Magnetic resonance imaging of disseminated bone marrow disease in patients treated for malignancy

The T1 Ratio of Marrow (TROM) as a Novel Tool to Identify Metastatic from Nonmalignant Marrow Lesions of the Spine: A Pilot Study

Objective  The purpose of this study was to analyze quantitative values of normal and abnormal marrow on T1-weighted images of spine, to propose a ratio for T1 values of abnormal to normal vertebrae, and to assess whether this ratio could be helpful in predicting presence of neoplastic lesions in the spine. Materials and Methods  One-hundred randomly selected magnetic resonance imagings of lumbar spine without infection, fracture, and tumor were selected to form normal cohort. A second cohort of 100 metastasis of lumbar spine was identified. Ratio of T1 value of vertebral body to the T1 value of the inferior vertebral body was performed for normal cohort from D11 to L5. Ratio of T1 value of metastasis to adjacent normal vertebral body was done for metastatic cohort. Data was analyzed using standard t -test and kappa was performed for intra- and inter-observer reliability. Results  A decline in T1 value of abnormal to normal marrow was seen in patients with metastasis that was statistically significant. We call this the T1 ratio of marrow (TROM). The sensitivity and accuracy with the cutoff value of TROM at 0.7 (92% sensitivity, 97.1% accuracy) are better than at 0.6 (75% sensitivity, 96.2% accuracy) or 0.5 (47% sensitivity, 93.2% accuracy). A subset analysis of the other T1 hypointense benign lesions including atypical hemangiomas and focal marrow hyperplasia, however, revealed overlapping TROM values with the metastatic cohort. Conclusion  Using the TROM on T1-weighted images could not confidently differentiate malignant from benign T1 hypointense lesions of the spine.

Development and validation of MRI-based radiomics signatures as new markers for preoperative assessment of EGFR mutation and subtypes from bone metastases

Background

This study aimed to develop and externally validate contrast-enhanced (CE) T1-weighted MRI-based radiomics for the identification of epidermal growth factor receptor (EGFR) mutation, exon-19 deletion and exon-21 L858R mutation from MR imaging of spinal bone metastasis from primary lung adenocarcinoma.

Methods

A total of 159 patients from our hospital between January 2017 and September 2021 formed a primary set, and 24 patients from another center between January 2017 and October 2021 formed an independent validation set. Radiomics features were extracted from the CET1 MRI using the Pyradiomics method. The least absolute shrinkage and selection operator (LASSO) regression was applied for selecting the most predictive features. Radiomics signatures (RSs) were developed based on the primary training set to predict EGFR mutations and differentiate between exon-19 deletion and exon-21 L858R. The RSs were validated on the internal and external validation sets using the Receiver Operating Characteristic (ROC) curve analysis.

Results

Eight, three, and five most predictive features were selected to build RS-EGFR, RS-19, and RS-21 for predicting EGFR mutation, exon-19 deletion and exon-21 L858R, respectively. The RSs generated favorable prediction efficacies for the primary (AUCs, RS-EGFR vs. RS-19 vs. RS-21, 0.851 vs. 0.816 vs. 0.814) and external validation (AUCs, RS-EGFR vs. RS-19 vs. RS-21, 0.807 vs. 0.742 vs. 0.792) sets.

Conclusions

Radiomics features from the CE MRI could be used to detect the EGFR mutation, increasing the certainty of identifying exon-19 deletion and exon-21 L858R mutations based on spinal metastasis MR imaging.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09985-4.

False Negativity of Tc-99m Labeled Sodium Phytate Bone Marrow Imaging Under the Effect of G-CSF Prescription in Aplastic Anemia: A Case Report

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic cytokine which controls the differentiation and growth of hematopoietic cells in the bone marrow. We report a severe aplastic anemia (SAA) patient with false-negative ^99mTc sodium phytate bone marrow imaging findings under concurrent G-CSF therapy. The first bone marrow imaging showed a normal bone marrow activity. However, the bone marrow biopsy pathology report revealed a lack of hematopoietic cells. Furthermore, the complete blood count indicated severe pancytopenia resulting in the diagnosis of aplastic anemia (AA). A second marrow scan implemented after the stoppage of G-CSF showed an abnormal bone marrow activity, which matched the pathology reports. Accordingly, the concurrent administration of G-CSF was considered as the cause of false-negative bone marrow imaging findings obtained in the first scan. Consequently, it should be kept in mind that a ^99mTc sodium phytate bone marrow scintigraphy during the concurrent administration of G-CSF may lead to the achievement of false negative results because it induces changes in bone marrow mimicking a normal marrow scan in patients with AA.

Is routine MRI necessary to exclude pathological fractures in patients with an oncological history?

INTRODUCTION

Magnetic resonance imaging (MRI) is the radiological modality of choice for diagnosing pathological fractures in situations of diagnostic uncertainty. With the increasing availability of MRI, we have observed a disturbing trend in utilising routine MRI scans to exclude pathological fractures in all patients with a history of cancer. The study objective was to determine if routine use of MRI scans in such patients is truly necessary and if other predictive factors can be utilised in lieu of the MRI scan.

MATERIALS AND METHODS

A 3-year retrospective study was conducted reviewing all extremity MRI scans performed for suspected pathological fractures and compared to X-rays. All patients presented with an extremity fracture, a known diagnosis of solid organ cancer and had an MRI to determine if the fracture was pathological. Subjects were followed up with serial X-rays up to 1 year.

RESULTS

84 subjects were recruited. Comparing X-rays alone with MRI scans revealed 92% sensitivity and 98% specificity in detecting pathological fractures. Using X-rays in combination with an absent history of trauma increases the sensitivity to 100% but reduced the specificity to 91%. None of subjects in cancer remission had pathological fractures.

CONCLUSIONS

MRI is an imperative tool for operative planning in pathological fractures; however, we recommend against the routine use of MRI to diagnose pathological fractures in oncological patients. Patients with solid organ cancer remission, a positive history of significant trauma prior to sustaining the fracture, and the absence of pathological features on plain radiographs are strongly predictive against pathological fractures.

Skeletal Metastasis-an Epidemiological Study

Metastasis is the commonest bone tumors. The commonest primary metastasis to the bone are the breast, lung, prostate, kidney, and thyroid. The bone is the third common site of metastatic disease, only the lung and the liver have higher metastatic rate than skeleton. We have no epidemiological studies conducted to evaluate the various aspects of skeletal metastasis like age, sex distribution, presentation, common sites of primary and associated secondary metastases, and investigation from Indian subcontinent. Here we are presenting the first epidemiological study of skeletal metastasis from our region. We have conducted a prospective descriptive study in the Departments of Orthopedics and Radiotherapy, Government Medical College, Kozhikode, during the period of 2007 to 2009. One hundred eleven patients were included in the study above the age of 30 years. Clinical examination and investigation were done on these patients. Skeletal metastasis commonly occurs in the fifth decade of life with modest male preponderance. In most of the cases, the primary site of malignancy was undetected at the time of presentation. Pain was the commonest presented complaint of the patient. The spine is the commonest site affected and the lung was the common site of primary metastasis. Most of the cases were detected by radiogram and confirmation was obtained by minimally invasive technique like FNAC or CNB.

Proton density fat fraction (PDFF) MRI for differentiation of benign and malignant vertebral lesions

OBJECTIVES

To investigate whether proton density fat fraction (PDFF) measurements using a six-echo modified Dixon sequence can help to differentiate between benign and malignant vertebral bone marrow lesions.

METHODS

Sixty-six patients were prospectively enrolled in our study. In addition to conventional MRI at 3.0-Tesla including at least sagittal T2-weighted/spectral attenuated inversion recovery and T1-weighted sequences, all patients underwent a sagittal six-echo modified Dixon sequence of the spine. The mean PDFF was calculated using regions of interest and compared between vertebral lesions. A cut-off value of 6.40% in PDFF was determined by receiver operating characteristic curves and used to differentiate between malignant (< 6.40%) and benign (≥ 6.40%) vertebral lesions.

RESULTS

There were 77 benign and 44 malignant lesions. The PDFF of malignant lesions was statistically significant lower in comparison with benign lesions (p < 0.001) and normal vertebral bone marrow (p < 0.001). The areas under the curves (AUC) were 0.97 for differentiating benign from malignant lesions (p < 0.001) and 0.95 for differentiating acute vertebral fractures from malignant lesions (p < 0.001). This yielded a diagnostic accuracy of 96% in the differentiation of both benign lesions and acute vertebral fractures from malignancy.

CONCLUSION

PDFF derived from six-echo modified Dixon allows for differentiation between benign and malignant vertebral lesions with a high diagnostic accuracy.

KEY POINTS

• Establishing a diagnosis of indeterminate vertebral lesions is a common clinical problem • Benign bone marrow processes may mimic the signal alterations observed in malignancy • PDFF differentiates between benign and malignant lesions with a high diagnostic accuracy • PDFF of non-neoplastic vertebral lesions is significantly higher than that of malignancy • PDFF from six-echo modified Dixon may help avoid potentially harmful bone biopsy.

Assessment of bone marrow involvement in patients with lymphoma: report on a consensus meeting of the Korean Society of Hematology Lymphoma Working Party

In September 2011, the Korean Society of Hematology Lymphoma Working Party held a nationwide conference to establish a consensus for assessing bone marrow (BM) involvement in patients with lymphoma. At this conference, many clinicians, hematopathologists, and diagnostic hematologists discussed various topics for a uniform consensus in the evaluation process to determine whether the BM is involved. Now that the discussion has matured sufficiently to be published, we herein describe the consensus reached and limitations in current methods for assessing BM involvement in patients with lymphoma.

The Correspondence Between Magnetic Resonance Images and the Clinical and Intraoperative Status of Patients with Spinal Tumors

ABSTRACT INTRODUCTION

Surgical treatment of tumors, particularly metastases to the spine, has become increasingly common owing to the progress in anesthesiology and spinal surgery and greater detectability. The patients qualified for surgeries are those with mechanical pain, fracture or at risk of vertebral fracture or neurological complications. The basis for qualification for different types of surgeries is clinical and imaging examination, particularly MRI and CT. Qualification should always be multidisciplinary and requires understanding and knowledge of its most essential aspects. When carrying out imaging examinations, it is necessary to assess the size and the type of the tumor, taking into account of differential diagnosis. One should also consider the factors indicating spinal instability or the onset of neurological deficits. The criteria developed by Kostiuk-Weinstain and Taneichi are used for that purpose. The aim of the present study was to evaluate the correspondence between the most essential elements of clinical and MRI examination of the spine and the intraoperative status of patients with spinal tumors.

MATERIALS AND METHODS

We carried out prospective examination assessing the correspondence between the clinical status and MR images and the intraoperative spine. We introduced algorithm to describe the morphology of neoplastic lesions within the spine.

RESULTS

The information obtained from the clinical examination and the intraoperative status of the spine corresponded with the MRI examination with the exception of the assessment of neoplastic infiltration to soft tissues, dura mater and nerve roots. It was also found that there are no clear-cut MRI features allowing differentiation of metastatic lesions from primary tumors and osteitis. Furthermore, MRI examination does not allow for the assessment of the quality of bone tissue in the vicinity of the tumor.

Comparison of [18 F]FDG PET/CT and MRI in the diagnosis of active osteomyelitis

OBJECTIVE

In diagnosing osteomyelitis (OM) both MRI and [18 F]FDG PET-CT proved to be accurate modalities. In anticipation of the advent of hybrid PET/MRI scanners we analyzed our patient group to give direction to future imaging strategies in patients with suspected OM.

MATERIALS AND METHODS

In this retrospective study all patients of a tertiary referral center who underwent both an MRI and a PET for the diagnosis of OM were included. The results of those scans were evaluated using patient's histology, microbiological findings, and clinical/radiological follow-up. Additionally, ROC curve analysis of the SUVmax and the SUVmax ratio on the PET scans was performed. Two imaging strategies were simulated: first MRI followed by PET, or vice versa.

RESULTS

Twenty-seven localizations in 26 patients were included. Both MRI and PET were shown to be accurate in our patients for the qualitative detection of OM. A cut-off value for the SUVmax of 3 gave optimal results (a specificity of 90 % with a sensitivity of 88 %). The SUVmax ratio gave a worse performance. The two simulated imaging strategies showed no difference in the final diagnosis in 20 out of 27 cases. Remarkably, 6 equivocal cases were all correctly diagnosed by the second modality, i.e., PET or MRI.

CONCLUSION

Both MRI and [18 F]FDG PET were accurate in diagnosing OM in a tertiary referral hospital population. Simulation of imaging strategies showed that a combined sequential strategy was optimal. It seems preferable to use MRI as a primary imaging tool for uncomplicated unifocal cases, whereas in cases with (possible) multifocal disease or a contraindication for MRI, PET is preferred. This combined sequential strategy looks promising, but needs to be confirmed in a larger prospective study.

MRI of spinal bone marrow: part I, techniques and normal age-related appearances

OBJECTIVE

This article reviews MRI protocols, including routine and nonroutine pulse sequences as well as the normal MRI appearance of spinal marrow and expected age-related changes.

CONCLUSION

Routine MRI of the spine provides useful evaluation of the spinal bone marrow, but nonroutine MRI pulse sequences are increasingly being used to evaluate bone marrow pathology. An understanding of MRI pulse sequences and the normal and age-related appearances of bone marrow is important for the practicing radiologist.

Imaging of spinal metastatic disease

Metastases to the spine can involve the bone, epidural space, leptomeninges, and spinal cord. The spine is the third most common site for metastatic disease, following the lung and the liver. Approximately 60-70% of patients with systemic cancer will have spinal metastasis. Materials/Methods. This is a review of the imaging techniques and typical imaging appearances of spinal metastatic disease. Conclusions. Awareness of the different manifestations of spinal metastatic disease is essential as the spine is the most common site of osseous metastatic disease. Imaging modalities have complimentary roles in the evaluation of spinal metastatic disease. CT best delineates osseous integrity, while MRI is better at assessing soft tissue involvement. Physiologic properties, particularly in treated disease, can be evaluated with other imaging modalities such as FDG PET and advanced MRI sequences. Imaging plays a fundamental role in not only diagnosis but also treatment planning of spinal metastatic disease.

NCCN Task Force Report: Bone Health in Cancer Care

Bone health and maintenance of bone integrity are important components of comprehensive cancer care in both early and late stages of disease. Risk factors for osteoporosis are increased in patients with cancer, including women with chemotherapy-induced ovarian failure, those treated with aromatase inhibitors for breast cancer, men receiving androgen-deprivation therapy for prostate cancer, and patients undergoing glucocorticoid therapy. The skeleton is a common site of metastatic cancer recurrence, and skeletal-related events are the cause of significant morbidity. The National Comprehensive Cancer Network (NCCN) convened a multidisciplinary task force on Bone Health in Cancer Care to discuss the progress made in identifying effective screening and therapeutic options for management of treatment-related bone loss; understanding the factors that result in bone metastases; managing skeletal metastases; and evolving strategies to reduce bone recurrences. This report summarizes presentations made at the meeting.

Magnetic resonance imaging of bone marrow in oncology, Part 2

Magnetic resonance imaging plays an integral role in the detection and characterization of marrow lesions, planning for biopsy or surgery, and post-treatment follow-up. To evaluate findings in bone marrow on MR imaging, it is essential to understand the normal composition and distribution of bone marrow and the changes in marrow that occur with age, as well as the basis for the MR signals from marrow and the factors that affect those signals; these points have been reviewed and illustrated in part 1 of this two-part article. Part 2 will emphasize the practical application of MR imaging to facilitate differentiation of normal marrow, tumor, and treatment-related marrow changes in oncology patients, and will review complementary MR techniques under development.

Prostate cancer metastases to bone: pathophysiology, pain management, and the promise of targeted therapy

Bone metastases are a significant cause of pain and morbidity in prostate cancer, especially if they lead to complications such as pathological fractures and spinal cord compression. Palliation of pain can be achieved with radiation, radioisotopes, hormone therapy, chemotherapy, and bisphosphonates. Bisphosphonates also reduce the risk of skeletal complications. Studies with animal models and advances in understanding the molecular basis for bone metastases have yielded new targets for therapy. Some of the promising therapeutic trials are reviewed in this paper.

Acute lymphoblastic leukemia of the skin and subcutaneous tissues; the first manifestation of disease in a 6-month-old infant: a case report with literature review

Leukemic infiltrate involving the skin and subcutaneous tissue was the first manifestation of disease in a 6-month-old female infant. Knowledge of age-related distribution patterns of the red (cellular) and yellow (fatty) marrow is crucial for the interpretation of magnetic resonance imaging (MRI) studies. Diffusely decreased signal intensity throughout the bone marrow on the T1-weighted images specifically involving the epiphyseal ossification centers in infants 6 months after their appearance should be suggestive of a marrow infiltrative/replacement process. Correlation with the peripheral blood smear and bone marrow aspirate are necessary for the diagnosis of leukemia.

MRI of bone metastases: the choice of the sequence

MRI is very sensitive to detect bone metastases. To improve specificity, a clever use of sequences, spin echo, gradient echo in or opposed phase, contrast medium and diffusion is needed.

Comparative whole-body 201Tl and bone scintigraphies for the detection of bone marrow involvement in multiple myeloma

The objectives of this study were to investigate the role of whole-body 201Tl-chloride scintigraphy in comparison with bone scintigraphy in the detection of bone marrow involvement in patients with multiple myeloma and to assess the follow-up evaluation using 201Tl-chloride. Twenty-one patients with untreated multiple myeloma were evaluated. 201Tl-chloride images were acquired 10 min (early) and 2 h (delayed) after the injection of 111 MBq 201Tl-chloride. Bone images were acquired 3 h after the intravenous injection of 740 MBq 99mTc-hydroxymethylene diphosphonate (HMDP). The 201Tl-chloride scan patterns were classified as normal, diffuse (presence of bone marrow), focal (localized areas of uptake) and diffuse+focal. The bone scan patterns were classified as normal and abnormal. Eight of the 21 patients also underwent 201Tl-chloride scintigraphy after chemotherapy for the evaluation of the therapeutic response. On the early 201Tl-chloride image, two patients showed a normal, 13 a diffuse, two a focal and four a diffuse + focal pattern. On the delayed 201Tl-chloride image, nine patients showed a normal, six a diffuse, four a focal and two a diffuse + focal pattern. Bone scintigraphy showed an abnormal accumulation in only five of the 21 patients. Of the eight patients who underwent follow-up 201Tl-chloride studies, the abnormal diffuse pattern was changed to a normal pattern on post-treatment scintigraphy in three, and the degree of abnormal 201Tl-chloride accumulation decreased in comparison with the pre-treatment scan in three. These six patients were considered to be in clinical remission. In the two remaining patients, the degree of abnormal 201Tl-chloride accumulation increased in comparison with the pre-treatment scan, and they were considered to be in clinical progression. 201Tl-chloride scintigraphy is a non-invasive tool, which may be more useful than bone scintigraphy for the diagnosis of multiple myeloma, and may be helpful in the follow-up of multiple myeloma.

Detection of minimal residual disease in acute leukemia by Tc-99m MIBI femoral marrow imaging

To determine the potential of Tc-99m MIBI femoral marrow imaging for detecting minimal residual disease in acute leukemia, MIBI images of 68 patients with acute leukemia and 110 control patients were examined. MIBI accumulation was classified into three patterns: not detectable, mild accumulation, and clearly visualized accumulation. Clearly visualized accumulation was interpreted as abnormal. The mean uptake ratio of the femoral marrow to muscle was calculated. Forty-five patients who were in complete remission (CR) at the time of MIBI imaging had a follow-up study (mean interval, 23 months). Clearly visualized accumulation was demonstrated in 35 patients with acute leukemia: in 7 patients before starting induction chemotherapy, in 12 patients after relapse, and in 16 of the 49 patients in the CR group. Mild accumulation was demonstrated in 14 patients in the CR group and in 13 control group patients. No detectable accumulation was observed in 19 patients in the CR group and in 97 control patients. The marrow and muscle uptake ratio of patients before starting chemotherapy (2.29 +/- 0.26) was greater compared with that in patients after relapse (1.78 +/- 0.44, P < 0.02) and in patients with abnormal accumulation despite complete remission (1.84 +/- 0.36, P < 0.01). The uptake ratio in patients with abnormal accumulation despite CR was higher compared with patients with mild accumulation in CR (1.26 +/- 0.13, P < 0.001) and controls (1.23 +/- 0.10, P < 0.001) who had mild accumulation. Fifteen patients with abnormal accumulation despite CR had a markedly greater relapse rate (66.7% > 10.0%, P < 0.005), a higher mortality rate (46.7% > 6.7%, P < 0.01), and shorter remission time (8.7 +/- 10.2 months < 35.9 +/- 20.1 months, P < 0.001) compared with 30 patients without abnormal accumulation in CR. MIBI femoral marrow imaging may be a useful and simple method for monitoring levels of residual leukemic cells. Clearly visualized MIBI accumulation may be a marker for relapse.

Diagnostic investigations in cancer pain

Defining the specific cause of pain in patients with cancer often has substantial therapeutic and prognostic implications. This process often requires the use of specific diagnostic investigations. Here we critically review the diagnostic investigations used in the evaluation of common pain problems in patients with cancer. Familiarity with this information facilitates the development of efficient and rational diagnostic strategies.

Skeletal complications in pediatric oncology patients

Pediatric oncology patients are at risk for the development of numerous skeletal complications, and radiologic studies are important in the identification and evaluation of these conditions. Methotrexate osteopathy manifests as osteopenia, dense provisional zones of calcification, pathologic fractures, and sharply outlined epiphyses. Hypertrophic osteoarthropathy may occur with nasopharyngeal carcinoma or tumors of the lungs or pleura and manifests as cortical thickening, lamellar periosteal new bone formation, and soft-tissue swelling. Biomechanical abnormalities are often seen at bone scintigraphy in patients who have undergone surgery for bone tumors. Growth plate injury may manifest as marked deformity, sclerotic metaphyseal bands, metaphyseal fraying, and longitudinal striations. Radiation "osteitis" is seen as an initial decrease in bone density with subsequent development of a mixed radiolucent and sclerotic appearance. Ischemic necrosis of the femoral heads is best demonstrated at magnetic resonance (MR) imaging and has low signal intensity on T1-weighted images and a high-signal-intensity rim on T2-weighted images. Bone infarcts are seen as well-demarcated, often ring-shaped areas of decreased signal intensity on T1-weighted MR images and as areas of increased signal intensity on short-inversion-time inversion recovery images. Radiographic signs of infection include bone destruction, periosteal new bone formation, and sclerotic changes. Short-inversion-time inversion recovery MR imaging is particularly useful in evaluating posttherapy changes in bone marrow. Osteochondroma may demonstrate a cartilaginous cap at MR imaging, whereas the most important finding in radiation-induced sarcoma is a soft-tissue mass. Radiologists who work with children with cancer need to be familiar with these complications and their imaging appearances.

Tc-99m MIBI localization in bone marrow: a marker of bone marrow malignancy

To determine the potential of Tc-99m MIBI for detecting bone marrow malignancy, MIBI imaging of the femur was evaluated. There was no detectable MIBI activity in 125 of 141 (89%) control patients. Clearly demonstrated focal or tubular MIBI activity indicating intramedullary accumulation was demonstrated in 44 of 45 (98%) patients with proven marrow malignancy: 9 patients with multiple myeloma, 10 patients with malignant lymphoma, 11 patients with acute leukemia, 1 patient with chronic leukemia, and 14 patients with skeletal metastases. No abnormal MIBI activity was observed in the femur in 19 of 22 (86%) patients who had no evidence of malignant involvement in the femoral marrow, in 3 patients with solitary plasmacytomas of the spine, sternum or iliac bone, or in 16 patients with malignant lymphoma. In 12 of 24 patients with acute leukemia in complete remission, no abnormal MIBI accumulation was shown in the femur, but in 12 patients, abnormal accumulation indicating residual leukemic activity was demonstrated. MIBI imaging correlated extremely well with MRI studies; 26 of 28 patients with focal or tubular increased MIBI activity in the femur showed decreased signal on T1-weighted images and a high signal on short inversion recovery images, and 11 patients with no abnormal activity showed a high signal on T1 images. MIBI imaging of the femoral bone marrow may be a new modality for detecting marrow malignancy.

Magnetic resonance imaging of the bone marrow in lymphomas and leukemias

This article reviews MRI techniques and results in the assessment of bone marrow in patients with lymphoma. MRI is more sensitive than blind biopsy (BB) in detecting bone marrow invasion. False-negative results have been reported in low-grade non Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia. Bone marrow imaging is particularly indicated in patients with Hodgkin's disease, high grade NHL or myelocytic leukemia, with a negative BB and abnormal clinical (stage B, bone pains) or biochemical data (elevated alkaline phosphatase) and who have relapsed. During treatment. MR imaging is a valuable tool for the evaluation of response and the diagnosis of benign bone marrow complications. Knowledge of post-therapeutic patterns is essential to avoid misinterpretations. The main drawback with this technique is its inability to differentiate residual lesions from fibrosis and needle guided-biopsy is mandatory if treatment decision-making relies on the MR result, alone.

Initial experience with dynamic MR imaging in evaluation of normal bone marrow versus malignant bone marrow infiltrations in humans

The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio.

Bone scintigraphy and multimodality imaging in bone neoplasia: strategies for imaging in the new health care climate

The integration of multiple imaging modalities in the assessment of musculoskeletal neoplasia is complex. Although no two instances are identical, certain guidelines can be gleaned from our experience as well as that reported in the literature. Assessment of most soft tissue masses is best carried forth with a combination of conventional radiography and magnetic resonance imaging (MRI). Screening skeletal scintigraphy without localizing symptomatology that includes axial and appendicular skeleton is best carried out initially with bone scintigraphy. Screening the axial skeleton in the presence of clinical symptomatology or a strong suspicion of axial skeletal metastases or pathology is best implemented as a total spine screening examination with MRI and specialized pulsing sequences. Computed tomography is reserved primarily for assessment of cortical and juxtacortical lesions, fracture fragment positioning and/or configuration, and characterization of lesion matrix calcification or ossification when conventional radiographs are indeterminate. Although physical examination and conventional radiography still remain the initial medical algorithms used to evaluate possible musculoskeletal neoplasia, primary skeletal tumors may require multimodality imaging to segregate aggressive and nonaggressive processes. In this multimodality scenario, bone scintigraphy has a critical role in assisting with differentiation between malignant and benign neoplasms.

Evaluation of suspected musculoskeletal neoplasms using 3D T2-weighted spectral presaturation with inversion recovery

This study evaluated the use of the Spectral presaturation with inversion recovery (SPIR) technique with T2-weighting in 43 pathologically proven cases of suspected musculoskeletal neoplasm. Both primary and secondary malignant neoplasms as well as benign neoplasms were studied. The MR features exhibited by this technique are discussed. The images were evaluated by two experienced MRI specialists and graded as to utility into one of four categories as compared to conventional T1- and T2-weighted sequences. In the majority of cases this technique was found to be helpful or extremely helpful. The most useful features of this technique were the elimination of chemical shift artifact, the improved ability to evaluate superficial lesions or the extension of lesions into subcutaneous fat, and substantially improved visualization of both bone marrow and bone cortex interfaces. T2-weighted, fat suppressed imaging proved to be a useful new tool for evaluating musculoskeletal neoplasms.

Bone marrow after autologous blood stem cell transplantation and total body irradiation: magnetic resonance and chemical shift imaging

Magnetic resonance studies of the lumbar, pelvic, and femoral bone marrow were performed in 10 patients after autologous blood stem cell transplantation, including total body irradiation and myeloablative chemotherapy. The posttreatment interval varied between 2 and 6 yr. The appearance on T1-weighted images and the quantitative data obtained from chemical shift imaging (relative fat signal) were compared to 10 age-matched healthy volunteers. The classification of the T1-weighted images yielded no significant differences between the two groups. Chemical shift imaging by determination of the relative fat signal was able to detect a significant fatty replacement of the patients' lumbar (p < .002) and pelvic marrow (p < .01), showing the clinically inapparent decreased cellularity of the bone marrow. This difference did not change within the interval of 2-6 yr after transplantation.