Meniscal tears of the knee: accuracy of MR imaging

Before surgery, 277 menisci in 144 knees were examined with magnetic resonance (MR) imaging. They were then examined directly with arthroscopy or arthrotomy. Menisci were graded on a scale of 1-3 according to the character of the intrameniscal MR imaging signal. At surgery, 137 of 154 (89%) menisci exhibiting only grade 1 or grade 2 signal were found to be normal. One hundred sixteen of 123 (94%) menisci exhibiting intrameniscal signal communicating with a meniscal articular surface (grade 3 signal) had tears. If only a grade 3 signal is considered consistent with meniscal tears, then MR findings and surgical findings agreed in 91.3% of menisci. MR imaging can separate surgically significant from nonsignificant meniscal lesions and is useful in the noninvasive preoperative screening of suspected meniscal tears.     

Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy

To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice.     

Damage did not independently influence mortality in childhood systemic lupus erythematosus

Objective: To analyze clinical, laboratory and treatment features associated with death in a childhood-onset SLE population. Patients and methods: Patients with childhood-onset SLE followed at the State University of Campinas, Brazil, between 1980 and 2002 were included. Data on clinical and laboratory features of the disease were collected regularly. Logistic regression was used for analyzing association between clinical and laboratory features and death. Kaplan–Meyer tests were used to estimate the survival curves. Results: Of 61 patients identified, six were lost to follow-up during the first year of disease. The mean follow-up period of the remaining 55 patients was 3.25 years (SD=1.2). Mean SLICC/ACR-DI score was 4.9 (SD=3.4). Death occurred in 12 (21.8%) of 55 patients. Direct causes of death were: infection in six (50%), stroke in four (33.3%), and renal insufficiency in two (16.7%). Five patients (41.7%) died during the first 5 years of disease due to infection. Male gender (p=0.004; OR=9.1; 95% CI=7.6–21.0), infection (p=0.001; OR=4.2; 95% CI=1.6–15.2) and nephritis (p=0.02; OR=2.3; 95% CI=1.3–5.2) were independent factors associated with death in the multivariate analysis. The global survival rate adjusted for duration of disease was 93.9% in the first year of disease, 88.9% in the second year, 80.8% in the fifth year and 48.1% in 20 years of follow-up. When comparing survival curves, male gender, the presence of infection during the course of the disease and the presence of nephritis during follow-up had a worse survival. Conclusion: Male gender, the presence of infection and nephritis were independent risk factors for death in our Brazilian cohort. Damage did not independently influence survival in this study.     

Magnetic resonance imaging: absence of in vitro cytogenetic damage

Human lymphocytes and Chinese hamster ovary (CHO) cells in culture were exposed for 12 1/2 hours to a magnetic resonance imaging apparatus with a 2.35-Tesla magnet and 100-MHz radio frequency emission. The cells were examined for cytogenetic damage manifested either as chromosome aberrations or sister chromatid exchanges (SCEs), which constitute very sensitive measures of genetic and cellular damage. In either unstimulated or stimulated human lymphocytes, as well as in exponentially growing CHO cells, no increase in either chromosome aberrations or SCEs was found as a result of exposure to these MR conditions. The data indicate that long-term exposure to MR imaging conditions far exceeding those to be found in the clinical situation does not cause cytogenetic damage.