Can neck size in elastase-induced aneurysms be controlled? A prospective study.

BACKGROUND AND PURPOSE An earlier retrospective study indicated that the neck size of elastase-induced aneurysms could be controlled by adjusting the position of the inflated balloon. We report the current prospective study to confirm our previous work. METHODS Ninety elastase-induced aneurysms were created in rabbits. Group 1 (n = 62) included cases in which the occlusion balloon resided low, completely within the brachiocephalic/subclavian arteries. Group 2 (n = 28) included cases in which the balloon resided high, within both the common carotid artery and brachiocephalic/subclavian arteries. Follow-up digital subtraction angiography was performed. The aneurysm sizes were measured and compared between groups. The Student t test and the Fisher exact test were used for statistical analysis. RESULTS The mean aneurysm neck diameter and width for group 1 was significantly larger than that of group 2 (3.4 +/- 1.2 and 2.3 +/- 0.9 mm, P < .001; 3.8 +/- 1.0 and 3.3 +/- 0.9 mm, P < .05, respectively). The proportion of wide-necked aneurysms in group 1 was significantly larger than that in group 2 (29% vs 4%; P < .005). Mean dome-to-neck ratios were 1.2 +/- 0.4 and 1.7 +/- 0.7 for groups 1 and 2 (P < .005). There was no significant difference in aneurysm height between groups 1 and 2 (8.0 +/- 1.7 and 7.5 +/- 2.2 mm; P > .05). CONCLUSION The neck size of elastase-induced aneurysm models in rabbits can be controlled by adjusting the position of the inflated balloon.