Maansi Rajul Parekh MBBS, Presenter: Nothing to Disclose

Anirudh Kohli MD, DMRD, Abstract Co-Author: Nothing to Disclose

Deepak Rajput MD, Abstract Co-Author: Nothing to Disclose

Rohan Subhash Kashyape MD, Abstract Co-Author: Nothing to Disclose

To evaluate the use of mannitol as an oral contrast agent to provide distension of small bowel to detect small bowel pathologies and obviate the need for small bowel enteroclysis. Further to evaluate the possibility to use mannitol as an oral contrast agent universally replacing iodinated oral contrast agents.

1000-1500 ml of 2% oral mannitol administered to the patient.MDCT of the abdomen and pelvis were performed in 560 patients using dual source 64 slice dual energy Siemens CT scanner – Definition . A multiphase scan consisting of plain, early and late arterial, venous and delayed phases with intravenous contrast was performed for each patient. Contraindications for mannitol intake included obstruction, suspected leak/perforation and postoperative status.

Oral mannitol produces adequate distension of the abdomen .Conditions like Crohns disease, angiodysplasia, carcinoids and strictures were likely to be missed if mannitol had been substituted with positive oral contrast.In 560 patients administered oral mannitol 24 developed more than 4 loose stools after administration of 2% mannitol .However this was self limiting and no treatment was required while 6 patients developed diarrhea for which intravenous hydration and monitoring was required.

Oral mannitol is palatable, cheap, easy to prepare,has better luminal distension than oral positive contrast,allows optimal differentiation between lumen and bowel wall and is of importance in CT abdominal angiographies in differentiation between bowel and blood vessels. Subtle mucosal enhancement during arterial and venous phases can be demonstrated in vascular, inflammatory, infective and neoplastic pathologies which cannot be seen with positive contrast.The small bowel remains the most challenging region to visualize due to overlap of bowel loops. CT enteroclysis using methylcellulose requires nasojejunal tube placement. CT enterography can obviate this need and hence is more acceptable to the patient. Positive oral contrast produces attenuation of lumen of higher values and often does not produce adequate distension.

Mannitol produces optimal distension allowing visualization of the wall,intra and extraluminal pathologies due to mucosal enhancement thus replacing need of CTenteroclysis and iodinated contrast media

Parekh, M, Kohli, A, Rajput, D, Kashyape, R, Evaluation of Mannitol as an Oral Contrast Agent in Evaluation of Small Bowel Pathologies, Thus Obviating the Need of CT Enteroclysis and Further Its Use in Replacement of Iodinated Oral Contrast Agents.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9014334.html