The value of bone scintigraphy,bone marrow scintigraphy and fast spin-echo magnetic resonance imaging in staging of patients with malignant solid tumours: a prospective study

The purpose of this prospective study was to define the value of bone scintigraphy (BS), bone marrow scintigraphy (BMS) and the new fast spin-echo (FSE) magnetic resonance imaging (MRI) sequences in screening for bone metastases in patients with solid malignant tumours. It was our particular interest to classify patients into a group with and a group without bone metastases, and not only to compare the absolute number of metastases detected by each method. Thirty-two patients were examined using technetium-99m dicarboxy propane diphosphonate bone scintigraphy, ^99mTc-labelled monoclonal anti-granulocyte antibodies for bone marrow scintigraphy and 1.5 T MRI using T1-weighted and FSE T2-weighted sequences. Against a reference standard obtained by re-evaluation of all clinical and imaging data 1 year after prospective BS, BMS and MRI had been performed, the three imaging modalities were falsely positive in two, eight and two cases and falsely negative in zero and four cases, respectively. BMS was falsely positive in eight patients because of vertebral marrow degeneration which caused photopenic defects which could not be differentiated from metastases. MRI showed these lesions to unequivocally contain fat. BMS and MRI were falsely negative in four cases because of the limited field of examination. In our study the key factor in classifying a patient as bone MI or MO was the possibility of surveying the entire skeleton, as is the case in BS, and not that MRI had a higher sensitivity compared to BS when analysis was on a lesion-by-lesion basis. BMS had the same limitations as MRI because the usual bone marrow distribution resulted in a physiologically limited field of view. We conclude that BS remains the method of choice in staging patients with solid tumours despite the fact that MRI is no longer a time-consuming method using FSE sequences. MRI has a complemantary role if special questions remain. BMS appears to have little value in the detection of bone metastases because of its poor specificity, its limited spatial resolution and its restriction to those areas of the skeleton containing haematopoietic marrow. Correspondence to: G.K. v. Schulthess     

Magnetic resonance imaging and magnetic resonance spectroscopy of bone tumors and bone marrow disease

The authors have made use of an integrated magnetic resonance imaging/spectroscopy (MRI/MRS) examination to study seven patients with a variety of bone tumors. The spatial localization method used in the 31P portion of the examination was surface coil localization and a one-dimensional chemical shift imaging method (3 cases). The authors found that the precision of spatial localization was critical in many of these cases, since most of these bone tumors were surrounded by muscle tissue that contained high concentrations of phosphocreatine (PCr). For this reason, they suggest that the metabolite ratios should be referenced to the adenosine triphosphate (beta-NTP) resonance rather than PCr. The phosphate monoester (PME) to beta-NTP ratio was elevated as compared with normal muscle in all of the bone tumors studied. The authors found that all of these tumors exhibited pHs between 7.0 and 7.2, which are similar to the values found for normal muscle. They also show the feasibility of using a line-selective proton chemical shift imaging sequence with high spatial resolution for investigating changes in the fatty composition of bone marrow. This method is illustrated in an example of a patient with advanced avascular necrosis in the femoral heads.     

放射性核素骨显像在脊柱转移瘤诊断中的价值

脊柱转移瘤(MST)可发生于原发恶性肿瘤临床的各个阶段,传统X线片发现时多为中晚期病变;CT容易漏诊,不能直接显示脊髓的异常;MRI耗时长,病痛的患者不易配合,影响图像的质量.常规骨扫描能够对整个骨骼进行扫描,但特异性不高.核素SPECT骨显像可提高对MST诊断的敏感性和特异性,提示病灶累及的解剖结构或分布形态,并能定...     

Negative scintigraphy with positive magnetic resonance imaging in bone metastases

We report three patients with known primary tumor in whom radionuclide skeletal imaging for metastatic disease was normal with or without clinical symptomatology referable to this area. Magnetic resonance imaging (MRI) of the spine demonstrated focal areas of abnormal signal intensity in the vertebral bodies of these patients. In all three patients, biopsy confirmed metastatic disease. All the patients received radiation or chemotherapy depending upon the etiology. These preliminary data suggest that MR imaging may be useful in evaluating patients with known primary tumor in whom clinical suspicion persists despite a negative radionuclide bone scan.     

Comparative detectability of bone metastases and impact on therapy of magnetic resonance imaging and bone scintigraphy in patients with breast cancer.

OBJECTIVE: to evaluate the comparative impact of magnetic resonance imaging and bone scintigraphy in bone metastases of breast cancer. METHODS AND PATIENTS: in 81 patients with histologically proven breast cancer magnetic resonance imaging of the axial skeleton and whole-body bone scintigraphy had been performed. Images were retrospectively reviewed and compared for detection of metastases, extent of metastatic disease and therapeutic implications according to the patients' records. RESULTS: about 54/81 (67%) patients revealed bone metastases. In 7/54 (13%) patients with bone metastases, scintigraphy was false negative. In one patient a solitary sternal metastases was seen. In 26/53 [49%] patients with spinal metastases, magnetic resonance imaging showed more extensive disease. Local radiotherapy or surgery was indicated in ten patients with metastases not evident in bone scintigraphy, in 20 patients with positive results by both imaging modalities and in six patients with metastases of pelvis imaged by bone scintigraphy only. CONCLUSION: magnetic resonance imaging of the axial skeleton and pelvis appears superior for staging as only one patient had metastases merely outside the axial skeleton and local therapy was indicated even in spinal regions negative in bone scintigraphy.     

Contrast-enhanced magnetic resonance imaging of bone marrow

In the assessment with magnetic resonance (MR) imaging of bone marrow disorders, the use of contrast agents is usually not critical because T1-weighted spin-echo and fat-suppressed sequences (STIR or fat-sat intermediate weighted) are robust and largely available techniques for depiction of neoplastic and non-neoplastic lesions of the bone marrow. This article discusses the characteristics of dynamic contrast-enhanced MR imaging of bone marrow edema, ischemia, and neoplasm. It emphasizes its value in staging and in monitoring of response to chemotherapy of several bone tumors. These fast dynamic contrast-enhanced techniques do not allow differentiation between benign and malignant primary osseous tumors because the biologic behavior rather than the malignant potential of these lesions is reflected.     

Diffusion-weighted magnetic resonance imaging of spinal bone marrow

Diffusion-weighted (DW) imaging is an alternative source of image contrast. DW imaging enables to measure the random motion of free water protons on a molecular basis by using different imaging sequences including steady-state free precession imaging, navigated spin-echo DW imaging, and single-shot echo planar imaging. Analysis of intravoxel incoherent motion of water protons is a promising tool that has shown to be of value in the differential diagnosis between benign and malignant spontaneous vertebral fractures. Acute benign osteoporotic fractures show hypo- or isointense signal on DW sequences that reflects persistent free water proton mobility. With increasing diffusion strength a substantial signal loss is found. Metastatic fractures show hyperintensity compared with normal surrounding bone marrow probably due to altered water proton mobility within neoplasm. The ability of the different methods for DW imaging to differentiate other bone marrow alterations needs to be investigated in further studies.     

Whole-body magnetic resonance imaging for detecting bone metastases: comparison with bone scintigraphy

Purpose

The aim of the study was to assess the reliability of whole-body magnetic resonance imaging (WB-MRI) in detecting skeletal metastasis and to compare the results with those of bone scintigraphy (BS).

Materials and methods

Thirty-three patients (21 women, 12 men, median age 58 years, range 27–78) were enrolled. Histological proof of malignancy was obtained in all cases. The primary tumour was unknown in 1 patient. BS and WB-MRI were performed as staging procedures in 15 patients, during the follow-up in 6 and to investigate pain in 9 and neurological symptoms in 3. Bone metastases were recorded for 8 different skeletal segments (ribs, skull, cervicothoracic spine, lumbosacral spine, clavicle-scapula-sternum, pelvis, upper extremities and lower extremities) in all patients, for a total of 264 examined areas.

Results

Bone metastases were detected in 18 patients (55%). In 15/33 patients, WB-MRI and BS were concordantly negative. BS revealed focal metastatic uptake in 72%, whereas WB-MRI was positive in 89%. Results differed in seven patients. WB-MRI was positive but BS was negative in five cases. Two patients with negative WB-MRI had focal and intense uptake in the ribs on BS. Out of 264 examined areas, bone metastases were detected in 34 (13%). WB-MRI revealed tumour spread in 26/34 areas (76%) and BS in 21/34 areas only (62%).

Conclusions

WB-MRI is a reliable method for screening patients with suspected skeletal metastases, although BS still remains a useful tool. WB-MRI is also advantageous because it reveals extraskeletal and soft tissue metastases.     

Classification and detection of bone marrow lesions with magnetic resonance imaging

A logical approach to bone marrow alterations is proposed that takes into account the high sensitivity and specificity of MR imaging for the detection of marrow fat. Marrow signal intensity on T1-weighted images is assumed to reflect the balance between fat and nonfat marrow components. Elementary patterns of marrow change include marrow depletion, infiltration, replacement and signal void. These patterns can be observed alone or in combination, and can be distributed in a focal or diffuse manner. Marrow depletion pattern shows high signal intensity reflecting increase in fat content and is frequently irrelevant clinically. Signal intensity is decreased in marrow infiltration, replacement and signal void patterns, which indicates partial or complete disappearance of fat. Focal marrow infiltration is frequently reactive to an adjacent abnormality, whereas focal marrow replacement more frequently indicates a more profound marrow alteration. The T1-weighted spin-echo sequence is satisfactory for lesion detection by virtue of its relatively high sensitivity in the detection of alterated fat/nonfat marrow balance. T2-weighted sequences with saturation of the signal of fat protons or out-of-phase gradient-echo sequences improve lesion conspicuity in all situations in which the difference in fat/nonfat marrow balance between the abnormal area and the adjacent normal marrow is reduced.     

The diagnostic value of diffusion-weighted magnetic resonance imaging in characterization of musculoskeletal soft tissue tumors

Purpose

To assess the utility of diffusion-weighted (DW) images and magnetic resonance imaging (MRI) in the detection and characterization of musculoskeletal soft tissue tumours (STTs) and in the determination of whether these tumours are benign or malignant.

The diagnostic value of bone scintigraphy in patients with low back pain

Bone scintigraphy has been studied in two groups of patients presenting with low back pain. In one group of 38 patients suffering "nonspecific" back pain, bone scintigraphy and laboratory findings were negative in 24. There were abnormal laboratory findings in all of the remaining 14 and 7 had positive bone scans indicative of clinically significant disease. Selection of patients for bone scintigraphy in this group should therefore be influenced by abnormal laboratory findings and elevation of the erythrocyte sedimentation rate in particular. By comparison, the bone scans were reviewed from another group of patients suffering previously known malignancy. Out of 138 patients, nearly 40% showed a positive bone scan due to subsequently proven metastasis. Bone scintigraphy was positive in a further 14% as a result of osteoporotic rib fracture and vertebral body collapse. In half of these, it was not possible to exclude malignancy by scintigraphy. The present findings indicate that bone scintigraphy is not a useful procedure in patients with long-standing low back pain who have normal radiographs and normal laboratory findings.     

糖尿病足的MRI诊断价值

目的:探讨糖尿病足的MRI诊断价值.方法:回顾性分析经临床综合诊断证实的12例糖尿病足患者的MRI表现,对病变部位、软组织病变、骨关节病变进行评估.结果:大部分病变位于前足(9/12,占75.0％)和中足(4/12,占33.3％);12例患者均可见软组织肿胀、窦道形成、骨髓水肿及骨髓炎,部分伴脓肿形成(5/12,占41.7％);2例夏科氏关节伴骨髓炎并可见关节脱位及摇椅足形成.结论:MRI能够清楚地显示糖尿病足的骨关节及软组织病变情况,为临床诊疗提供良好的影像依据.     

Nuclear magnetic resonance imaging of bone marrow in childhood leukaemia

Bone marrow infarction is known to occur in childhood leukaemia. Although it may be suspected on clinical grounds, radiographic evidence is infrequent. We present three cases in which magnetic resonance imaging demonstrated unexpectedly extensive bone marrow lesions and discuss the evidence that these lesions were due to bone marrow infarction.     

Roles of magnetic resonance imaging in management of bone tumors

The roles of magnetic resonance imaging (MRI) in the diagnosis and treatment of bone tumors are reviewed. Most bone tumors can be detected on plain radiography or bone scintigraphy. MRI is helpful in detecting tumors that do not destroy bone matrix or suppress reactive bone formation. Detailed analysis by plain radiography is still the most reliable method for differentiating between benign and malignant bone tumors. The T1 and T2 values, internal texture, and peritumoral edema depicted on MRI are not helpful for this differentiation. In characterizing the histologic types of bone tumors, MRI is of some advantage. For example, MRI can demonstrate cartilage matrix, hemoglobin metabolites, vascular components, and fat contents more clearly than conventional radiological techniques. MRI is now indispensable for the preoperative delineation of malignant bone tumors, because of its excellent soft tissue contrast and multiplanar imaging capability. In this article, the guidelines for evaluation of the surgical margin advocated by the JOA Musculo-skeletal Tumor Committee are introduced for radiologists. MRI monitoring of malignant bone tumors after chemotherapy or surgery can reveal change in the size of enhanced areas that may reflect viable tumors. Dynamic MRI is helpful to differentiate recurrent tumors from granulation tissue.     

肺动脉血栓栓塞的MRI诊断价值

目的探讨肺动脉血栓栓塞（ＰＥ）ＭＲＩ诊断的价值和限度。方法２８例患者［男１７例,女１１例,平均（４１．１±１５．６）岁］行ＭＲＩ检查,其中急性期７例,慢性期２１例。应用心电图门控自旋回波（ＳＥ）、梯度回波（ＧＲＥ）和时间飞跃（ＴＯＦ）法二维ＭＲ血管造影（ＭＲＡ）技术。结果２４例中心型ＰＥ患者在扩张的肺动脉内显示栓子：Ｔ１ＷＩ呈中等信号或中等度高信号,Ｔ２ＷＩ均呈高信号,ＧＲＥ电影ＭＲＩ显示栓子呈中等或低信号,ＭＲＡ可见肺动脉内不规则形、中等信号的充盈缺损。４例周边型ＰＥ患者,ＭＲＩ显示肺内靠近胸膜处有斑片状异常信号。ＰＥ的继发异常征象有：右心室扩大、室壁运动减弱,伴三尖瓣返流,室间隔僵直,凸向左心室侧,左心房室缩小,主肺动脉显著扩张等。慢性期患者右心室壁均明显增厚,达（８．０±１．７）ｍｍ,而急性期无此改变。结论ＭＲＩ可准确作出中心型ＰＥ的诊断,但是周围型ＭＲＩ所见与慢性阻塞性肺心病难以鉴别,为ＭＲＩ的不足之处。     

腰椎轴向负荷MRI对腰椎退行性疾病诊断的影响

目的 评估仰卧位轴向负荷MRI对腰椎退行性疾病诊断的影响.方法 对30名健康志愿者及89例腰腿痛患者进行了常规仰卧腰大肌放松体位(PRP)和仰卧位轴向负荷(ACE)MRI.89例腰腿痛患者中慢性下腰痛61例,坐骨神经痛19例,神经性跛行9例.观察、分析下腰椎(L3～4、L4～5、15～S1水平)椎管变化情况.结果 30名志愿者90个椎间盘水平ACE检查发现10名(33.3%)共14个椎间盘水平(15.6%)硬膜囊横截面积(DSCA)缩小15 mm2以上.89例患者267个椎间盘水平ACE检查发现38例(42.7%)55个椎间盘水平(20.6%)DSCA缩小15 mm2以上(平均缩小28 mm2).89例患者中ACE检查还发现有26例32个椎间盘突出程度加重,12例16个椎间盘水平椎间孔狭窄,10例11个水平黄韧带增厚,3例3个水平小关节半脱位,3例3个水平椎体滑脱.89例患者中22例(24.7%)ACE检查提供了更多的有效信息,其中7例(7/9)神经性跛行患者、8例(8/19)坐骨神经痛患者及11.5%(7/61)下腰痛患者ACE检查提供了有效信息.结论 与常规检查方法比较,ACEMRI能提供附加有效信息,能发现更多的隐匿性病变,对诊断腰椎退行性病变具有重要意义.     

Normal age-related patterns of cellular and fatty bone marrow distribution in the axial skeleton: MR imaging study

Knowledge of age-related distribution patterns of cellular and fatty marrow is critical to the interpretation of magnetic resonance (MR) imaging studies. To determine such patterns, the authors retrospectively evaluated 70 examinations each of the skull, cervical spine, thoracic spine, lumbar spine, pelvis, and proximal femur (420 examinations) in patients without known bone marrow abnormality who ranged in age from 6 months to older than 70 years. Two to four distinct patterns were identified in each anatomic area on spin-echo images obtained with a short repetition time and a short echo time. The relative frequency of the patterns for different age groups is consistent with the known physiologic conversion from cellular to fatty marrow with advancing age. Knowledge of these patterns should help in the interpretation of MR images of the axial skeleton.     

Clinical relevance of diffusion and perfusion magnetic resonance imaging in assessing intra-axial brain tumors

Advanced magnetic resonance (MR) imaging techniques provide physiologic information that complements the anatomic information available from conventional MR imaging. We evaluated the roles of diffusion and perfusion imaging for the assessment of grade and type of histologically proven intraaxial brain tumors. A total of 28 patients with intraaxial brain tumors underwent conventional MR imaging (T2- and T1-weighted sequences after gadobenate dimeglumine injection), diffusion imaging and T2*-weighted echo-planar perfusion imaging. Examinations were performed on 19 patients during initial diagnosis and on nine patients during follow-up therapy. Determinations of relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC) were performed in the solid parts of each tumor, peritumoral region and contralateral white matter. For gliomas, rCBV values were greater in high-grade than in low-grade tumors (3.87±1.94 versus 1.30±0.42) at the time of initial diagnosis. rCBV values were increased in all recurrent tumors, except in one patient who presented with a combination of recurrent glioblastoma and massive radionecrosis on histology. Low-grade gliomas had low rCBV even in the presence of contrast medium enhancement. Differentiation between high- and low-grade gliomas was not possible using diffusion-weighted images and ADC values alone. In the peritumoral areas of untreated high-grade gliomas and metastases, the mean rCBV values were higher for high-grade gliomas (1.7±0.37) than for metastases (0.54±0.18) while the mean ADC values were higher for metastases. The rCBV values of four lymphomas were low and the signal intensity–time curves revealed a significant increase in signal intensity after the first pass of gadobenate dimeglumine. Diffusion and perfusion imaging, even with relatively short imaging and data processing times, provide important information for lesion characterization.