Endovascular treatment of experimental aneurysms using a combination of thermoreversible gelation polymer and protection devices: feasibility study.
OBJECTIVE
We developed a new liquid embolic agent, an aqueous solution of thermoreversible gelation polymer (TGP) for the treatment of cerebral aneurysms. This polymer solution has the unique characteristics that allow it to solidify at a specific temperature without solvent. We performed an experimental aneurysm embolization using this liquid embolic agent with and without different protective devices to evaluate its technical feasibility for the treatment of aneurysms.


METHODS
Fourteen side-wall aneurysms were surgically constructed on 14 common carotid arteries of 7 swine. Embolizations were conducted in combination with balloon protection (balloon group, n = 4), microstent protection (stent group, n = 4), and microcoil and microstent protection (stent-coil group, n = 4). Two aneurysms were used as controls. One control aneurysm was not embolized, and the other received control stent placement only. Angiographic follow-up was performed on day 14 and was followed by histopathological evaluation.


RESULTS
Successful TGP solution delivery was conducted in all cases. Complete aneurysm occlusion was achieved in all cases without TGP migration. Follow-up angiograms demonstrated complete occlusion in the stent and stent-coil groups. A small recurrence was observed in the balloon group. Histopathological findings demonstrated neoendothelialization across the necks of the aneurysms.


CONCLUSIONS
Experimental aneurysms were safely embolized using TGP. Further modifications related to mechanical stability and long-term safety evaluation results are necessary before clinical application.
Takao
Hiroyuki
H
Division of Endovascular Neurosurgery, Department of Neurosurgery, Jikei University School of Medicine, Tokyo, Japan. takao@jikei.ac.jp
Murayama
Yuichi
Y
Yuki
Ichiro
I
Ishibashi
Toshihiro
T
Ebara
Masaki
M
Irie
Koreaki
K
Yoshioka
Hiroshi
H
Mori
Yuichi
Y
Vinuela
Fernando
F
Abe
Toshiaki
T
D000818:Animals; D002404:Catheterization / Q000379:methods; D002533:Cerebral Angiography / Q000379:methods; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D016503:Drug Delivery Systems / Q000295:instrumentation / Q000379:methods*; D004621:Embolization, Therapeutic / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D005780:Gelatin / Q000008:administration & dosage; D002532:Intracranial Aneurysm / Q000628:therapy*; D011145:Polyvinyls / Q000008:administration & dosage*; D015607:Stents; D013552:Swine; D013696:Temperature; D016896:Treatment Outcome
D011145:Polyvinyls; D005780:Gelatin