Role of 99mTc methylene diphosphonate bone imaging in the management of lymphoma

The role of modern techniques of 99mTc methylene diphosphonate bone imaging in the management of lymphoma patients was assessed by comparing results of 107 bone scans in 16 patients with Hodgkin's disease, and 45 patients with non-Hodgkin's lymphoma to simultaneous radiologic, clinical, and histopathologic features as well as to subsequent disease course. The sensitivity and specificity were both greater than or equal to 0.96 in both Hodgkin's disease and non-Hodgkin's lymphoma and the overall accuracy by site was 98%. The scan proved to be useful in the definition and follow-up of skeletal lymphomatous disease in both symptomatic and asymptomatic patients, and defined abnormalities which were not predicted by either serum alkaline phosphatase activity or the presence of bone marrow involvement. In no patient, however, did the bone scan result by itself alter either initial staging or estimates of extent of disease at the time of relapse. Bone scanning, therefore, cannot be recommended as a screening procedure in patients with lymphoma; rather, this test is best reserved for the definition and follow-up of skeletal metastases in patients with active, concomitant, extraosseous disease.     

Value of Tc-99m sestamibi scintigraphy in the detection of bone lesions in multiple myeloma: comparison with Tc-99m methylene diphosphonate

Technetium 99m-2-methoxyisobutylisonitrile (Tc-99m MIBI) is a lipophilic agent that accumulates preferentially within living malignant cells due to the higher transmembrane electrical potential as a consequence of the higher metabolic rate than in the surrounding normal cells. It has been effectively used to detect malignant tumors at diagnosis and follow-up and has been reported to be useful in detecting disease lesions in multiple myeloma. We studied 28 consecutive patients with multiple myeloma at diagnosis to determine the value of Tc-99m MIBI in comparison with Tc-99m methylene diphosphonate (MDP), conventional X-rays, computed tomography (CT) scan, and magnetic resonance imaging (MRI). We found 26 patients with obvious osteolytic lesions in X-rays, 22 patients with positive Tc-99m MIBI scans, and 15 patients with positive Tc-99m MDP scans. There was no coincidence of the positive lesions in the two scans, while in two patients the osteolytic areas were positive in the Tc-99m MDP scans, and in one case the osteolytic area was positive in the Tc-99m MIBI scan. The intensity of Tc-99m MIBI scans correlated with disease activity as determined by lactate dehydrogenase (LDH) (p<0.05), C-reactive protein (CRP) (p<0.01), beta2-microglobulin (p<0.05), and serum ferritin (p<0.01). We believe that Tc-99m MIBI scintigraphy can detect bone marrow lesions in myeloma patients that cannot be detected by other imaging methods and that it can be useful especially in solitary myeloma to exclude other involved sites. In addition, it could be a prognostic factor related to disease activity and multidrug resistance. We believe that a multicenter study is needed to evaluate the usefulness of this agent.     

Knee magnetic resonance imaging in childhood chronic monarthritis.

OBJECTIVE: To describe the usefulness of magnetic resonance imaging (MRI) of the knee in the evaluation of chronic monarthritis of uncertain cause in childhood. METHODS: We retrospectively reviewed 21 children referred to our clinic with a putative diagnosis of chronic inflammatory monarthritis of the knee who had MRI performed between May 1993 and June 1997. The median age was 13 years (range 2-17) and 11 were girls. RESULTS: The clinical diagnosis prior to MRI assessment was inflammatory arthritis in 16 patients, and a primary noninflammatory cause in 5. MRI was done in the patients with presumptive inflammatory arthritis when there were atypical symptoms, signs, or radiographs (n = 14), or when they failed to respond to therapy (n = 2). In the patients with a presumptive noninflammatory diagnosis, MRI was performed to clarify the diagnosis. Twelve children (57%) had MRI evidence of a noninflammatory diagnosis. In 4 children (19%) the MRI study indicated the presence of arthritis, and in 5 children (24%) the MRI studies were normal. The noninflammatory diagnoses included: lipoma arborescens (n = 1), vascular malformation [intraarticular (n = 1), extraarticular (n = 1)], synovial chondromatosis (n = 2), partial anterior cruciate ligament tear (n = 2), traumatic bone contusion (n = 2), possible meniscal tear (n = 1), osteochondritis dissecans (n = 1), and a soft tissue mass of uncertain significance in the suprapatellar pouch (n = 1). CONCLUSION: Inflammatory arthritis is usually diagnosed by clinical assessment alone. Uncommonly, when a single joint is involved, and atypical features are identified by a pediatric rheumatologist, other causes of chronic pain and swelling need to be excluded. In this selected patient population, MRI is a useful tool either to confirm the presence of inflammatory arthritis or to investigate a wide range of pathology that can mimic knee joint arthritis.     

Bone scintigraphy in chronic knee pain: comparison with magnetic resonance imaging

OBJECTIVE: To compare increased bone uptake of 99Tcm-MDP and magnetic resonance (MR) detected subchondral lesions, osteophytes, and cartilage defects in the knee in middle aged people with long-standing knee pain. METHODS: Fifty eight people (aged 41-58 years, mean 50) with chronic knee pain, with or without radiographic knee osteoarthritis, were examined with bone scintigraphy. The pattern and the grade of increased bone uptake was assessed. On the same day, a MR examination on a 1.0 T imager was performed. The presence and the grade of subchondral lesions, osteophytes, and cartilage defects were registered. RESULTS: The kappa values describing the correlation between increased bone uptake and MR detected subchondral lesions varied between 0.79 and 0.49, and between increased bone uptake and MR detected osteophytes or cartilage defects the values were < 0.54. The kappa values describing the correlation between the grade of bone uptake and the grade of the different MR findings was < 0.57. CONCLUSIONS: Good agreement was found between increased bone uptake and MR detected subchondral lesion. The agreement between increased bone uptake and osteophytes or cartilage defects was in general poor as well as the agreement between the grade of bone uptake and the grade of the MR findings.     

Acute myelofibrosis: multifocal bone marrow infiltration detected by scintigraphy and magnetic resonance imaging

 Acute myelofibrosis is a rare, malignant hematological disorder of unknown etiology with an inevitably fatal outcome. Here we present the study of a 63-year-old Caucasian man with acute onset of pancytopenia. Repeated bone marrow biopsies showed dense fibrosis and hypoplastic hematopoiesis raising various differential diagnoses of malignant and nonmalignant conditions. Bone marrow scintigraphy and magnetic resonance imaging (MRI) showed areas suggesting neoplastic infiltration, mainly in both femurs and tibias. Histological examination of a surgical biopsy of the left tibia revealed acute megakaryoblastic leukemia. As the patient refused polychemotherapy, therapy with interferon gamma was initiated but discontinued prematurely because of intolerable side effects. The presented case therefore suggests that the combination of bone marrow scintigraphy and MRI is a valuable diagnostic tool in patients presenting with myelofibrosis of unknown origin. Received: 22 March 1999 / Accepted: 28 September 1999     

Diffusion-weighted magnetic resonance imaging for the assessment of fibrosis in chronic hepatitis C

Liver biopsy is the gold standard for assessing fibrosis but has several limitations. We evaluated a noninvasive method, so-called diffusion-weighted magnetic resonance imaging (DWMRI), which measures the apparent diffusion coefficient (ADC) of water, for the diagnosis of liver fibrosis in patients with chronic hepatitis C virus (HCV). We analyzed 20 healthy volunteers and 54 patients with chronic HCV (METAVIR: F0, n = 1; F1, n = 30; F2, n = 8; F3, n = 5; and F4, n = 10) prospectively included. Patients with moderate-to-severe fibrosis (F2-F3-F4) had hepatic ADC values lower than those without or with mild fibrosis (F0-F1; mean: 1.10 +/- 0.11 versus 1.30 +/- 0.12 x 10(-3) mm2/s) and healthy volunteers (mean: 1.44 +/- 0.02 x 10(-3) mm2/s). In discriminating patients staged F3-F4, the areas under the receiving operating characteristic curves (AUCs) were 0.92 (+/-0.04) for magnetic resonance imaging (MRI), 0.92 (+/-0.05) for elastography, 0.79 (+/-0.08) for FibroTest, 0.87 (+/-0.06) for the aspartate aminotransferase to platelets ratio index (APRI), 0.86 (+/-0.06) for the Forns index, and 0.87 (+/-0.06) for hyaluronate. In these patients, the sensitivity, specificity, positive predictive value, and negative predictive value were 87%, 87%, 72%, and 94%, respectively, with an ADC cutoff level of 1.21 x 10(-3) mm2/s. In discriminating patients staged F2-F3-F4, the AUC values were 0.79 (+/-0.07) for MRI, 0.87 (+/-0.05) for elastography, 0.68 (+/-0.09) for FibroTest, 0.81 (+/-0.06) for APRI, 0.72 (+/-0.08) for the Forns index, and 0.77 (+/-0.06) for hyaluronate. CONCLUSION: This preliminary study suggests that DWMRI compares favorably with other noninvasive tests for the presence of significant liver fibrosis.     

Comparison of echocardiography with magnetic resonance imaging in the assessment of the athlete's heart

AIM: The purpose of the study was to compare the accuracy of M-modeechocardiography and two different two-dimensional echocardiographicapproaches in the assessment of left ventricular mass and volumesin endurance-trained and strength-trained athletes, using magneticresonance imaging as reference standard. METHODS AND RESULTS: We studied 19 athletes and 10 untrained control subjects, M-modeand two-dimensional echocardiography were compared to magneticresonance imaging. M-mode echocardiographic left ventricularmass was calculated using the Penn cube convention. Two-dimensionalechocardiographic left ventricular mass was calculated using(1) the area—length method as proposed by the AmericanSociety of Echocardiography (ASE) and (2) as proposed by Reichek.The best correlation between magnetic resonance imaging andechocardiographic left ventricular mass and volumes was observedwith the ASE two-dimensional echocardiographic method. The agreementbetween them (–3·4±7·6 g and 18·5±19·5ml) was better than between Reichek two-dimensional echocardiographyand magnetic resonance imaging (–39·4±15·4-gand 52·8±21·7 ml), and demonstrated lessrandom difference than M-mode echocardiography and magneticresonance imaging (3·2±21·1 g resp. 15·1±30·0ml). CONCLUSION: We conclude that the ASE two-dimensional echocardiographic approach,when using magnetic resonance imaging as a reference standard,was the most accurate estimator of left ventricular mass andvolumes in both controls and athletes.     

Increased bone metabolism in rheumatoid arthritis as measured by the whole-body retention of 99Tcm methylene diphosphonate.

Bone metabolism in 21 patients with rheumatoid disease was investigated by measurement of the 24-hour whole body retention (WBR) of 99Tcm methylene diphosphonate (MDP) in parallel with clinical, radiological, and biochemical measurements (urinary excretion of hydroxyproline) of disease activity. Corticosteroid-treated patients of those with other forms of metabolic bone disease were excluded from the study. WBR was increased in the rheumatoid patients as compared with 21 age- and sex-matched controls (p less than 0.05), and there was a significant correlation in the rheumatoid group between WBR and urinary excretion of hydroxyproline (p less than 0.01) and between urinary excretion of hydroxyproline and an articular index (p less than 0.05) and global index (p less than 0.01) of disease activity. The increased WBR of the rheumatoid patients was not explicable by factors such as immobilisation, and the results are interpreted as reflecting an overall increase in bone metabolism which may occur in rheumatoid arthritis as part of the disease process.     

Bone scintigraphy and magnetic resonance imaging in adult-onset Still's disease.

Adult-onset Still's disease (AOSD) is an acute systemic inflammatory disorder of unknown origin. We report a patient whose AOSD presented with the commonly accepted diagnostic clinical signs and laboratory parameters. The painful joints distinctly demonstrated increased uptake of 99mTc-methylene diphosphonate in scintigraphy and areas of increased gadolinium-enhanced signal in MRI. Biopsies indicated bone marrow edema. AOSD in association with bone marrow edema had not been previously demonstrated. AOSD is often diagnosed after a considerable delay, bone scintigraphy, and magnetic resonance imaging may offer new imaging techniques for early diagnosis and successful therapy in follow-up examinations.     

Inflammatory bowel disease evaluated by low-field magnetic resonance imaging. Comparison with endoscopy, 99mTc-HMPAO leucocyte scintigraphy, conventional radiography and surgery

BACKGROUND: To evaluate the use of low-field magnetic resonance imaging (MRI) in active inflammatory bowel disease (IBD). METHODS: MRI was executed in a consecutive cohort of 28 patients with Crohn disease (CD) and in 17 with ulcerative colitis (UC) prior to glucocorticoid treatment (1 mg prednisolone orally/kg body weight/day). MRI was repeated after 2-3 weeks (22 CD, 12 UC), and again after treatment completion or prior to surgery (18 CD, 6 UC). Five bowel segments were evaluated separately. MRIs were blindly evaluated by two observers, and findings compared with 39 leucocyte scintigraphies, 38 endoscopies, 15 double-contrast barium enemas, 66 small-bowel radiographic examinations and surgery in 23 patients. RESULTS: In CD, blinded evaluation revealed a kappa (kappa) of 0.84 (95% confidence interval (CI) 0.78-0.91). In UC, kappa was 0.66 (95% CI 0.55-0.78). Agreements regarding disease extension between MRI and other modalities in CD were found in 345 bowel segments out of 391 (88.2%) at risk, and in UC in 209/235 (88.9%). Colonic disease activity gradings by radiography and endoscopy correlated significantly with T2-signal intensity (SI(T2)) and increments in T1-signal intensity (%SI(T1)) in both diseases. Significant correlations between MRI indices of disease activity and CDAI in CD (MRI-SI(T2): P <0.0001: MRI% SI(T1): P=0.0008) and the Powell-Tuck index in UC (MRI% SI(T1): P=0.008) were found. CONCLUSIONS: With low interobserver variation and high concordance of findings with other examinations. low-field MRI seems a valuable modality in active IBD. In addition, MRI expressions of disease activity correlate to clinical, radiographic and endoscopic disease activity.     

Diagnosis of idiopathic myositis: value of 99mtechnetium pyrophosphate muscle scintigraphy and magnetic resonance imaging in targeted muscle biopsy

Our objective was to study the value of ^99mtechnetium-pyrophosphate (^99mTc-PYP) muscle scintigraphy and magnetic resonance imaging (MRI) in detecting areas of likely muscle inflammation and in increasing the rate of positive muscle biopsies in patients with suspected myositis. The results showed that in 13 out of 13 patients with clinical and/or signs of inflammatory muscle disease, increased ^99mTc-PYP uptake was demonstrated at different muscle sites 3 h after isotope injection. Subsequent MRI of symmetric muscle areas with enhanced ^99mTc-PYP uptake revealed signal patterns suggesting inflammation in all cases. Biopsy of these targeted muscles demonstrated characteristic histopathologic signs of muscle inflammation in 9 out of 13 patients. Four of these 9 patients had clinically atypical disease or did not show elevated creatine phosphokinase levels. Seven of these 9 patients had not been pretreated with corticosteroids. In 4 patients only muscle fiber atrophy and/or necrosis without cellular infiltrations was seen. These 4 patients had received either high doses of corticosteroids or low doses over longer periods of time before muscle biopsy. In conclusion, the combination of ^99mTc-PYP muscle scintigraphy and MRI demonstrated muscle areas with maximum inflammatory signal patterns. Targeting of muscles by MRI only will probably yield reliable results of muscle biopsy in cases of clinically and serologically characteristic myositis. ^99mTc-PYP muscle scintigraphy may provide useful initial information about localization of inflamed muscle tissue, especially in atypical disease. Treatment with corticosteroids prior to histologic diagnosis may abolish inflammatory infiltrations in affected muscle tissue. Received: 24 August 1997 / Accepted 9 January 1998     

Comparison of magnetic resonance real-time imaging of left ventricular function with conventional magnetic resonance imaging and echocardiography

This study analyzes the accuracy of a new real-time magnetic resonance imaging (MRI) technique (acquisition duration, 62 ms/image) and echocardiography for the determination of left ventricular (LV) end-diastolic volume, end-systolic volume, ejection fraction, and muscle mass when compared with turbo gradient echo imaging as the reference standard. Thirty-four patients were examined with digital echocardiography, standard, and real-time MRI. A close correlation was found between the results of real-time imaging and the reference standard for end-diastolic volume, end-systolic volume, and ejection fraction (r >0.95), with a lower correlation for LV muscle mass (r = 0.81). Correlations between echocardiography and the reference standard were lower for all parameters. Real-time MRI enables the acquisition of high-quality cine loops of the entire heart in minimal time without electrocardiographic triggering or breath holding. Thus, patient setup and scan time can be reduced considerably. Results are similar to the reference standard and superior to echocardiography for determining LV volumes and ejection fraction. This technique is a valid alternative to current approaches and can form the basis of every cardiac MRI examination.     

Myocardial perfusion imaging: clinical experience and recent progress in radionuclide scintigraphy and magnetic resonance imaging

In the past 20 years, radionuclide scintigraphy has proven to be a sensitive clinical tool in the assessment of myocardial perfusion abnormalities. Magnetic resonance imaging may also be used to study myocardial perfusion, but its potential value still has to emerge in the clinical setting. This review addresses the potential and achievements of both methods in clinical cardiology.     

Contrast-enhanced magnetic resonance imaging assessment of scar size in patients with chronic myocardial infarction.

BACKGROUND: In the assessment of myocardial infarction (MI) mass, contrast-enhanced magnetic resonance imaging (CE-MRI) is comparable to single-photon emission computed tomography (SPECT). The aim of the present study was to determine whether the MI area, as assessed at CE-MRI and SPECT, is comparable to mass evaluation. We also compared CE-MRI and SPECT estimates of the MI area with functional evaluations made at echocardiography and kinetic MRI (cine-MRI). METHODS: We used a 1.0 Tesla MRI scanner and an inversion-recovery turboFLASH sequence, a tomographic gamma-camera and second-harmonic ultrasound systems. Two blinded operators assessed the extent of scarring, expressed as a percentage of the whole left ventricle (LV), using a 16-segment model. We studied 55 consecutive patients with a clinically stable healed MI (50 Q wave, 5 non-Q wave). RESULTS: The scar mass was 19+/-23% of the LV at CE-MRI and 21+/-25% at SPECT; the scar area was 29+/-23% of the LV at CE-MRI, 41+/-28% at SPECT, 29+/-31% at cine-MRI, and 32+/-29% at echocardiography. The Bland-Altman bias between CE-MRI and SPECT mass estimations was -2% of the LV with a+/-23% limit of agreement (LOA), while the bias between the area assessments was -12% with a+/-42% LOA. Bias between CE-MRI and functional evaluation by cine-MRI and echocardiography was 0% with a+/-39% LOA and -3% with a+/-36% LOA respectively. Comparing SPECT with cine-MRI and echocardiography the bias was 12% with a+/-52% LOA and 9% with a+/-56% LOA respectively. CONCLUSIONS: CE-MRI has proved to be comparable to SPECT in the assessment of the healed MI mass. Conversely, a high systematic error (high bias and LOA) renders CE-MRI and SPECT assessments of the MI area incomparable. Similarly (high bias and/or LOA) CE-MRI and SPECT estimations of the MI area cannot be compared with functional evaluation by echocardiography or cine-MRI.