Bone marrow patterns in aplastic anemia: observations with 1.5-T MR imaging

Six patients diagnosed as having aplastic anemia underwent magnetic resonance (MR) imaging. The bone marrow in the lumbar spine, pelvis, and proximal femora was examined in each case. One patient had a normal marrow signal intensity (SI) and pattern and was considered cured of disease. The other patients had varying numbers of focal low-SI areas interspersed with high-SI areas in the marrow of the spine. The pelves and proximal femora of all patients had diffuse high-SI marrow without focal abnormalities. Biopsy of a lumbar vertebral body in one patient demonstrated that the focal low-SI areas may have been islands of active hematopoietic cells scattered in otherwise fatty marrow. MR may prove to be a valuable, noninvasive method of following the response of patients with aplastic anemia to therapy; more investigation is necessary before this can be definitely concluded.     

Fungal pulmonary infections after bone marrow transplantation: evaluation with radiography and CT

The authors reviewed 55 pairs of chest radiographs and computed tomographic (CT) studies obtained in 33 febrile bone marrow transplant (BMT) recipients. The images were read separately, without knowledge of the clinical diagnosis. Twenty-one episodes of fungal infection were documented. One chest radiograph showed a pneumonia-like opacity, and 17 showed nodular opacities, five with cavitation. In 20 of 21 episodes, CT showed nodules with cavitation (n = 7), halo (n = 4), hazy margin (n = 5), air bronchogram (n = 2), cluster of fluffy nodules (n = 1), or sharp margin (n = 1). In none of the nine bacteremic episodes, however, were there opacities on chest radiographs or CT studies. CT studies demonstrating complicated nodules in febrile BMT patients strongly suggest a fungal infection, whereas negative CT studies suggest bacteremia or non-filamentous fungal infection of nonpulmonary origin. CT appears to add useful information to radiographic analysis during the assessment of febrile episodes in BMT patients, especially when invasive diagnostic procedures pose a high risk.     

I-131 MIBG imaging after bone marrow transplantation for neuroblastoma.

Thirty-one children with stage III and IV neuroblastoma were studied with iodine-131 metaiodobenzyl-guanidine (MIBG) scintigraphy, technetium-99m medronate scintigraphy, skeletal plain radiography, and computed tomography (CT) before and after bone marrow transplantation (BMT). Twenty-six pre-BMT and 90 post-BMT studies were reviewed. Fourteen patients were alive without tumor, and one patient died at 4 months while free of tumor. I-131 MIBG scans obtained before and after BMT were negative in eight of the 15 patients. Seven had positive I-131 MIBG scans obtained before BMT that became negative after BMT. Six of 15 patients had small, questionable lesions on CT scans of the chest or abdomen that never increased in size, and the I-131 MIBG scans remained negative. Sixteen children had progressive disease or relapse, including four in whom I-131 MIBG scans showed new abnormalities, four with persistently positive I-131 MIBG scans, and three who had negative I-131 MIBG scans at relapse. Two of the 16 patients initially had small lesions seen on abdominal CT scans that were not seen on I-131 MIBG scans; mass lesions were later seen at CT in these locations. Detectable I-131 MIBG uptake in abdominal and thoracic lesions was related to the diameter of the lesion. Both I-131 MIBG scintigraphy and CT should be used to evaluate patients with neuroblastoma who have undergone BMT.     

Pulmonary infections following bone marrow transplantation: high-resolution CT findings in 35 paediatric patients

PURPOSE: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT. PATIENTS AND METHODS: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n=16), bacteria (n=9), fungi (n=9), and protozoa (n=1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus. RESULTS: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The "halo sign" (n=5) was seen only in patients with fungal pneumonia. CONCLUSION: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and "halo sign" are more common in patients with fungal infections.     

Second allogenic bone marrow transplantation after late graft rejection in a patient with severe aplastic anemia

Allogeneic bone marrow transplantation (BMT) is the treatment of choice in young patients (pts) with severe aplastic anemia (SAA) who have an HLA identical sibling donor. Late graft rejection to following allogeneic BMT for SAA is a significant clinical problem and is associated with a high risk of mortality. The optimal treatment strategy for patients with late graft rejection after first BMT is still an open question. We report 12-year-old patient with acquired SAA who underwent BMT from his HLA identical sister. BMT was first-line treatment within 3 months of diagnosis. Preparative therapy was Cyclophosphamide (Cy) 200 mg/kg body mass (BM) during 4 days. Graft versus host disease (GVHD) was prevented with Methotrexate (MTX), Methylprednisolone (MPDN) and Cyclosporin A (CsA). After 17 months, during which patient was with normal blood counts and full donor chimaerism, graft rejection occurred. The patient was re-engrafted from the same donor after conditioning with Cy 200 mg/kg BM plus horse antithymocyte globulin (ATG)--2 vials (á 25 mg)/10 kg BM over 4 days. Before the collection, donor's bone marrow was activated with low dose rhGM-CSF (3 micrograms/kg one day). Following a secondary BMT engraftment has sustained. The patient is alive with full donor chimaerism 26 months from secondary transplantation, without acute or chronic GVHD.     

Serum thymidine kinase,a possible marker for monitoring the effect of bone marrow transplant treatment in early recovery phase

We measured serum thymidine kinase (TK) activity with a radioenzyme assay system employing [I-125]-iododeoxyuridine as the tracer on serial specimens from five bone marrow transplant (BMT) patients before and after transplantation. The serum level of TK activity in the 4 patients with effective BMT treatment ranged from 3.0 to 16.9 U/L (mean, 7.80 U/L) before transplantation and from 27.3 to 236.1 U/L (mean, 82.95 U/L) after the BMT treatment. Mean serum TK activity increased 13.17-fold (range, 1.68 to 29.14-fold). In contrast, the activity in the patient with ineffective BMT treatment was not significantly different during, before, or after BMT treatment. In addition, serum TK activity in BMT patients was well correlated with the change in the number of leukocytes before and after BMT treatment [r = +0.709 (p less than 0.01), y = 0.012 x +0.87]. We conclude that the determination of serum TK activity in BMT patients is very useful in monitoring the course of bone marrow transplantation in the early recovery phase.     

Total lymphoid irradiation and total body irradiation for allogeneic bone marrow transplantation in aplastic anemia

Between April 1980 and June 1989, 15 patients with severe aplastic anemia (SAA) were treated at Hyogo College of Medicine with bone marrow transplantation (BMT) after preparation consisting of cyclophosphamide (CY) and total lymphoid irradiation (TLI) or total body irradiation (TBI) for the purpose of reducing the incidence of graft rejection. All patients had initial evidence of engraftment after the first transplantation except for one patient who died of heart failure due to CY on the third day after transplantation and could not be evaluated for engraftment. Rejection later occurred in four of these 14 patients, who then underwent successful regrafting. One of these patients, who was conditioned with CY alone at the first grafting, underwent successful regrafting after a conditioning regimen of CY and TBI. In the other three patients, irradiation was performed twice as the conditioning regimen. Thus, 14 of 15 patients underwent successful BMT and are alive with restored hematopoietic function. From the above results, the combination of TLI or TBI and CY was considered to be very useful as a conditioning regimen for BMT in patients with SAA.     

Carotid perfusion CT with balloon occlusion and acetazolamide challenge test: feasibility

Carotid balloon test occlusion (BTO) is used to assess the collateral circulation and cerebrovascular reserve in patients in whom carotid artery occlusion is contemplated. Eight patients in whom the test was successful were evaluated with perfusion computed tomography (CT) in the resting state and after acetazolamide challenge. Three of the patients showed symmetric blood flow and normal response to acetazolamide. One of them underwent permanent carotid occlusion and did not develop any delayed ischemic stroke. The remaining five patients showed asymmetric blood flow. One of them had markedly low blood flow and abnormal response to acetazolamide. The patient developed ipsilateral hemispheric stroke following permanent carotid occlusion after the superficial temporal artery to middle cerebral artery bypass graft occluded. In the other four patients, the steal phenomenon was seen in ipsilateral and contralateral hemispheres. Although definitive quantitative values for perfusion CT are not yet standardized, it may be feasible to predict that the patients with symmetric blood flow and normal acetazolamide-enhanced challenge test results will do well after permanent carotid occlusion. Patients with asymmetric blood flow and abnormal response to the acetazolamide challenge test may require a revascularization procedure to protect them from delayed ischemic stroke.     

S-MRI score: A simple method for assessing bone marrow involvement in Gaucher disease

Semi quantitative MRI is a very useful procedure for evaluating the bone marrow burden (BMB) in Gaucher disease (GD). Score systems have been applied to obtain a parameter for evaluating the severity of bone disease. Our purpose was to test a simple, reproducible and accurate score to evaluate bone marrow involvement in GD patients. MRI was performed in spine, pelvis and femora at diagnosis in 54 adult GD1 patients, 61.1% of whom were female. Three MRI patterns and punctuation in each location were defined: normal, 0; non-homogeneous infiltration subtypes reticular, 1; mottled, 2; diffuse, 3; and homogeneous infiltration, 4. This score was called Spanish-MRI (S-MRI). Two independent observers applied the S-MRI and bone marrow burden score and compared the differences using the non-parametric Mann-Whitney test. Correlation rank test was calculated. In 46 patients (85.2%), bone involvement was observed. Thirty-nine (72.3%) had their spine affected, 35 (64.8%) pelvis and 33 (61.2%) femora. Fourteen patients had bone infarcts, 14 avascular necrosis, 2 vertebral fractures and 2 bone crises. Correlation analysis between S-MRI and BMB was (r(2)=.675; p=.0001). No evidence of correlation was observed between CT activity and S-MRI nor between CT activity and BMB. We have found a relationship between genotype and bone infiltration according to S-MRI site and complications. S-MRI is a simple method that provides useful information to evaluate bone infiltration and detect silent complications. Our results correlated with the BMB score but offer higher sensitivity, specificity and accuracy for classifying the extent of bone disease.     

Hematopoietic reconstitution after bone marrow transplantation: Assessment with MR imaging and H-1 localized spectroscopy

Magnetic resonance (MR) studies were performed in 14 patients as early as possible (21–110 days) after bone marrow transplantation (BMT). MR characteristics of lumbar vertebral bone marrow were studied with T1-weighted spin-echo imaging, water- and fatselective imaging with a frequency-selective excitation technique, and point-resolved spatially localized proton spectroscopy. Signals from water and fat protons and their T1 and T2 values were analyzed. Water proton signal intensity correlated well with cellularity within bone marrow, as determined with parallel iliac crest biopsies. The fraction of signal from water in red bone marrow of patients with allogeneic transplants from siblings (four cases) was significantly higher than in four patients with autologous transplants. The latter showed very low cellularity in the period of about 4 weeks after BMT because of the cytotoxic pretreatment of the bone marrow. The MR results in six patients with allogeneic transplants from unrelated donors ranged widely, depending on the complications after BMT. Analysis of data obtained with the different techniques showed that water- and fat-selective MR imaging and spectroscopic methods are useful for noninvasive monitoring of hematopoietic reconstitution after BMT.     

Intrathoracic complications following allogeneic bone marrow transplantation: CT findings

The authors retrospectively reviewed computed tomographic (CT) scans of 18 patients who developed 21 episodes of intrathoracic complications after allogeneic bone marrow transplantation (BMT). Pathologic and/or microbiologic diagnoses were available for all patients. All patients were immunocompromised due to either graft-versus-host disease (GVHD), neutropenia, or recurrent malignancy after BMT. CT demonstrated diagnostically relevant findings that were not apparent at radiography in 12 of the 21 cases (57%). These included a ground-glass pattern in early pneumonia (n = 5); a peripheral distribution in GVHD, bronchiolitis obliterans organizing pneumonia, and eosinophilic drug reaction (n = 4); cavitating lesions in Pneumocystis carinii pneumonia (n = 1); hemorrhagic infarcts in aspergillosis (n = 1); and mediastinal adenopathy in recurrent Hodgkin disease (n = 1). The authors conclude that chest CT is superior to radiography in demonstrating the presence, distribution, and extent of intrathoracic complications developing in patients after allogeneic BMT. CT is useful in guiding procedures for tissue diagnosis.     

Ribbing disease: radiographic and biochemical characterization,lack of response to pamidronate

Ribbing disease is a rare form of sclerosing dysplasia characterized by benign endosteal and periosteal bone growth confined to the diaphyses of the long bones, usually the tibiae and femora. The onset is usually after puberty and the most common presentation is pain that is usually self-limited, but may progress. The etiology and optimal treatment for the disease are unknown. We present the case of a 39-year-old Hispanic man with clinical and radiological manifestations of Ribbing disease. Radiographs and CT imaging demonstrated typical cortical thickening in the mid-diaphyses of the tibiae bilaterally that correlated with intense tracer uptake on (99m)Tc-MDP bone scans. MRI demonstrated cortical thickening and abnormal marrow signal consistent with marrow edema. Bone marrow edema may explain the pain frequently associated with the disease. Multiple serum and urine markers of bone metabolism were within normal limits. In an effort to ameliorate pain, the patient was treated with the bisphosphonate, pamidronate. In spite of treatment, pain increased, requiring additional and larger doses of analgesics. Serial radiographs, CT, bone scans, and MRI all demonstrated disease progression with pamidronate treatment. In this report we present for the first time the finding of bone marrow edema with MRI as well as disease progression during intravenous pamidronate treatment.     

Computed tomographic assessment of patients following radical surgery for malignant mesothelioma.

Serial computed tomographic (CT) scans of the thorax and upper abdomen were performed in eight patients following radical surgery (pleuro-pneumonectomy) for diffuse malignant mesothelioma of the pleura. The post-operative appearances included a well defined membrane lining the pleuro-pneumonectomy space in seven cases; in two cases this resembled the original tumour. In six patients there was upward abdominal visceral displacement on the side of the surgery due to diaphragmatic resection; this resulted in contralateral mediastinal shift in four patients. One patient required a diaphragmatic prosthesis which produced a distinctive CT appearance. CT suggested recurrent mesothelioma in five cases. Although two patients had evidence of intrathoracic recurrence, in three patients the only feature was the non-specific finding of abdominal ascites. The normal CT appearances after pleuro-pneumonectomy should be recognized to facilitate radiological interpretation. With careful application CT is of value for the assessment of recurrent disease in patients following radical surgery for malignant mesothelioma.     

Early recognition of recurrent hepatocellular carcinoma utilizing gallium-67 citrate scintigraphy

Gallium-67 scintigraphy is a valuable test together with other screening tests such as alpha feto-protein (AFP) and other imaging modalities in following up recurrent hepatocellular carcinoma (HCC). Three patients were followed in our institution for intervals varying from 2-24 mo after successful resection of uninodular localized hepatomas. In the first patient, gallium scan showed abnormal localized activity while the computed tomography (CT) scan and the magnetic resonance imaging were negative. Liver function tests and AFP were also normal and the patient was operated upon only on the basis of the gallium scan. The second patient had a follow-up gallium scan 2 mo after the first operation that showed an area of increased activity along the inferior aspect of the right lobe. A CT scan done after that showed no evidence of recurrence, but subsequently became positive when repeated 4 mo later. The third patient had abnormal simultaneous gallium scan and CT scan demonstrating a recurrence in the left adrenal gland while both AFP and carcinoembryonic antigen were normal. This has led us to consider every patient a candidate for a baseline and follow-up gallium scan for evaluation for recurrence following HCC.     

Imaging characteristics of toxoplasmosis encephalitis after bone marrow transplantation: report of two cases and review of the literature

Toxoplasmosis encephalitis is a severe, but often misdiagnosed complication in patients after bone marrow transplantation (BMT). We describe the unique computed tomography (CT) and magnetic resonance (MR) imaging features of cerebral toxoplasmosis in two bone marrow recipients and compare them to the cases in the literature. To our knowledge, this is the first report analyzing the appearance of cerebral toxoplasmosis on diffusion-weighted MR imaging (DWI).     

Early diagnosis of spinal metastases by CT and MR studies

Fifteen patients with known metastatic or high-risk primary cancer, normal neurologic examinations, and new abnormalities on 99mTc bone scan were evaluated with spinal CT and magnetic resonance (MR) imaging. Four patients underwent CT metrizamide myelography. Spinal CT and MR agreed in 14 of 15 patients demonstrating spinal metastases in 12 patients and benign disease in two. In one patient spinal CT was normal, but MR showed altered marrow signal consistent with metastatic disease. Epidural tumor was demonstrated by CT metrizamide myelography in four cases, all correctly identified by MR. Further evaluation of spinal MR in this setting is warranted.     

MRI of intracranial toxoplasmosis after bone marrow transplantation

Toxoplasma encephalitis was confirmed by biopsy in three patients with bone marrow (BMT) or peripheral blood stem-cell transplantation (PBSCT). All had MRI before antimicrobial therapy. The intensity of contrast enhancement was very variable. One patient had one large, moderately enhancing cerebral lesion and several smaller almost nonenhancing lesions. The second had small nodular and haemorrhagic lesions without any enhancement. The third had late cerebral toxoplasmosis and showed multiple lesions with marked contrast enhancement. The moderate or absent contrast enhancement in the two patients in the early phase of cerebral toxoplasmosis may be related to a poor immunological response, with a low white blood cell count in at least one patient. Both received higher doses of prednisone than the patient with late infection, leading to a reduced inflammatory response. In patients with a low leukocyte count and/or high doses of immunosuppressive therapy, typical contrast enhancement may be absent. Received: 24 February 1999/Accepted: 14 June 1999     

MR imaging in toxoplasmosis encephalitis after bone marrow transplantation: paucity of enhancement despite fulminant disease

We present a patient who underwent bone marrow transplantation (BMT) after developing chronic myelocytic leukemia. Four months after BMT, he became comatose and died. MR imaging revealed multifocal brain lesions that were progressive but produced no edema. Postcontrast studies revealed that most of the lesions were nonenhancing. There was only discrete, irregular leptomeningeal enhancement with possible minimal enhancement of the cortex and subcortical white matter. Autopsy showed overwhelming toxoplasmosis encephalitis. This case illustrates that toxoplasmosis lesions may lack obvious contrast enhancement in the brain of the immunocompromised patients, despite severe involvement. Recognition of this unusual MR imaging manifestation of toxoplasmosis should lead to earlier diagnosis and treatment.     

Venocclusive disease of the liver: prospective study of US evaluation.

Twenty-one bone marrow transplantation (BMT) patients were studied prospectively to determine the prevalence of sonographic hepatobiliary abnormalities and to determine if these abnormalities were associated with hepatic venocclusive disease (VOD). Baseline US was performed in all patients prior to chemoradiation therapy, with follow-up ultrasound (US) examinations at the time of BMT and 14 days and 28 days after BMT. Sonograms were reviewed for the presence of ascites, gallbladder wall thickening, hepatosplenomegaly, hepatofugal flow, hepatic vein compression, increased periportal echogenicity, and increased hepatic echotexture. The baseline scans showed 13 of 21 patients (62%) with abnormalities prior to BMT. Within 2 weeks after BMT, serial US showed interval development of hepatomegaly in five patients (three with VOD and two without), gallbladder wall thickening in one (with VOD), hepatic vein compression in two (both with VOD), hepatofugal flow in one (without VOD), and ascites in one (with VOD). US scans obtained 4 weeks after BMT in 15 of the 21 patients showed even fewer new abnormalities. No sonographic finding was strongly associated with VOD.     

Mastocytosis: magnetic resonance imaging patterns of marrow disease

Objective. To report the bone marrow MRI findings of patients with mastocytosis and correlate them with clinical, pathologic, and radiographic features. Design and patients. Eighteen patients with mastocytosis had T1-weighted spin echo and short tau inversion recovery MRI of the pelvis at 0.5 T. In each patient the MR pattern of marrow disease was classified according to intensity and uniformity and was correlated with the clinical category of mastocytosis, bone marrow biopsy results, and radiographic findings. Results. Two patients had normal MRI scans and normal bone marrow biopsies. One patient had a normal MRI scan and a marrow biopsy consistent with mastocytosis. Fifteen patients had abnormal MRI scans and abnormal marrow biopsies. There were several different MR patterns of marrow involvement; none was specifically associated with any given clinical category of mastocytosis. Fifteen of the 18 patients had radiographs of the pelvis; of those, 13 with abnormal MRI scans and abnormal marrow biopsies had the following radiographic findings: normal (nine); sclerosis (three); diffuse osteopenia (one). Conclusion. While radiographs are very insensitive for the detection of marrow abnormalities in mastocytosis, MRI is very sensitive and may display several different patterns of marrow involvement.