18F-NaF PET/CT骨显像在甲状旁腺功能亢进性骨病中的应用

目的 探讨甲状旁腺功能亢进性骨病18F-NaF PET/CT骨显像的影像学特点及其应用价值。 方法 收集30例经临床及术后病理证实为甲状旁腺功能亢进症患者[男性11例、女性19例,年龄18～71（52.3±13.5）岁]的18F-NaF PET/CT骨显像及99Tcm -亚甲基二膦酸盐（99Tcm-MDP）全身骨显像资料,回顾性分析其18F-NaF PET/CT骨显像特点,对比两种骨显像方法对该病局部骨骼病灶的检出情况,并根据Mirels评分标准对棕色瘤进行评分。 结果 两种骨显像方法定性结果一致,即骨显像阴性15例,阳性15例。甲状旁腺功能亢进性骨病在18F-NaF PET图像上大部分表现为以全身多骨弥漫性骨代谢增高为主的多种代谢性骨病征象,并发棕色瘤、骨硬化及病理性骨折等时表现为单发或多发局灶性显像剂异常分布,其中棕色瘤表现为局灶性显像剂浓聚、显像剂稀疏或病灶中心显像剂分布缺损伴边缘显像剂不均匀浓聚;同机CT图像上均表现为全身多骨多种形式的骨质吸收,其中,表现为广泛骨质疏松13例、伴棕色瘤7例、骨质硬化6例、骨质软化3例、病理性骨折3例。15例甲状旁腺功能亢进性骨病患者共检出局部骨骼病灶（棕色瘤、骨硬化、病理性骨折、假骨折）53个,其中,18F-NaF PET/CT骨显像全部检出,99Tcm-MDP全身骨显像检出32个。7例甲状旁腺功能亢进性骨病患者伴棕色瘤,位于长骨的棕色瘤病灶数共24个,其中9个Mirels评分大于9分。 结论 甲状旁腺功能亢进性骨病在18F-NaF PET/CT骨显像上的全身骨代谢及解剖学表现有一定的特征性表现,18F-NaF PET/CT骨显像结合同机CT上全身骨骼病灶的详细信息,在甲状旁腺功能亢进性骨病的诊断、鉴别诊断及病情严重程度评估中有更好的应用价值。     

Distinguishing stress fractures from pathologic fractures: a multimodality approach

Whereas stress fractures occur in normal or metabolically weakened bones, pathologic fractures occur at the site of a bone tumor. Unfortunately, stress fractures may share imaging features with pathologic fractures on plain radiography, and therefore other modalities are commonly utilized to distinguish these entities. Additional cross-sectional imaging with CT or MRI as well as scintigraphy and PET scanning is often performed for further evaluation. For the detailed assessment of a fracture site, CT offers a high-resolution view of the bone cortex and periosteum which aids the diagnosis of a pathologic fracture. The character of underlying bone marrow patterns of destruction can also be ascertained along with evidence of a soft tissue mass. MRI, however, is a more sensitive technique for the detection of underlying bone marrow lesions at a fracture site. In addition, the surrounding soft tissues, including possible involvement of adjacent muscle, can be well evaluated with MRI. While bone scintigraphy and FDG-PET are not specific, they offer a whole-body screen for metastases in the case of a suspected malignant pathologic fracture. In this review, we present select examples of fractures that underscore imaging features that help distinguish stress fractures from pathologic fractures, since accurate differentiation of these entities is paramount.     

Nuklearmedizinische Untersuchungsmöglichkeiten des Skelettsystems

Eventhough new diagnostic methods, as CT/MRI, are widely available, the bone scintigraphy still does remain an important tool for imaging bone pathology. An increase in diagnostic accuracy is possible by using different imaging modalities: wholebody scan, threephase bone scintigraphy and SPECT. For this reason, the bone scintigraphy can be used for diagnosis of tumors/infections and therapy monitoring. Applying these methods, important informations can be gained for differential diagnosis. The bone scintigraphy is easy to perform, allows good whole-body overview by low radiation burden to the patient.     

Nuclear medicine study potentials in diseases of the skeletal system

Even though new diagnostic methods, as CT/MRI, are widely available, the bone scintigraphy still does remain an important tool for imaging bone pathology. An increase in diagnostic accuracy is possible by using different imaging modalities: wholebody scan, three phase bone scintigraphy and SPECT. For this reason, the bone scintigraphy can be used for diagnosis of tumors/infections and therapy monitoring. Applying these methods, important informations can be gained for differential diagnosis. The bone scintigraphy is easy to perform, allows good whole-body overview by low radiation burden to the patient.     

Clinical spectrum and diagnostic pitfalls of multiple abnormal uptakes on bone scintigraphy

Bone scintigraphy with technetium-99m (^99mTc)-labeled diphosphonates is one of the most frequently performed radionuclide procedures. Accumulation of ^99mTc-labeled diphosphonate is well recognized to reflect conditions of accelerated bone turnover and metabolism. Therefore, it is a functional imaging modality for detecting metastatic bone tumors, metabolic bone disease, traumatic injury, and inflammation. This pictorial essay describes the possible patterns of distribution of abnormal uptake for differential diagnosis of metastatic bone tumor, as well as the diagnostic pitfalls of bone scintigraphy.     

Diagnostic value of TI-201 and three-phase bone scintigraphy for bone and soft-tissue tumors

PURPOSE: Although TI-201 is highly sensitive for detecting bone and soft-tissue tumors, its uptake is not specific for malignant lesions. This study assessed the differentiation of malignant and benign lesions and evaluated the sensitivity, specificity, and accuracy of TI-201 imaging and three-phase bone scans. MATERIALS AND METHODS: Forty bone and soft-tissue tumors (16 malignant and 24 benign) were evaluated. TI-201 static images were acquired 10 minutes (early) and 2 hours (delayed) after injection of the radionuclide. Within 14 days, three-phase bone scintigraphy was performed using Tc-99m HMDP with the patient in the same position. The count ratio of the lesion compared with the normal contralateral or adjacent site (L:N ratio) was measured. RESULTS: With TI-201 scintigraphy, mean (+/- SD) values of early and delayed L:N ratios were 3.36 +/- 1.25 and 2.88 +/- 1.20, respectively, in malignant lesions; and 1.88 +/- 1.14 and 1.48 +/- 0.76, respectively, in benign lesions. TI-201 accumulation in benign lesions was significantly less than that of malignancies on early and delayed images. However, an overlap of both ratios between malignant and benign lesions was seen. No such significance was detected on three-phase bone scintigraphy (L:N ratios of malignant and benign tumors were 2.57 +/- 1.22 and 2.24 +/- 2.11, respectively, for blood flow imaging; 2.41 +/- 0.78 and 2.26 +/- 1.54, respectively, for blood pool imaging; and 2.80 +/- 2.10 and 2.89 +/- 4.55, respectively, for bone imaging). When we assumed that the tumor was malignant when the delayed TI-201 L:N ratio exceeded the blood pool phase L:N ratio with bone scintigraphy, the sensitivity rate was 81%, specificity rate was 100%, and accuracy rate was 93%. CONCLUSIONS: TI-201 imaging for bone and soft-tissue tumors was better than three-phase bone scintigraphy alone but was not good enough to clearly differentiate malignant lesions from benign ones. TI-201 scintigraphy, performed in combination with three-phase bone scintigraphy, may be superior to either one of the two imaging procedures alone for bone and soft-tissue tumor diagnosis.     

Radionuclide bone imaging: an illustrative review.

Bone scintigraphy with technetium-99m-labeled diphosphonates is one of the most frequently performed of all radionuclide procedures. Radionuclide bone imaging is not specific, but its excellent sensitivity makes it useful in screening for many pathologic conditions. Moreover, some conditions that are not clearly depicted on anatomic images can be diagnosed with bone scintigraphy. Bone metastases usually appear as multiple foci of increased activity, although they occasionally manifest as areas of decreased uptake. Traumatic processes can often be detected, even when radiographic findings are negative. Most fractures are scintigraphically detectable within 24 hours, although in elderly patients with osteopenia, further imaging at a later time is sometimes indicated. Athletic individuals are prone to musculoskeletal trauma, and radionuclide bone imaging is useful for identifying pathologic conditions such as plantar fasciitis, stress fractures, "shin splints," and spondylolysis, for which radiographs may be nondiagnostic. A combination of focal hyperperfusion, focal hyperemia, and focally increased bone uptake is virtually diagnostic for osteomyelitis in patients with nonviolated bone. Bone scintigraphy is also useful for evaluating disease extent in Paget disease and for localizing avascular necrosis in patients with negative radiographs. Radionuclide bone imaging will likely remain a popular and important imaging modality for years to come.     

Role of whole-body diffusion-weighted MRI in detecting bone metastasis

Purpose

The aim of this study was to compare the results of whole-body diffusion-weighted magnetic resonance (DW-MR) imaging with staging based on computed tomography (CT) and nuclear scintigraphy using Tc99m results as the standard of reference.

Methods and materials

Seventeen patients with known malignant tumours were included in the study. The thorax and the abdomen were imaged using breath-hold diffusion-weighted imaging and T1-weighted imaging sequences in the coronal plane. Location and size of osseous metastases were documented by two experienced radiologists. Whole-body DW-MR imaging findings were compared with results obtained at skeletal scintigraphy and CT bone survey.

Results

The mean examination time for whole-body DW-MR imaging was 25.5 min. All bone metastases regardless of the size were identified with whole-body DW-MR imaging; MR imaging depicted more bone metastases than CT. Skeletal scintigraphy depicted osseous metastases in 13 patients (with greater sensitivity to the lower limb), whereas whole-body DW-MR imaging revealed osseous metastases in 13 patients (with greater sensitivity to the spine). DW-MR did not show good results for detection of rib cage metastases. The additional osseous metastases seen with MR imaging were confirmed at follow-up examinations and some had a change in therapy. MR identified 22 % more metastatic lesions when compared to bone scintigraphy and 119 % when compared to CT. Bone scintigraphy identified 80 % more metastatic lesions when compared to CT. On a per-patient basis, whole-body DW-MR imaging revealed sensitivity and specificity values of 100 %.

Conclusion

Whole-body DW-MR imaging was more sensitive in the detection of osseous metastases than were skeletal scintigraphy and CT bone survey.     

急性骨髓炎的影像学诊断研究进展

急性骨髓炎的影像学诊断技术包括X线平片、超声、CT、MRI及放射性核素显像.早期X线平片的诊断灵敏度低.超声能早期发现深部软组织及骨膜下脓肿,但图像质量取决于操作者的熟练程度.CT能早期观察到微小的骨质改变,但灵敏度较低.MRI可优于其他检查显示髓腔内的病变,但对于死骨、钙化的诊断不如CT灵敏.放射性核素显像剂的种类繁...     

Whole-body bone marrow MRI in patients with metastatic disease to the skeletal system

PURPOSE: The purpose of this study was to evaluate the diagnostic potential of a whole-body bone marrow MR protocol in the detection of bone metastases. METHOD: Whole-body bone marrow MRI was performed in 18 patients with known malignant tumors and suspected bone metastases. The imaging protocol consisted of fast T1-weighted and STIR sequences applied in different anatomical positions covering the whole skeleton. MRI findings indicating bone metastases were compared with findings from bone scintigraphy. Metastatic lesions were confirmed by follow-up MR examinations, bone scintigraphy, radiography, or CT. RESULTS: A total number of 216 lesions were detected with MRI in comparison with 159 lesions detected with bone scintigraphy. Follow-up examinations confirmed 105 lesions. MRI detected 96 (91.4%) of the confirmed lesions, whereas bone scintigraphy detected 89 (84.8%). The entire examination, including patient positioning and changing of imaging coils, required 45 min of room time. CONCLUSION: Whole-body bone marrow MRI as used in this study is an effective method for evaluating the entire skeletal system in patients with suspected metastatic disease.     

Primary musculoskeletal tumors: examination with MR imaging compared with conventional modalities

In 176 cases of primary musculo-skeletal tumors, the informative value of magnetic resonance (MR) imaging was compared with that of plain radiographic examination, angiography, scintigraphy, and computed tomography (CT). In all patients the surgical and histopathologic results were known. For bone tumors confined to the bone, MR imaging was excellent for evaluation of intraosseous extent, but it could not be proved significantly better than CT or scintigraphy. MR imaging was inferior to plain radiography and CT for evaluation of calcification, ossification, cortical destruction, and endosteal/periosteal reaction. For soft-tissue tumors and bone tumors with soft-tissue extension, MR imaging was significantly better than the other modalities in all variables examined: delineation between tumor and muscle, tumor and vessel, tumor and fat, tumor and joint, and tumor and bone, as well as depicting intralesional necrosis and bleeding.     

外周原始神经外胚层肿瘤的 CT及MRI 表现

目的：探讨外周原始神经外胚层肿瘤（pPNET ）的CT 及MRI表现。方法回顾性分析9例经病理证实的pPNET 的CT、MRI表现及病理特点。其中8例行CT平扫和（或）增强扫描;5例行MRI平扫和（或）增强扫描。结果病灶位于头颈部2例,胸部3例,阴囊1例,右肩胛区1例,下肢2例。病灶7例为单发,呈类圆形或不规则形,分叶状,最长径约为1．6～13．8cm,平均6．2cm。8例与周围组织分界不清。CT平扫呈以等密度为主的混杂密度;MRI平扫 T1WI为等稍低信号,T2WI多为不均匀高信号。增强扫描呈多种强化表现,常见为中度以上不均匀强化。其中3例与邻近骨关系密切,表现为溶骨性骨质破坏。结论 pPNET CT及M RI表现缺乏特征性,对临床的定位及定性诊断有一定的帮助。     

Clinical usefulness of 99mTc-PMT whole body scans in the diagnosis of bone metastases from hepatocellular carcinoma]

The diagnostic value of whole body scanning using 99mTc-N-pyridoxylmethyltryptophan (PMT) was evaluated in 16 patients with bone metastases from hepatocellular carcinoma, in comparison with 99mTc-MDP. Of the 72 known lesions of bone metastases, 63 (87.5%) were detected by 99mTc-PMT scintigraphy, which demonstrated increased uptake of radionuclide. However, 99mTc-MDP bone scintigraphy detected only 45 lesions (62.5%), which were shown as increased, decreased, or mixed patterns of uptake. Thus 99mTc-PMT scintigraphy was more sensitive than 99mTc-MDP bone scintigraphy. In addition, the latter showed poor specificity because of its high false positive rate due to degenerative change. All lesions undetected by 99mTc-PMT scintigraphy were located in areas that overlapped the liver or bowel activity. In conclusion, it is recommended that whole body 99mTc-PMT scintigraphy be combined with 99mTc-MDP bone scintigraphy for the detection of bone metastases from hepatocellular carcinoma.     

Fatigue Stress Fractures of the Pubic Ramus in the Army: Imaging Features with Radiographic, Scintigraphic and MR Imaging Findings

Although fatigue fractures are not unusual in athletes and military personnel those of the pubic ramus are rare. We report three cases of fatigue fractures of the inferior pubic rami in two male recruits and one female military cadet. On the initial radiograph, most of the lesions were subtle and easy to overlook. However, bone scintigraphy provided more distinct images that allowed easy and early detection of lesions, and MR imaging presented more diagnostic information, which allowed a precise diagnosis.     

Nuclear medicine in diagnosis and therapy of bone and joint diseases

Concerning bone and joint diseases therapy of rheumatic synovitis (= radiosynoviorthesis) was introduced in 1952 before clinically relevant diagnostic procedures were developed. Radionuclides of Sr and later on 99mTc phosphonates then started the wide use of bone scintigraphy since > 30 years. The diagnostic methods have an excellent sensitivity for detection of local abnormalities of bone metabolism, the specificity of such studies, however, is low. Modifications of the technique (3-phase-bone-scintigraphy, pinhole collimators, ROI-technique), increasing knowledge of pathological scan patterns and introduction of other radionuclide studies (67Ga, 201Tl, inflammation scans with 99mTc-leukocytes or 99mTc-HIG) as well as 18FDG-PET have increased the specificity significantly in recent years and improvements of imaging systems (SPECT) also increased the accuracy of diagnostic methods in diseases of bone and joints. Therapy of such diseases has made considerable progress: inflamed, swollen joints can effectively be treated with 90Y-, 186Re, 169Er-colloids or with 165Dy-particles by radiosynoviorthesis. Severe pain due to disseminated bone metastases of cancer or polyarthritis can be controlled by radionuclide therapy with 89Sr, 153Sm-EDTMP, 186Re- or 188Re-HEDP and possibly 117mSn-DTPA with an acceptable risk of myelodepression. Possibilities, technical details and limitations of radionuclide applications for diagnostic and therapeutic purposes must be considered if optimal benefit for individual patients should be achieved. Overall Nuclear Medicine can become an essential element in management of bone and joint diseases. The relationship of Nuclear Medicine to bone and joint pathology is peculiar: In 1952 treatment of rheumatic synovitis by radiosynoviorthesis with 198Au Colloid was started by Fellinger and Schmid before diagnostic approaches to bone pathology existed. Bone scintigraphy was introduced only in 1961 using 85Sr but obviously the unfavourable radiation characteristics of this radionuclide limited it's broad application and 87mSr did not improve this situation. Only when 99mTc phosphonates were developed by Subramanian the importance of bone scintigraphy became apparent: The excellent imaging properties of these radiotracers showed, that abnormal bone metabolism could be visualized even before morphological alterations in the skeleton become visible on radiographies or even CT-scans. Moreover, proposals made earlier to use 32P or 89Sr for palliation of pain in patients with disseminated skeletal metastases were picked up again and led also to other radiopharmaceuticals (186Re-HEDP, 153Sm-EDTMP, 117mSn-DTPA) which are applied today for the same purpose with very good success. Therefore Nuclear Medicine today has a broad program for diagnostic and therapeutic approaches to diseases of bone and joints. In bone scanning the high sensitivity led to inclusion of this method for routine staging and re-staging programs in a variety of cancer forms which have a trend to develop bone metastases (e.g. breast, lung, prostate, melanoma) but the low specificity of abnormal patterns on such scans can impair the diagnostic value of the technique. To increase specificity and to define inflammatory lesions, radiotracers used for "inflammation scanning" were introduced such as labeled granulocytes, 99mTc Human Immunoglobulin and others but also a simple modification of bone scanning--triple phase bone scintigraphy--was used. Recently the excellent properties of 18F for PET of the skeleton were rediscovered again and emission CT scanning--possibly with overlay with transmission CT or MRT pictures--can enhance the diagnostic impact of radionuclide bone studies.     

Osteosarcoma. A new diagnostic approach in presurgical loco-regional staging

The value of Magnetic Resonance (MR) imaging was examined in the anatomical staging of bone osteosarcomas. Eleven patients were studied--8 central and 3 parosteal osteosarcomas. The accuracy of MR imaging was compared to that of plain film, scintigraphy, CT, and angiography. MR imaging was superior to both CT and radionuclide scanning in defining intramedullary extension and in showing skip metastases. Cortical erosion in central osteosarcomas was demonstrated by MR imaging, CT, and plain film; in 1 case of parosteal osteosarcoma MR imaging was superior to CT in showing cortical penetration. In two cases MR imaging did not accurately demonstrate the relationship of the tumor to the major vessels; only angiography showed vascular involvement. MR imaging was useful in delineating extraosseous extension. The importance is stressed of a correct use of MR imaging towards an accurate diagnosis. In fact, intramedullary extension and skip metastases were better demonstrated on T1-weighted images with large fields, while T2-weighted images and small fields were needed for the best overall evaluation of extraosseous involvement. In conclusion, MR imaging should be used for preoperative staging of osteosarcomas in those cases where diagnosis was made on the basis of clinical, radiographic, and bioptic findings.     

Characterization of orbital lesions by surface coil MR imaging

Surface coil MR imaging is an effective technique for evaluating orbital pathology. T1 and T2 weighting provides information not obtainable by CT and results in better characterization of some lesions. MR appears to be most useful for characterizing ocular pathology, specifically for differentiating retinoblastoma from benign diseases (Coat's disease and PHPV). MR can also be used to separate ocular tumors from associated subretinal fluid. With MR imaging, the signal intensities of lymphoma differ from those of benign inflammatory or infiltrative conditions such as pseudotumor or thyroid ophthalmopathy. Mucoceles, too, have a specific signal intensity pattern with T1 and T2 weighting. CT appears to be superior to MR for demonstrating densely calcified lesions or lesions of bone.     

Three-phase radionuclide bone imaging and magnetic resonance imaging detection of occult knee fractures in athletes

Twelve athletes presenting acute knee injury with normal radiological findings underwent both three-phase radionuclide bone imaging (TPBI) and magnetic resonance imaging (MRI). The association of these highly sensitive diagnostic procedures detected occult fractures in all patients. The areas of signal intensity alterations on MRI corresponded to those of increased radionuclide uptake in blood pool images. However, the same areas seemed to be more extended on delayed TPB images. TPBI yielded early diagnostic information about lesion sites and functional activities, while MRI provided better anatomical definition and specific information about associated soft tissue lesions and served to establish the correct therapeutic approach and follow-up. Correspondence to: I. Baschieri     

Scientigraphic hot lesions secondary to osseous metastases in a patient with multiple myeloma

The myeloma bone deposits may be normal or may also appear as areas of a low uptake on the bone scintigraphy; the presence of multiple hot lesions with negative X-ray and minimal CT findings in patients with multiple myeloma being very uncommon. We reported the case of a 68 year old woman suffering from a multiple myeloma with multiple and hot metastatic lesions in bone scintigraphy. The X-ray was negative and the CT-findings only demonstrated a lytic femoral lesion, the spinal osseous dissemination being confirmed by MRI. We believe that this is an interesting work due to the rarity of the scintigraphic pattern as well as the discussion carried out on the radionuclide imaging methods in the diagnosis of myeloma-related bone lesions.     

Imaging of abdominal neuroblastoma in children.

PURPOSE: The aims of the study were: 1) to assess the efficacy of different imaging methods for use prior to treatment; 2) to compare the surgico-histopathologically-based International Neuroblastoma Staging System (INSS) staging with the imaging results; and 3) to suggest a localisation scheme for abdominal neuroblastoma. MATERIAL AND METHODS: Thirty-one children with an abdominal neuroblastoma (median age 2 years), underwent abdominal US, CT of chest and abdomen, MR imaging of abdomen and spine, chest radiography, skeletal survey, radionuclide bone scintigraphy, MIBG scintigraphy, and bone marrow biopsy. RESULTS: In the evaluation of local disease, CT and MR were superior to US. There was no significant difference between CT and MR in assessment of the location or size of the tumour. Evaluation of invasive growth and lymphadenopathy was uncertain irrespective of imaging modality. Intraspinal extension was more distinctly demonstrated with MR. Tissue characterization with CT and MR did not contribute in the assessment of the tumours. Contrast enhancement at CT and MR examinations both improved demarcation between tumour and kidney, and was a necessity for evaluation of vessel encasement with CT. The local disease was best assessed by either CT or MR, while metastatic disease was best revealed by CT, MR, scintigraphy or bone marrow biopsy. CONCLUSION: Imaging may be a valuable basis for clinical assessment and pretreatment staging of abdominal neuroblastoma.