Correlation of Cross Sectional Imaging and Small Intestinal Contrast Ultrasonography in Known Crohn's Disease

Diagnosis, CD site and patient's management shall be made according generally accepted recommendations(4). SICUS shall be performed in all participants by one independent experienced operator (MAM). Colonic cleansing shall be done on night before the examination with Polyethylene glycol (PEG) solution (1 litre). The participants shall be examined after the ingestion of 375 mL (range 250-500 mL) of polyethylene glycol (PEG) in the morning using a convex transducer (2-6 MHz) and a high frequency linear-array transducer for details (5-14 MHz). Median SICUS duration shall be noted. SICUS shall be performed without any additional charges to the participant. CT-Enteroclysis shall be performed in all participants by one independent experienced operator (UK). A 20G needle shall be placed in an antecubital vein and 8-F nasojejunal catheter with aTeflon-covered guide wire shall be positioned under fluoroscopic guidance with the distal extremely located in the distal duodenum/proximal jejunum. Afterward the patient shall be taken into the CT room where hypodense contrast material (1500 mL of PEG) shall be administered manually with 60-mL syringes, with a constant and continuous injection rate of 150 mL/min followed by a flow rate of 200 mL/min until the maximum tolerance of the patient. Just before the examination participants shall receive a smooth muscle relaxant (N butyl 4 scopolamine) to prevent spasms, achieve uniform small bowel distension, and reduce abdominal discomfort. The study shall be performed by a 64-slice multidetector CT with the following scan parameters: collimation 1.25 mm, table feed 39.37 mm/rot, 120 kV, 300 mAs,pitch 0.984:1, rotation time 0.5 s, time of acquisition 12.5 s, FOV 50 cm, matrix 512x512. After the infusion of PEG, CT scan seal be performed before and after the administration of intravenous iodinated contrast material. The contrast-enhanced study shall be acquired 70s after the administration of contrast material (Ultravist 370, Schering AG, Berlin, Germany). Median CT-Enteroclysis duration shall be recorded. Magnetic Resonance enterography (MRE) shall be performed in all participants by one independent experienced operator. The participant shall be fasted for 4-6 h prior to the study. In adults, 2 liters of oral fluid with mannitol shall be administered to distend the bowel loops. Just before the examination participants shall receive a smooth muscle relaxant (Buscopan) to prevent spasms, achieve uniform small bowel distension, and reduce abdominal discomfort. T2, BTFE(axial and coronal sequence),diffusion weighted imaging (DWI)(Coronal sequence), Post contrast (Axial, Coronals and sagittal sequence) will be taken.Median MRE duration shall be recorded.The site of small bowel involvement, maximal bowel wall thickness and complications like stricture and fistula detected by SICUS and MRE/CTE shall be collected and correlated.

Inclusion criteria

• Patients with known small bowel CD beyond reach of standard endoscopy who warrants monitoring of disease status either due to assessment of response to therapy/relapse/new unexplained symptoms, persistent disease activity, prior to switching therapy or deciding on surgical management.

Exclusion criteria

• Obese patients with poor ultrasound window
• pregnant/lactating mother
• Not willing for CT or enteroclysis examination
• Renal insufficiency precluding CT