Geometric distortion evaluation using a multi-orientated water-phantom at 0.2 T MRI.

Magnetic Resonance Imaging (MRI) has been one of the most revolutionary medical imaging modalities in the past three decades. It has been recognized as a potential technique in the clinical diagnosis of diseases as well as tumor differentiation. Although MRI has now become the preferred choice in many clinical examinations, there are some drawbacks, which still limit its applications. One of the crucial issues of MRI is the geometric distortion caused by magnetic field inhomogeneity and susceptibility effects. The farther the lesion from the center of a magnetic field (off-center field), the more severe the distortion becomes, especially in low-field MRI. Hence, it might hinder the diagnosis and characterization of lesions in the presence of field inhomogeneity. In this study, an innovative multi-orientated water-phantom was used to evaluate the geometric distortion. The correlations between the level of image distortion and the relative off-center positions, as well as the variation of signal intensities, were both investigated. The image distortion ratios of axial, coronal and sagittal images were calculated.

Restenotic hepaticojejunostomy secondary to laparoscopic cholecistectomy bile duct injury treated with self- modified Gianturco-Rosh stents.

BACKGROUND/AIMS: Laparoscopic cholecystectomy is considered as a standard procedure for symptomatic gallstones. However, the incidence of iatrogenic bile duct injury is higher that the conventional cholecystectomy. In the present study was analyzed the results in 6 patients with iatrogenic bile duct injury during laparoscopic cholecystectomy with restenotic hepaticojejunostomy treated with self-modified Gianturco-Rosch stents. METHODOLOGY: Data were collected retrospectively on May 2000 to October 2008 on six patients with major bile duct injury secondary to cholecystectomy. All patients underwent surgical reconstruction with a Roux-en-Y hepaticojejunostomy and presented clinically as obstructive jaundice. Percutaneous transhepatic and/or endoscopic retrograde cholangiography, cholangioplasty by balloon dilation and biliary catheter placement were done in each patient prior to stents placement. Modified Gianturco-Rosch stents with 3cm length and 10mm diameter were used. Follow-up was obtained with direct patients contact or hospital records. RESULTS: Metallic stents were successfully implanted in all 6 patients and the mean patency rate was 46.5 months (range = 14-101 months). One patient required percutaneous recanalization procedure for recurrent cholangitis and obstruction. CONCLUSIONS: Gianturco-Rosch stents placement should be considered in patient with post-hepaticojejunostomy restenosis that repeat surgery is not feasible.

Magnetic resonance imaging of the long head of the biceps tendon: benefit of coplanar image.

PURPOSE: To evaluate coplanar imaging of the long head of the biceps tendon. METHODS: We retrospectively compared coronal oblique magnetic resonance images aligned with the principal supraspinatus tendon and with the intra-articular biceps tendon in 21 patients. Magnetic resonance images were analyzed for lesions depicted, including superior labral anteroposterior (SLAP) tears. Arthroscopic findings were reviewed. RESULTS: Coronal oblique images aligned with intra-articular biceps tendon depicted 18 (86%) of 21 coplanar intra-articular biceps tendons. Coplanar images identified 6 cases of tendinosis, 1 tear, 3 intra-articular ruptures, and 20 (95.2%) of 21 exact origins of the tendon. Arthroscopy revealed 18 SLAP tears. The detection of SLAP lesions between both coronal oblique magnetic resonance images was significantly different (P = 0.007). CONCLUSION: Advantages included imaging of the intra-articular biceps tendon with least partial-volume effects, definition of SLAP lesions and the tendinous origin at the supraglenoid tubercle, depiction of intra-articular bicipital ruptures, and increased sensitivity and specificity for intra-articular lesions.