99Tcm-MDP骨三相定量法鉴别关节置换术后感染及松动

目的 以定量法研究99Tcm-MDP骨三相显像在鉴别骨关节置换术后无菌性及感染性假体松动中的价值.方法 回顾性分析28例关节置换术后出现疼痛而再次就诊患者[男9例、女19例,年龄49～80(平均67.5)岁]的骨三相显像,在血流、血池、静态3个时相分别勾画患侧与健侧关节ROI,选区域内最大计数计算患侧与健侧比值.将各比值及血红细胞沉降率、C反应蛋白等检查结果进行ROC曲线分析.最终诊断以手术病理及细菌培养结果为准.各指标AUC越大,诊断效能越高,依据较为理想的灵敏度和特异性选择最佳截断值.结果 28例中,感染性松动者9例,无菌性松动17例,股骨大转子滑囊炎1例,缝线反应1例.如果以血流或血池显像阳性为诊断感染性松动的标准,骨显像的灵敏度、特异性及准确性分别为7/9,78.9％(15/19)和78.6％(22/28).血池相计数比值的ROC AUC为0.942,最佳截断值为1.40时灵敏度和特异性可达8/9和78.9％(15/19).血流相计数比值的ROC AUC为0.816,最佳截断值为1.53.C反应蛋白的ROC AUC为0.795,最佳截断值为1.20.血红细胞沉降率的ROC AUC为0.722,静态相计数比值的ROC AUC为0.474(均P＞0.05).结论 以定量的方法分析骨三相显像在诊断假体置换术后有无合并感染,其诊断效能高于定性方法,其中血池显像的诊断价值最高.     

Three-phase bone scintigraphy pattern of loosening in uncemented hip prostheses

The three-phase bone scintigraphy pattern of loosening in uncemented hip prostheses (UHPs) has not previously been elucidated. We evaluated 28 patients with complicated UHPs who had undergone total hip arthroplasty a very long time previously (range 3–20 years, mean 8.4). All the patients were surgically reviewed: 26 UHPs were found to be loosened and two infected. Nine asymptomatic UHPs were taken as controls. The dynamic phase was invariably negative in both loosened and asymptomatic UHPs while markedly positive in the infected ones. The blood pool phase was positive to various degrees in 16 of the 26 loosened UHPs as well as in the infected UHPs, but was invariably negative in painless replacements. In the bone phase, areas of significantly (discrete to marked) increased uptake were observed in all the loosened prostheses as well as in two-thirds of the asymptomatic ones. However, the regions of the lesser trochanter and/or tip and/or shaft were involved exclusively in the case of the loosened UHPs, and diffuse periprosthetic uptake was found only with loosened or infected implants. Areas of slight methylene diphosphonate (MDP) uptake were found at every periprosthetic site and areas of discrete to marked MDP uptake were commonly found in the acetabulum and/or the greater trochanter with both loosened and painless prostheses and are thus considered to be nonspecific findings.     

Whole-body MR imaging for detection of bone metastases in children and young adults: comparison with skeletal scintigraphy and FDG PET.

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of whole-body MR imaging, skeletal scintigraphy, and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for the detection of bone metastases in children. SUBJECTS AND METHODS: Thirty-nine children and young adults who were 2--19 years old and who had Ewing's sarcoma, osteosarcoma, lymphoma, rhabdomyosarcoma, melanoma, and Langerhans' cell histiocytosis underwent whole-body spin-echo MR imaging, skeletal scintigraphy, and FDG PET for the initial staging of bone marrow metastases. The number and location of bone and bone marrow lesions diagnosed with each imaging modality were correlated with biopsy and clinical follow-up as the standard of reference. RESULTS: Twenty-one patients exhibited 51 bone metastases. Sensitivities for the detection of bone metastases were 90% for FDG PET, 82% for whole-body MR imaging, and 71% for skeletal scintigraphy; these data were significantly different (p < 0.05). False-negative lesions were different for the three imaging modalities, mainly depending on lesion location. Most false-positive lesions were diagnosed using FDG PET. CONCLUSION: Whole-body MR imaging has a higher sensitivity than skeletal scintigraphy for the detection of bone marrow metastases but a lower sensitivity than FDG PET.     

11C-choline PET for the detection of bone and soft tissue tumours in comparison with FDG PET

We assessed and compared the usefulness of C-choline positron emission tomography (PET) with that of 2-[ F]fluoro-2-deoxy-D-glucose (FDG) PET for the differentiation between benign and malignant bone and soft tissue tumours. A total of 43 patients with 45 lesions were included. C-choline PET and FDG PET were performed from 5 and 40 min, respectively, after injection of 275-370 MBq tracer. PET data were evaluated by using the standardized uptake value (SUV) and were analysed according to the pathological data. C-choline uptake in malignancies was 4.9+/-2.1 (n=14), which was significantly higher than that in benign lesions (2.5+/-1.7, n=31) (P <0.0001). The sensitivity, specificity and accuracy of C-choline PET were 100%, 64.5% and 75.6%, respectively, when 2.59 of the SUV was used as the cut-off value. The FDG uptake in malignancies was 5.1+/-4.2 (n=14) and was also significantly larger than that in benign lesions 2.9+/-2.9 (n=31) (P<0.003). The sensitivity, specificity and accuracy of FDG PET were 85.7%, 41.9% and 55.6%, respectively (cut-off=1.83). The C-choline uptake in the lesions correlated with FDG uptake ( r=0.61, P<0.003). In receiver operating characteristic (ROC) analysis, the area under the ROC curve for C-choline PET (area=0.847) was higher than that for FDG PET (area=0.717). This study showed that C-choline PET was superior to FDG PET in differentiation between malignant and benign lesion in bone and soft tissue tumours. C-choline PET might be useful as a screening method for malignant bone and soft tissue tumours.     

Indium-111-chloride and three-phase bone scintigraphy: a comparison for imaging experimental osteomyelitis

To investigate the utility of indium-111-chloride (111In-Cl) imaging in detecting osteomyelitis complicating surgical or fracture sites, the proximal tibia of 11 dogs were experimentally infected with Staphylococcus aureus after creation of a cortical defect. The contralateral limb served as a sham-operated control. Animals were serially imaged by radiography, three-phase technetium-99m-methylene diphosphonate (99mTc-MDP) scintigraphy, and 111In-Cl scintigraphy. There was a significant difference between infected (1.93) and noninfected (1.32) limb's tibia/femur count density ratios on 24-hr (p = 0.0001) and 72-hr (p = 0.0001) 111In-Cl images. A smaller difference was found for 99mTc-MDP bone-phase tibia/femur ratios (p = 0.0199). Using receiver operator characteristic analysis of tibia/femur ratios, a sensitivity of 61%, specificity of 88%, and positive (75%) and negative (79%) predictive values were determined for the 24-hr 111In-Cl images. Indium-111-chloride was superior to 99mTc-MDP in differentiating infected and noninfected operative sites.     

FDG PET can replace bone scintigraphy in primary staging of malignant lymphoma.

Recent studies indicated that 18F-fluorodeoxyglucose (FDG) PET may be more accurate than CT in staging nodal and extranodal malignant lymphoma. The objective of this study was to compare conventional bone scintigraphy as an established skeletal staging procedure with PET using FDG in the detection of osseous involvement in malignant lymphoma. METHODS: Whole-body PET-based staging studies of 56 consecutive patients with proven Hodgkin's disease (n = 34) or non-Hodgkin's lymphoma (n = 22) were compared with the results of bone scintigraphy. Positive PET or bone scintigraphic findings were confirmed, if possible, by biopsy, MRI, CT or radiographic investigations. RESULTS: Of the 56 patients studied, 12 were found to have skeletal involvement on both studies (PET, 30 regions; bone scintigraphy, 20 regions). Findings were confirmed in all 12 patients. FDG PET detected an additional 12 involved regions in 5 patients. This was subsequently verified in 3 patients, although the other 2 cases remained unresolved. Conversely, bone scintigraphy revealed five abnormalities compatible with lymphoma in 5 patients. Three of these lesions were found to be erroneous; final evaluation of the remaining two findings was not possible. CONCLUSION: FDG PET is suitable for identifying osseous involvement in malignant lymphoma with a high positive predictive value and is thereby more sensitive and specific than bone scintigraphy.     

The pitfalls of planar three-phase bone scintigraphy in nontraumatic hip avascular osteonecrosis.

PURPOSE: This study documented the previously reported lower sensitivity of routine planar three-phase bone scintigraphy (BS) performed using a high-resolution parallel-hole collimator compared with MRI to diagnose nontraumatic avascular necrosis of the hip (AVN). METHODS: Six observers reviewed 143 bone scintigrams obtained in patients with nontraumatic hip pain (n = 120) or a control group (n = 23). All patients had a standard radiograph and MRI within 2 months of the BS. Of 280 hips, 148 (53%) were painful on the day of the examination. The osteonecrosis group (AVN) consisted of 93 instances of AVN in 58 patients. Although it departs from the clinical situation, this method evaluated the intrinsic performance of the imaging method. The data were analyzed using a receiver operating characteristic method. RESULTS: For the six observers, the A(z) values were 0.65, 0.67, 0.66, 0.67, 0.73, and 0.79, respectively, and 0.66, 0.71, 0.75, 0.81, 0.81, 0.82, and 0.84 after removing hip diseases other than AVN through data manipulation. Bone marrow edema, as seen on MRI, was the most frequently reported misleading sign in false-positive diagnoses, especially in the early or late phases of the disease. False-negative diagnoses misclassified the scans as "asymptomatic hips" in 28 of 30 cases. Twenty-two of 30 scans appeared normal, but these AVN lesions were small (<25%) and were discovered by chance on MRIs that displayed bilateral involvement associated with radiographic evidence (stage 0 or 1). Thirteen of 20 patients were followed for 3 or more years, and only one worsened. CONCLUSIONS: BS is not indicated to diagnose possible contralateral AVN if the hip is asymptomatic. This study emphasizes the results from the literature; if indicated, a radionuclide hip investigation requires the use of a pin-hole collimator, a SPECT study with scatter correction and iterative reconstruction algorithms, or both.     

Diagnosis of bone metastases: a meta-analysis comparing 18FDG PET, CT, MRI and bone scintigraphy

Objective  

To perform a meta-analysis to compare ¹⁸FDG PET, CT, MRI and bone scintigraphy (BS) for the diagnosis of bone metastases.     

Meta分析比较18FDG-PET、CT、MRI及放射性核素骨显像对骨转移的诊断

目的采用Meta分析比较18FDG-PET、CT、MRI及放射性核素骨显像(BS)对骨转移瘤的诊断价值。方法通过MEDLINE、EMBASE数据库检索自1995年—2010年发表的相关原始文献。运用软件进行Meta分析,计算总敏感     

Does technetium scintigraphy in combination with gallium scintigraphy improve the differential diagnosis of aseptic and septic endoprosthesis loosening?

In the majority of cases, 3-phase scintigraphy using Tc99m phosphate complexes is sufficient to diagnose a septic (infective) loosening of an endoprosthesis (hip or knee). Additional Ga 67 citrate scintigraphy should be considered only if technetium scintigraphy fails to supply an unequivocal finding. This is explained by the authors in detail.     

Initial stage of Legg-Calve-Perthes disease: comparison of three-phase bone scintigraphy and SPECT with MR imaging.

Twenty-one patients with initial stage Legg-Calve-Perthes (LCP) disease were examined by three-phase bone scintigraphy, single photon emission scintigraphy (SPECT), and magnetic resonance (MR) imaging. On dynamic study, increased activity was present in the epiphysis or the growth plate in 39%; the corresponding figure for blood-pool images was 94%. Pinhole images demonstrated the lateral stripe of revascularization in 57% of patients. Decreased signal intensity in the epiphysis on T1-weighted images proved to be the most sensitive indicator of epiphyseal necrosis on MR imaging and was absent in only 10% of the cases. The subchondral fracture occurred in 62% (including the above 10% of cases), identified by T1-weighted image. Cartilaginous hypertrophy, detected by T1-weighted image, had a high incidence (81%). Joint effusion was identified on T2-weighted images in 90% of patients. The cross-sectional views provided by SPECT and MR imaging permits a better appreciation of the extent of epiphyseal necrosis in LCP disease.     

Root fracture detection: a comparison of direct digital radiography with conventional radiography

OBJECTIVES: To compare the diagnostic potential of direct digital radiography with conventional film for detecting experimental root fractures. METHODS: Two hundred and one extracted single-rooted human teeth were endodontically instrumented and divided into two groups, a control group of 100 teeth and a fractured group of 101 teeth in which root fractures were produced experimentally. Each tooth was imaged using the paralleling technique with a CCD-based digital system and D-speed film. The images were interpreted by an experienced radiologist without prior knowledge of the distribution of the root fractures. The degree of agreement in detecting root fractures with each imaging system compared with the actual condition was expressed as the kappa value. The difference between the radiographic systems was then assessed by chi(2)-test at the 95% significance level. RESULTS: There was substantial agreement between the digital system and the actual condition (kappa=0.71; 95% Confidence Interval: 0.62 to 0.80) and close agreement between the film and the actual condition (kappa=0.63; 95% Confidence Interval: 0.53 to 0.74). However, this difference was not significantly different (P=0.2). CONCLUSIONS: The performance of CCD-based digital radiography in detecting root fractures is similar to film-based radiography.