Imaging of primary multifocal osseous lymphoma

 Objective. To review our experience with primary multifocal osseous lymphoma (PMOL), to characterize its imaging features, before and after treatment, and to correlate these features with clinical outcome. Design. Hospital charts and imaging studies of eight patients with PMOL were reviewed. These included bone radiographs, bone scans, CT and MRI. Number, distribution and appearance of lesions before treatment were evaluated; and post-treatment changes were assessed for evidence of healing or progression, correlated with clinical outcome. Results. A total of 63 lesions were identified by pre-treatment bone scan, 36 by MRI (including 10 not visible on bone scan) and 16 by radiographs. Twenty-one percent of lesions occurred about the knee, and 63% of patients had concomitant skull, distal femoral and proximal tibial lesions. The radiographic appearance ranged from lytic to sclerotic. Lesions were isointense to hematopoietic marrow on T2-weighted MR sequences. Only plain radiographic evidence of healing or progression correlated with clinical outcome. Conclusion. Distribution of PMOL was best assessed by bone scan. However, MRI revealed larger areas of marrow involvement and detected lesions in the pelvis not seen on bone scan. Marrow involvement around the knee was common, and the combination of skull, distal femoral and proximal tibial lesions may suggest the diagnosis. Radiographs underestimate the extent of disease but were the best modality for assessment of treatment response.     

MR imaging of diffuse bone marrow replacement in pediatric patients with cancer

In the magnetic resonance (MR) imaging examinations of three children with tumors (two neuroblastoma, one rhabdomyosarcoma) and three with leukemia, the marrow demonstrated a diffuse, uniform pattern of hypointensity on T1-weighted images and hyperintensity on T2-weighted images. The authors observed that this reversal ("flip-flop") of the usual MR characteristics of fatty marrow was seen in the epiphyses, metaphyses, and diaphyses. The purpose of this study was to establish the radiographic and clinicopathologic correlates of this MR finding on the basis of findings from plain radiographs, bone scans, and bone marrow aspirates. Plain radiographs and bone scans demonstrated either normal findings or changes limited to the metaphyses. In all patients, analysis of bone marrow aspirates demonstrated metastases. The authors concluded that even in the absence of evidence of discrete bone metastases on a plain radiograph or a bone scan, this diffuse and uniform "flip-flop" pattern reflects diffuse marrow replacement by tumor cells.     

Chronic lymphocytic leukemia: Changes in bone marrow composition and distribution assessed with quantitative MRI

The purposes of this study were (α) to determine the prevalence of bone marrow abnormalities in patients with chronic lymphocytic leukemia (CLL) using quantitative MR assessment of axial marrow composition and peripheral marrow distribution; (b) to assess the agreement between both quantitative MR methods and compare their sensitivities to detect marrow alterations; and (c) to correlate MR findings with clinical and laboratory parameters. Twenty-nine consecutive patients with biopsy-proven CLL were investigated on a .5-T MR imager to determine bulk T1 relaxation times of the vertebral bone marrow and proportion of proximal femur surface area occupied by nonfatty marrow on coronal T1-weighted MR images of one hip. Of the 29 patients, 12 (41%) had abnormal increase in lumbar marrow T1 values (>600 msec) and 16 (55%) had increased proportion of surface area occupied by non-fatty marrow in the proximal femur (>+1 SD compared to normal values determined in sex- and age-matched healthy subjects). The results of both quantitative MR methods were normal in 12 patients and abnormal in 11 patients (agreement, 79%). Patients with alterations in peripheral marrow distribution had significantly higher T1 relaxation times (P = .001) than those with normal peripheral marrow. Patients with abnormal marrow composition or distribution at MRI had significantly higher blood and marrow lymphocytosis than patients without these features. In conclusion, the agreement between both quantitative MR methods suggests a parallelism between changes in axial marrow composition and in peripheral marrow distribution in patients with CLL. The limits of quantitative MRI in CLL must be kept in mind, because quantitative MR methods failed to detect leukemic marrow infiltration in 41% of patients.     

The application of MR imaging in the detection of hip involvement in patients with ankylosing spondylitis

Objective

To investigate the changes in hip MR imaging, evaluate the frequency of hip involvement and compare the value of clinical symptoms, radiographs, and MR imaging in the detection of hip involvement in patients with ankylosing spondylitis (AS).

Methods

Anteroposterior radiographs of the pelvis, MR imaging of the hip and clinical evaluation were undertaken in 58 patients with definite AS. All patients were followed up 3 years. Annual radiographs and clinical evaluation were carried out. The imaging data were independently assessed by two experienced radiologists who were blinded to patient identity and clinical characteristics. Based on the Bath Ankylosing Spondylitis Radiology Hip Index (BASRI-hip) scoring system, BASRI-hip scores ≥2 were defined as radiological hip involvement. On MR imaging, both acute and chronic inflammatory changes were considered positive signs for hip involvement. Symptomatic hip involvement was defined as current or past pain or limitation of the hip movement. The statistical analysis was performed using the χ² test for comparison of sensitivity among clinical symptoms, radiographs, and MR imaging in the detection of hip involvement and the Student's t-test for comparison of disease duration between with and without hip involvement. A P value <0.05 was considered to be statistically significant. For interpreting MRI and radiographs, the percentage of agreement between the two assessors and the kappa coefficients were calculated.

Results

On MR imaging, positive changes were detected in 86 (74.1%) hips among 116 hips in all 58 patients. Joint effusion was observed in 73 (62.9%) hips; 23 out of 27 patients who underwent fat-saturated contrast-enhanced T₁-weighted sequences had abnormal synovial enhancement in bilateral hips. The other abnormal MR findings included subchondral bone marrow edema in 35 (30.2%) hips, enthesitis in 22 (19.0%) hips, fatty accumulation of the bone marrow in 28 (24.1%) hips, bone erosive destruction in 32 (27.6%) hips, and joint-space narrowing in 4 (3.4%) hips. Based on the BASRI-hip scoring system, 68, 24, 18, 6 and 0 hips had no, suspicious, mild, moderate or severe damage on conventional radiographs of the pelvis, respectively. Thirty-five hips in 20 patients had current or past pain or limitation. The proportion of hip involvement according to MR imaging, radiographs, and clinical symptoms was 74.1% (86/116), 20.7% (24/116), and 30.2% (35/116), respectively. MR imaging yielded higher values than radiographs and clinical symptoms in the detection of hip involvement in patients with AS (χ² = 66.45 and 44.93, P <0.05). Interreader reliability for interpretation of findings was acceptable for both MRI and radiographs. During follow-up, radiological hip involvement were found in 10 hips with BASRI-hip scores ≤1 at baseline and clinical symptoms appeared in 15 sides of the original asymptomatic hip. On baseline MR imaging, inflammatory changes were seen in all hips which appeared symptoms and/or radiological involvement both at baseline and during follow-up.

Conclusion

The proportion of hip involvement is much higher than that suggested by radiographic changes and clinical symptoms. MR imaging is superior to conventional radiographs and clinical symptoms in the detection of hip involvement. Joint effusion and synovial enhancement caused by synovitis are the commonest hip findings on MR imaging in patients with AS.     

Thoracic outlet syndrome: evaluation with CT

Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs.     

Systemic mastocytosis: MRI of bone marrow involvement

Systemic mastocytosis (SM) is an abnormal proliferation of mast cells, located in different structures: skin, bone marrow, spleen, liver and lymph nodes. Magnetic resonance imaging was prospectively performed in ten patients diagnosed by bone marrow biopsy in order to describe the different patterns of bone marrow involvement. Coronal T1-weighted spin-echo images were obtained in vertebral, pelvic, humeral and femoral bones. Depending on the extension of the cell infiltration, three patterns of bone marrow involvement were used: normal/no involvement (N), non-homogeneous (NH) and homogeneous (H). All ten patients presented bone infiltration. The patterns observed were: spine (50 % NH, 50 % H), pelvis (70 % NH), humerus 100(NH) and femur 40 % (NH). T1-weighted MR imaging is a sensitive technique for detecting marrow abnormalities in patients with systemic mastocytosis. There is no correlation between percentage of mast cells in bone marrow biopsy and extent or pattern of bone marrow involvement. Received: 5 June 1998; Revision received: 23 November 1998; Accepted: 15 January 1999     

Tarsal navicular relations in club foot: is there a role for magnetic resonance imaging?

Objective. To correlate radiographic and MR appearances with surgical findings to determine the accuracy of these modalities in demonstrating tarsal navicular (TN) relations in order to select the appropriate surgical intervention. Design and patients. Fourteen consecutive patients with 19 club feet had anteroposterior and lateral radiographs and magnetic resonance (MR) imaging performed. Blinded retrospective interpretation of these studies was correlated with surgical findings. Movement artifact was responsible for initial non-diagnostic MR scans in 3 out of 19 feet. Results. Plain radiographs and MR imaging had sensitivities of 79% and 84% respectively for TN subluxation, while both modalities had 100% positive predictive value for TN subluxation. Each modality produced indeterminate results in cases where subluxation was present at surgery, but in combination there were no false negatives. Conclusion. Radiography confidently predicted the TN alignment in the majority of cases. MR demonstrated TN relationships in all cases where radiography was indeterminate. It is proposed that MR has a potential role to demonstrate TN relationships when radiography is indeterminate or when there is disparity between the clinical and radiographic assessment.     

Nuclear medicine studies in evaluation of skeletal lesions in children with histiocytosis X

Radiographs were compared with 99mTc scans of the bones and bone marrow as well as 67Ga-citrate scans to evaluate their sensitivity in identifying skeletal lesions in 21 children with histiocytosis X. Seven of 20 bone scans were completely normal in patients with extensive radiographic evidence of skeletal disease. In only one patient were bone scan changes demonstrated prior to radiographic abnormalities. None of the lesions was "cold" on the bone scans. 99mTc-sulfur colloid bone marrow scans and 67Ga-citrate whole-body scans were not valuable. Radiographic survey of the skeleton should be the primary diagnostic test employed in patients with histiocytosis X who have suspected skeletal lesions. Bone scans should be obtained only when the radiographs are normal or equivocal.     

MRI findings of juvenile psoriatic arthritis

Objective  The aim of this study was to describe the magnetic resonance imaging (MRI) features of juvenile psoriatic arthritis (JpsA) in children in order to facilitate early diagnosis and proper management. Materials and methods  Two pediatric radiologists retrospectively reviewed in consensus a total of 37 abnormal MRI examinations from 31 pediatric patients (nine boys, 22 girls; age range 1–17 years; mean age 9.4 years) who had a definite diagnosis of JpsA and underwent MRI. Each MRI was evaluated for synovium abnormality (thickening and enhancement), joint effusion (small, moderate, and large), bone marrow abnormality (edema, enhancement, and location of abnormality), soft tissue abnormality (edema, enhancement, atrophy, and fatty infiltration), tendon abnormality (thickening, edema, tendon sheath fluid, and enhancement), and articular abnormality (joint space narrowing and erosion). The distribution of abnormal MRI findings among the six categories for the 37 MRI examinations was evaluated. The number of abnormal MRI findings for each MRI examination was assessed. Age at MRI examination and all six categories of abnormal MRI findings according to gender were evaluated. Results  There were a total 96 abnormal MRI findings noted on 37 abnormal MRI examinations from 31 pediatric patients. The 37 abnormal MRI examinations included MRI of the hand (n = 8), knee (n = 8), ankle (n = 5), pelvis (n = 5), temporomandibular joint (n = 4), wrist (n = 3), foot (n = 2), elbow (n = 1), and shoulder (n = 1). Twenty-eight diffuse synovial thickening and/or enhancement were the most common MRI abnormality (29.2%). Joint effusion comprised 22 abnormal MRI findings (22.9%). There were 16 abnormal MRI bone marrow edema and/or enhancement findings (16.7%), and in seven (7.3%) the edema involved non-articular sites. Soft tissue abnormality manifested as edema and/or enhancement constituted 14 abnormal MRI findings (14.5%). There were ten MRI abnormalities (10.4%) involving tendons. Articular abnormality seen as joint space narrowing and/or bone erosion comprised six abnormal MRI findings (6.2%). Most MRI examinations had more than one abnormal finding (84%). Age at which MRI examinations were performed was not significantly different between boys and girls. All six categories of abnormal MRI findings were not significantly different between boys and girls. Conclusion  Children with JpsA typically present with more than one abnormal finding on their MRI studies. While synovial abnormality is the most common MR finding in children with JpsA, multi-focal bone marrow edema and enhancement at both articular and non-articular sites are also notable findings in children with JpsA. The rate of articular abnormality is much lower in children with JpsA in comparison to adults with psoriatic arthritis. Our findings suggest that MRI can play a useful role in the diagnosis and ongoing assessment of this uncommon, though important, pediatric rheumatologic disorder.     

MR imaging findings in transient osteoporosis of the hip

Purpose: The authors sought to describe the magnetic resonance (MR) imaging findings including perfusion imaging, in association with the course of acute bone marrow oedema syndrome (aBMEs), in a group of patients with acute hip pain and a final diagnosis of transient osteoporosis of the hip (TOH). Materials and methods: From 217 patients referred with a probable diagnosis of avascular necrosis (AVN) of the femoral head, we identified 42 patients who had clinical and radiographic findings not relevant to AVN. MR imaging examinations were performed on a 1.0T scanner. Perfusion imaging was performed in 20 patients. The bone marrow oedema (BME) was classified in four stages. In addition, the presence or absence of oedema in the subchondral area and the presence of other subchondral lesions were recorded. Acetabular bone marrow was also assessed for the presence of oedema. The quantitative measurements included: maximum size of the effusion, percentage of enhancement (PE) and time of peak enhancement of abnormal marrow compared to the first pass, on the perfusion images. Results: Osteopenia was present on plain radiographs in 87% of cases. The most common pattern of BME was extending to the femoral head and neck. Acetabulum was involved in 16.6%. In 22.6% the BME spared the subchondral region of the femoral head. There were two cases (4.7%) with subchondral changes. A joint effusion was noted in 33 of the 42 patients. On perfusion imaging, a delayed peak enhancement was noted in 20 patients between 40 and 65 s after the first pass of contrast. No patient had any evidence of femoral head collapse or change in sphericity on follow-up MRI. None of the patients developed avascular necrosis in a time frame of 18 months from the onset of the acute hip pain. Conclusion: The aBMEs MR imaging pattern varies and is most commonly appearing on X-rays as osteopenia. Absence of subcondral lesions, delayed peak enhancement of the abnormal marrow on perfusion images, and sparing of subchondral zone from marrow oedema are MR imaging findings highly correlated to TOH.     

Magnetic resonance imaging of the normal and ischemic femoral head

The femoral heads of 38 normal and 20 abnormal patients were evaluated using magnetic resonance imaging (MRI). The normal femoral head is surrounded by a thin, sharply defined, low-intensity cortex. The medullary cavity has a strong signal intensity in all imaging sequences due to the large content of marrow fat and hematopoietic cells. Crossing the high-intensity marrow is a thin, curvilinear, transverse, low-intensity line representing the physis and a broad, vertically oriented, low-intensity band resulting from the prominent central weight-bearing trabeculae. Anatomic structures can be identified on all scanning sequences if the examinations are technically satisfactory, although images with the best clarity and detail are obtained by using short echo times. MRI of patients with ischemic necrosis revealed areas of low intensity in the femoral heads. The abnormal areas may take the form of homogeneous regions of decreased signal intensity, inhomogeneous areas of low intensity, bands of low intensity, or rings of low intensity with higher signal intensity centrally. No correlation was found among the specific MRI patterns, the stage of the disease, the radiographic appearance, or the radionuclide bone scan findings. MRI was abnormal in all cases where the radiographs or the scintigraphs (or both) were abnormal. MRI also was abnormal in several cases where either radiographs or scintigraphs produced false-negative results.     

How does iliac crest bone marrow biopsy compare with imaging in the detection of bone metastases in small cell lung cancer?

Iliac crest bone marrow biopsy (BMB) has often been used as the gold standard for the detection of bone marrow metastases in small cell lung cancer (SCLC). However, it is likely to lead to numerous false-negative results. For this reason, we compared the results of bone scintigraphy (BS), magnetic resonance imaging (MRI), and BMB in 48 sequential patients affected with pathologically confirmed SCLC (47 were evaluable; mean age, 58.4 years). The three procedures were carried out within 1 week, no treatment being performed during this period. Whole-body scans and spot views were obtained in the anterior and posterior projections. For MRI, only the thoracolumbar spine, the sternum and the pelvis were scanned, using spin-echo T1-weighted sequences, resulting in an acquisition time of less than 45 min. Only five BMBs were rated as positive. In these cases, both BS and MRI were also positive. The other 42 biopsies were negative. Among them, in ten cases both BS and MRI were positive. In 21 cases, both BS and MRI were negative. In five cases MRI was positive while BS was negative. Finally, in six cases MRI was negative whilst BS was positive. In most cases in which either BS or MRI was positive, follow-up scans confirmed the initial findings. This study suggests that BMB is more invasive and less sensitive than BS or MRI in detecting bone metastases. MRI seems to be more sensitive than BS in detecting small spinal or pelvic metastases. Whole-body bone scintigraphy is more sensitive in detecting skull, costal or peripheral metastases. BS and MRI should be used in combination and may replace BMB in the detection of bone metastases in SCLC. Correspondence to: I. Perrin-Resche     

MR imaging findings in the follow-up of patients with different stages of knee osteoarthritis and the correlation with clinical symptoms

Objective: To assess the rate of cartilage loss, the change in bone marrow edema pattern and internal joint derangement at 1.5-T MRI in patients with knee osteoarthritis and to correlate these findings with the clinical Western Ontario and McMaster University Osteoarthitis (WOMAC) score. Methods: Forty subjects (mean age 57.7±15 years; 16 females and 24 males) were recruited: 6 healthy volunteers (OA0), 17 patients with mild osteoarthritis (OA1) and 17 with severe osteoarthritis (OA2) based on the Kellgren-Lawrence scale. MR scans, radiographs and WOMAC scores were obtained at baseline, first follow-up (1.4±0.67 years; n=40) and second follow-up (2.4±0.4 years; n=26). Cartilage morphology, bone marrow edema (BME), meniscal and ligamentous pathology were assessed on MR images and quantified by two radiologists in consensus. Results:Full-thickness cartilage lesions were observed in 12/17 OA2 at baseline, in 13/17 at the first follow-up and in 7/10 at the second follow-up. Cartilage loss was found in eight patients at the first follow-up and five at the second follow-up. BME was observed in 23/40 patients at baseline, in 22/40 at the first follow-up and in 12/26 at the second follow-up. Changes in BME were visualized in 19/22 and 4/13 patients at the first and second follow-up, respectively. Changes in WOMAC scores over time did not correlate significantly with the amount of cartilage loss and the change in BME (P>0.05). Conclusion:MRI is well suited to monitor the progression of OA in the longitudinal follow-up since it shows cartilage defects, BME and internal joint derangement, pathologies that are not visualized by radiographs. The lack of significant correlation between MRI findings and clinical findings is not unexpected, has been previously described and may in part be due to the fact that patients get more accustomed to their pain as the knee progressively degenerates.     

Magnetic resonance imaging of the lower vertebral column in patients with multiple myeloma

Eighteen patients with multiple myeloma (clinical stages 1-3) and a control group of 21 persons underwent magnetic resonance imaging (MRI) studies of the lower thoracic and lumbar spine. This was done to determine the potential benefit of MRI in addition to conventional radiographs, tomograms, computed tomography and nuclear scans. In addition to focal fatty replacement of normal hematopoietic marrow, which presented as focal hyperintense lesions on T1-weighted images (T1-WI) and on T2-weighted images (T2-WI), two types of myelomatous lesions were found: (1) focal areas with reduced signal intensity when compared with normal bone marrow on T1-WI and enhanced signal intensity on T2-WI, mainly found in untreated myelomas; and (2) focal areas of decreased signal intensity on T1-WI and on T2-WI, which were predominantly detected after previous radiation therapy. MRI surpassed conventional radiography in detecting abnormal focal marrow infiltration in 41 of 247 vertebrae. Radiographs identified only 11 of the 41 as pathologic, based on shape and structure of the vertebral bodies; however, 15 other collapsed vertebrae showed no signal abnormalities of the marrow on MR images. Discrimination of normals and abnormals by statistical analysis of intensity measurements of the bone marrow was not possible.     

Magnetic resonance imaging in the evaluation of suspected osteonecrosis of the knee

Magnetic resonance imaging (MRI) was performed on 19 patients with suspected or proven osteonecrosis of the knee. The results were compared to radionuclide and plain radiographic studies when possible. The patients were grouped into one of three categories: patients with disease predisposing them to osteonecrosis (e.g., systemic lupus erythematosus (SLE), steroid use, and renal transplants), older patients without risk factors with acute onset of symptoms, and patients with knee pain months or years following trauma.In six patients with symptoms and predisposing diseases, MRI was abnormal in four cases, all of whom had bilateral abnormalities. In the ten older patients with classical symptoms, MRI was abnormal in seven, and bilateral abnormalities were present in three patients. The three patients with a history of antecedent trauma had normal MRI studies. Two patients with history and scintigraphic cvidence of osteonecrosis had negative MRI scans. MRI may be of value in patients with suspected or proven osteonecrosis of the knee by demonstrating bilateral disease in patients with unilateral symptoms, showing the extent of involvement, and establishing the presence or absence of bone marrow changes in patients with positive bone scans and negative plain films.     

Magnetic resonance in the staging of multiple myeloma]

The authors retrospectively reviewed the MR examinations of 46 patients with clinical and laboratory findings of monoclonal gammopathies (MG). All cases had been submitted to radiographic examination which had shown skeletal involvement in 22 cases and osteoporosis in 11, with rupture of the vertebral body in 3 patients. Scintigraphy had been performed on all patients and CT on 12; 36 patients were subsequently submitted to follow-up (at 6, 12 and 24 months). MR examinations were performed with dedicated coils and standard sequences for the subjects with skeletal localizations on X-ray images. The extant cases, with no radiographic evidence of skeletal involvement, were submitted to MRI of the spine, skull and pelvis. In agreement with clinical and laboratory findings and with follow-up results (in 36 patients), MRI diagnosed MG with no skeletal involvement in 13 cases, osteoporosis in 8 (with rupture of the vertebral body in 2), asymptomatic non-progressive myeloma in 4, solitary myeloma in 3, and multiple myeloma in 18 cases. The good identification of bone marrow and its multiplanarity make MRI the method of choice in the study of patients with suspected or known gammopathies. If compared with other modalities, MRI is more sensitive and accurate in depicting the tumor, its size and relationship to periskeletal tissues, and its possible multifocality. Moreover, the technique has proven to be a valid tool during the follow-up, showing tumor response to therapy.     

足踝部X线表现阴性痛风性关节炎的CT与MRI表现对比研究

目的:对足踝部X线平片表现阴性痛风患者的CT和MRI表现进行对比研究,评估其隐匿性骨质破坏及其他影像学表现。方法:收集于我院就诊的36例X线平片阴性痛风患者,于2周内均行CT与MRI平扫,分析骨质破坏、关节内和/(或)周围痛风石、软组织肿胀、关节腔积液、滑膜增厚和骨髓水肿等征象。结果:36例CT平扫可见骨质破坏23例,MRI可见13例,二者差异有统计学意义(P=0.002)。CT平扫可见关节内和/(或)周围痛风石23例,MRI可见27例,二者差异无统计学意义(P=0.289);其中21例CT、MRI均见痛风石表现,6例仅MRI可见,2例仅CT可见。CT与MRI平扫分别有11例和15例可见关节腔积液表现,二者差异无统计学意义(P=0.125)。2种检查均见软组织肿胀24例,差异无统计学意义(P=1.000)。另外,36例的MRI平扫中,4例可见滑膜增厚,30例见骨髓水肿表现。结论:CT与MRI平扫可显示X线平片无法显示的隐匿性骨质破坏及微小痛风石,CT平扫对于早期骨质破坏的显示优于MRI,但MRI可提供更多影像信息。对于足踝部X线表现阴性痛风性关节炎,CT与MRI相结合为最佳检查手段。     

Detecting bone marrow metastases at the time of examining the liver with radiocolloid

In a prospective study of 200 different consecutive patients with cancer, the bone marrow of the lumbar spine and pelvis has been examined at the time of obtaining a radiocolloid examination of liver and spleen. The images were examined "blind" by three observers who all agreed about the findings in 177 (89%) of the patients. Agreement by any two was considered to be definitive. The radiocolloid marrow examinations in this selected population had an accuracy of 0.97, sensitivity of 0.80, and specificity of 0.98 in diagnosing metastatic disease when validated by all other available evidence, or follow-up. Of the patients thus examined, 16 (8%) had abnormal marrow scan findings reflecting metastatic disease, eight (4%) at the time radiographs were normal, and two at the time bone scintigraphy was normal. Excluding patients with bowel cancer, in whom the detection rate was zero, 16 (12.4%) marrow examinations were abnormal. As a result we now obtain "saturated" images of the marrow incidental to radiocolloid examinations of the liver and spleen in patients with cancer other than that of the bowel.     

儿童急性白血病四肢骨关节的影像研究

目的 探讨急性白血病儿童患者四肢骨关节的X线和MRI特点.方法 搜集以骨关节疼痛为主诉,经临床及骨髓穿刺确诊为急性白血病的13例患儿,对其疼痛部位均行X线平片检查,8例同时行MR检查,其中4例经过化疗达完全缓解后1周内行原疼痛部位的X线和MRI复查.对2种不同影像表现进行分析.结果 13例中,6例X线表现正常,7例共14处可见骨质异常:十骺端透亮带5处,骨膜反应3处,混杂密度骨质破坏1处,浸润性骨质改变3处,骨质疏松2处.MR检查8例共11处,6例共9处MRI表现为骨髓浸润、坏死,X线表现正常;2例共2处MRI表现为骨髓浸润,X线可见骨膜反应及干骺端透亮带.4例化疔达完全缓解后1周内复查,MRI显示骨髓浸润、坏死病灶范围缩小并T1WI骨髓信号不均匀增高,坏死灶呈较均匀长T1、长T2信号,边界清晰,双边征消失,相同病例治疗前后X线复查未见明显改变.结论 以骨关节痛为主诉的急性白血病患儿,MRI较X线能更早期、全面地检测到骨关节的病变,MRI可作为临床疗效监测的指标之一.

Abstract：

Objective To evaluate X-ray and MRI features of limbs in childhood acute leukemia.Methods Thirteen children with acute leukemia in our pediatric hematology ward were recruited.Allpatients were pathologically diagnosed by bone marrow aspiration and complained of bone or joint pain in the first visit.ConventionaI X-ray and MRI examinations of algesic sites were performed before clinical treatment and after complete remission.MR images were obtained with SE-T1WI,SE-T2WI and T2WI-fat suppressed sequences and symmetria bilateralis was requested while scanning.X-ray and MRI manifestations were evaluated and compared.Resuits All 13 patients had received X-ray examinations.Among them,6 had normal X-ray findings,whereas the other 7(14 sites)showed various abnormalities including radiolucent metaphyseal bands(5 sites),periosteal reaction(3 sites),osteapenia(2 sites),mixed lesions(lysissclerosis,1 site),and permeative pattern(3 sites).The number of patients for MRI examinations was 8(11 sites).Among them,6(9 sites)showed bone marrow infiluration and bone marrow necrosis accompanied by normal X-ray findings,another 2(2 sites)showed bone marrow infiltration associated with radiographic abnormalities of periosteal reaction and radiolucent metaphyseal bands.Four cases were followed up within 1 week when reached complete remission by chemotherapy.MR images features included reduced sizes of bone marrow infiltration lesions associated with increased signal intensity on T1WI,and disappearance of double-line sign on bone marrow necrosis accompanied by signal homogenization.However,the radiograph before and after treatment in the same cases did not differ significantly.Conclusions MRI was earlier and more comprehensive in showing limbs bone marrow abnormality than radiogram in acute leukemia children with chief complaint of osteoarticular pains.MRI might be one of indicators in following up therapeutic effect for AL children with osteoarticular disorder.     

Paget disease: MR imaging findings

Magnetic resonance (MR) images of 13 patients with Paget disease were reviewed, and findings were correlated with those from computed tomographic (CT) scans, radiographs, and, in two patients, surgical biopsy. MR imaging findings correlated with CT and radiographic findings of cortical thickening, increased size of bone, and coarse thickened trabeculae. Focal or diffuse decreased signal intensity, representing dense bone, was seen on images obtained with short and long repetition times (TRs) and echo times (TEs); high-signal foci, representing fat collections, were seen on short TR/TE images; and high-signal foci, representing fibrovascular marrow in active Paget disease, were seen on long TR/TE images. Complications of Paget disease-including basilar invagination, spinal stenosis, and sarcoma--were well identified on MR images. Although MR imaging is not generally used in diagnosis of Paget disease, the disease will be encountered more frequently as more MR imaging examinations are performed. An awareness of the range of findings in Paget disease is useful in evaluating MR images of the musculoskeletal and other systems.