Large and Giant Paraclinoid Aneurysms: Surgical Techniques, Complications, and Results

Abstract

Twenty-five patients with giant (greater than 25 mm in diameter) and 9 patients with large (15 to 25 mm in diameter) aneurysms of the internal carotid artery in the ophthalmic or paraophthalmic region are reviewed. In 23 of these patients the aneurysm was clipped directly. There was 1 death in this group, and none of the survivors had disabling neurological complications outside the visual system. The other 11 patients were treated by a trapping procedure or by either common carotid ligation or internal carotid ligation in the neck. Of the 5 patients treated by internal carotid ligation preceded by an extracranial to intracranial bypass graft, 3 developed embolic complications, which in 1 patient resulted in death. One of the 4 patients treated by ligation of the common carotid artery died 1 year later from a recurrent subarachnoid hemorrhage. Of the total group, 18 patients had visual loss preoperatively as a result of aneurysmal compression; in 10 the vision was improved by operation, in 3 it was made worse, and in 2 it was unchanged. In another patient the vision continued to deteriorate slowly after common carotid occlusion, and the other 2 patients died postoperatively before vision could be assessed. The complications in the patients are described and analyzed in detail. Maneuvers found to be of value in the direct approach to these lesions are described. Of these, exposure of the internal carotid artery in the neck for temporary occlusion during clipping and thorough drilling of the anterior clinoid process and unroofing of the optic canal were particularly helpful. The literature on indirect methods of treatment by carotid occlusion with and without bypass graft is reviewed with special reference to the complications and effectiveness of each alternative. Based on this review of the literature and our experience, a treatment scheme is suggested for these aneurysms depending on their mode of presentation.

Role of superior hypophyseal artery in visual function impairment after paraclinoid carotid artery aneurysm surgery

“…Visual deficits associated with clipping surgery for paraclinoid carotid artery aneurysm can be caused by vascular compromise, manipulation of the optic nerve, thermogenic effects from high-speed drilling of the clinoid process, or other unknown causes. 3,5,6,10,19,20 For the patient in Case 2, surgical manipulation was the most likely cause of the postoperative visual worsening because VEPs were attenuated during the suction decompression procedure.…”

“…However, postoperative visual complications may be caused by ischemia associated with SHA sacrifice. [3][4][5][6]9,10,20 In 2007, Goto et al 9 reported that the temporary occlusion of the SHA in the contralateral approach for SHA aneurysms attenuated VEPs and that the preservation of the SHA avoided vision complications. This report indicates a possibility that a unilateral SHA supplies the bilateral optic apparatus or that no circumferential anastomosis is present between right and left SHAs in rare cases.…”

Large Paraclinoid Aneurysm With a Calcified Neck Treated by Tailored Multimodality Procedures-Case Report-

“…2,4,6,8,17) However, occlusion or stenosis of the ipsilateral ICA sometimes occurs after direct clipping and a high degree of mural sclerosis of the aneurysms and the parent artery is suspected to be one of the most crucial predictors of this phenomenon. 13,14,16,24) In our case, the severe calcification of the aneurysm neck led us to avoid direct clipping. Drilling of the anterior clinoid process often induces postoperative aggravation of the visual loss or visual field defect due to mechanical or heat injury.…”

“…Recent advances in skull base surgery have enabled direct clipping of the aneurysm. 2,4,6,8,13,17) The use of endovascular surgery has also increased, but the results of endosaccular coil embolization may be less satisfactory for wide-necked aneurysms or aneurysms causing a mass effect. 3,7,[9][10][11]14,[20][21][22][23] Direct clipping sometimes results in incomplete obliteration of the aneurysm or compromise of the patency of the ICA if severe sclerotic change is present in the wall of the aneurysm neck or the parent artery.…”

“…3,7,[9][10][11]14,[20][21][22][23] Direct clipping sometimes results in incomplete obliteration of the aneurysm or compromise of the patency of the ICA if severe sclerotic change is present in the wall of the aneurysm neck or the parent artery. 13,14,16,24) We report a case of large paraclinoid aneurysm with a calcified neck treated by a tailored combination of multimodality procedures.…”