类风湿性关节炎腕关节病变的影像学分析:X线、CT和MR影像对比观察

目的　比较观察X线平片、CT和MRI在检查类风湿性关节炎 (RA)患者早期腕关节病变中的作用。方法　选取 2 5例RA患者 ,其中女 2 0例 ,男 5例 ,年龄为 2 8～ 70岁 ,平均 4 5 .36岁。临床诊断符合 1987年美国纽约类风湿协会修订的RA诊断标准。为比较观察X线平片、CT和MRI在RA早期诊断中的作用 ,左、右腕分别行CT和MR冠状面扫描。MR成像仪的场强为 0 .3T。扫描时先行平扫 ,扫描序列分别为SET1WI和梯度回波重T2 WI(T2 WI)。然后行增强T1WI作进一步检查。结果　 2 5例临床诊断为RA患者的 5 0个腕关节中 ,X线显示骨侵蚀病变者有 14个腕关节 ,MRI检出骨侵蚀病变者有 5 0个腕关节 ;2 5例中行CT检查者有 16例 32个腕关节 ,其中 2 2个腕关节有骨侵蚀病变。MRI共检出 16 4处腕骨的骨侵蚀病灶 ,而X线平片仅检出 2 1处腕骨骨侵蚀病灶 ,CT检出 6 8处骨侵蚀病灶。月骨是最易受累的部位 ,其X线、CT和MR的检出率分别为 6 .0 %、2 8.1%和5 4 .0 %。在类风湿关节炎骨质侵蚀病变的检出上 ,3种检查方法之间经两两比较分析 ,差异均有非常显著性意义 (P值均 <0 .0 1)。MRI不仅可显示RA早期CT和X线所不能显示的腕部骨质侵蚀改变 ,还可显示滑膜炎性及水肿改变 ,增强MRI可鉴别血管翳与关节积液。结论　在检查RA患者早期腕关节病变方     

小儿成神经细胞瘤骨转移影像学特征及诊断价值

目的:分析小儿成神经细胞瘤骨转移的影像学特征,并探讨X线平片、CT和MRI的诊断价值.方法:收集小儿成神经细胞瘤骨转移患者47例,分析骨转移在X线平片、CT和MRI上的特征,并比较其诊断价值.结果:成神经细胞瘤骨转移89.2%位于长管状骨、骨盆、头颅和脊柱.形态上包括溶骨型(71.4%)、混合型(28.6%)和单纯成骨型.X线和CT表现为虫蚀样、不规则、极小透光区,部分伴有硬化边缘或骨膜反应.CT在头颅、骨盆、椎体等部位显示更细微、更广泛的病变.MRI骨髓侵犯表现为T1WI低信号,T2WI高信号,MRI发现髓内转移的时间早于CT和X线,显示病变范围更大.结论:X线平片是诊断成神经细胞瘤骨转移的基本影像学方法,为观察长骨转移最佳方法;CT利于显示骨结构重叠较多部位的病变和细节;MRI早期发现髓内、椎管内转移.     

骨肉瘤的X线平片、CT、MRI诊断

目的:评估X线平片、CT、MRI诊断骨肉瘤的价值.材料和方法:回顾性分析20例经手术病理证实为骨肉瘤的X线平片、CT、MRI表现.结果:20例X线平片均能清楚显示骨肉瘤的基本表现,术前正确诊断17例,误诊3例;CT显示骨肉瘤的骨质破坏及瘤骨优于X线平片11例;MRI显示骨肉瘤的早期骨破坏及周围软组织、病变范围及骨骺(骺板)侵袭、瘤周水肿优于X线平片及CT14例.结论:X线平片是诊断骨肉瘤的首选及基本方法,CT或MRI对提高骨肉瘤的诊断、分期及临床治疗提供全面、准确的影像学资料,尤其MRI对于指导保留骨骺的保肢术的选择具有重要意义.     

非管状骨骨巨细胞瘤的影像学诊断

目的 探讨非管状骨骨巨细胞瘤的X线平片、CT和MRI表现,评价X线平片、CT和MRI对该病的诊断价值.方法 对经手术病理证实的17例非管状骨巨细胞瘤患者的影像学资料进行回顾性分析.17例均行X线平片检查,11例行CT扫描,8例行MRI检查.结果 大部分病变表现具有长管状骨病变的特征,但也有其自身特点.其中膨胀性囊性骨质破坏8例,溶骨性骨质破坏9例,偏心性邻关节生长5例,形成软组织肿块4例,有硬化边1例.结论 X线平片可作为诊断非管状骨骨巨细胞瘤的初步筛选方法,CT和MRI可为本病的诊断与鉴别诊断提供更多有价值的信息.     

膝关节类风湿关节炎MRI与X线平片对比

目的　评价MRI与X线平片在膝关节类风湿关节炎中的诊断价值。方法　 34个膝关节行MRI与X线检查 ,13例进行了MRI增强扫描。结果　MRI显示 34个膝均存在骨破坏 ,2 1个膝骨硬化 ,2 2个半月板有信号改变 ,15个膝关节软骨信号改变 ,10个膝胫骨移位 ,8个膝后交叉韧带拉直 ,13例MRI增强扫描显示血管翳附着、滑膜增殖和关节积液。X线显示 1个膝有骨破坏 ,11个膝伴骨硬化 ,16个膝关节间隙狭窄 ,8个膝胫骨移位。结论　MRI诊断膝关节类风湿关节炎优于X线平片     

骨挫伤的MRI诊断价值

目的探讨骨挫伤的MRI影像表现及MRI在骨挫伤影像诊断中的价值.方法回顾性分析34例骨挫伤和3例隐匿性骨折病例的X线平片、CT及MRI影像资料,分析骨挫伤的MRI影像表现,评估X线平片、CT及MRI在骨挫伤影像诊断中的作用.结果全部病例的X线平片均未见异常.CT能有效显示3例隐匿性骨折的部位和形态,但34例骨挫伤病例CT均未能予以诊断.3例CT诊断为隐匿性骨折的病例MRI诊断为骨挫伤而未能显示骨折的存在.MRI能有效显示不同部位骨挫伤的病变部位、范围及形态,在SE序列上骨挫伤的典型MRI表现为不规则片状T1WI低信号、T2WI高信号的异常信号改变,骨皮质及骨轮廓不发生变化.结论在X线平片、CT及MRI三种影像检查方法中,MRI是唯一能有效诊断骨挫伤的检查方法,但MRI不能明确区别骨挫伤和未分离、移位的隐匿性骨折.     

脊柱结核的影像学诊断

目的：评价X线平片、CT、MRI在脊柱结核的诊断价值。方法：回顾40例经手术病理或临床结果证实为脊柱结核病人的X线平片、CT、MRI影像表现。结果：X线平片可了解椎体破坏、塌陷、椎间隙变窄情况，及脊柱是否后凸畸形。40例CT均可较清楚显示椎体骨质破坏的数目（有21例分别两个椎体受累）、范围及病变是否进入椎管，其中19例形成寒性脓疡。9例行MRI均可显示椎体骨质破坏，周围软组织肿胀、寒性脓疡范围，及椎管、脊髓情况。结论：X线平片结合CT平扫可对脊柱结核进行较全面细致的观察并做出诊断。与肿瘤不易鉴别时需加CT增强扫描。若有神经症状时应补充MRI检查。     

脊索瘤的影像学分析

目的：分析脊索瘤的影像学表现，探讨其影像学诊断价值。资料与方法：收集经手术病理证实的12例脊索瘤，所有病例均摄X线平片，其中CT检查8例，MRI检查4例。结果：骶尾部脊索瘤7例，表现为囊性膨胀性及溶骨性骨质破坏，骨壳完整或不完整，骨破坏区内可见散在分布的斑片状、斑点状钙化，周围可见软组织肿块；颅底部脊索瘤4例，表现为溶骨性膨胀性骨质破坏及软组织肿蚨，内可见囊变、出血及钙化灶；腰椎1例，表现为椎体溶骨性骨质破坏及软组织肿块，内可见斑点状钙化。MRI表现为病变呈不均匀长T1、长T2信号，增强扫描表现为不均匀“蜂窝样”强化。结论：通过影像学检查，并结合临床，大部分脊索瘤术前能够正确诊断；CT较X线平片能够更好的显示病变结构及邻近软组织改变；MRI能够精确显示病变范围及周围血管神经的关系，有助于制定合适的手术方案和预后的估计。     

骨肉瘤X线平片、CT和MRI征象对比分析

目的 探讨骨肉瘤X线平片、CT和MRI的表现及其对骨肉瘤的诊断价值.方法 回顾性分析34例影像学资料完整并经病理证实的骨肉瘤,对骨肉瘤同一征象在不同检查方法的表现进行界定、观察、记录及统计学分析.结果 ①X线平片和CT显示瘤骨呈高密度,MRI显示絮状瘤骨6例.2例针状瘤骨在X线和CT不能显示,MRI呈长T1短T2信号.②MRI能显示X线平片和CT不能显示的骨膜反应和骨膜三角9例和4例.③骨皮质破坏:X线平片和CT显示骨皮质破坏的形态.MRI能显示骨皮质破坏的病理基础.④干骺端或骨端松质骨在X线平片和CT呈溶骨、成骨或混合性改变,MRI呈长T1长T2和(或)长T1短T2信号.⑤骨干髓腔病变:X线平片能显示肿瘤骨,CT显示液-液平面3例,MR上,19例能分清肿瘤实质与瘤周水肿.⑥骺板(痕)及骨骺侵犯:X线平片和CT能显示骨质破坏和肿瘤骨,MRI还能显示骺板(痕)及骨骺瘤周水肿.⑦肿块与软组织肿胀:X线平片显示3例有钙化的软组织肿块边缘清楚,而CT和MRI显示软组织肿块均边缘清楚,分别为28例和32例;X线平片不能显示软组织肿胀.结论 X线、CT和MRI在显示骨肉瘤的征象方面各具特点,三者互补可提高诊断的正确率.     

骨肿瘤及肿瘤样病变平片及CT诊断(附120例分析)

目的：比较和评价Ｘ线平片及ＣＴ两种影像学方法在骨肿瘤及肿瘤样病变诊断中的作用。方法：回顾性分析我院１９９１－０１～１９９７－０９行Ｘ线平片及ＣＴ扫描检查，并经临床和／或活检、手术病理证实的１２０例骨肿瘤及肿瘤样病变。就瘤骨形成、瘤软骨钙化、骨质破坏、骨膜反应、软组织肿块和病变与邻近组织间的关系等方面进行对照观察。结果：ＣＴ显示骨肿瘤及肿瘤样病变的骨质破坏、软组织肿块和病变与邻近组织间的关系方面比Ｘ线平片较敏感和较明确。结论：虽然ＣＴ扫描对骨肿瘤及肿瘤样病变的某些征象的显示优于Ｘ线平片，但Ｘ线平片仍是骨肿瘤和肿瘤样病变影像学诊断的最基本的和首选的检查方法     

Osteomyelitis of the foot in diabetic patients: evaluation with plain film, 99mTc-MDP bone scintigraphy, and MR imaging

Diagnosis of osteomyelitis of the foot in diabetic patients may be difficult because of the coexistence of chronic cellulitis, vascular insufficiency, and peripheral neuropathy. This study compared the diagnostic accuracies of plain films, bone scans, and MR imaging studies in diabetic patients with suspicion of osteomyelitis of the foot. Twenty-nine plain radiographs, 20 bone scans, and 30 MR studies were obtained in 24 patients. Twenty-nine bones from 14 patients were pathologically proved either positive (25 bones) or negative (four bones) for osteomyelitis. Another 15 bones (10 patients) studied with MR had no pathologic proof, but the bones healed with only local wound care and/or a short course of oral antibiotics. These patients had trauma, cellulitis, or unhealed ulcers. The sensitivity and specificity of plain films were both 75%. Bone scans had a very low specificity (100% false-positive rate). A negative bone scan should strongly exclude the probability of osteomyelitis. Unlike the findings in previous reports, MR had much higher sensitivity and specificity than bone scans in detecting osteomyelitis in diabetic patients. When the 10 patients without pathologic proof (those who presumably had neuroarthropathy, vascular insufficiency, and/or cellulitis) were included, the sensitivity and specificity of all three techniques decreased. Our experience with this small group of patients suggests that MR is a useful imaging technique for diagnosing osteomyelitis of the foot in diabetic patients.     

Role of magnetic resonance imaging in the evaluation of diabetic foot with suspected osteomyelitis

Purpose

This study evaluated Magnetic Resonance Imaging (MRI) in infected diabetic foot ulcers.

Materials and methods

Sixteen diabetic patients underwent foot MRI between January 2006 and September 2007 for suspected unilateral osteomyelitis. Three of 16 patients showed radiographic changes due to Charcot neuropathic osteoarthropathy. Twelve of 16 patients also underwent MR angiography of the lower limbs for the purpose of planning surgical or endovascular treatment. The musculoskeletal and vascular MRI studies were retrospectively reviewed by three radiologists.

Results

The final diagnosis, based on clinical, imaging, microbiological and histological findings, was osteomyelitis in 13/16 cases. Foot MRI allowed a correct diagnosis in 15/16 patients, with 1 false positive result demonstrated by computed tomography (CT)-guided bone biopsy. MR angiography of the lower limbs was considered nondiagnostic in 5/12 patients in the infrapopliteal region owing to venous contamination.

Conclusions

MRI has high sensitivity for the detection of osteomyelitis in the diabetic foot but lower specificity related to Charcot neuropathic osteoarthropathy. If diagnostic uncertainty persists, a bone biopsy is indicated. The inflammatory hyperaemia caused by the ulcer deteriorates the diagnostic quality of 40%–50% of MR angiography studies in the infrapopliteal region. In these cases, selective arteriography is appropriate, as it can be performed in the same session as angioplasty.     

Diagnosis of osteomyelitis of the foot in diabetic patients: value of 111In-leukocyte scintigraphy

The noninvasive diagnosis of osteomyelitis of the foot in diabetic patients with currently available radiologic and radionuclide imaging techniques is often difficult. Recently, 111In-labeled leukocyte scintigraphy has been proposed as an attractive alternative. Accordingly, we retrospectively reviewed 51 111In-labeled leukocyte scans, 49 technetium-99m bone scans, and 49 plain radiographs obtained in 51 adults with diabetes in whom osteomyelitis of the foot was suspected. The sensitivity and specificity of these techniques were evaluated in all patients, as well as in a subgroup of 11 patients with neuroarthropathy. Results with 111In-labeled leukocyte scans were also examined in subsets of patients with soft-tissue ulcers (n = 35) and those receiving antibiotics during investigation (n = 20). Confirmation or exclusion of osteomyelitis was made surgically in 28 patients and clinically in 23. Fourteen patients had osteomyelitis. Bone scans were most sensitive (93%) but least specific (43%); plain radiographs were most specific (83%) but least sensitive (43%). 111In-labeled leukocyte scans were both sensitive (79%) and specific (78%), and remained useful in patients with neuroarthropathy, soft-tissue ulcers, and antibiotic treatment. Poor spatial resolution contributed to the false-negative and false-positive 111In-labeled leukocyte scans, suggesting that this technique should not be interpreted independent of other tests. 111In-labeled leukocyte scans are a valuable diagnostic tool for the diagnosis of pedal osteomyelitis in diabetic patients.     

Potential role of FDG PET in the setting of diabetic neuro-osteoarthropathy: can it differentiate uncomplicated Charcot's neuroarthropathy from osteomyelitis and soft-tissue infection?

BACKGROUND: This paper is based on the results from an ongoing prospective trial designed to investigate the usefulness of FDG PET in the complicated diabetic foot. AIM: To investigate the potential utility of FDG PET imaging in the setting of acute neuropathic osteoarthropathy (Charcot's foot). PATIENTS AND METHODS: A total of 63 patients, in four groups, were evaluated. The groups were: (A) 17 patients with a clinical diagnosis of Charcot's neuroarthropathy (11 men, six women; mean age: 59.4+/-8.6 years); (B) 21 patients with uncomplicated diabetic foot (16 men, five women; mean age: 63+/-10 years); (C) 20 non-diabetic patients with normal lower extremities (12 men, eight women; mean age 54+/-19 years); and (D) five patients with proven osteomyelitis secondary to complicated diabetic foot (three men, two women; mean age: 61.2+/-13.9 years). Five patients in group A had foot ulcer and intermediate to high degree of suspicion for superimposed osteomyelitis. Each subject underwent FDG PET imaging of the lower extremities in addition to MRI and the findings were compared with the final diagnostic outcome based on histopathology and clinical follow-up. The images were examined visually for focal abnormalities. Regions of interest were assigned to the sites of abnormal FDG uptake for calculating maximum standardized uptake value (SUVmax). Two important clinical decision-making issues were explored: (1) whether FDG PET shows a definitive uptake pattern in Charcot's neuroarthropathy and if so whether that could be utilized to differentiate it from other complicated forms of diabetic foot like osteomyelitis and cellulitis, which is frequently a diagnostic challenge in this clinical setting; and (2) how accurate FDG PET is in detection soft tissue infection in patients with Charcot's foot. These issues were examined by utilizing FDG PET findings along with MRI results in the same patient. RESULTS: We observed a low degree of diffuse FDG uptake in the Charcot's joints. This was clearly distinguishable from the normal joints. The SUVmax in the Charcot's lesions varied from 0.7 to 2.4 (mean, 1.3+/-0.4) while those of midfoot of the normal control subjects and the uncomplicated diabetic foot ranged from 0.2 to 0.7 (mean 0.42+/-0.12) and from 0.2 to 0.8 (mean 0.5+/-0.16), respectively. The only patient with Charcot's foot with superimposed osteomyelitis had an SUVmax of 6.5. The SUVmax of the sites of osteomyelitis as a complication of diabetic foot was 2.9-6.2 (mean: 4.38+/-1.39). Unifactorial analysis of variance test yielded a statistical significance in the SUVmax between the four groups (P<0.01). The SUVmax between the normal control groups and the uncomplicated diabetic foot was not statistically significant by the Student's t-test (P>0.05). In the setting of concomitant foot ulcer FDG PET accurately ruled out osteomyelitis. Overall sensitivity and accuracy of FDG PET in the diagnosis of Charcot's foot was 100 and 93.8%, respectively; and for MRI were 76.9 and 75%, respectively. FDG PET showed foci of abnormally enhanced uptake in the soft tissue which was suggestive of inflammation in seven cases (43.75%) which were proven pathologically to be secondary to infection. In only two of these cases the features of soft tissue infection were noted on the magnetic resonance images. CONCLUSION: The results support a valuable role of FDG PET in the setting of Charcot's neuroarthropathy by reliably differentiating it from osteomyelitis both in general and when foot ulcer is present.     

骨髓炎的MRI诊断

目的:探讨MRI在骨髓炎诊断中的价值。方法:回顾分析20例骨髓炎的X线、MRI平扫及Gd-DTPA增强扫描资料。结果:MRI最早可在发病第3天发现骨髓信号异常,骨髓炎在MRI上表现出T1WI为低或稍低信号,在T2WI上呈高信号,以STIR或FFE序列最明显,Gd-DTPA扫描病变不均匀强化,骨髓炎多有脓肿和脓肿壁环状强化。结论:MRI对骨髓炎的诊断具有重要价值,尤其在显示早期病变及病变范围方面明显优于X线。     

放射性核素显像在糖尿病足诊治中的应用

早期、准确地诊断糖尿病足的微血管、血流改变以及感染是取得治疗成功的关键。放射性核素显像可以为糖尿病足的发生、发展提供重要信息,在对糖尿病足的早期改变、糖尿病足部骨髓炎的诊断以及对溃疡的预后估计具有重要作用。     

Evaluation of infectious diabetic foot complications with indium-111-labeled human nonspecific immunoglobulin G.

Osteomyelitis of the foot is a well-known complication of diabetes mellitus. In this study, the validity of 111In-labeled human nonspecific immunoglobulin G (IgG) scintigraphy was studied in 16 diabetic patients with foot ulcers, gangrene or painful Charcot joints. In all patients, plain radiographs, conventional bone scan images and 111In-IgG images were recorded. The results were verified by histologic examination of surgical specimens in patients who did not respond to antibiotic treatment within 2-3 wk (10 lesions) or long-term clinical follow-up of at least 6-mo (16 lesions). On the bone scans, all seven osteomyelitic foci were detected. However, 19 additional foci not due to osteomyelitis were seen. The absence of true-negative bone scans in this study resulted in a specificity of 0%. On the plain radiographs, four of seven osteomyelitis foci were detected; for 111In-IgG scintigraphy, six of seven (sensitivity 57% and 86%, respectively). Plain radiographs correctly ruled out osteomyelitis in 15 of 19 lesions, 111In-IgG scintigraphy in 16 of 19 (specificity 79% and 84%, respectively). All imaging procedures gave false-positive results in penetrating ulcers over the calcaneus in two patients and in one patient with a Charcot joint, most likely due to recent fractures. A false-negative 111In-IgG study was observed in a patient with severe arterial angiopathy. Accurate estimation of probable osteomyelitis was not possible from the results of soft-tissue cultures, since in only 6 of 12 positive cultures, osteomyelitic foci could be proven. Indium-111-IgG scintigraphy can contribute to adequate evaluation of osteomyelitis in diabetic foot complications because it improves specificity when compared to bone scan and radiographic findings and improves sensitivity in comparison to plain radiographs.     

How to synthesize evidence for imaging guidelines

AIM: To provide guidance on how to gather and evaluate evidence from the literature on the efficacy of imaging, using as an example the assessment of the role of magnetic resonance imaging (MRI) in the diagnosis of osteomyelitis. This method was adopted for evaluating evidence for the musculoskeletal section of the 5th edition of the Royal College of Radiologists' (RCR) guidelines. MATERIALS AND METHODS: A systematic review of the literature published between 1966 and July 2001 was carried out. Eligible articles described studies in patients with suspected osteomyelitis and who were diagnosed using MRI. Search strategies were developed to identify relevant imaging studies. Studies included in the systematic review were selected using predefined criteria. The sensitivity, specificity, accuracy and likelihood ratios for MRI reported in the studies were used to evaluate the value of the procedure in osteomyelitis. Where the above were not reported, they were calculated by the reviewers. RESULTS: The average sensitivity of MRI in osteomyelitis was 91% (range 76-100%), the average specificity was 82% (range 65-96%), average accuracy was 88% (range 71-97%), and the average positive likelihood ratio was 7.8 (range 2.3-21.1). Four studies evaluated the use of MRI in the diagnosis of osteomyelitis in the diabetic foot, two in osteomyelitis of the lower extremities, while four each evaluated the use of MRI in vertebral osteomyelitis, in the diagnosis of any form of osteomyelitis, osteomyelitis in spinal cord-injured patients and in cranial osteomyelitis. CONCLUSION: Systematic reviews of literature can be used to obtain evidence on the value of imaging procedures. The quality of the studies included in the review should always be considered when selecting studies to limit bias. In our example, MRI appears sensitive, specific and accurate in the diagnosis of osteomyelitis at different sites.     

Imaging of the diabetic foot

Destruction in diabetic feet is secondary to neuropathy (peripheral and autonomic nervous system) in association with microangiopathy. The loss of sensation to pain and the static trouble lead to increase the pressure in some areas and predispose to pedal skin ulceration, the precursor of osteomyelitis. Plain radiography should be the first step in the evaluation for diagnosis and follow-up. The initial patterns are nonspecific but very rapid evolution associating osteolysis, osteosclerosis and fragmentation lead to the Charcot foot. When osteomyelitis is suspected, scintigraphy with labelled white blood cells and MRI are necessary to differentiate infection from neuropathy.     

The diabetic foot

Foot complications in diabetics often lead to amputation. Ulceration is the most common complication in the diabetic forefoot and underlies more than 90% of cases of pedal osteomyelitis. The diagnosis of osteomyelitis is, nevertheless, difficult, and imaging is an important part of the work-up. Plain radiographs, although useful for anatomical information, are neither sensitive nor specific. Three-phase bone scintigraphy is sensitive but not specific. Labelled leucocyte scintigraphy and MRI are both useful and are complementary to one another. Labelled leucocyte scintigraphy is valuable for diagnosis as well as follow-up of pedal osteomyelitis. MRI offers exquisite anatomical detail, which is invaluable for guiding surgical management. The principal complication in the mid and hind foot is the neuropathic or Charcot joint. Although infection of the neuropathic joint is infrequent, its diagnosis is difficult. The extensive bony changes that accompany this disorder severely diminish the value of radiography and bone scintigraphy. It is not always possible to distinguish the marrow oedema of neuropathy from that of osteomyelitis and the role of MRI in the evaluation of this entity is still uncertain. Uptake of labelled leucocytes in the absence of infection may occur and is owing, at least in part, to haematopoietically active marrow. Combined leucocyte/marrow scintigraphy holds considerable promise for identifying the infected Charcot joint.