Comparison of cellulose acetate polymer and electrolytic detachable coils for treatment of canine aneurysmal models.
OBJECTIVE
Electrolytic detachable coils (EDC) have been the main embolic materials for intracranial aneurysms. Liquid aneurysmal embolic materials represented by cellulose acetate polymer (CAP) are still in controversy. In this research, the embolization results and pathological reactions after embolization of canine aneurysmal models with EDC or CAP were observed and compared.


METHODS
The canine aneurysmal models constructed by anastomosis of venous pouches were randomly grouped. The aneurysms were respectively occluded with CAP and electrolytic detachable coils that was named by Wu electrolytic detachable coil (WEDC) and made by us. Angiogram follow-ups were performed at 24-hour, 2-week, and 2-month after embolization. The occluded aneurysms were dissected in each stage for light microscopic, electron microscopic, and histochemical research.


RESULTS
The effect of embolization was significantly better with WEDC than that with CAP (chi2 = 5. 56, P < 0.05). Post-embolized complications such as aneurysm rupture and stenosis of parent arteries could only be found in CAP group. Pathological research showed that CAP mass could packed the aneurysms more densely than coils. Acute chemical damage of aneurysmal wall and inflammatory cell infiltration was prominently found in early stage after CAP-embolization. Organization of thrombus inside aneurysms and formation of endothelial tissue over the orifices of aneurysmal necks could be found in both groups 2 months after embolization. But parts of coils might be exposed outside endothelial layer.


CONCLUSIONS
EDC are still the most safe, efficient, and reliable instruments to embolize aneurysm. CAP should be improved further to solve the problem of strong chemical corrosion and difficulty in control before it is widely used.
Yang
Xinjian
X
Beijing Neurosurgical Institute, Beijing 100050. yang-xj@163.net
Wu
Zhongxue
Z
Li
Youxiang
Y
Sun
Yilin
Y
Yin
Ke
K
D000818:Animals; D001672:Biocompatible Materials; D002482:Cellulose / Q000031:analogs & derivatives*; D004285:Dogs; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D002532:Intracranial Aneurysm / Q000628:therapy*; D008297:Male; D011897:Random Allocation; D014414:Tungsten
D001672:Biocompatible Materials; C005062:acetylcellulose; D002482:Cellulose; D014414:Tungsten