Marrow Magnetic Resonance Research Articles

Bone marrow magnetic resonance imaging (MRI): morphological and functional features from reconversion to infiltration.

Bone marrow is a dynamic organ with variable composition in relation to age or pathophysiological changes. Magnetic resonance imaging (MRI) is the technique of choice to assess the different components of the bone marrow based on the different information provided by the different characteristics of the MRI sequences. This article provides an overview of the MRI appearances of normal and abnormal bone marrow. We review the MRI features of normal developmental red marrow- to yellow-conversion, reconversion and physiologic conditions. We review the key imaging techniques used in assessing bone marrow pathology in MRI, including T1-weighted, T2-weighted, Dixon chemical shift imaging and diffusion-weighted imaging, as well as dynamic contrast-enhanced (DCE) MRI. It is discussed the bone marrow characteristics in the different morphological and functional MRI sequences from the normal or abnormal conditions such as; infiltration (metastases), proliferation [multiple myeloma (MM)], vascular edema/necrosis and postreatment changes. We show the different MRI features to differentiate physiological processes from pathological processes in order to provide effective diagnoses, as well as to evaluate the optimal therapeutic monitoring assessment. Insights from recent advancements in imaging technology and emerging MRI techniques are also discussed, providing a comprehensive overview of bone marrow MRI and its clinical implications. This review provides a useful tool for radiologist to decide normal or abnormal findings from the analysis of bone marrow MRI; in order to manage and take decisions that will depend on the imaging findings. The optimal analysis of bone marrow MRI requires knowledge of the physiology of the bone marrow to interpret properly the pathology and avoid diagnostic errors.

Quantitative bone marrow magnetic resonance imaging in children with lymphoblastic leukaemia

The aim of the study was to evaluate fat fraction (FF) changes in patients diagnosed with acute lymphoblastic leukaemia (ALL) in comparison with children without haematological disorders. All the patients or their legal representatives gave their informed consent to magnetic resonance imaging (MRI). The study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology and was conducted in line with the Ethical Principles of the World Health Organization (the Declaration of Helsinki) for Medical Research Involving Human Subjects. The study included 33 healthy volunteers aged 13.4 ± 2.8 years (the control group) and 34 patients with acute phase ALL whose mean age was 12.2 ± 3.6 years (the group of interest). Imaging of the pelvic bones and lumbar vertebrae was performed on a Philips Achieva 3T scanner using the mDixon-quant sequence, with a subsequent construction of FF maps. The Mann–Whitney U-test was used to compare the FF data of the cases with each other and with the controls. Four regions of interest were selected, 100 mm2 each: in the bodies of the right and the left iliac bones as well as in the bodies of the L4 and L5 vertebras. For each group of subjects and each region of interest, mean FF was calculated. In the group of the patients with acute phase ALL, FF was the lowest: 3.53 ± 2.75% and 3,72 ± 3.09% in the bodies of the left and right iliac bones respectively, and 2.62 ± 1.86% and 2.47 ± 2.17% in the L4 and L5 vertebras respectively. In the control group, FF in the respective regions of interest was 51.3 ± 9.5%; 49.9 ± 11.0%; 31.3 ± 8.73% and 32.4 ± 10.3%. It is obvious that bone marrow FF in the patients with ALL differs significantly from the control group. Quantitative MRI can become a new method for the assessment of changes in the bone marrow of children with leukaemias.

Femoral marrow MRI is a non-invasive, non-irradiated and useful tool for detecting bone marrow involvement in non-Hodgkin lymphoma.

Femoral marrow magnetic resonance imaging (MRI) is a non-invasive, non-irradiated and useful modality for evaluating bone marrow (BM) conditions. Human adult femoral BM is almost uniformly fatty marrow and has the largest volume of a single bone. MRI has an extremely high resolution for fat and water, which allows high-contrast imaging of cellular infiltration into fat tissue. In hematological diseases, femoral BM MRI can clearly detect cell infiltration, which is symmetrically imaged from the proximal to the distal direction of abnormal signal areas. Thus, we investigated the significance of femoral MRI for non-Hodgkin lymphoma (NHL). We analyzed the data of 69 NHL patients who received femoral MRI at diagnosis in this single-center retrospective cohort study. The median patient age was 73 years. MRI patterns were mainly classified as uniform patterns or nonuniform patterns. We also classified the range of cellular marrow as high-grade or low-grade based on whether it had spread to over half of the femur. Both overall survival (OS) and progression-free survival (PFS) were significantly influenced by abnormal femoral marrow MRI. In particular, the patients with cellular femoral marrow lesions had a worse OS and PFS based on log-rank tests. Multivariable analyses with the Cox proportional hazards model revealed that OS and PFS were significantly influenced by cellular marrow diagnosed by femoral MRI. We concluded that femoral marrow MRI is a useful tool for detecting BM involvement and an independent prognostic factor in NHL patients.

Quantitative bone marrow magnetic resonance imaging through apparent diffusion coefficient and fat fraction in multiple myeloma patients.

Quantitative bone marrow (BM) MR sequences, as DWI and CSI, were used to evaluate BM water-fat composition. The aim of the study was to assess the potential usefulness of fat fraction (FF) and ADC, calculated by CSI or DWI, in diagnosing and classifying myeloma (MM) patients according to their different BM infiltration patterns. The study group included 43 MM patients (19F; 24M; mean age 64years), 15 asymptomatic, 15 symptomatic with diffuse BM infiltration and 13 symptomatic with focal lesions (FLs). The control group was made up of 15 healthy subjects (7F; 8M; mean age 64years). MRI examinations consisted of sagittal T1w TSE on the spinal column, axial DWI (b 50-400-800mm2/s) and coronal T2 Dixon, on the whole body. Mean ADC and FF were calculated placing 1 ROI on 6 vertebras and 2 ROIs on either the pelvis or FL. ANOVA with Bonferroni's correction showed a significant difference in ADC values among the different groups of MM patients (P < 0.05), while FF was only significantly different between patients with diffuse infiltration and patients with FL (P = 0.002). ADC allowed distinguishing MM patients from normal BM patients with diffuse BM infiltration (cutoff value: 0.491 × 10-3mm2/s; sensitivity 73%, specificity 80%). FF helped better discriminate healthy controls from normal BM patients (cutoff = 0.33, sensitivity 73%, specificity 92%) and patients with diffuse BM infiltration from those with FL (cutoff = 0.16, sensitivity 82%, specificity 92%). ADC and FF are potentially useful parameter for the quantitative evaluation of BM infiltration in MM patients.

Bone marrow magnetic resonance imaging: physiologic and pathologic findings that radiologist should know.

Magnetic resonance imaging (MRI) plays a leading role in the non-invasive evaluation of bone marrow (BM). Normal BM pattern depends on the ratio and distribution of yellow and red marrow, which are subject to changes with age, pathologies, and treatments. Neonates show almost entirely red marrow. Over time, yellow marrow conversion takes place with a characteristic sequence leading to a red marrow persistence in proximal metaphyses of long bones. In adults, normal BM is composed of both red (40% water, 40% fat) and yellow marrow (15% water, 80% fat). Due to the higher content of fat, yellow marrow normally appears hyperintense on T1-weighted (T1w) fast spin echo (FSE) sequences and hypo-/iso-intense in short tau inversion recovery (STIR) T2-weighted (T2w); red marrow appears slightly hyperintense in T1w FSE and hyper-/iso-intense in STIR T2w. Pathologic BM has reduced fat and increased water percentages, resulting hypointense in T1w FSE and hyperintense in STIR T2w. In oncologic patients, BM MRI signal largely depends on the treatment (irradiation and/or chemotherapy) and its timing. BM fat and water amount and location in normal red/yellow and pathologic marrow are responsible for different signals in MRI sequences whose knowledge by radiologists may help to differentiate between normal and pathologic findings. Our aim was to discuss and illustrate the MRI of BM physiologic conversion and pathologic reconversion occurring in malignancies and after treatments in cancer patients.

Change in liver, spleen and bone marrow magnetic resonance imaging signal intensity over time in children with solid abdominal tumors.

Reticuloendothelial system MRI signal hypointensity is common in pediatric oncology patients with solid abdominal tumors. To assess changes in liver, spleen and bone marrow T2-weighted MRI signal intensity over time and their relationship to blood transfusion history in children with solid abdominal tumors. In this retrospective study we measured liver, spleen and bone marrow signal intensity on axial T2-weighted MR images obtained December 2009 through February 2016 in children with hepatoblastoma, neuroblastoma, ganglioneuroblastoma and Wilms tumor. All signal intensity measurements were normalized to paraspinal muscle signal intensity. We used linear mixed models (including a day*day quadratic term) to determine whether organ signal intensity changed over time and whether change was associated with blood transfusion volume or tumor type. We included 133 children (mean age at diagnosis =2.9years); 56 had neuroblastoma, 42 hepatoblastoma, 28 Wilms tumor and 7 ganglioneuroblastoma. Seventy-nine (59.4%) children received transfusions (median: 8 transfusions, range: 1-30; mean volume: 1,148.5mL). Hepatic, splenic and bone marrow signal intensity ratios changed quadratically over time for the study population, initially decreasing and then increasing (P<0.0001). Children receiving less than the mean blood transfusion volume showed no significant change in tissue signal intensity, while those receiving more than the mean volume showed significant changes in signal intensity over time (P<0.0001). Compared to children with Wilms tumor, those with neuroblastoma exhibited significantly lower hepatic (P=0.03) signal intensity ratios. Liver, spleen and bone marrow T2-weighted MRI signal intensity ratios change over time in some pediatric patients with solid abdominal tumors, likely from tissue iron deposition related to blood transfusions and perhaps because of tumor type.

Bone marrow magnetic resonance imaging of the clivus in pediatric leukemia patients and normal controls.

An MRI-based pre-test to determine the probability of pediatric leukemia prior to bone marrow aspiration would be useful to prevent unnecessary exposure to this invasive test. We aimed to evaluate the clivus-to-pons signal intensity ratio (CPR) and visual scoring (VS) on T1-weighted images (T1WI) and diffusion-weighted images (DWI) to distinguish pediatric leukemia patients from normal controls. We retrospectively reviewed 1.5-T brain MR images of 13 consecutive leukemia patients (3 girls, 10 boys; mean age, 8.23 years; range, 1-17 years) and 40 age- and gender-matched normal controls. We evaluated differences between leukemia patients and normal controls using Wilcoxon rank-sum and Mann-Whitney U tests with respect to the following parameters: (1) CPR on T1WI (CPRT1WI); (2) CPR on DWI (CPRDWI); (3) VS on T1WI (VST1WI); and (4) VS on DWI (VSDWI). The CPRT1WI values for leukemia patients and normal controls were 0.77 ± 0.12 and 1.39 ± 0.47, respectively (P < 0.001). The corresponding CPRDWI values were 1.03 ± 0.38 and 0.50 ± 0.17, respectively (P < 0.001). VST1WI and VSDWI were significantly different between the groups (P < 0.001 for both). MRI-based quantitative and qualitative analyses of clival bone marrow on T1WI and DWI can distinguish pediatric leukemia patients from normal subjects.

Magnetic resonance imaging of the spinal marrow: Basic understanding of the normal marrow pattern and its variant

For now, magnetic resonance (MR) is the best noninvasive imaging modality to evaluate vertebral bone marrow thanks to its inherent soft-tissue contrast and non-ionizing nature. A daily challenging scenario for every radiologist interpreting MR of the vertebral column is discerning the diseased from normal marrow. This requires the radiologist to be acquainted with the used MR techniques to judge the spinal marrow as well as its normal MR variants. Conventional sequences used basically to image marrow include T1W, fat-suppressed T2W and short tau inversion recovery (STIR) imaging provides gross morphological data. Interestingly, using non-routine MR sequences; such as opposed phase, diffusion weighted, MR spectroscopy and contrasted-enhanced imaging; may elucidate the nature of bone marrow heterogeneities; by inferring cellular and chemical composition; and adding new functional prospects. Recalling the normal composition of bone marrow elements and the physiologic processes of spinal marrow conversion and reconversion eases basic understanding of spinal marrow imaging. Additionally, orientation with some common variants seen during spinal marrow MR imaging as hemangiomas and bone islands is a must. Moreover, awareness of the age-associated bone marrow changes as well as changes accompanying different variations of the subject's health state is essential for radiologists to avoid overrating normal MR marrow patterns as pathologic states and metigate unnecessary further work-up.

Diffuse MRI Marrow Pattern Correlates with Increased Angiogenesis, Advanced Disease Features and Poor Prognosis in Newly-Diagnosed Patients with Multiple Myeloma Treated with Novel Agents.

Abstract 829The aim of this study was to evaluate the prognostic value of bone marrow magnetic resonance imaging (MRI) in newly-diagnosed myeloma (MM) patients who received novel agent-based therapy and to explore possible correlations of MRI pattern with clinical and laboratory data. Eighty-two consecutive MM patients (43M/39F, median age: 65 years) at diagnosis were studied. MRI of the spine was performed within 1-2 weeks following diagnosis. T1-weighted, STIR and contrast-enhanced T1-weighted sagittal MR images of the thoracic and lumbar spine were obtained with a 1.5 T unit (Phillips, Eindhoven, the Netherlands). Marrow involvement was characterized as normal, focal, diffuse or variegated. Microvessel density (MVD) was evaluated in marrow trephine biopsies at the time of diagnosis. The following serum indices of bone metabolism and angiogenesis were measured on the day of MRI: i) osteoclast stimulators [sRANKL, osteoprotegerin (OPG), osteopontin (OPN) and macrophage inflammatory protein-1alpha (MIP-1alpha)], ii) dickkopf-1 (Dkk-1), iii) bone resorption markers [C- and N-terminal cross-linking telopeptide of collagen type-I (CTX and NTX, respectively) and TRACP-5b], iv) bone formation markers [bone alkaline phosphatase (bALP) and osteocalcin (OC)], and v) angiogenic cytokines [VEGF, VEGF-A, angiogenin (ANG), angiopoietin-1 (ANGP-1), angiopoietin-2 (ANGP-2) and bFGF]. MRI evaluation of the spine revealed that 34 (41.5%) patients had focal, 26 (31.7%) diffuse, 18 (22%) normal, and 4 (4.9%) had a variegated pattern of marrow involvement. Low-grade angiogenesis, as assessed by MVD, was present in 32 (39%) patients, while 33 (40%) had intermediate-grade and 17 (20%) patients had high-grade angiogenesis. Twenty-one of 26 (80%) patients with a diffuse MR pattern had intermediate or high-grade angiogenesis in contrast to 14/34 (41%) patients with focal involvement (p=0.01) and 12/18 (66%) with normal MR pattern (p=0.037). Patients had increased values of VEGF (p<0.001), VEGF-A (p<0.001), ANGP-2 (p<0.001) and bFGF (p=0.001), and reduced values of ANGP1/ANGP2 ratio (p<0.01) compared to healthy controls (n=36). Patients with a diffuse pattern were the only patients who had increased ANG compared to controls (p=0.004). Patients with diffuse pattern had higher levels of serum VEGF and VEGF-A compared to patients with normal (p=0.028 and p=0.006, respectively) and focal pattern (p=0.009 and p<0.01, respectively) and borderline elevated ANG compared to normal pattern (p=0.06). Myeloma patients had increased values of sRANKL (p<0.001), sRANKL/OPG ratio (p=0.004), NTX (p<0.001), CTX (p<0.001), TRACP-5b (p<0.001), Dkk-1 (p=0.01), and OPN (p<0.001) and borderline reduced values of bALP (p=0.09) compared to controls. Patients with normal MRI pattern showed no difference in terms of Dkk-1 and bone formation markers compared to controls. Patients with diffuse pattern of marrow involvement had reduced values of bone formation markers (p=0.01), while patients with focal pattern had only a borderline reduction of OC (p=0.09). Both diffuse and focal MRI patterns had increased Dkk-1 levels. All abnormal MRI patterns had increased levels of NTX, CTX and TRACP-5b and increased levels of osteoclast stimulators sRANKL/OPG, MIP-1alpha and OPN. Diffuse and variegated patterns of infiltration correlated with greater bone marrow plasma cell infiltration (p=0.043) and advanced ISS stage (p=0.018). All patients received a combination regimen that contained at least one novel anti-myeloma agent (IMiD and/or bortezomib) at some point during the course of their disease. The median follow-up of the patients was 25 months. Patients with diffuse or variegated pattern had a median survival of 29 months, patients with focal pattern had a median survival of 62 months, while the median survival of patients with normal MRI pattern has not been reached at the time of the analysis (p=0.009). Multivariate analysis showed that only MRI pattern and ISS stage were independent prognostic factors for survival. In conclusion, our analysis provides strong evidence that diffuse MRI pattern of marrow involvement correlates with increased angiogenesis, adverse disease features and inferior survival in MM patients who were treated with novel agents. Such patients may be considered for upfront treatment with combinations of novel agents. Our results highlight the important prognostic value of MRI in MM and support its routine use in MM patients. Disclosures:No relevant conflicts of interest to declare.

New Perspectives on Bone Marrow Contrast Agents and Molecular Imaging

Magnetic resonance (MR) imaging of bone marrow provides a noninvasive diagnosis of the vascularity, cell quantity, and composition of the normal and pathological bone marrow. This article reviews new and evolving techniques for bone marrow MR imaging with a special focus on translational and clinical applications. Evaluations of bone marrow perfusion with standard small molecular contrast agents and, more recently, with macromolecular contrast agents are currently being applied for therapy monitoring. Cell-specific contrast agents are expected to improve the sensitivity and specificity of bone marrow MR imaging. Novel cellular and molecular imaging techniques for the depiction of cell metabolism and specific biochemical pathways are discussed. Cell tracking techniques may allow specific diagnoses of inflammatory processes as well as monitoring of novel therapies based on stem cells. Future developments of fusion imaging techniques and bifunctional contrast agents are directed to combine comprehensive information about bone marrow structure and function with targeted and image-guided therapies.

Improved Sensitivity of Bone Marrow Magnetic Resonance Imaging (BM-MRI) in Quantifying the Extent of Bone Marrow Involvement in Patients with Multiple Myeloma (MM).

Background: Traditionally, bone marrow aspirate/biopsy (BM-Bx) has been used for diagnosis and quantification of the extent of disease as well as response to therapy in MM patients. This information is used to make decision for treatment initiation. Since MM is not a contiguous disease, marrow involvement can be patchy and BM-Bx may be misleading in assessing the true extent of the disease. BM-MRI is a non-invasive technique that can evaluate a large amount of marrow for tumor infiltration. We prospectively investigated the sensitivity of BM-MRI and compared its results with those obtained by BM-Bx as well as with the clinical stage of disease.Methods: All patients with the diagnosis of MM who had BM-MRI at our center were evaluable. Patients must have received a BM-Bx within 4 weeks of the BM-MRI. In these patients sagittal T1 and fast spin echo inversion recovery sequences of the cervical, thoracic and lumbosacral spine and coronal T1 and fast spin echo inversion recovery sequences of the sacrum and pelvic bones were reviewed on the MRI. Durie-Salmon (DS) staging criteria were used for correlation. To study the statistical relationship between pairs of ordinal variables the test corresponding to the Spearman correlation was used. To study the statistical relationship between nominal and ordinal variables, the Wilcoxon or Kruskal-Wallis test was used. A 0.05 nominal significance level was used in all testing. Following staging system was defined for evaluation of the involvement of the marrow by BM-MRI: A (0%), B (< 10%), C (10%–25%), D (26%–50%), E (> 50%). Results of this were then compared with the extent of involvement reported on histological evaluation of the BM-Bx.Results: A total of 50 patients (23 females and 27 males) were identified. Median age was 61.5 years (range 35–82 years) with 23 (46%) having stage IIIA disease. As per the staging system defined above, 6%, 10%, 10%, 22% and 52% of the patients had categories A, B, C, D and E involvement as per BM-MRI, respectively. Similarly, involvement observed on the BM-Bx was 8%, 24%, 22%, 16% and 30%, respectively. Categories of marrow involvement on BM-Bx and BM-MRI were concordant in 23 (46%) and discordant in 27 (54%) patients. Of the patients that showed discordance, 89% had a more extensive BM involvement detected by the BM-MRI and 11% had a higher reading on BM-Bx. The estimated Spearman correlation coefficient between MRI involvement and MM stage was 0.4849 (95% CI; 0.2494, 0.7205), showing a significant association between BM-MRI involvement and MM stage (p =0.0002). The estimated Spearman correlation coefficient between BM-Bx involvement and MM stage was 0.1775 (95% CI; −0.1406, 0.4956), showing no significant association between BM-Bx involvement and MM stage (p = 0.2764).Conclusions: We demonstrate for the first time that BM-MRI is a more sensitive technique to assess the true disease burden in MM and is significantly better than BM-Bx. We also observe that the extent of marrow infiltration noted on the BM-MRI correlates significantly with other prognostic characteristics like DS stage. Based on this observation we recommend that BM-MRI should be considered as part of the pre-treatment evaluation of patients with multiple myeloma.

Volume Localized In Vivo Proton MR Spectroscopy of Multiple Myeloma: Variation of Water-Fat Ratio in Patients Receiving Chemotherapy Correlates with Clinical Response.

Introduction. Bone marrow magnetic resonance (MR) imaging provides important information i<SPACER size="24">n the evaluation of patients with multiple myeloma (MM) but MR assessment of response to therapy is highly subjective. Proton nuclear magnetic resonance spectroscopy (1H MRS) may be able to measure the ratio of lipid to water resonance signal intensities (LWR) and thus reflect the relative percentages of cellular and fatty bone marrow within a defined three-dimensional volume (voxel). These measurements could be used to quantify the degree of cytoreduction in MM patients.Patients and Methods. Twenty-one consecutive patients (10 male; median age 65 years, range 44–82) with newly diagnosed multiple myeloma underwent a MR exploration of the fifth lumbar vertebral body before the initiation of treatment. Patients completing therapy were reevaluated. Dorso-lumbar imaging studies were carried out in a 1.5T system with a saggital spin-echo T1-weighted sequence (TR 437 ms / TE 15 ms). A 2-cm-thick transverse center section of the L5 lumbar vertebral body was sampled to place the voxel. Spectroscopic data were acquired with a stimulated echo acquisition mode (STEAM) sequence without water suppression with repetition time 5 s and echo time 40 ms. To calculate the area of the water signal, the peak was fit to a single Lorenzian curve centered at 4.75 ppm. The area of the lipid resonances was fit to 3 Lorenzian curves centered at 0.89 (-CH3), 1.34 and 2.2 (-CH2) ppm. The areas obtained were used to calculate the LWR for each voxel. The LWR was defined as the sum of the area of the 3 lipid fitted resonances divided by the area of the fitted water resonance.Results. The spectra showed a water peak and a compounded lipid peak separated by approximately 3.1 ppm. LWRs ranged from 0 to 15 (mean 1.748, SD 3.741). Seven patients were treated with melphalan and prednisone (MP) and 14 received 3 cycles of vincristine, BCNU, cyclophosphamide, melphalan and prednisone alternating with 3 cyles of vincristine, BCNU, doxorrubicin and dexametasone (VBCMP/VBAD). Therapy was interrupted for at least 4 weeks before the MR evaluation. Two patients under MP could not be reevaluated. One patient under VBCMP/VBAD suffered extensive L5 collapse that invalidated a second MR study. Four patients progressed under treatment and only 1 of them could be re-submitted to MR. A patient who achieved a partial response after VBCMP/VBAD refused to undergo a MR re-evaluation. Pre and post treatment MR studies were available in 14 patients (progression 1, no response 3, partial response 3, complete response 7). LWR increased in 11/14 patients (78%) (p=0.034). However, 7/7 (100%) complete responders presented a LWR increase (p=0.018) while only 4/7 (57%) non-responders did. No significant differences were observed among partial responders or patients non-responding or progressing.Conclusions. Changes i LWR as assessed by 1H NMR correlated with response to chemotherapy in patients with multiple myeloma, thus this technique may be used to measure noninvasively the response to treatment in these patients.

Aplasia medular tratada exitosamente con ciclosporina en un paciente en hemodiálisis crónica

A 28 years old male on chronic hemodialysis for 40 months due to a IgA crescentic glomerulonephritis developed pancytopenia (hematocrit 16%, white blood cell count 3,800 mm3 and platelets 11,000 mm3. The bone marrow aspirate showed erythropoietic hyperplasia. Hemolytic anemia, folate or vitamin B12 deficiency and paroxysmal nocturnal hemoglobinuria were ruled out. Steroids were given with a transient elevation of red cells and platelets, which lasted only for some weeks. Afterwards, intravenous immunoglobulin was given without benefit. Two months after, a bone marrow biopsy and a bone marrow magnetic resonance imaging showed severe aplasia. Cyclosporine was started with a rapid increase in blood cells count. Eight months later, he received a renal transplant from a cadaveric donor. Immunosupression was achieved with cyclosporine, prednisone and mycofenolate mofetil. The patient required hemodialysis for the first three weeks and a mild acute cellular rejection was treated with methylprednisolone. At discharge, 6 weeks later, serum creatinine was 2.4 mg/dl and creatinine clearance 37.6 ml/min. During the first months after transplant, platelet count and hemoglobin decreased and a bone marrow biopsy showed only mild hypoplasia. Four months after renal transplant the hematocrit was 43%, white blood cell count 6,600 mm3 and platelets, 150,000 mm3 and did not change during the first year of follow up.

608 Bone marrow magnetic resonance imaging allows objective assessment of prostate cancer (PCA) bone metastases

608 Bone marrow magnetic resonance imaging allows objective assessment of prostate cancer (PCA) bone metastases

Vertebral Body Ischemia in the Posterior Spinal Artery Syndrome

A case of posterior spinal cord syndrome in which magnetic resonance images showed predominant T2 hyperintense signal in the adjacent vertebral body is reported. To present the case for abnormal bone marrow magnetic resonance signal in the radiologic diagnosis of posterior spinal cord syndrome and to review its significance. Infarction in the region of posterior spinal arteries has been rarely described. This is attributable not only to the infrequent occurrence of infarction of posterior spinal arteries, but also to a lack of well-established diagnostic procedures. It is of clinical value to define diagnostic images of posterior spinal cord syndrome, especially early in the course of the disease. The subject was a 52-year-old man who was presented with acute nontraumatic myelopathy. Magnetic resonance imaging, performed serially after onset of the disorder from 5 hours to 11 months, was evaluated in comparison with neurologic findings. The literature was reviewed to discuss the magnetic resonance images of spinal cord infarction. The neurologic findings were consistent with posterior spinal cord syndrome. A magnetic resonance image taken at 5 hours after onset of the syndrome showed T2 hyperintense signal in the T12 vertebral body. At 3 days after onset, T2 hyperintense signal became obvious in the posterior portion of the spinal cord at T9-T12 vertebral levels. Follow-up magnetic resonance imaging at 41 days, 8 months, and 11 months showed a decrease in the size and intensity of the T2 signal change in the spinal cord and T12 vertebral body. In the literature, T2 hyperintense bone marrow signal was defined in one case of posterior spinal cord syndrome and seven cases of anterior spinal cord syndrome. Associated bone marrow abnormalities likely reflect the underlying pathology of the blood supply to the vertebral body, and may be an additional key sign for radiologic diagnosis of posterior spinal cord syndrome.

Comparison of qualitative and quantitative analyses of age‐related changes in clivus bone marrow on MR imaging

Magnetic resonance (MR) imaging is capable of detecting a wide spectrum of diseases involving clivus bone marrow. To evaluate any pathology in this region, the normal MR signal intensity patterns according to age should be known. Assessment of clivus bone marrow is usually and more efficiently made visually (qualitatively) on routine MR imaging. To compare the qualitative and quantitative analyses of age-related changes in clivus bone marrow on MR imaging, midsagittal T1-weighted MR images of the clivus bone marrow were prospectively evaluated in 201 subjects. MR signal intensity patterns of clivus bone marrow were qualitatively graded from I to III according to the proportions of low and high signal intensity areas within the clivus (Grade I: predominantly hypointense, Grade III: predominantly hyperintense). Signal intensity measurements were also made from the clivus, pons, and the cerebrospinal fluid within the fourth ventricle. Grade I pattern was observed in 92% of the subjects in the first decade, whereas Grade III pattern was not seen in this decade; Grade I pattern was absent in all but one of the subjects over the age of 50. Mean values of clivus/pons and clivus/CSF signal intensity measurements gradually increased with age in both males and females. Comparison of these ratios in each gender showed statistically significant higher values for males (P < 0.05). Comparison of the qualitative and quantitative results showed that calculated mean values of intensity ratios for each grade were different from each other; however, there was an overlap of the ranges of signal intensity ratios for Grades II and III. Visual evaluation of the clivus bone marrow MR signal is validated with the quantitative assessment results. Statistically significant higher intensity ratios in males may reflect a difference between gender in the bone mineral content under the influence of sex hormones.

Preliminary results of a bone marrow magnetic resonance imaging protocol for patients with high-risk prostate cancer

Objectives. To compare the accuracy of a bone marrow magnetic resonance imaging (MRI) protocol in patients at high risk of metastatic disease with radioisotopic bone scans, the standard method for detection of bony metastases in patients with prostate cancer. Methods. The study group consisted of 19 men with prostate cancer who underwent a bone marrow MRI between November 1993 and February 1996. This protocol images the marrow of the thoracolumbar spine, sacrum, pelvis, and femurs. Indications for MRI included an equivocal bone scan and/or staging of locally advanced or recurrent disease. The findings on MRI and bone scan were compared and the results correlated with the subsequent clinical patient outcome. Results. The bone marrow MRI protocol detected metastatic disease in 1 (7%) of 13 patients with negative bone scans. Four patients had an indeterminate bone scan: 2 had true-positive MRIs, 1 a true-negative MRI, and 1 a false-positive MRI on the basis of subsequent clinical follow-up. Two patients with positive bone scans had true-positive MRIs. Conclusions. Although not recommended for routine staging, MRI was useful in this study for clarifying an equivocal bone scan. The bone marrow MRI protocol images a high yield volume of the bony skeleton and is fast and economical compared with obtaining many focused MRI scans of these areas separately. These preliminary data suggest that further investigation of its clinical utility for staging locally advanced or recurrent disease is justified.

Prognostic significance of magnetic resonance imaging of femoral marrow in patients with myelodysplastic syndromes.

To investigate whether the abnormalities observed on femoral marrow magnetic resonance images are related to the development of leukemia and survival of patients with myelodysplastic syndromes (MDS). The findings on magnetic resonance images of the femoral marrow were evaluated over periods of 1 to 92 months (median, 18 months) in 42 consecutive adult patients with newly diagnosed MDS. Magnetic resonance images were obtained by the T1-weighted spin echo method and the short T1 inversion recovery technique. Magnetic resonance images showed that the femoral marrow patterns changed from fatty, faint, or nodular to scattered or uniform as the disease progressed. Development of acute myeloid leukemia was observed in only 13 patients whose marrow exhibited a scattered or uniform pattern. The overall survival of the 29 patients with a scattered or uniform marrow pattern was significantly shorter than that of the 13 patients with a fatty, faint, or nodular marrow pattern (10.7% v 73.3% at 7 years; P < .01). The period of leukemia-free survival was also significantly shorter in the patients with a scattered or uniform marrow pattern versus a fatty, faint, or nodular pattern (37.7% v 100% at 7 years; P < .01). Magnetic resonance images of the femoral marrow can provide valuable information for assessing the prognosis and determining the most appropriate management of patients with MDS.

Stage III multiple myeloma: clinical and prognostic value of spinal bone marrow MR imaging.

To determine the clinical and prognostic value of spinal bone marrow magnetic resonance (MR) imaging in stage III multiple myeloma. In 80 patients with untreated, newly diagnosed stage III multiple myeloma, initial MR imaging patterns of spinal bone marrow involvement were correlated with hematologic parameters and response to induction chemotherapy. The influence of these patterns on survival was studied in 57 patients who did not undergo cytotoxic therapy with stem cell transplantation. MR imaging patterns of marrow involvement were normal in 19 (24%) patients, focal in 35 (44%), and diffuse in 26 (32%). Patients with the diffuse pattern had higher marrow plasmacytosis (P < or = .003) and cellularity (P < or = .001), higher serum calcium (P < or = .005) and beta 2-microglobulin (P < or = .008) levels, and lower hemoglobin values (P < or = .001) than did those with the normal or focal patterns. Patients with the normal pattern responded better to therapy (P = .007) and survived longer than patients with an abnormal pattern (P = .026). MR imaging findings and C-reactive protein level were the best independent prognostic indicators of survival. MR imaging patterns of spinal bone marrow involvement are correlated with several clinical parameters of disease severity and have prognostic value in stage III multiple myeloma.

Bone Marrow Involvement in Lymphoma: The Importance of Marrow Magnetic Resonance Imaging

Detection of bone marrow involvement is important for staging and treatment decisions in patients with lymphoma. Although routine bone marrow evaluation is based on aspirates and bone marrow biopsies, new diagnostic tools are required to improve diagnostic accuracy. Visual and quantitative assessment of the bone marrow by magnetic resonance (MR) imaging is useful for the detection of occult lymphomatous marrow involvement. MRI is also suitable for the evaluation of disease extent in the bone marrow. Furthermore, abnormal images on marrow MRI may be associated with a significantly poorer survival in patients with lymphoma, regardless of histologic findings in the marrow. Evaluation of the bone marrow by MRI is essential to assess disease status in patients with lymphoma.