Diagnosis Of Small Bowel Disease With Air-infused MR Enteroclysis And Hydr-MRI

1. PURPOSE:To investigate the technique of air-infused MR enteroclysis and hydro-MRI and their value in diagnosis of small bowel disease.2. MATERIAL AND METHODS:(1). Group division: 38 patients with suspected small bowel disease received small-bowel magnetic resonance imaging(MRI).15 patients underwent air-infused MR enteroclysis (group of air-infused enteroclysis), and the other 23 patients underwent small bowel hydro-MRI(group of hydro-MRI). To distend the small bowel, about 1000ml of air was infused into the small bowel of the patients of air-infused enteroclysis through a nasoenteric tube, and 1500ml of 2.5% osmotic mannitol was ingested in the 22 patients of hydro-MRI and 1 patient with severe small bowelobstruction used directly the intraluminal solution.(2) . Methods and sequences of examination: Before MRI, all patients received 20 mg of IV anisodamine to reduce small-bowel peristalsis except the patient with severe small bowel obstruction. Fat-saturation was used in all sequences. The MRI sequences included: a. Group of air-infused enteroclysis, Gd-DTPA enhanced coronal and axial T1-weighted spin-echo(SE) sequence and fast spoiled gradient echo(FSPGR) sequence, b. Group of hydro-MRI, coronal T2-weighted singl e-shot fast SE (SSFSE), Tl weighted coronal FSPGR and enhanced coronal and axial FSPGR and SE sequences.(3). Comparison: Comparison between the diagnosis of MRI and the results of surgery, pathology or clinic was performed, and the image characteristic of the two kinds of small bowel MRI was assessed.3.RESULTS:(1): In group of air-infused MR enteroclysis, there were 5 case of normal small bowel, 5 Crohn' s disease, 2 gastric intestinal stromal tumor(GIST), lymphoma, tuberculosis and irritable bowel syndrome 1 case, respectively. In group of hydro-MRI, there were 9 cases of small bowel were normal, 7 Crohn' s disease, 2 small bowel obstruction(caused by tumor and inflammatory bowel disease, respectively), duodenal tumor, duodenitis, duodenocolic fistula ,small intestinal capillary telangietasia and small intestinal malrotation 1 case,espectively. Except 1 Crohn' s disease was diagnosed as lymphoma and no abnormality was found in 1 intestinalcapillary telangietasia and 1 irritable bowel syndrome, the other diagnosis of MRI was correct.(2). Because of no breath and sensibility artifact, the quality of breath-hold scanning images of hydro-MRI is superior to that of SE sequence and air-infused MR enteroclysis, and the small bowel wall in the breath-hold scanning image of enhanced fat-saturated FSPGR sequence is the clearest.4.CONCLUSION:(1). Small bowel MRI is of important value to diagnose Crohn' s disease, small bowel tumor and to differentiate the reason of small bowel obstruction;(2). hydro-MRI with oral osmotic mannitol is superior to air-infused MR enteroclysis.