RT Journal Article
SR Electronic
T1 Experimental Model of Dissecting Aneurysms
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 577
OP 584
VO 23
IS 4
A1 Okamoto, Takeshi
A1 Miyachi, Shigeru
A1 Negoro, Makoto
A1 Otsuka, Goro
A1 Suzuki, Osamu
A1 Keino, Hiroomi
A1 Yoshida, Jun
YR 2002
UL http://www.ajnr.org/content/23/4/577.abstract
AB BACKGROUND AND PURPOSE: The pathogenesis and optimal treatment for arterial dissection are still unclear. We devised an experimental model of arterial dissection and observed the morphologic changes with angiography.METHODS: Sixty-four experimental dissections were created in the common carotid arteries of 34 mongrel dogs. After a small incision was made in the arterial adventitia, it was dissected from the media. Elliptical defects (2, 4, 6, and 8 mm in groups I-A, I-B, I-C, and I-D, respectively; n = 47) or longitudinal incisions (4, 6, and 8 mm in groups II-A, II-B, and II-C, respectively; n = 17) were made in the intima distal to the adventitial incision to serve as an entry zone for dissection.RESULTS: Immediately after the lesions were created, the influx of blood into the dissected cavity produced massive subadventitial hematomas, resulting in stenotic changes in all of the arteries, including seven with occlusion. Follow-up (1-week) angiograms demonstrated complete healing, with normal arterial calibers in 11 (79%) of 14 I-A lesions and aneurysm formation in nine (69%) of 13 I-B lesions. All 10 I-D lesions had complete arterial occlusion. Persistent stenosis was observed in all 10 I-C lesions; six of these developed aneurysms. Pathologic examination of the freshly dissected cavities revealed a clot-filled cleft between the media and adventitia. Mature aneurysms, evaluated 3 mo later, had endothelialization within the aneurysmal dome.CONCLUSION: Morphologic changes after arterial dissection are closely related to the size of the intimal entry zone, which may determine whether a dissecting aneurysm forms.