S Salemi

MR cholangiography in orthotopic liver transplantation: sensitivity and specificity in detecting biliary complications

Boraschi P, Donati F, Gigoni R, Volpi A, Salemi S, Filipponi F, Falaschi F. MR cholangiography in orthotopic liver transplantation: sensitivity and specificity in detecting biliary complications.
Clin Transplant 2010: 24: E82–E87.
© 2009 John Wiley & Sons A/S.

Secretin-stimulated MR cholangio-pancreatography in the evaluation of asymptomatic patients with non-specific pancreatic hyperenzymemia

PURPOSE To assess the diagnostic value of secretin-stimulated MRCP (SS-MRCP) compared with conventional MRCP in asymptomatic patients with mild elevations of pancreatic enzymes. MATERIALS AND METHODS Eighty asymptomatic patients with pancreatic hyperenzymemia underwent MR imaging at 1.5T-device (Signa EXCITE, GE Healthcare). After the acquisition of axial T1w,T2w sequences, and conventional MRCP, SS-MRCP was performed using a single-slice coronal breath-hold, thick-slab, SSFSE T2w sequence, repeated every 30s up to 15 min following intravenous injection of secretin (Secrelux, Sanochemia). RESULTS On the basis of the standards of reference, our final diagnoses were: negative findings (n=23), pancreas divisum (n=22), mild chronic pancreatitis (n=14), inflammatory ampullary stenosis (n=3), juxtapapillary duodenal diverticulum (n=1), small cystic lesions (<1cm) (n=22; 5/22 cases associated with pancreas divisum). The image quality of SS-MRCP was significantly higher than that of conventional MRCP (p<0.0001). Standards of reference did not differ significantly from of SS-MRCP findings (p=0.5), while was statistically different from those of conventional MRCP (p<0.0001). A significant difference was found between conventional MRCP and SS-MRCP findings (p<0.0001). CONCLUSION In asymptomatic patients with non-specific pancreatic hyperenzymemia SS-MRCP may represent the best non-invasive diagnostic technique, since it gives morphological and functional information.

Focal nodular hyperplasia of the liver: diffusion and perfusion MRI characteristics

PURPOSE To present diffusion and perfusion magnetic resonance imaging (MRI) characteristics of focal nodular hyperplasia (FNH) of the liver. MATERIALS AND METHODS Thirty-five patients with 52 FNHs (21 were pathologically-confirmed) underwent MRI at 1.5-T device. MR diffusion [diffusion-weighted imaging (DWI)] was performed using a free-breathing single-shot, spin-echo, echo-planar sequence with b gradient factor value of 500 s/mm². MR perfusion [perfusion-weighted imaging (PWI)] consisted of a 3D free-breathing LAVA sequence repeated up to 5 minutes after injection of 7 mL Gd-BOPTA (MultiHance, Bracco, Italy) and 20 mL saline flush at a flow rate of 4 mL/s. Apparent diffusion coefficient (ADC) and time-signal intensity curve (TSIC) were obtained for both normal liver and each FNH by two reviewers in conference; maximum enhancement (ME) percentage, time to peak enhancement (TTP), and maximal slope (MS) were also calculated. RESULTS On DWI mean ADC value was 1.624×10(-3) mm(2)/s for normal liver and 1.629×10(-3) mm(2)/s for FNH. ADC value for each FNH and the normal liver was not statistically different (P=.936). On PWI, TSIC-Type 1 (quick and marked enhancement and quick decay followed by slowly decaying) was observed in all 52 FNHs, and TSIC-Type 2 (fast enhancement followed by slowly decaying plateau) in all normal livers. The mean ME, TTP and MS values were significantly different for FNH and normal liver (P=.005). CONCLUSION FNHs of the liver showed typical diffusion and perfusion MRI characteristics in all cases. On the ADC map, we could get similar value between the FNHs and the background parenchyma. On the perfusion imaging, FNHs showed a different pattern distinguished from the background liver.

MRA in Liver and in Orthotopic Liver Transplants

MR imaging provides the necessary information about variations in the vascular and biliary anatomy and allows evaluation of the hepatic parenchyma for diffuse or focal abnormalities.

Secretin-stimulated multi-detector CT versus mangafodipir trisodium-enhanced MR imaging plus MRCP in characterization of non-metastatic solid pancreatic lesions

BACKGROUND AND AIM Our study was aimed to compare multiphasic multi-detector computed tomography after secretin stimulation and mangafodipir trisodium-enhanced magnetic resonance imaging plus MR cholangiopancreatography in the characterization of solid pancreatic lesions. PATIENTS AND METHODS Forty patients with ultrasound diagnosis of solid pancreatic lesion prospectively underwent both multi-detector computed tomography and magnetic resonance imaging. Three minutes after intravenous administration of secretin, post-contrast computed tomography scans were performed 40, 80, and 180 s after contrast medium injection. MR protocol included axial/coronal, thin/thick-slab, single-shot T2 w sequences and axial/coronal T1 w breath-hold spoiled gradient-echo images before and 30-40 min after intravenous infusion of manganese dipyri-doxal diphosphate. Different observers blindly evaluated the ability of computed tomography and magnetic resonance imaging to characterize focal pancreatic lesions. Surgery, biopsy, and/or follow-up were considered as our diagnostic gold standard. RESULTS Thirty-five focal pancreatic lesions (adenocarcinoma, n=18; focal chronic pancreatitis, n=4; endocrine tumor, n=6; metastasis, n=1; cystic tumor, n=3; indeterminate cystic lesions, n=3) were present in 34 patients since the remaining 6 subjects showed no pathological finding. Both multi-detector computed tomography and magnetic resonance imaging showed a statistically significant correlation with the gold standard and between themselves in the characterization of 29 solid lesions of the pancreas (p<0.05). CONCLUSION Both imaging techniques well correlate to final diagnosis of non-metastatic solid pancreatic lesions and particularly of adenocarcinomas with a slight advantage for mangafodipir trisodium-enhanced magnetic resonance imaging plus MR cholangiopancreatography.