Recanalization and particle exclusion after embolization of uterine arteries in sheep: a long-term study.
OBJECTIVE
To compare the long-term evolution of uterine arteries after embolization with the two most commonly used embolic agents for fibroid embolization: nonspherical polyvinyl alcohol (PVA) particles and trisacryl gelatin microspheres (TGMS).


METHODS
Prospective study.


METHODS
University-based interventional radiology, pathology, and reproductive physiology units.


METHODS
Two groups of 10 sheep embolized in the uterine artery.


METHODS
Embolization of the uterine artery with either 600-1000 microm nonspherical polyvinyl alcohol (PVA) particles or with 700-900 microm trisacryl gelatin microspheres (TGMS). Animals were synchronized and naturally inseminated. Animals were killed at 26 months.


METHODS
Uteri were examined pathologically for vessel size, site of occlusion, recanalization rate of vessels, and particle location within the vascular wall.


RESULTS
The PVA particles were more numerous in the vessels' lumen than the TGMS particles (13.3 +/- 20.8 vs. 2.5 +/- 2.7), were located more proximally than TGMS (97% vs. 68% in the trunk and first branches of the uterine artery), and were found almost exclusively in the intima (99.2%). In contrast, 54.4% of the TGMS particles were found in the intima, and 45.6% partially or totally excluded. The rate of recanalization was not statistically significantly different for PVA and TGMS (65.2% vs. 60.6%).


CONCLUSIONS
The long-term evolution of uterine arteries was different after uterine artery embolization with PVA and TGMS because PVA particles formed large-sized aggregates that occluded proximal vessels and remained in the vessel intima. Microspheres occluded more distal vessels, and about 50% of them were partially or totally excluded from the vessel.
Laurent
Alexandre
A
Department of Interventional Neuroradiology, AP-HP, Lariboisière Hospital, Paris, France.
Wassef
Michel
M
Namur
Julien
J
Martal
Jacques
J
Labarre
Denis
D
Pelage
Jean-Pierre
JP
D000180:Acrylic Resins / Q000008:administration & dosage* / Q000009:adverse effects / Q000378:metabolism; D000818:Animals; D001158:Arteries / Q000378:metabolism / Q000473:pathology; D005260:Female; D005298:Fertility; D005549:Foreign-Body Reaction / Q000209:etiology / Q000473:pathology; D005780:Gelatin / Q000008:administration & dosage* / Q000009:adverse effects / Q000378:metabolism; D023421:Models, Animal; D010316:Particle Size; D011142:Polyvinyl Alcohol / Q000008:administration & dosage* / Q000009:adverse effects / Q000378:metabolism; D011247:Pregnancy; D011446:Prospective Studies; D012756:Sheep; D013997:Time Factors; D055357:Uterine Artery Embolization / Q000009:adverse effects / Q000379:methods*; D014599:Uterus / Q000098:blood supply* / Q000473:pathology / Q000503:physiopathology
D000180:Acrylic Resins; C496735:trisacryl gelatin microspheres; D005780:Gelatin; D011142:Polyvinyl Alcohol