Michael Macari MD, Abstract Co-Author: Nothing to Disclose

Bradley Spieler, Presenter: Nothing to Disclose

Darius Biskup, Abstract Co-Author: Nothing to Disclose

Alec Jeffrey Megibow MD, MPH, Abstract Co-Author: Consultant, E-Z-EM, Inc, Westbury, NY Medical Advisory Board, Siemens AG, Malvern, PA

James S. Babb PhD, Abstract Co-Author: Nothing to Disclose

To determine the normal size of the ampulla of Vater at CTE.

IRB approval was obtained. From 12/1/2006 until 2/24/2007 80 patients underwent CTE. Indications were nonspecific abdominal pain (n=51), pancreatic/biliary pathology (n=11), Crohn’s disease (n=6), other (n=12). Patients ingested two 450 ml bottles of VoLumen 30 and 20 minutes prior to CTE. 225 ml of water were consumed 10 minutes and immediately prior to CTE. Total volume was 1350 ml. 0.1 mg of Glucagon was administered and 1.5 ml/kg of iodinated contrast was injected at 4 ml/second. CT data were acquired on a 64 row scanner with .6 mm detector configuration and 4 mm axial and 3 mm coronal images were sent to PACS. Data were evaluated for duodenal distension (collapsed, moderately, and well distended) and the size of the papilla on axial and coronal images. Normal papilla size was described by the mean ± standard deviation and the range. The Pearson correlation coefficient and 95% limits of agreement were used to describe the association of sizes on axial and coronal images.

Eleven patients were excluded because of pancreatic/biliary pathology. 69 cases of CTE were thus available. Duodenal distension was graded as collapsed (n=24; 34.8%), moderate (n=17; 24.6%), and well distended (n=28; 40.6%). In cases where the duodenum was moderately or well distended the mean ± standard deviation of the papilla was 0.658 ± 0.184 cm (0.3 to 1.14 cm) on axial images and 0.657 ± 0.175 cm (0.3 to 1.10 cm) on coronal images. The size assessments from the axial and coronal images had a correlation of 0.892 with 95% limits of agreement of ± 0.025 cm (3.8% of the mean size). Given these findings we are 95% confident that the size of the normal papilla will not exceed 1.03 cm on either axial or coronal images.

The size of the normal ampulla ranged between 0.3 and 1.14 cm and the normal size is expected to be less than 1.03 cm for 95% of subjects.

CT enterography is being utilized with increasing frequency and the ampulla of Vater is often seen. Knowledge of its normal size is important to avoid over errors in interpretation.

Macari, M, Spieler, B, Biskup, D, Megibow, A, Babb, J, The Normal of Papilla of Vater: Observations at CT Enterography.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5003552.html