty nature of the lesions after treatment. All patients had a nodular sclerosis, Hodgkin disease, type 2. One can speculate as to whether the conversion to fat actually represents a particularly successful result of chemotherapy.     

脊椎结核的MRI诊断价值与脊椎转移瘤对照研究

目的探讨MRI对脊椎结核的诊断价值。材料与方法对13例脊椎结核行矢状位T1WI、T2WI、DWI、FAST准T2WI及轴位T1WI成像;7例行Gd-DTPA增强。随机抽取30例脊椎转移瘤作对照组。观察两组病变椎体、终板、椎间盘和周围软组织的信号变化和增强后改变。结果(1)MRI对鉴别椎体骨炎和转移瘤性椎体骨浸润价值较大;(2)骨内与椎旁冷脓肿形成及椎间盘改变是脊柱结核的典型删表现;(3)Gd-DTPA增强可清楚显示冷脓肿周围纤维肉芽组织及椎管内侵犯;(4)终板破坏常见于脊椎结核。结论MRI对脊椎结核与脊椎转移瘤有较大鉴别诊断价值,对早期和不典型脊椎结核的诊断亦有较大价值。     

Slipped capital femoral epiphysis: a physeal lesion diagnosed by MRI, with radiographic and CT correlation

Objective. To define and compare early lesions associated with slipped capital femoral epiphysis (SCFE) on magnetic resonance imaging (MRI), computed tomography (CT) and radiography. Design and patients. Thirteen patients with 15 symptomatic hips due to SCFE underwent radiography and MRI; CT was performed in 12 patients. SCFE was graded on radiographs, head/neck angles and qualitative changes were evaluated on CT, and morphologic/signal abnormalities were determined on MRI. Results. Physeal widening, apparent on T1-weighted MRI, was evident in every case of SCFE, including one presumed “pre-slip.” T2-weighted images demonstrated synovitis and marrow edema but obscured physeal abnormalities. CT head/neck angles ranged from 4–57° for symptomatic to 0–14° for asymptomatic hips. Physeal and metaphyseal changes were variably identified on both radiographs and CT in all cases of SCFE, but not in the pre-slip. Conclusion. MRI clearly delineates physeal changes of both pre-slip and SCFE, and demonstrates very early changes at a time when radiographs and CT may appear normal.