The bipolar coagulator has been frequently used in reducing the size of aneurysaml neck or dissecting the aneurysmal sac. However the effects of bipolar current on the wall of vessels have not been adequately documented. The author studied the
histopathological changes of arterial wall after bipolar coagulation.
Thirty one Sprague-Dawley strain rats of both sexes and of various age were used. Under pentobarbital anesthesia, the left renal artery was coagulate with bipolar forcep just distal to it's origin from the aorata. The tats were divided into two
group :
Group A was coagulated for one second; Group B for two seconds. The coagulation sites of the vessels were examed grossly and microscopically in three and six months, respectively.
@ES The results were summerized as followings :
@EN 1. In both three and six month groups : the internal elastic membrane and elastic fibers were destructed, fragmented, and thinned ; the medial smooth muscle cells were damaged and decreased in number.
2. While the ecdothelial cells were severely desquamated and scattered in three month group, but there was an evidence of partial regeneration of endothelium and reduction of inflammatory reaction in six month group. Fibrosis was more augmented
in
six
month group than three month group.
3. Between group A and B, there seemed to be no definite discrepancy in histopathological findings.
4. Pseudoaneurysms were developed in 72.2% of three month group and in 61.5% of six month group, but there was no significant statistical difference in the rate of pseudoaneurysm formation between two groups (p>0.05, γ2=0.393)
5. Above findings suggest that the pseudoaneurysm which might be produced by bipolar coagulation of vessels in the neurosurgical operation, would be progressed to the aneurysm if continuous hemodynamic factors are exerted upon the
pseudoaneurysm.
Therefore, it is desirable that the bipolar current should e used very cautiously during the surgery of cerebrovascular disease.
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