Sonographic assessment of splanchnic arteries and the bowel wall

Sonographic assessment of splanchnic arteries and the bowel wall

Abstracts / Clinical Imaging 32 (2008) 246–248 and after contrast administration. Before the examination, patents received oral polyethylene glycol (P...

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Abstracts / Clinical Imaging 32 (2008) 246–248 and after contrast administration. Before the examination, patents received oral polyethylene glycol (PEG) (1000 ml for adults; 10 ml/kg of body weight for children). Regions of interest (ROIs) were placed on the normal and diseased intestinal wall to assess signal intensity and rate of increase in contrast enhancement over time. Data were compared with the Crohn's Disease Activity Index (CDAI). Results: The diseased bowel wall showed early and intense uptake of contrast that increases over time until a plateau is reached. In patients in the remission phase after treatment, signal intensity was only slightly higher in diseased bowel loops than in healthy loops. There was a significant correlation between the peak of contrast uptake and CDAI. Conclusions: Dynamic MRI is a good technique for quantifying local inflammatory activity of bowel wall in patients with Crohn's disease. Can independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners be used for primary interpretation of MDCT of the abdomen and pelvis? A feasibility study Sebastian S, Kalra MK, Mittal P, Saini S, Small WC (Department of Radiology, Emory University School of Medicine, 1364 Clifton Road NE, Atlanta, GA 30322). Eur J Radiol 2007;64:439­446. Purpose: To evaluate if coronal reformatted images can be used for primary interpretation of MDCT of the abdomen and pelvis using 64-slice MDCT. Materials and methods: IRB approval was obtained. We reviewed MDCT studies of the abdomen and pelvis of 220 consecutive patients performed with 64-row MDCT with constant scanning parameters. Based on a 0.625mm raw data set, transverse images were reconstructed at 5 mm and coronal images at 3 mm using standard reconstruction algorithms. Reader familiarity was achieved by simultaneous evaluation of transverse and coronal reformats in an initial group of 20 separate cases for findings in consensus. Two subsequent phases of image analysis were then performed in two groups of 100 patients each. In the first phase, two radiologists evaluated the added utility of simultaneous review of MDCT of transverse and coronal reformatted images over transverse images alone in 100 consecutive patients referred for MDCT of the abdomen and pelvis. In the second phase, the same radiologists evaluated whether coronal multiplanar reformats could be used for primary interpretation of MDCT of the abdomen and pelvis in a separate but similar cohort of 100 consecutive abdominopelvic MDCT studies. The number of lesion(s), their location, size of smallest lesion, presence of artifacts, and likely diagnosis were noted at each image interpretation. Image quality and confidence for interpretation was evaluated using five-point and three-point scale, respectively. The time required for primary interpretation of coronal reformats and transverse images were recorded. Statistical analysis was performed using Wilcoxon signed rank test. Results: Both readers detected additional findings (n=37, 35), respectively, on simultaneous review of transverse and coronal reformats as compared with transverse images alone (pb0.001). Excellent interobserver agreement was noted (r=0.94–0.96). Both readers detected additional findings (n=62, 53), respectively, on independent review of coronal reformats as compared with transverse images alone (Pb.001). Readers' confidence was also found to be higher on coronal evaluations as compared to axial images (Pb.01). There was good interobserver agreement between the two readers. Conclusion: Independent coronal multiplanar reformatted images obtained using state-of-the-art MDCT scanners show promise as the preferred orientation and can be useful for primary interpretation of MDCT of the abdomen and pelvis.

Quantification of missing and overlapping data in multiple-hold abdominal imaging Noterdaeme O, Gleeson F, Phillips RR, Brady M (Wolfson Medical Vision Laboratory, Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, UK). Eur J Radiol 2007;54:273­278. Magnetic resonance imaging (MRI) of the abdomen is often performed in multiple breath holds which are designed to contiguously cover the region of

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interest. This technique may result in a failure to image all the appropriate area, and the extent of this failure is difficult to appreciate on a set of 2D slices. With reference to three patient cases, we present a method to quantify the extent of this problem and suggest a solution. First, we manually delineate the region of interest on a single breath hold fast spoiled gradient echo (FSPGR) sequence. Subsequently, we align images acquired in separate breath holds to this reference volume. A colored 3D presentation makes the extent of unimaged and repeatedly imaged areas clearly visible to the clinician. The alignment also helps radiologists to accurately determine the location of individual slices. The described method can easily be automated and is ideally implemented at the scanner console, ensuring the availability of contiguously sampled data sets to radiologists with minimum user interaction from the radiographer. Such data sets enable the deployment of robust 3D analysis algorithms.

Sonographic assessment of splanchnic arteries and the bowel wall Dietrich CF, Jedrzejczyk M, Ignee A (Innere Medizin 2, Caritaskrankenhaus Bad Mergentheim, Uhlandstrasse 7, D-97980 Bad Mergentheim, Germany). Eur J Radiol 2007;64:202­212. The intestinal wall can be visualized using high-resolution transabdominal ultrasound. The normal intestinal wall thickness in the terminal ileum, cecum, and right and left colon is b2 mm when examined with graded compression. It is important to appreciate that a contracted intestinal segment can be misinterpreted as a thickened wall. Vascularisation can be mainly displayed in the second hyperechoic layer (submucosal layer) as well as vessels penetrating the muscularis propria. Imaging of the gastrointestinal wall is dependent on the experience of the examiner as well as dependent on the equipment used. Acute or chronic inflammation of the intestinal wall is accompanied by increased perfusion of the mesentery, which can be displayed nonquantitatively with colour duplex. In contrast, ischemia is characterised by hypoperfusion of the mesenteric arteries and the bowel wall. The most promising sonographic approach in assessing splanchnic arteries and the bowel wall is combining the analysis of superior and inferior mesenteric inflow by pulsed Doppler scanning (systolic and diastolic velocities, resistance index) with the end-organ vascularity by colour Doppler imaging diminishing the influence of examination technique only displaying bowel wall vascularity. Colour Doppler imaging has been described as helpful in a variety of gastrointestinal disorders, particularly in patients with Crohn's disease, celiac disease, mesenteric artery stenosis and other ischemic gastrointestinal diseases, graft versus host disease and hemorrhagic segmental colitis.

Bone marrow edema of the femoral head Vande Berg B, Lecouvet P, Koutaissoff S, Simoni P, Maldague B, Malghem J (Department of Medical Imaging, Cliniques Universitaries St Luc, UCL, 10 avenue Hippocrate B-1200 Brussels, Belgium). J Belge Radiol 2007;90:350­357. This article addresses the MR features of the bone marrow edema syndrome (BMES) of the femoral head with emphasis on the prevalence and clinicopathology of the disorder and description of the current concepts on diagnosis and prognosis. BMES can be observed in self-resolving conditions such as transient osteoporosis of the hip, spontaneous fracture of the femoral head, or post traumatic lesions. Rapidly destructive coxarthrosis, necrosis of the femoral head as well as certain forms of spontaneous fracture of the femoral head may present a similar MR pattern, though prognosis is definitely less favourable. The challenging role of the radiologist is to recognize BMES at an early stage and to provide adequate prognosis on the lesion outcome.

MR arthrography in glenohumeral instability Van der Woude H-J, Vanhoenacker FM (Department of Radiology, Onze Lieve Vrouwe Gasthuis Amsterdam, P.O. Box 95500, NL 1090 HM Amsterdam, The Netherlands). J Belge Radiol 2007;90:377-383.