Computed tomography (CT), especially contrast-enhanced CT (CECT), provides important information on the severity and prognosis of acute pancreatitis (AP). Magnetic resonance imaging (MRI) has become a useful tool as an alternative to CT in the assessment of AP. The primary aim of our study was to determine the diagnostic value of nonenhanced MRI (NEMRI) to assess severity and predict outcome in patients with AP from the third to fifth day after admission. We also correlated MRI findings with CT and biochemical parameters. The study included 101 patients (49 men, 52 women, median age 62 yr, range 20-82) with a diagnosis of AP admitted to our hospital between January 1, 2004 and June 31, 2005. The inclusion criteria consisted of a combination of clinical features, a typical case history, elevation of serum pancreatic enzymes, and diagnosis confirmed by imaging studies. Contrast-enhanced spiral CT exams were performed in all patients from the third to fifth day after admission, and Balthazar grade and CT severity index were calculated. All patients underwent NEMRI, and MR severity index (MRSI) was calculated. We also performed magnetic resonance cholangiopancreatography (MRCP) in all patients to detect bile duct lithiasis. Significant correlation between CECT and NEMRI was found for Balthazar grade (P<0.001) and the assessment of pancreatic necrosis (P<0.001), as well as between the combined severity indices (rho=0.819, P<0.001). MRSI correlated with Ranson score (rho=0.656, P<0.01), C-reactive protein (CRP) levels 48 h after admission (rho=0.502, P<0.01), appearance of systemic complications (rho=0.576, P<0.01), and length of hospital stay (rho=0.484, P<0.01). Considering the Atlanta criteria as the gold standard and the Ranson score, no difference in sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the two methods was observed. Comparing the group of patients with presumed acute pancreatic hemorrhage with the group of patients with severe AP, we found a significantly higher APACHE II score on the first day (P<0.05), that the development of systemic complications was more frequent (P < 0.05), and that the hospital stay and ICU management of patients with MRI signs of pancreatic hemorrhage tended to be longer. NEMRI is comparable to CECT in the early assessment of the severity of AP, and both methods are equally efficient in predicting local and systemic complications of AP. MRI has a potential advantage over CT in detecting bile duct lithiasis and pancreatic hemorrhage.

Background Studies showed gender-associated differences in multiple sclerosis (MS) disease evolution and in the evolution of conventional magnetic resonance imaging (MRI) findings. Objective The aim of this study was to investigate gender differences according to a number of conventional and nonconventional MRI measures in patients with MS. Methods We examined 763 consecutive patients with MS [499 (19.2% men) relapsing-remitting (RR), 230 (24.8% men) secondary-progressive, and 34 (44.1% men) primary-progressive], 32 (21.9% men) patients with clinically isolated syndrome (CIS), and 101 (30.7% men) normal controls (NC). Patients were assessed using conventional and nonconventional MRI measures. Gender-related MRI differences were investigated using general linear model analysis, corrected for MS disease type. Results In the total MS group, male patients showed lower normalized peripheral gray matter (GM) (P < 0.001) and normalized GM (P = 0.011) volumes than female patients. Female patients presented lower normalized white matter (WM) volumes (P = 0.011). These gender effects were not observed in NC. Male patients also showed more advanced central atrophy (P = 0.022). In RRMS male patients, there was also a higher lateral ventricle volume (P = 0.001). The GM-WM normalized ratio was lower for male patients with MS compared with male NC (0.97 vs. 1.09, P < 0.001) but not in patients with CIS compared with NC. Conclusions There were no significant gender-related differences regarding nonconventional MRI measures. GM and central atrophy are more advanced in male patients, whereas WM atrophy is more advanced in female patients. These gender-related MRI differences may be explained by the effect of sex hormones on brain damage and repair mechanisms.