Table 1.

Comparison of models of ischemia

	Complete Vascular Occlusion
	SMA Ligation	SMA Embolization	Low-Flow	Segmental Vascular Occlusion
Advantages	Models occlusive causes of ischemia Ease of surgical model creation	Models occlusive causes of ischemia Intestinal tract not exposed or manipulated (1, 25, 96, 148) Ideal for diagnostic imaging studies	Models nonocclusive causes of ischemia Improved model of reperfusion injury	Models occlusive causes of ischemia Creation of multiple loops of varying duration of ischemia within a single animal Applied in human subjects (46, 47, 73–75, 115) Both arterial and venous supply ligated; most clinical cases of strangulating ischemia venous supply obstructed first
Disadvantages	Poor model of chronic ischemia Only arterial supply occluded Unreliable to create consistent injury (116) High mortality rate (116) No reduction of blood flow to distal colon (142) Different segments of intestine vary in resistance to ischemic injury (37, 107, 147)	Poor model of chronic ischemia Only arterial supply occluded Requires advanced surgical approach Likely requires large animal Ischemia not reversible, prohibiting study of reperfusion	Increase difficulty of surgery Minimal ischemic injury

SMA, superior mesenteric artery.