Gerard M. Debrun

Selection of cerebral aneurysms for treatment using Guglielmi detachable coils: the preliminary University of Illinois at Chicago experience.

OBJECTIVE We present our initial experience with Guglielmi detachable coils (GDCs). The aim of this study was to determine the criteria for aneurysms, ruptured or unruptured, that are suitable for this technique. The importance of aneurysm geometry and its impact on the final results are discussed. METHODS A retrospective analysis of 329 patients with 339 cerebral aneurysms that were treated at the University of Illinois Hospital at Chicago from May 1994 to June 1997 was conducted. One hundred eighty-five patients were treated surgically, and 144 were selected for treatment using GDCs. Of the 144 patients selected for GDC treatment, 55 patients with 55 aneurysms were admitted during the acute phase of subarachnoid hemorrhage and 89 patients with 97 aneurysms had nonruptured aneurysms or were treated after clinical recovery of previously ruptured aneurysms. All procedures were performed with the patients under general anesthesia and with systemic heparinization using live simultaneous biplane roadmapping, with the exception of the first four patients. These patients were treated before the installation of the biplane system. The percentage of aneurysm occlusion was determined at the end of each procedure. Follow-up angiography was scheduled to be performed at 6 months, 1 year, and 2 years after treatment. PATIENT SELECTION For the initial 25 patients (Group 1), selection for coiling was restricted to nonsurgical candidates or patients in whom coiling was thought to be the best treatment choice, based on medical condition and location of the aneurysm. The geometry of the aneurysm was not considered to be an important factor in the selection for coiling. The remaining patients (Group 2) were selected for coiling based on aneurysm geometry, as determined by pretherapeutic angiography. Aneurysms that were considered to be favorable for coiling included those that had a dome-to-neck ratio of at least 2 and an absolute neck diameter less than 5 mm. RESULTS The initial 25 patients (Group 1) were treated from May 1994 to February 1995. There were high morbidity and mortality rates, with 56% of the treated aneurysms occluded at 6 months. The remaining patients (Group 2) consisted of 119 patients with 123 aneurysms. There was no mortality directly related to the coiling procedure, and permanent morbidity was limited to 1.0%. Three patients (2.5%) developed transient neurological deficits secondary to the procedure, and seven patients (5.8%) experienced periprocedural complications that did not result in neurological sequelae. The morphological results were strongly correlated to the geometry of the aneurysms, with a complete occlusion rate of 72% among the acutely ruptured aneurysms and 80% among the nonacute aneurysms, when patients were selected for treatment based on the geometry of the aneurysms and the dome-to-neck ratio was at least 2. The occlusion rate dropped to 53% when selection was not based on aneurysm geometry and the dome-to-neck ratio was less than 2. A summary of the morphological outcomes for the Group 2 patients shows that 86% of the aneurysms that initially underwent coiling using GDCs were completely occluded (78% by coils alone, 3.0% in conjunction with surgery, and 5.0% with parent artery occlusion). Residual small neck remnants were present in 11% of the Group 2 aneurysms (3.0% were scheduled for surgical treatment of residual neck remnant growths not amenable to further endovascular treatment, and 8% were scheduled for initial 6-mo follow-up examinations). Death resulting from unrelated causes before initial follow-up occurred in 3.0% of the patients. CONCLUSION These preliminary results suggest that using GDCs is a safe technique resulting in low morbidity and mortality rates for the treatment of intracranial aneurysms in appropriately selected patients. The percentage of complete aneurysm occlusion is related to the density of coil packing, which is strongly dependent on the geometry of the aneurysm. Optim

Embolization of the Nidus of Brain Arteriovenous Malformations withn-Butyl Cyanoacrylate

OBJECTIVE To demonstrate that nidus embolization of brain arteriovenous malformations (AVMs) with Histoacryl (B. Braun, Melsungen, Germany) is effective and yields low morbidity and mortality rates. METHODS We present a retrospective analysis of 54 brain AVMs treated at the University of Illinois at Chicago from April 1994 to December 1995. Treatment modalities included embolization in all cases and then surgical resection or radiosurgery. INSTRUMENTATION The nidus was reached with the combined use of a Magic microcatheter (Balt, Montmorency, France) and a Terumo 0.010-inch guidewire. TECHNIQUE Embolization was performed only when the tip of the microcatheter was wedged into the nidus of the AVMs with no reflux of contrast proximally. The embolization was performed using simultaneous biplane roadmapping with the patient under general anesthesia without Amytal testing. RESULTS Twenty-six of 54 patients are still waiting for more radical treatment. Two deaths and two minor and one severe permanent neurological deficit occurred. Three patients were cured with embolization alone; 11 patients were cured after surgical resection. Three patients underwent radiosurgery, with one cure after 1 year. CONCLUSION Nidus embolization with Histoacryl is an effective technique that permits complete cure of a large number of brain AVMs, with or without surgical resection and/or radiosurgery.

Follow-up angiography of intracranial aneurysms treated with endovascular placement of Guglielmi detachable coils.

OBJECTIVE The success of endovascular treatment of intracranial aneurysms with Guglielmi detachable coils (GDCs) is dependent on the long-term exclusion of the aneurysm from the circulation. We reviewed our experience with the long-term angiographic follow-up monitoring of aneurysms that had been treated with GDCs. METHODS All patients whose aneurysms had been treated with GDCs between January 1995 and August 1999 and who subsequently underwent follow-up angiography at 6 months or more were included in this study. We reviewed all of the angiographic findings, to determine the percentage of aneurysm occlusion on the initial angiograms and on the last available follow-up angiograms. The categories of aneurysm occlusion used were 100%, ≥95%, and less than 95% occlusion. RESULTS One hundred thirty patients with 141 aneurysms underwent 143 endovascular coiling procedures and subsequently underwent angiographic follow-up monitoring of 6 months or more. There were 102 female and 28 male patients. The mean angiographic follow-up period was 16.7 months (range, 6–62 mo). The initial rates of occlusion were 100% for 56 aneurysms (39%), ≥95% for 65 aneurysms (46%), and less than 95% for 22 aneurysms (15%). Recurrence of one aneurysm (1.8%) was observed. Of the 87 aneurysms that were incompletely occluded initially, there was progressive thrombosis in 40 (46%), stable neck remnants in 23 (26%), and enlargement of the residual neck in 24 (28%). The final occlusion rates, determined on the last available angiograms, were 100% for 88 aneurysms (61%), ≥95% for 31 aneurysms (22%), and less than 95% for 24 aneurysms (17%). No patient experienced repeat or new subarachnoid hemorrhage more than 6 months after the initial treatment. CONCLUSION Late angiographic follow-up monitoring of aneurysms that have been treated with GDCs demonstrates the durability of the treatment. Aneurysms with large residual neck remnants were subjected to further treatment, whereas aneurysms with small residual neck remnants remain under observation.

What percentage of surgically clipped intracranial aneurysms have residual necks

OBJECTIVE To determine the angiographically proven rate and persistence of occlusion of intracranial aneurysms after surgical clipping as reported in the literature. This should establish a basis for comparing surgery with new endovascular methods of treatment. METHODS We reviewed the literature published during the period from 1979 through 1999, dividing the articles into two groups. The first group of articles reported patients undergoing surgical treatment with immediate postoperative angiography. The second group of articles documented symptomatic recurrence or regrowth of aneurysms that were surgically treated previously. The data from these articles are presented for analysis. RESULTS During the period 1979 to 1999, six series of patients undergoing surgical treatment of aneurysms with immediate postoperative angiography were reported. These reported series comprised a total of 1,397 patients, of whom 1,370 underwent postoperative angiography demonstrating 1,569 clipped aneurysms. Residual filling was found in 82 aneurysms (5.2%) on postoperative angiography. Of the 1,370 patients, only 124 patients with 169 aneurysms were reported to have had any long-term angiographic follow-up. The second group consisted of 226 patients representing six reported groups of patients, who either presented up to 24 years after aneurysm clipping with recurrent symptoms of hemorrhage or mass effect, or had important findings on intraoperative and postoperative angiograms. CONCLUSION The lack of information regarding both the frequency of residual filling or regrowth and long-term angiographic follow-up of patients with surgically treated aneurysms makes meaningful comparison between surgical treatments and new treatment methods for intracranial aneurysms difficult or impossible. Detailed analysis with high-quality angiography should be performed to determine the success of surgical treatment.

Surgery following endovascular coiling of intracranial aneurysms

BACKGROUND Surgery for intracranial aneurysms that have been treated by endovascular coiling is a new challenge for neurosurgeons and the need for it will undoubtedly continue to increase. The indications for, timing, and technique of surgery in our experience are described. METHODS We have reviewed our experience with 11 patients who underwent surgery following endovascular coiling with Guglielmi detachable coils (GDCs) of an aneurysm. We analyzed the indications for surgery, surgical techniques used, and patient outcome. RESULTS There were nine female and two male patients. The mean age was 49 years (range 13 to 67 years). The intervals between coiling and surgery were 1, 2, 3, 4, 7, 7, 10, and 14 days, 6 weeks, 2, 18, and 25 months. The indications for surgery were partial treatment (3), growth of residual neck (2), persistent mass effect of a giant aneurysm (1), mass effect from the coil ball (2), coil migration (2), and coil protrusion with embolic event (1). The coils were removed at the time of surgery from 9 of 11 aneurysms before clipping. In two cases it was possible to place a clip across the neck of the aneurysm without removing the coils, as the coils no longer occupied the neck. There were two permanent deficits directly related to the endovascular procedures. Two other patients who presented with subarachnoid hemorrhage had residual neurological deficits post surgery and one patient with a giant aneurysm had persistent visual loss. CONCLUSION Surgery remains a viable option at any time for treating aneurysms that have been previously treated by GDC placement. The operative approach is determined by the need for coil removal and the duration since coiling.

Endovascular treatment of paraclinoid aneurysms

BACKGROUND Paraclinoid aneurysms include those that are distal to the cavernous segment of the internal carotid artery and proximal to the posterior communicating artery. The purpose of this study was to review our experience with the endovascular treatment of this group of aneurysms, which are difficult to treat surgically. METHODS Between June 1994 and April 1999, 66 patients (56 female, 10 male) with a mean age of 50.1 years (range 13-75, median 51) underwent endovascular treatment for 71 paraclinoid aneurysms. The mean size of the dome was 8.9 mm (range 3-25 mm, median 7) and the of neck was 3.8 mm (range 1.4-8 mm, median 4). Thirteen patients presented with acute subarachnoid hemorrhage, and 4 with previous subarachnoid hemorrhage. Six aneurysms produced mass effect with visual symptoms, 4 presented with transient ischemic attacks, and 44 were incidental. Nine patients had had previous unsuccessful surgery. All procedures were performed under general anesthesia and with systemic heparinization. RESULTS Ninety endovascular procedures were performed on 71 aneurysms: GDC coiling in 78 (including 45 with the remodeling technique), permanent balloon occlusion in 9, and 3 had both GDC coiling and permanent balloon occlusion. In ten aneurysms it was not possible to place coils in the lumen of the aneurysm with the available technology and balloon occlusion was not indicated. Five of these were treated surgically and 5 remain untreated. All patients had immediate post procedure angiography. Of the 61 aneurysms that were treated, 46 (75%) have angiographic follow-up of 6 months or more. Morphological outcome following endovascular therapy for 61 aneurysms at last available follow-up showed > 95% occlusion in 52/61 (85.2%) and <95% in 9/61 (14.8%). Eight patients required surgery, 2 for partial coiling, 2 for refilling of a neck remnant, 2 for persistent mass effect and 2 for coil protrusion. In the 90 procedures performed, 2 (2.2%) patients had major permanent deficits (1 monocular blindness, 1 hemiparesis), 1 (1.1%) had a minor visual field cut, and 2 (2.2%) patients died from major embolic events. CONCLUSION Properly selected paraclinoid aneurysms can be successfully treated by endovascular technology. The morbidity and mortality rate of the endovascular approach in our experience is equal to or better than the published surgical series of similar aneurysms. We recommend that the endovascular approach be given primary consideration in the treatment of paraclinoid aneurysms.

Contemporary management of subarachnoid hemorrhage and vasospasm: the UIC experience

BACKGROUND Cerebral vasospasm is a well-known and serious complication of aneurysmal subarachnoid hemorrhage. The means of monitoring and treatment of vasospasm have been widely studied. Each neurosurgical center develops a protocol based on their experience, availability of equipment and personnel, and cost, so as to keep morbidity and mortality rates as low as possible for their patients with vasospasm. METHODS At the University of Illinois at Chicago, we have developed algorithms for the diagnosis and management of cerebral vasospasm based on the experience of the senior authors over the past 25 years. This paper describes in detail our approach to diagnosis and treatment of aneurysmal subarachnoid hemorrhage and vasospasm. Our discussion is highlighted with data from a retrospective analysis of 324 aneurysm patients. RESULTS Over 3 years, 324 aneurysms were treated; 185 (57%) were clipped, 139 (43%) were coiled. The rate of vasospasm for the 324 patients was 27%. The rate of hydrocephalus was 32% for those patients who underwent clipping, and 29% for those coiled. The immediate outcomes for those who underwent clipping was excellent in 35%, good in 38%, poor in 15.5%, vegetative in 3%, and death in 8% of the patients. For those who underwent coiling the immediate outcome was excellent in 64%, good in 14.5%, vegetative in 2.5%, and death in 14.5% of the patients. These statistics include all Hunt and Hess grades. For those patients who underwent clipping, 51% were intact at 6 months follow-up, 15% had a permanent deficit, 10% had a focal cranial nerve deficit, and 2% had died from complications not directly related to the procedure. For those patients who had undergone coiling, 75% were intact at 6 months follow-up, 12.5% had a permanent deficit, and 12.5% had a cranial nerve deficit, with no deaths. CONCLUSIONS The morbidity and mortality of cerebral vasospasm is significant. A good outcome after aneurysmal subarachnoid hemorrhage is dependent upon careful patient management in the preoperative, perioperative, and postoperative periods. The timely work-up and aggressive treatment of neurological deterioration, whether or not it is because of vasospasm, is paramount.

Hemodynamic Evaluation of Basilar and Vertebral Artery Angioplasty

OBJECTIVE The postangioplasty evaluation of a stenotic vessel is often conducted by studying serial angiograms to determine the anatomic reduction in stenosis. In flow-limiting stenosis, the hemodynamic change that accompanies these anatomic changes is of great importance in evaluating the success of the angioplasty. The purpose of this article is to demonstrate the usefulness of phase contrast magnetic resonance angiography (PCMRA) in evaluating the hemodynamic changes that occur after angioplasty of the basilar and vertebral arteries. METHODS Between January 1998 and February 2000, PCMRA was performed for the hemodynamic evaluation of 130 patients who presented at our institution. Twenty-six patients were evaluated for vertebrobasilar insufficiency, and flow rates of their vertebral and basilar arteries were determined. In five patients, angioplasty was done on the basilar or vertebral arteries, and PCMRA was performed to determine flow rates before and after the procedure. RESULTS Of the five patients undergoing angioplasty, the average percentage of stenosis was 81%. The average increase in basilar artery flow rate was 46 ml/min (P < 0.05) after angioplasty. Two of these patients are described. One patient demonstrated the comparison of flow rates in the vertebral and basilar arteries after angioplasty. The second patient showed follow-up flow rates measured after angioplasty and up to 4 months later to predict restenosis. CONCLUSION The use of flow rate data before and after angioplasty is helpful not only to evaluate the treatment immediately after the procedure but also to evaluate the effectiveness of the treatment during a long period. PCMRA provides a noninvasive method for measuring arterial flow rates with far-reaching implications in neurosurgery.

Three cases of spontaneous direct carotid cavernous fistulas associated with Ehlers-Danlos syndrome type IV

We are reporting three cases of spontaneous direct carotid cavernous fistulas (CCFs) associated with Ehlers-Danlos syndrome (EDS) out of a series of 147 direct CCFs. The internal carotid artery could be preserved in only one case. Two patients had severe bilateral irregularities of caliber of both internal carotid arteries. Two patients had recurrence of their symptoms after a first balloon was detached in the cavernous sinus (CS) necessitating a second treatment. Two patients died several months later from complications associated with their disease. The treatment of direct CCFs associated with Ehlers-Danlos syndrome is more difficult and more risky than most direct CCFs. The permanent occlusion of the ICA, which may be difficult to avoid, increases the risks of development of aneurysm on the contralateral side.

Angiographic workup of a carotid cavernous sinus fistula (CCF) or what information does the interventionalist need for treatment

It is rare that a patient with a carotid cavernous sinus fistula (CCF) is referred to the interventionalist with a good and exhaustive angiographic workup, providing all the information necessary for a therapeutic decision. The goal of this technical note is to refresh our memory on the best way to study this group of patients. It does not have the pretension to bring a new technique. As there are two types of CCFs, direct and indirect, there are also two different angiographic workups.