C ranial nerve splitting or infiltration by intracranial aneurysms has been reported in the literature. Typically, this anomaly has been seen with the optic nerve or chiasm and involvement with ophthalmic artery or anterior communicating artery aneurysms. The authors describe the first reported case of a PCA aneurysm arising from a duplicated arterial branch that was found to be splitting the oculomotor nerve. Case Report History, Presentation, and Examination This 63-year-old man experienced the sudden onset of the “worst headache of his
Mandy J. Binning and William T. Couldwell
William T. Couldwell and Roukoz Chamoun
Dorsal variant proximal carotid blister aneurysms are treacherous lesions to manage. It is important to recognize this variant on preoperative angiographic imaging, in anticipation of surgical strategies for their treatment. Strategies include trapping the involved segment and revascularization if necessary. Other options include repair of the aneurysm rupture site directly. Given that these are not true berry aneurysms, repair of the rupture site involves wrapping or clip-grafting techniques. The case presented here was a young woman with a subarachnoid hemorrhage from a ruptured dorsal variant blister aneurysm. The technique used is demonstrated in the video and is a modified clip-wrap technique using woven polyester graft material. The patient was given aspirin preoperatively as preparation for the clip-wrap technique.
It is the authors' current protocol to attempt a direct repair with clip-wrapping and leaving artery sacrifice with or without bypass as a salvage therapy if direct repair is not possible. Assessment of vessel patency after repair is performed by intraoperative Doppler and indocyanine green angiography. Intraoperative somatosensory and motor evoked potential monitoring is performed in all cases.
The video can be found here: http://youtu.be/crUreWGQdGo.
William T. Couldwell and Jayson A. Neil
Ruptured fusiform posterior inferior cerebellar artery (PICA) aneurysms can be technically challenging lesions. Surgeons must be ready to employ a variety of strategies in the successful treatment of these aneurysms. Strategies include complex clip techniques including clip-wrapping or trapping and revascularization. The case presented here is of a man with subarachnoid hemorrhage from a fusiform ruptured PICA aneurysm. The technique demonstrated is a far-lateral approach and a clip-wrap technique using muslin gauze. The patient was given aspirin preoperatively in preparation for possible occipital–PICA bypass if direct repair was not feasible. It is the authors' preference to perform direct vessel repair as a primary goal and use bypass techniques when this is not possible. Vessel patency was evaluated after clip-wrapping using intraoperative Doppler. Intraoperative somatosensory and motor evoked potential monitoring is used in such cases. The patient recovered well.
The video can be found here: http://youtu.be/iwLqufH47Ds.
William T. Couldwell
Background: The first-degree relatives of patients who have subarachnoid hemorrhage from ruptured intracranial aneurysms are themselves at risk for subarachnoid hemorrhage. We studied the benefits and risks of screening for aneurysms in the first-degree relatives of patients with sporadic subarachnoid hemorrhage. Methods: We screened 626 first-degree relatives (parents, siblings, or children) of 160 patients with sporadic subarachnoid hemorrhage, from a prospective series of 193 consecutive index patients. Magnetic resonance angiography was the screening tool, and conventional angiography was used as the reference test in subjects thought to have aneurysms. Six months after elective operation, outcome was assessed by means of the modified Rankin scale of neurologic function. This observational study design was combined with a decision-analysis model to estimate the effectiveness of screening. The efficiency of screening was defined by the number of relatives who needed to be screened in order to prevent one subarachnoid hemorrhage. Results: Aneurysms were found in 25 of 626 first-degree relatives (4.0 percent; 95 percent confidence interval, 2.6 to 5.8 percent). Eighteen underwent surgery, which resulted in a decrease in function in 11 (disabling in 1). Five had medium-sized aneurysms that were 5 to 11 mm in diameter, 11 had small aneurysms that were less than 5 mm, and 2 had both small and medium-sized aneurysms. On average, surgery increased estimated life expectancy by 2.5 years for these 18 subjects (or by 0.9 month per person screened), at the expense of 19 years of decreased function per person. The number of relatives who would need to be screened in order to prevent 1 subarachnoid hemorrhage on a lifetime basis was 149, and 298 would have to be screened in order to prevent 1 fatal subarachnoid hemorrhage. Conclusions: Implementation of a screening program for the first-degree relatives of patients with sporadic subarachnoid hemorrhage does not seem warranted at this time, since the resulting slight increase in life expectancy does not offset the risk of postoperative sequelae.
James K. Liu and William T. Couldwell
Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.
Spencer Twitchell, Hussam Abou-Al-Shaar, Jared Reese, Michael Karsy, Ilyas M. Eli, Jian Guan, Philipp Taussky, and William T. Couldwell
patients with pituitary tumors. 7 The advancement of interventional techniques in the management of intracranial aneurysms and the results of the International Subarachnoid Hemorrhage Trial have convinced many neurosurgeons to switch their management strategy from the surgical to the endovascular route. 15 However, the costs of surgical versus endovascular intervention as well as the cost-effectiveness of these two approaches have been an area of debate since the late 1990s, with various studies showing contradictory results. In addition, the increased use of flow
Paul A. House and William T. Couldwell
Fenestration of the optic nerve or chiasm due to the presence of an aneurysmal dilation of the internal carotid artery (ICA) has been described previously. In three of five cases reviewed recently, the optic nerve was penetrated by an ICA—ophthalmic artery aneurysm. 3 Penetration of the optic nerve was due to a ruptured anterior communicating artery aneurysm or an aneurysm of the anterior wall of the ICA in the other cases published to date. 2, 4 Splitting of the optic nerve without the presence of a penetrating aneurysm has not been identified previously
Giant fusiform aneurysm in an adolescent with PHACES syndrome treated with a high-flow external carotid artery–M3 bypass
Case report and review of the literature
Peter Kan, James K. Liu, and William T. Couldwell
, however, concomitant intracranial arterial dysplasia and giant aneurysms have not been reported in patients with PHACES syndrome. In this article, we report a unique case of an adolescent boy with an incomplete phenotypic expression of PHACES syndrome who also harbored right hemispheric arterial dysplasia and a giant fusiform ICA aneurysm ipsilateral to the side of the facial hemangioma. The patient was successfully treated with a high-flow interpositional SVG bypass from the ECA to the M 3 segment, followed by proximal ICA occlusion that resulted in flow reversal
Al-Wala Awad, Craig Kilburg, Michael Karsy, William T. Couldwell, and Philipp Taussky
F low diversion with the Pipeline embolization device (PED) has been shown to be safe and effective for treatment of internal carotid artery (ICA) aneurysms occurring from the petrous to the communicating segment and is quickly becoming the standard of care for the treatment of these aneurysms. 1 , 2 Despite the widely accepted use of flow diversion, questions remain regarding the main mechanism by which aneurysm occlusion occurs. It is possible that the flow-diverting qualities of the device result in clot formation within the aneurysm and finally occlusion of
Mandy Binning, Bradley Duhon, and William T. Couldwell
This 7-year-old previously healthy girl presented with right hemiparesis related to an embolic stroke from a thrombosed lateral lenticulostriate aneurysm. Initial CT scanning demonstrated a density along the M 1 segment of the left middle cerebral artery (MCA) consistent with thrombus but no extraluminal hemorrhage. Magnetic resonance imaging subsequently revealed an acute left basal ganglia infarct and an apparent 1-cm aneurysm of the M 1 segment of the left MCA. Conventional cerebral angiography demonstrated filling of only 4 mm of this fusiform aneurysm