Management-related morbidity in unselected aneurysms of the upper basilar artery

Should we still consider clips for basilar apex aneurysms? A critical appraisal of the literature

Background:

Basilar apex aneurysms constitute 5–8% of all intracranial aneurysms, and their treatment remains challenging for both microsurgical and endovascular approaches. The perceived drawback of the microsurgical approach is its invasiveness leading to increased surgical morbidity. However, many high-volume centers have shown excellent clinical results with better occlusion rates compared to endovascular treatment. With endovascular therapy taking a larger role in the management of cerebral aneurysms, the future role of microsurgery for basilar apex aneurysm treatment is unclear.

Methods:

We performed a literature search to review the microsurgical and endovascular outcomes for basilar apex aneurysms.

Results:

Many studies have examined the efficacy of microsurgical and endovascular treatment for intracranial aneurysms, including large randomized trials such as ISAT and BRAT, prospective observational series such as ISUIA, and many single-center retrospective reviews. The recruitment number for posterior circulation aneurysms, specifically for basilar apex aneurysms, was limited in most prospective trials, thus failing to offer clear guidance on basilar apex aneurysm treatment. Recent single-center series report good clinical outcomes between 57–92% for surgical series and 73–96% in endovascular series. The durability of aneurysm occlusion remains superior in surgical cases. The techniques and devices in endovascular treatment have improved treatment aneurysm occlusion rates but more follow-up is needed to confirm long-term durability.

Conclusions:

Both microsurgical and endovascular approaches should be complementing each other to treat basilar apex aneurysms. Although endovascular therapy has taken a larger role in the treatment of basilar apex aneurysms, many indications still exist for the use of microsurgery. Advancements in microsurgical techniques and good case selection will allow for acceptably low morbidity after surgical treatment while maintaining its superior durability.

Mobilization of the transcavernous oculomotor nerve during basilar aneurysm surgery: biomechanical bases for better outcome

BACKGROUND

The transcavernous approach adds a significant exposure advantage in basilar aneurysm surgery. However, one of its frequently reported side effects is postoperative oculomotor nerve palsy.

OBJECTIVE

To present the technique of mobilizing the oculomotor nerve throughout its intracranial course and to analyze its consequences on the nerve tension and clinical outcome.

METHODS

The oculomotor nerve is mobilized from its mesencephalic origin to the superior orbital fissure. Its degree of mobility, related to the imposed pulling force, was measured in 11 cadaveric nerves. Tension was mathematically deduced and compared before and after mobilizing of the cavernous segment. One hundred four patients treated for basilar aneurysms with the orbitozygomatic pretemporal transcavernous approach were followed up for a 1-year period and evaluated for postoperative oculomotor nerve palsy.

RESULTS

Releasing the transcavernous segment compared to cisternal mobilization alone resulted in a significant increase in freedom of mobility from 4 to 7.9 mm (P < .001) and in a significant decrease in tension from 0.8 to 0.5 N (P = .006). Ninety-nine percent of aneurysms treated with this technique were amenable to neck clipping, and a total of 84% of patients had a good postoperative outcome (modified Rankin Scale score, 0-2). All patients showed direct postoperative palsy; however, 97% had a complete recovery by 9 months. Only 3 patients had a persistent diplopia on medial gaze, which was corrected with prism glasses.

CONCLUSION

Mobilization of the transcavernous oculomotor nerve results in better maneuverability and less tension on the nerve, which lead to successful surgical treatment and favorable oculomotor outcome.

Factors Predicting the Oculomotor Nerve Palsy following Surgical Clipping of Distal Vertebrobasilar Aneurysms: A Single-Institution Experience

Background The aim of our study was to identify various clinical and radiologic factors that correlate with the oculomotor nerve palsy following clipping of distal vertebrobasilar aneurysms. Methods A total of 48 patients with 51 aneurysms were included in this retrospective study . Patient's age, gender, size, location, and projection of the aneurysm, preoperative Hunt and Hess (H&H) grade, presence of subarachnoid hemorrhage (SAH), temporary clipping, preoperative third nerve palsy, and Glasgow Outcome Scale were included in the model for analysis. Results A total of 15 patients (31.25%) developed oculomotor nerve palsy following clipping of basilar apex aneurysms. 38 patients (79.2%) presented with SAH and 35 patients (72.9%) had poor H&H grades at presentation. The size of the aneurysm (p = 0.03), preoperative H&H grade (p = 0.04), preoperative oculomotor nerve dysfunction (p = 0.007), and projection of an aneurysm (p = 0.004) had shown a significant correlation with the oculomotor nerve palsy. The size of the aneurysm (p = 0.030, odds ratio: 0.381; 95% confidence interval, 0.175-0.827] was an independent predictor of postoperative nerve dysfunction. Conclusion The size of the aneurysm, clinical grade at presentation, and projection of the aneurysm correlated with the oculomotor nerve dysfunction following clipping. These clinical and radiologic parameters can be used to predict the oculomotor nerve outcome.

Endovascular Treatment of Basilar Trunk Saccular Aneurysms

Basilar artery (BA) trunk aneurysms are rare and still remain a formidable surgical challenge. The purpose of this retrospective study was to report the clinical entities and results of endovascular surgery of BA trunk saccular aneurysms. Between 1995 and 2009, 14 patients with 14 BA trunk saccular aneurysms underwent endovascular surgery. Six patients presented subarachnoid hemorrhage (SAH), three patients had another associated aneurysm which developed SAH, one patient presented with mass effect to the brain stem, and four patients were incidentally discovered. Five ruptured and seven unruptured aneurysms were successfully treated by endovascular surgery. Another one incompletely embolized aneurysm had grown to huge size five years later and the patient underwent a Hunterian ligation with a radial artery graft between the extracranial vertebral artery and the posterior cerebral artery. In one ruptured case, we attempted neck clipping, but this was abandoned because of concern for neck tearing by clipping. The aneurysm was embolized using detachable coils later. BA trunk aneurysms showed characteristic features such as so-called lateral aneurysm (43%), multiple aneurysms (43%) and four BA fenestrations (36%). The unusual high incidence of associated various vascular anomalies suggests that focal wall weakness must be based on the mechanism of aneurysm initiation on the BA trunk. Most patients presented with SAH. Pre-treatment neurological state was predictive for clinical outcome. Endovascular surgery is an effective therapeutic alternative that is associated with low morbidity and mortality rates, and should be considered the first choice treatment.

Endovascular treatment of aneurysms arising from the basilar artery trunk and branches

This study reports our experience with the endovascular treatment of basilar artery (BA) trunk and branch aneurysms. Subjects included 16 patients with BA trunk and branch aneurysms who underwent endovascular treatment in our hospital from October 2000 to October 2009, including four patients with associated arteriovenous malformation (AVM), two with associated moyamoya disease, one with multiple aneurysms at adjacent sites, and one with a distant aneurysm. Endovascular coil embolization, together with stent or balloon assistance when necessary, or while occluding the parent artery was performed. Associated diseases were managed intraoperatively or in the second stage, or treated with gamma knife radiotherapy, or followed up. Two patients with unsuccessful embolization died of re-rupture at the fourth month and fifth month follow-up. The remaining 14 patients reported good outcomes and experienced no re-rupture of either the aneurysm or associated disease. Angiographic follow-ups were conducted for the 14 patients for six to 12 months. Digital subtraction angiography (DSA) examination at the last follow-up showed no recurrence of the BA trunk and branch aneurysms. Together, BA trunk and branch aneurysms should be actively managed via endovascular techniques to prevent serious consequences due to aneurysm rupture and bleeding. Favorable outcomes can be obtained by the proper selection of endovascular treatment regimens.

Giant vertebrobasilar aneurysm treated with bilateral vertebral artery occlusion. Two case reports

Giant vertebrobasilar aneurysms constitute a relatively uncommon subgroup of aneurysms with a high mortality rate. These aneurysms are often difficult to treat with conventional clipping or coiling because of their location and their morphology. Here we describe two patients with giant vertebrobasilar aneurysms, both of which were successfully treated with bilateral vertebral artery occlusion. This approach is suggested as a definitive treatment for vertebrobasilar aneurysms in appropriate circumstances.

Results of endovascular management for mid-basilar artery aneurysms

We evaluated the results of endovascular management of patients with mid-basilar artery aneurysm (mBAA). During a seven year period, 14 patients (mean age 39.6 years, male/female ratio 1:1) with mBAA were treated with endovascular techniques at our institute. Pretreatment clinical grades were determined using the Hunt-Hess scale. Outcome was evaluated using the Glasgow Outcome Scale scores (GOS) during a mean follow-up period of 15.6 months (range, three to 70 months). Fourteen patients with 15 mBAAs were treated endovascularly. Four (28.6%) patients died of rebleeding within one day after embolization. In ten mBAAs, immediate postprocedural angiograms showed that complete occlusion was achieved, subtotal occlusion in one, and incomplete occlusion in four. Follow-up angiographic results in ten patients confirmed complete occlusion of 11 aneurysms. Long-term outcome was good (GOS Score 4 or 5) in ten patients (71.4%) and fatal (GOS Score 1) in four (28.6%). Favorable overall long-term outcome can be achieved in 78.6% patients with mBAAs. Endovascular management of mBAAs is an effective treatment in the long-term. In our experience, the natural history of mBAAs is dismal.

Clinical outcomes of basilar artery aneurysms

To evaluate the effects of endovascular treatments, we retrospectively analyzed a consecutive series of patients with basilar artery aneurysms (BAAs) treated endovascularly. During a seven year period, 43 patients (mean age 42.2 years, male/female ratio 21:22) with BAAs were treated mainly with endovascular techniques at Beijing Tiantan Hospital. Pretreatment clinical grades were determined using the Hunt-Hess scale. Outcome was evaluated using the Glasgow Outcome Scale scores (GOS) during a mean follow-up period of 21.1 months (range, 1 to 72 months). Forty-three patients had 44 BAAs, one MCA aneurysm and one P1 aneurysm. Endovascular treatment was technically feasible in 40 patients. One aneurysm thrombosed spontaneously after initial angiography. Four (9.3%) patients died periprocedurally. Immediate postprocedural angiograms in 44 BAAs showed that complete occlusion was achieved in 33 BAAs, subtotal occlusion in one and incomplete occlusion in seven. Follow-up angiographic results in 30 patients confirmed complete occlusion of 27 aneurysms, subtotal occlusion in one, and incomplete occlusion in two. Two patients with vertebrobasilar atheromatous fusiform aneurysms were treated with antiplatelet medications. Long-term outcome was good (GOS Score 4 or 5) in 39 patients (90.7%) and fatal (GOS Score 1) in four (9.3%). Favorable overall long-term outcome can be achieved in patients with BA apex aneurysms, and in 78.6% of those with BA trunk aneurysms when using endovascular techniques. Endovascular coil embolization of BAAs is an effective treatment in the long-term. Patients with vertebrobasilar atheromatous fusiform aneurysms can be treated with antiplatelet medications.

Management of postoperative arterial hemorrhage after pancreato-biliary surgery according to the site of bleeding: re-laparotomy or interventional radiology

BACKGROUND/PURPOSE

Intra-abdominal arterial hemorrhage is still one of the most serious complications after pancreato-biliary surgery. We retrospectively analyzed our experiences with 15 patients in order to establish a therapeutic strategy for postoperative arterial hemorrhage following pancreato-biliary surgery.

METHODS

Between August 1981 and November 2007, 15 patients developed massive intra-abdominal arterial bleeding after pancreato-biliary surgery. The initial surgery of these 15 patients were pylorus-preserving pancreatoduodenectomy (PPPD) (7 patients), hemihepatectomy and caudate lobectomy with extrahepatic bile duct resection or PPPD (4 patients), Whipple's pancreatoduodenectomy (PD) (3 patients), and total pancreatectomy (1 patient). Twelve patients were managed by transcatheter arterial embolization and three patients underwent re-laparotomy.

RESULTS

Patients were divided into two groups according to the site of bleeding: SMA group, superior mesenteric artery (4 patients); HA group, stump of gastroduodenal artery, right hepatic artery, common hepatic artery, or proper hepatic artery (11 patients). In the SMA group, re-laparotomy and coil embolization for pseudoaneurysm were performed in three and one patients, respectively, but none of the patients survived. In the HA group, all 11 patients were managed by transcatheter arterial embolization. None of four patients who had major hepatectomy with extrahepatic bile duct resection survived. Six of seven patients (85.7%) who had pancreatectomy survived, although hepatic infarction occurred in four.

CONCLUSIONS

Management of postoperative arterial hemorrhage after pancreato-biliary surgery should be done according to the site of bleeding and the initial operative procedure. Careful consideration is required for indication of interventional radiology for bleeding from SMA after pancreatectomy and hepatic artery after major hepatectomy with bilioenteric anastomosis.

Plical resection in pre-temporal approach for basilar bifurcation aneurysms: preliminary surgical experience and cadaveric study

OBJECT

Although a pre-temporal approach (PA) can provide a wide space for preservation of thalamoperforating atrteries in direct surgery for basilar bifurcation aneurysms (BBAs), it cannot always secure adequate proximal control. The authors described the advantages of plical resection added to PA for BBAs.

METHODS

Between October 1998 and April 2000, eight consecutive patients with BBAs were treated in the neurosurgical department of Kurashiki Central Hospital. Among them, five patients received direct clipping using this method. There were four females and one male, ages ranging from 61 to 77 (mean 70.8 years). Mean aneurysmal size and distance between the in"terclinoidal line and the aneurysmal neck was 4.5 and 9.5 mm, respectively. The operative procedures consisted of the following components; 1) fronto-temporal craniotomy with translocation of orbito-zygomatico-malar bone for PA, 2) preservation of lateral branches of the superficial sylvian veins, 3) resection of plica dural folds to increase the operative field up to the oculomotor nerve (OMN).

RESULTS

Complete clipping was achieved without thalamic infarction or temporal contusion in all patients. Three of the five patients suffered from transient right OMN palsy which recovered within two months after surgery.

CONCLUSION

Plical resection in the pre-temporal approach might be beneficial in the surgical treatment of BBAs when proximal control seems difficult.

RESULTS OF MICROSURGICAL CLIPPING OF 50 HIGH COMPLEXITY BASILARAPEX ANEURYSMS

OBJECTIVE

Complex basilar aneurysms (large size, wide base, low bifurcation, and dysmorphic posteriorly projecting domes) frequently fail endovascular treatment. We report our experience using the pretemporal transzygomatic transcavernous approach with 50 complex basilar aneurysms.

METHODS

Using the pretemporal transcavernous route, opening the occulomotor trigone, and removing the anterior clinoid and the posterior clinoid when necessary, a wide exposure of the interpeduncular fossa is achieved. Temporary clips are applied to a perforator-free zone of the basilar trunk, proximal to the superior cerebellar artery. Complexity criteria in the 50 aneurysms included large or giant size in 27 patients, wide dysmorphic base in 18 patients, low bifurcation in 21 patients, posteriorly projecting dome in 11 patients, and dolichoectasia of the apex in three patients.

RESULTS

Twenty-five patients presented with subarachnoid hemorrhage. There were 14 men and 36 women between the ages of 32 and 76 years (mean, 52.2 yr). Forty-nine aneurysms (98%) were successfully clipped. There was no procedure-related mortality. Two patients died (one from delayed bowel ischemia and one from a vasospasm-related complication). There were three ischemia-related events, two of which were procedure-related (medial thalamic lacunar infarct, superior cerebellar distribution ischemia) and one which was a third distal middle cerebral cardiac embolus after stopping Coumadin (DuPont Pharmaceuticals, Wilmington, DE) for atrial fibrillation. Transient partial or complete occulomotor palsies occurred in all patients with full recovery as the rule, except in one patient. At discharge, Glascow Outcome Scale scores were 4 or 5 in 88% of the patients. At the 6-month follow-up examination, Rankin Outcome Scale scores were 0 to 2 in 92% of the patients.

CONCLUSION

Our experience reintroduces microsurgery as a safe and more durable treatment option for the management of complex basilar apex aneurysms that tend to have a higher rate of failure with endovascular therapy.

Evaluation of the Stability of Small Ruptured Aneurysms with a Small Neck after Embolization with Guglielmi Detachable Coils. Correlation between Coil Packing Ratio and Coil Compaction

SUMMARY

It is difficult to predict the compaction of Guglielmi detachable coils (GDC) after endovascular surgery for aneurysms. Therefore, we studied the relationship between the coil packing ratio and compaction in 62 patients with acute ruptured intracranial aneurysms that were small (< 10 mm) had a small neck (< 4 mm) and were coil-embolized with GDC-10. We recorded the maximum prospective coil length, L, as the length that correspond with the volume of packed coils occupying 30% of the aneurysmal volume. L was calculated as L (cm) = 0.3 x a x b x c and the coil packing ratio expressed as packed coil length/L x 100, where a, b, and c are the aneurysmal height, length, and width in mm, respectively. Angiographic followup studies were performed at three months and one and two years after endovascular surgery. Of the 62 patients, 16 (25.8%) manifested angiographic coil compaction (ten minor and six major compactions); the mean coil packing ratio was 51.9 +/- 13.4%. The mean coil packing ratio in the other 46 patients was 80.5 +/- 20.2% and the difference was statistically significant (p < 0.01). In all six patients with major compaction the mean packing ratio was below 50%. We detected 93.8% of the compactions within 24 months of coil placement. In patients with small, necked aneurysms, the optimal coil packing ratio could be identified with the formula 0.3 x a x b x c. The probability of compaction was significantly higher when the coil packing ratio was under 50%. To detect coil compaction post-embolization, follow-up angiograms must be examined regularly for at least 24 months.

Surgical Clipping of Complex Basilar Apex Aneurysms: A Strategy for Successful Outcome Using the Pretemporal Transzygomatic Transcavernous Approach

OBJECTIVE:

Complex basilar apex aneurysms (large size, wide and complex neck, tortuous parent vessels) continue to pose a challenge in treatment. Endovascular treatment has a high risk of recanalization, and surgical treatment is limited by the space and time necessary to achieve safe clipping. To overcome these obstacles, a modification of previously reported approaches was developed. The pretemporal transzygomatic transcavernous approach and a clipping strategy were used in the treatment of 21 high-complexity basilar apex aneurysms.

METHODS:

By use of the pretemporal route, the zygomatic notch was widened, the anterior clinoid was removed, the cavernous sinus was partially exposed, and the oculomotor nerve was mobilized. The depth of the field was widened by further cavernous exposure and the removal of the posterior clinoid. Temporary clips were applied to the basilar trunk perforator-free zone to preserve visualization of the aneurysm neck and perforators and to maintain collateral flow to the brainstem.

RESULTS:

Twenty-one high-complexity basilar apex aneurysms, 11 of which caused subarachnoid hemorrhage, were treated. Twenty (95%) were successfully clipped (Glasgow Outcome Scale scores, 4 or 5 in 90.5% at discharge; Rankin Disability Score, 1 in 90.5% at 1-yr follow-up). Complications were transient oculomotor palsy in all patients, small thalamic infarct in one patient, and cerebrospinal fluid leak in another. There was no surgical mortality. Delayed follow-up angiography in 19 of the 21 patients showed no residual aneurysm.

CONCLUSION:

We report the largest series of a unique, challenging group of complex basilar apex aneurysms treated with the pretemporal transzygomatic transcavernous approach, which provided improved safety of clipping by 1) increased visualization of the basilar apex and perforator arteries, 2) improved maneuverability of clip application, 3) a safer perforator-free location, and 4) preservation of brainstem collateral flow.

Evaluation of the Stability of Small Ruptured Aneurysms with a Small Neck after Embolization with Guglielmi Detachable Coils: Correlation between Coil Packing Ratio and Coil Compaction

OBJECTIVE:

Because it is difficult to predict the compaction of Guglielmi detachable coils (GDCs) after endovascular surgery for aneurysms, we studied the relationship between the coil packing ratio and compaction. Here, we propose a simple method for the preoperative estimation of coil compaction. Using follow-up angiograms, we studied the timing and degree of coil compaction in small terminal and side-wall aneurysms with narrow necks.

METHODS:

We studied 62 patients with acute ruptured intracranial aneurysms that were small (&lt;10 mm), had a small neck (&lt;4 mm), and were coil embolized with GDC-10s. The aneurysmal volume was calculated using the equation V = 4/3π(a/2) × (b/2) × (c/2), where a, b, and c are the aneurysmal height, length, and width in millimeters, respectively. The coil volume was calculated using the equation V = π(p/2)2 × l × 10, where p represents the GDC-10 coil diameter (0.25 mm) and l is the coil length. We recorded the maximum prospective coil length, L, as that corresponding with the volume of packed coils occupying 30% of the aneurysmal volume. Therefore, L was calculated as L (cm) = 0.3 × a × b × c, and the coil packing ratio was expressed as packed coil length/L × 100. Angiographic follow-up studies were generally performed at 3 months and 1 and 2 years after endovascular surgery. We considered coil compaction exceeding 2 mm as major compaction and recorded minor compaction when it was less than 2 mm of the empty reappeared space in the embolized aneurysm. Aneurysmal location was recorded as terminal or side wall.

RESULTS:

Of the 62 patients, 16 (25.8%) manifested angiographic coil compaction (10 minor and 6 major compactions); the mean coil packing ratio was 51.9 ± 13.4%. The mean coil packing ratio in the other 46 patients was 80.5 ± 20.2%, and the difference was statistically significant (P &lt; 0.01). In all 6 patients with major compaction, the mean packing ratio was less than 50% and all underwent re-embolization after a mean of 24.9 ± 1.1 months. The 10 patients with minor compaction were conservatively treated, and the degree of compaction did not change during a mean period of 24 months. We detected 93.8% of the compactions within 12 months of coil placement. The aneurysm was of the terminal type in 5 of the 6 patients with major coil compaction.

CONCLUSION:

In patients who underwent embolization with GDC-10s of aneurysms that were small and had a small neck, the optimal coil packing ratio could be identified with the formula 0.3 × a × b × c. The probability of coil compaction was significantly higher when the coil packing ratio was less than 50%. To detect coil compaction after embolization, follow-up angiograms must be examined regularly for at least 12 months. To detect major coil compaction in patients with terminal type aneurysms, angiographic follow-up should not be shorter than 24 months.

Upper basilar artery aneurysms: oculomotor outcomes in 163 cases

Object. The purpose of this study was to identify factors predictive of postoperative oculomotor nerve palsy among patients who undergo surgery for distal basilar artery (BA) aneurysms. The data can be used to estimate preoperative risk in this population. The natural history of oculomotor nerve palsy in patients with good outcomes is also defined.

Methods. The cases of 163 patients with distal BA aneurysms, who were treated surgically between 1996 and 2002, were retrospectively studied to identify factors contributing to oculomotor nerve palsy. After the data had been collected, stepwise logistic regression procedures were used to determine the predictive effects of each variable on the development of oculomotor nerve palsy and to create a scoring system. Factors that interfered with resolution of oculomotor dysfunction in patients with good outcomes were also studied.

Postoperative oculomotor nerve palsy occurred in 86 patients (52.8%) with distal BA aneurysms. The following factors were associated with postoperative oculomotor dysfunction, as determined by a categorical data analysis: 1) younger patient age (p < 0.001); 2) poor admission Hunt and Hess grade (p < 0.001); 3) use of temporary arterial occlusion (p < 0.001); 4) poor Glasgow Outcome Scale score (p < 0.001); and 5) the presence of a BA apex aneurysm that projected posteriorly (p < 0.001). For patients with good outcomes, postoperative oculomotor nerve palsy resolved completely within 3 months in 31 patients (52%) and within 6 months in 47 patients (80%). The projection of the BA aneurysm was associated with incomplete oculomotor recovery at 6 months postoperatively (p = 0.019).

Conclusions. The results of this study can help identify patients with a high risk for the development of oculomotor nerve palsy. This may help neurosurgeons in preoperative planning and discussions.

Cooperative study of ruptured vertebrobasilar artery aneurysms in the Tohoku district in Japan

A multicenter study investigated the clinical characteristics and overall outcome of 342 cases of ruptured vertebrobasilar artery aneurysms among 6783 ruptured intracranial berry aneurysms in 73 hospitals across the Tohoku district in Japan between 1992 and 1996. The incidence of ruptured vertebrobasilar artery aneurysms was less frequent than previously reported. The incidence was 5% among all intracranial berry aneurysms. One hundred eleven patients had aneurysms of the basilar artery bifurcation, 98 had vertebral-posterior inferior cerebellar artery aneurysms, 44 had basilar-superior cerebellar artery aneurysms, and 28 had distal posterior inferior cerebellar artery aneurysms. Aneurysm clipping was performed in 238 cases (70%), intravascular treatment in 22 (6%), drainage in 22 (6%), and conservative treatment in 60 (18%). Approximately 50% of patients were in good condition at admission. At 3-month follow up, 46% had good recovery, 14% had moderate disability, 10% had severe disability, 4% were vegetative state, and 27% died. Vertebral artery aneurysms showed favorable outcomes compared to basilar artery bifurcation aneurysms. Surgical results in the 238 operated cases were good recovery in 60%, moderate disability in 18%, severe disability in 10%, vegetative state in 2%, and death in 11% of cases. Worse postoperative outcomes were observed in patients with high preoperative Hunt and Kosnik grades or aneurysms larger than 10 mm, and in patients over 70 years of age.

Endovascular Treatment of Basilar Tip Aneurysms Using Guglielmi Detachable Coils: Anatomic and Clinical Outcomes in 73 Patients from a Single Institution

OBJECTIVE

Seventy-three consecutive patients with 75 basilar tip aneurysms were treated with Guglielmi detachable coil (GDC) technology. Their anatomic and clinical outcomes are discussed.

METHODS

Seventy-five basilar tip aneurysms were treated with the GDC system at the University of California, Los Angeles Medical Center from 1990 to 1999. The average age of the population was 48.3 years (range, 28–82 yr). Forty-two patients (57.5%) presented with acute subarachnoid hemorrhage, 8 patients (10.9%) had unruptured aneurysms with mass effect, and 23 patients (31.5%) had incidental aneurysms. Thirty-one aneurysms (41.3%) were small with a small neck, 18 (24%) were small with a wide neck, 16 (21.3%) were large, and 10 (13.3%) were giant aneurysms.

RESULTS

Immediate anatomic outcomes demonstrated complete or near-complete occlusion in 64 aneurysms (85.3%) and incomplete occlusion in 7 aneurysms (9.3%). Four aneurysms (5.3%) could not be embolized because of anatomic difficulties. Of the 69 patients treated with GDCs, 63 patients (91.3%) remained neurologically intact or unchanged from their initial clinical status. Procedure-related morbidity and mortality were 4.1% and 1.4%, respectively. Long-term follow-up angiograms were obtained in 41 patients with 42 aneurysms. Thirty aneurysms (71.4%) demonstrated complete or near-complete occlusion. One incompletely embolized giant aneurysm ruptured during the follow-up period.

CONCLUSION

In contrast to surgical clipping of basilar tip aneurysms, the main technical challenge of the Guglielmi detachable coiling procedure depends on the shape of the aneurysm, not its location. The results of this study indicate that endovascular GDC technology is an appropriate therapeutic alternative in ruptured or unruptured basilar tip aneurysms regardless of patient age, clinical presentation, clinical status, or timing of treatment.

Endovascular treatment of unruptured vertebro-basilar aneurysms

We reviewed 201 unruptured vertebro-basilar aneurysms encountered at our institute and 35 affiliated hospitals over the past 8 years. Of these, 106 aneurysms in 103 patients were treated with surgical or endovascular approaches: 43 aneurysms, surgically with clipping or wrapping; and 63 endovascularly with embolization. Outcome was excellent or good in 87 patients (84.5%). Among 24 patients with 36 complications, 16 had unfavorable outcomes including five deaths. Twelve patients (27.9%) with surgical treatment and two (3.3%) with endovascular treatment had unfavorable results because of treatment-related complications. Two patients with surgical treatment had complications related to perioperative management. Vascular occlusive complications were likeliest to occur in surgically treated basilar artery aneurysms (41%). Among surgically treated aneurysms the vertebral artery site was relatively associated with cranial nerve injuries. Complications numbered 36, occurring in 24 patients and 54% of complications affected outcome. Overall morbidity and mortality of surgical treatment were 18.6% and 7.0%, respectively, while those of endovascular treatment were 5.0% and 3.3%. In conclusion, complications of surgery tend to be serious and affect outcome, and endovascular treatment is safer than surgical for vertebro-basilar aneurysms. Embolizations are particularly advantageous for patients who are poor surgical risks.

Endovascular occlusion of basilar bifurcation aneurysms with electrolytically detachable coils

OBJECT

To describe the clinical and angiographic results of endovascular occlusion of basilar bifurcation aneurysms with electrolytically detachable coils, and to identify factors which should be considered in deciding upon surgical or endovascular treatment.

METHODS

We report our experience with 40 patients in whom occlusion of basilar bifurcation aneurysms with electrolytically detachable coils was attempted. All patients underwent superselective angiography and attempted embolization with Guglielmi detachable coils (GDCs). Angiographic and clinical results were prospectively recorded. Twenty-eight aneurysms presented with subarachnoid hemorrhage (SAH), 2 were symptomatic and 10 were incidental.

RESULTS

Coils were not placed in 10 patients (25%) because of unfavorable anatomy. Complete aneurysm occlusion was achieved at the time of the initial procedure in 13 (32.5%), small neck remnants were present in 13 (32.5%), and in 4 (10.0%) there was obvious residual contrast filling of the aneurysm body. Of 23 patients successfully coiled after SAH, 20 were Grade 1 to 3 and 3 were grade 4 or 5 at the time of treatment. Eighteen (78%) made a good recovery. Procedural mortality was 2.5% and permanent morbidity was 7.5%. There were no permanent complications in patients with unruptured aneurysms. Complete aneurysm occlusion was possible in 10 (56%) of 18 aneurysms with small necks and 3 (14%) of 22 with large necks. Follow-up angiography in 25 of 28 surviving patients (mean, 12 months) demonstrated stability of all completely occluded aneurysms. Incompletely coiled aneurysms had variable results on follow-up angiograms: 15.4% improved, 69.2% worsened, and 15.4% were stable. No aneurysm bled after treatment during clinical follow-up averaging 22 months.

CONCLUSIONS

Endovascular treatment of basilar bifurcation aneurysms appears to prevent early aneurysm rebleeding with acceptable rates of morbidity and mortality, but long-term follow-up is required.

Multivariate analysis of predictors of cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The role of type of treatment on cerebral vasospasm occurrence after aneurysmal subarachnoid hemorrhage (SAH) has not been studied. Through multivariate analysis we determined the independent prognostic factors of the occurrence of symptomatic vasospasm following aneurysmal SAH in a study cohort of 244 patients undergoing either surgical or endovascular treatment. The prognostic factors of sequelae after aneurysmal SAH were studied as well.

METHODS

Symptomatic vasospasm was defined as the association of deterioration in a patient's neurological condition between 3 and 14 days after SAH with no other explanation and an increase in mean transcranial Doppler velocities of >120 cm/s. The prognostic factors were registered on admission and during the intensive care stay.

RESULTS

Symptomatic vasospasm occurred in 22.2% surgical patients compared with 17.2% endovascular treatment patients (P=0.37). Multivariate analysis revealed that the probability of occurrence of symptomatic vasospasm decreased with age >50 years (relative risk [RR], 0.47 [0.25 to 0.88]) and severe World Federation of Neurological Surgeons (WFNS) grade measured on admission (RR, 0.43 [0.20 to 0.90]) and increased with hyperglycemia occurring during the intensive care stay (RR, 1.94 [1.04 to 3.63]). No difference in risk of symptomatic vasospasm could be identified between surgical and endovascular treatment. Symptomatic vasospasm (OR, 4.73 [CI, 1. 77 to 12.6]) as well as WFNS grade of >2 (OR, 8.95 [3.46 to 23.2]), treatment complications (OR, 8.39 [3.16 to 22.3]), and secondary brain insults were associated with an increased risk of 6-month sequelae.

CONCLUSIONS

Age <50 years, good neurological grade, and hyperglycemia were all associated with an increased risk of cerebral vasospasm whereas treatment was not. This provides a basis for future clinical prospective randomized trials comparing both treatments.

Treatment of basilar artery bifurcation aneurysms by using Guglielmi detachable coils: a 6-year experience

OBJECT

The authors retrospectively analyzed the results of their 6-year experience in the treatment of basilar artery (BA) bifurcation aneurysms by using Guglielmi detachable coils (GDCs).

METHODS

This analysis involved 45 BA tip aneurysms in 16 men and 29 women who ranged in age from 23 to 78 years (mean 50 years). Seventy-five percent of the aneurysms had ruptured and 25% remained unruptured. Of the group whose aneurysms hemorrhaged, 14 patients were Hunt and Hess Grade I or II and 20 were Hunt and Hess Grades III to V; 32 patients were treated within 2 weeks of their subarachnoid hemorrhage (SAH). Initially, treatment with GDCs was limited to poor-grade high-risk patients who refused surgery or patients in whom surgery proved unsuccessful. Later in the study, good-grade patients with narrow-necked aneurysms were also treated using GDCs. The length of clinical follow up ranged from 1 to 72 months (average 27.4 months) in the 37 surviving patients. In 33 of the 45 aneurysms treated with coil placement, good to excellent results were achieved. There were 12 poor results (27%) including one in a patient from the non-SAH group who suffered a thrombotic complication due to an underlying vasculitis. Eight deaths were recorded in this group of 45 patients. One of these deaths was caused by a complication related to anesthesia, one by unknown causes, and six resulted from complications of the disease. One patient rebled on the 2nd day after the endovascular procedure. The mortality and permanent morbidity rates directly related to the intervention were 2.2% and 4.4%, respectively. Angiographic studies obtained immediately postintervention demonstrated 99 to 100% occlusion in 30 (67%) of the aneurysms; nine (20%) were more than 90% occluded; and six (13%) were less than 90% occluded by the GDCs. Follow-up angiograms were obtained in 31 patients between 2 and 72 months after coil placement. Nineteen (61%) of the follow-up angiograms revealed stable results (that is, no change from initial treatment). Twelve of the 31 showed coil compaction, but only eight of these lesions could accept additional coils. In large aneurysms recanalization was seen in 57%, and some of the larger lesions required as many as four embolizations (mean 1.7) to achieve optimal occlusion. When small-necked aneurysms were analyzed as a subset, a stable angiographic result was seen in 92%.

CONCLUSIONS

Use of GDCs led to excellent clinical and angiographic results in the majority of patients with BA tip aneurysms included in this limited follow-up study. Rebleeding was encountered in one of the 34 previously ruptured BA aneurysms treated with GDCs, and no hemorrhages have been documented in the 11 unruptured aneurysms treated with GDCs in this series. Long-term follow-up studies are necessary before it is possible to compare adequately the treatment of aneurysms with coil placement to the gold standard of aneurysm clipping.

A comparison between endovascular and surgical management of basilar artery apex aneurysms

OBJECT

The goal of this retrospective study was to evaluate endovascular treatment by means of Guglielmi detachable coils (GDCs) compared with surgical management for basilar artery (BA) apex aneurysms.

METHODS

Forty-one patients presented with saccular BA apex aneurysms with angiographically definable necks that were judged suitable for either treatment. Of 20 patients who underwent surgery and 21 who underwent GDC embolization, 15 (75%) and 11 (52%), respectively, were treated in the acute phase after subarachnoid hemorrhage (SAH). Twenty-four (92%) of the 26 patients presenting with an SAH had a Hunt and Hess Grade III or better. Fifteen patients with unruptured or ruptured aneurysms more than 14 days post-SAH were treated electively. Patients in the endovascular and surgical treatment groups had aneurysms with comparable dimensions and configurations. Overall, 15 (75%) of the surgical patients and 20 (95%) of the patients in whom GDC embolization was performed had a good outcome (Glasgow Outcome Scale score of 4 or 5). Among those patients treated in the acute stage post-SAH, 11 (73%) of the surgical group and 10 (91%) of the endovascular group did well. Fourteen patients treated electively (93%) had good outcomes. There were two deaths (10%) in the surgical group and none in the endovascular group. Patients treated surgically were hospitalized twice as long and incurred twice the expenses of patients who underwent endovascular treatment (p<0.001).

CONCLUSIONS

Endovascular GDC embolization of select BA apex aneurysms may be a competitive alternative to direct surgical clipping. Long-term follow up is needed to better define the natural history of the endovascularly treated aneurysm and to further evaluate the accuracy of these preliminary results.

Oculomotor nerve palsy after surgery for upper basilar artery aneurysms

OBJECTIVE

The goals of this study were to evaluate the relationship between postoperative oculomotor nerve palsy and other clinical factors and to improve preoperative estimations of the risk. Such an evaluation has not been previously described in the literature.

METHODS

Patient records for 77 basilar tip aneurysm cases and 28 basilar superior cerebellar artery aneurysm cases treated between 1981 and 1997 were reviewed. Clinical and radiological parameters were separately analyzed using the chi2 test, and then multiple-regression analysis was used.

RESULTS

Postoperative oculomotor palsy occurred in 25 (32%) patients with basilar tip aneurysms and 11 (39%) patients with basilar superior cerebellar artery aneurysms, in addition to 2 patients with basilar tip aneurysms and 3 patients with basilar superior cerebellar artery aneurysms who exhibited oculomotor palsy before surgery. For both type of aneurysms, the size and direction of the aneurysms were closely related to oculomotor nerve palsy. The complication also tended to occur in early surgery cases, in younger patients, and in patients of poor-clinical grade status.

CONCLUSION

In this study, some clinical and radiological factors were found to be associated with postoperative oculomotor nerve palsy.