No shinkei geka. Neurological surgery
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Under the title of anterior circulation aneurysms and the pterional approach, followings are presented and emphasized along with mentioning their historical development in our present performance status. Pterional approach: head positioning with Mayfield-Kees fixation apparatus using one pin around the processus matoideus and the other 2 pins on the contralateral side behind the hair line the head turned 30 degrees and reclined chin-up l5-20 grade. Skin incision beginning just in front of the tragus ending up at the midline hair line in a curvilinear fashion always including the superficial temporal artery STA in its frontal branch and the facial nerve (frontal branch) in the skin flap. ⋯ Its predilection site is at the medial anterior wall of the C1 portion but may occur also in any other portion of the ICA. (3) Middle cerebral artery MCA aneurysms; (a) For dissection, superior temporal gyrus ablation is not necessary but opening of the Sylvian fissure by retrograde tracing of a cortical artery on the surface of the temporal lobe. This cortical artery can be used as recipient when a bypass surgery turns out to be necessary with the use of a donor artery from the frontal branch of the STA. (b) Importance of interpreting DSA or 3DCT angiography in regard to whether the aneurysm dome is outside (lateral) or inside (medial) of the MCA bifurcation. This helps in anticipating whether the aneurysm dome or MCA branches come into view first at the time of intraSylvian dissection. (c) In case of presence of aneurysms at the contralateral MCA, accessibility from the ipsilateral side depends on the distance form the midline (for example early bifurcation), the relationship to the sphenoid wing (not below the level of the sphenoid wing) and no strong Sylvian vein darining into the sphenoparietal sinus being in the way.