Published online Oct 28, 2013. doi: 10.3748/wjg.v19.i40.6825
Revised: July 27, 2013
Accepted: August 17, 2013
Published online: October 28, 2013
Processing time: 163 Days and 6.9 Hours
AIM: To explore the physiopathology and magnetic resonance imaging (MRI) findings in an animal model of acute arterial mesenteric ischemia (AAMI) with and without reperfusion.
METHODS: In this study, 8 adult Sprague-Dawley rats underwent superior mesenteric artery (SMA) ligation and were then randomly divided in two groups of 4. In group I, the ischemia was maintained for 8 h. In group II, 1-h after SMA occlusion, the ligation was removed by cutting the thread fixed on the back of the animal, and reperfusion was monitored for 8 h. MRI was performed using a 7-T system.
RESULTS: We found that, in the case of AAMI without reperfusion, spastic reflex ileus, hypotonic reflex ileus, free abdominal fluid and bowel wall thinning are present from the second hour, and bowel wall hyperintensity in T2-W sequences are present from the fourth hour. The reperfusion model shows the presence of early bowel wall hyperintensity in T2-W sequences after 1 h and bowel wall thickening from the second hour.
CONCLUSION: Our study has shown that MRI can assess pathological changes that occur in the small bowel and distinguish between the presence and absence of reperfusion after induced acute arterial ischemia.
Core tip: Diagnosis of acute arterial mesenteric ischemia depends on early detection and findings with regarding the presence or absence of reperfusion events. Distinguishing between these different conditions is crucial to improving outcome for the patient and represents a challenge for radiologists. The results of this preliminary study in an animal model provide for a time-based definition of the radiological findings in ischemia and reperfusion, showing that magnetic resonance imaging can adequately assess the different pathological changes that occur in acute arterial mesenteric ischemia with or without reperfusion.