Türk Nöroşirürji Dergisi
2001 , Vol 11 , Num 3
THE COURSE VANATIONS OF THE ABDUCENS NERVE AT THE PETROCLIVAL REGION: AN ANATOMICAL CADAVERIC STUDY
1Fırat Üniversitesi Tıp Fakültesi, Nöroşirürji, A.B.D., Elazığ2Fırat Üniversitesi Tıp Fakültesi, Patoloji, A.B.D., Elazığ
3Ankara Üniversitesi Tıp Fakültesi Anatomi A.B.D., Ankara
4Ankara Üniversitesi Tıp Fakültesi Anatomi Nöroşirürji A.B.D., Ankara N. abducens usually extends as one nerve trunk in its course between the brain stem and the lateral rectus muscle. However, sometimes it passes this distance by dividing into two fascicles. Double abducens nerve variations were found in three cadavers, and were studied through microanatomical dissection. Double abducens nerve variation was seen on one side (right) in two and on both (right and left) sides in one cadaver. Double sixth nerves were originated as one nerve trunk from the brain stem, then divided into two fascicles in the subarachnoid space, and then they joined as one nerve trunk again in the cavernous sinus to innervate the lateral rectus muscle. Both fascicles of the double abducens nerves of the both sides were arised from the pontomedullary sulcus as two separate branches, and were joined in the cavernous sinus to form one trunk for innervation of the lateral rectus muscles on the third cadaver. Both fascicles were passed below the petrosphenoidalligament in three cadavers. During their course between the dural entrance porus and the lateral wall of the cavernous segment of the internal carotid artery, it was found that both nerve fascicles were surrounded by the arachnoid membrane inside and by the dura mater outside, respectively; and this finding was confirmed through the histological sections in one cadaver. Awareness of the double sixth nerve has an importance in prevention of the possible abducens nerve complication during the interventions to the petroclival and cavernous sinus regions. Anahtar Kelimeler : Arachnoid membrane, double abducens nerve, dura mater, petrosphenoida lligament