Effect of Clipping, Craniotomy, or Intravascular Coiling on Cerebral Vasospasm and Patient Outcome after Aneurysmal Subarachnoid Hemorrhage

Association of a younger age with an increased risk of angiographic and symptomatic vasospasms following subarachnoid hemorrhage

Object

Vasospasm is a leading cause of morbidity and death following aneurysmal subarachnoid hemorrhage (SAH). It is important to predict which patients are at risk for vasospasm so that interventions can be made. There are several potential risk factors for vasospasm, one of which is age. However, the effect of age on vasospasm, particularly symptomatic vasospasm, remains controversial.

Methods

Three hundred ninety-one patients were retrospectively identified from a prospective observational database of patients with SAH who had been admitted to a single center. Demographic and clinical data were recorded, and cerebral angiograms obtained at admission and between 5 and 10 days later were compared. The relationship between age and angiographic and symptomatic vasospasms was examined using logistic regression techniques.

Results

Mild (86 patients), moderate (69 patients), severe (56 patients), and no angiographic vasospasms (180 patients) were documented by comparing admission and follow-up angiograms in each patient. Symptomatic vasospasm was identified in 69 patients (17.6%). Angiographic vasospasm was more frequent as age decreased. Except in patients < 30 years old, the frequency of symptomatic vasospasm also increased with decreasing age (p = 0.0001). After adjusting for variables known to be associated with vasospasm, an advanced age was associated with a reduced incidence of any angiographic vasospasm (OR 0.96, 95% CI 0.94–0.97), severe angiographic vasospasm (OR 0.96, 95% CI 0.95–0.98), and symptomatic vasospasm (OR 0.98, 95% CI 0.96–0.99).

Conclusions

Results in this study show that a younger age is associated with an increased incidence of angiographic and symptomatic vasospasm.

Prediction of 60 day case-fatality after aneurysmal subarachnoid haemorrhage: results from the International Subarachnoid Aneurysm Trial (ISAT)

Aneurysmal subarachnoid haemorrhage (aSAH) is a devastating event with substantial case-fatality. Our purpose was to examine which clinical and neuro-imaging characteristics, available on admission, predict 60 day case-fatality in aSAH and to evaluate performance of our prediction model. We performed a secondary analysis of patients enrolled in the International Subarachnoid Aneurysm Trial (ISAT), a randomised multicentre trial to compare coiling with clipping in aSAH patients. Multivariable logistic regression analysis was used to develop a prognostic model to estimate the risk of dying within 60 days from aSAH based on clinical and neuro-imaging characteristics. The model was internally validated with bootstrapping techniques. The study population comprised of 2,128 patients who had been randomised to either endovascular coiling or neurosurgical clipping. In this population 153 patients (7.2%) died within 60 days. World Federation of Neurosurgical Societies (WFNS) grade was the most important predictor of case-fatality, followed by age, lumen size of the aneurysm and Fisher grade. The model discriminated reasonably between those who died within 60 days and those who survived (c statistic = 0.73), with minor optimism according to bootstrap re-sampling (optimism corrected c statistic = 0.70). Several strong predictors are available to predict 60 day case-fatality in aSAH patients who survived the early stage up till a treatment decision; after external validation these predictors could eventually be used in clinical decision making.

Cost-effectiveness of clipping vs coiling of intracranial aneurysms after subarachnoid hemorrhage in a developing country--a prospective study

BACKGROUND

Endovascular coil treatment is being used increasingly as an alternative to clipping for some ruptured intracranial aneurysms. The relative benefits of these 2 approaches have yet to be fully established. The aim of this study was to compare the clinical outcome, resource consumption, and cost-effectiveness of endovascular treatment vs surgical clipping in a developing country.

METHODS

The study population consisted of 55 patients with aneurysmal subarachnoid hemorrhage (SAH) identified prospectively from January 2004 to June 2007. Of the 55 patients with ruptured intracranial aneurysms, 31 underwent surgical clipping, whereas 24 were treated via interventional coils. Clinical outcome at 6 months, using the modified Rankin Scale, and cost of treatment related to all aspects of the inpatient stay were evaluated in both groups.

RESULTS

The average age of the patients in the endovascular group was 38 years, whereas in the surgical group, it was 45 years. Most patients (43) were found to be in grades (1 and 2). Of these patients, 18 received coils and 25 were clipped. The remaining 12 patients were of poor grades (3 and 4), of which 6 had coiling and 6 underwent clipping. Most the patients (46/55) had anterior circulation aneurysms, and the rest of the patients (9/55) had posterior circulation aneurysms. The clinical outcome was similar in comparison (good in 81% for clipping and 83% for coiling). The average total cost for patients undergoing endovascular treatment of the aneurysms was $5080, whereas the average total cost of surgical clipping was $3127.

CONCLUSION

Patients with aneurysmal SAH whom we judged to require coiling had higher charges than patients who could be treated by clipping. The benefits of apparent decrease in length of stay in the endovascular group were offset by higher procedure price and cost of consumables. There was no significant difference in clinical outcome at 6 months. We have proposed a risk scoring system to give guidelines regarding the choice of treatment considering size of aneurysm and resource allocation.

Prognostic value of histopathological findings in aneurysmal subarachnoid hemorrhage

OBJECT

Aneurysmal subarachnoid hemorrhage (SAH) carries a severe prognosis, which is often related to the development of cerebral vasospasm. Even though several clinical and radiological predictors of vasospasm and functional outcome have been established, the prognostic value of histopathological findings remains unclear.

METHODS

Histopathological findings in resected distal aneurysm walls were examined, as were the clinical and radiological factors in a series of 91 patients who had been neurosurgically treated for aneurysmal SAH. The impact of the histological, clinical, and radiological factors on the occurrence of vasospasm and functional outcome at discharge was analyzed.

RESULTS

Histopathological findings frequently included lymphocytic infiltrates (60%), fibrosis (60%), and necrosis (50%) of the resected aneurysm wall. On univariate analysis, clinical (Hunt and Hess grade) and radiological (aneurysm size) factors as well as histopathological features-namely, lymphocytic infiltrates and necrosis of the aneurysm wall-were significantly associated with the occurrence of vasospasm. On multivariate analysis, lymphocytic infiltrates (OR 6.35, 95% CI 2.32-17.36, p = 0.0001) and aneurysm size (OR 1.22, 95% CI 1.05-1.42, p = 0.009) remained the only factors predicting the development of vasospasm. A poor functional outcome at discharge was significantly associated with vasospasm, other clinical factors (Hunt and Hess grade, alcohol consumption, hyperglycemia, and elevated white blood cell count [WBC] at admission), and radiological factors (Fisher grade and aneurysm size), as well as with histopathological features (lymphocytic infiltrates [p = 0.0001] and necrosis of the aneurysm wall [p = 0.0015]). On multivariate analysis taking into account all clinical, radiological, and histological factors; vasospasm (OR 9.82, 95% CI 1.83-52.82, p = 0.008), Hunt and Hess grade (OR 5.61, 95% CI 2.29-13.74, p = 0.0001), patient age (OR 1.09, 95% CI 1.02-1.16, p = 0.0013), elevated WBC (OR 1.29, 95% CI 1.01-1.64, p = 0.04), and Fisher grade (OR 4.35, 95% CI 1.25-15.07, p = 0.015) best predicted functional outcome at discharge.

CONCLUSIONS

The demonstration of lymphocytic infiltrates in the resected aneurysm wall is of independent prognostic value for the development of vasospasm in patients with neurosurgically treated aneurysmal SAH. Thus, histopathology might complement other clinical and radiological factors in the identification of patients at risk.

Peri-operative measures for treatment and prevention of cerebral vasospasm following subarachnoid hemorrhage

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high early mortality rates. Cerebral vasospasm remains the major source of morbidity after aSAH. Angiographic evidence of vasospasm is apparent in 70% of patients, while clinical manifestation of vasospasm is present in one third of patients. Early or existing vasospasm at the time of presentation poses an additional challenge in the management of the patient, and forms the basis for this review.

METHODS

Treatment modalities for management of ruptured aneurysms in the setting of vasospasm, including timing of aneurysm surgery and peri-operative management, are reviewed. Intraoperative measures aimed at treatment of existing vasospasm and at the prevention of vasopasm are discussed.

RESULTS

Operative/endovascular means to secure the ruptured aneurysm should be performed as soon as possible to facilitate treatment of the vasospasm. Surgery performed in the presence of angiographic/symptomatic vasospasm can be associated with good outcome. Operative measures to decrease the incidence of vasospasm include clot removal, intracisternal injection of thrombolytics, fenestration of the lamina terminalis and local application of vasodilatory agents. Post-operative measures include early intra-arterial injection of vasodilators (verapamil or nicardipine), percutaneous angioplasty, triple-H therapy and CSF drainage.

DISCUSSION

The utilization of a multimodality approach to treat patients with aneurysmal subarachnoid hemorrhage presenting with existing vasospasm can result in good outcome.

The effect of lumboventricular lavage and simultaneous low-frequency head-motion therapy after severe subarachnoid hemorrhage: results of a single center prospective Phase II trial

Object

The authors of recent publications have suggested that a combination of cisternal irrigation and head-shaking therapy might reduce cerebral vasospasm after subarachnoid hemorrhage (SAH) and therefore improve outcome. The authors undertook this prospective nonrandomized Phase II study to analyze the effect of enhanced washout by lumboventricular irrigation in combination with head motion (lateral rotational therapy) on the clot clearance (CC) rate, development of cerebral vasospasm, and clinical outcome.

Methods

Forty patients with aneurysmal SAHs of World Federation of Neurosurgical Societies Grades II–V (Glasgow Coma Scale Scores 13–3) and Fisher Grade 3 or 4 were included in this study. The study and control groups each consisted of 20 patients. The protocol in the study group, after the aneurysm was secured and a ventricular drain inserted, included the insertion of 2 lumbar catheters for intrathecal irrigation with Ringer solution and intrathecal pressure monitoring. Moderate head rotation in a kinetic system was also applied and was continued for 5 days. The CC rate was monitored on daily computed tomography (CT) scans. Vasospasms were identified clinically with a focus on delayed ischemic neurological deficits (DINDs), daily transcranial Doppler (TCD) ultrasonography studies, and analysis of infarction rate on CT and cerebral angiography. The data obtained in both groups were statistically evaluated.

Results

There were no procedure-related complications. The overall CC rate did not differ significantly between the groups, but there was a trend toward accelerated resolution in the study group. During observation, a new neurological deficit developed in 1 patient (5%) in the study group and 4 patients (20%) in the control group. Ischemic areas on CT scans related to vasospasm were demonstrated in 2 patients (10%) in the study group and 6 patients (30%) in the control group. The incidence of angiographic vasospasm was approximately the same in both groups. The pooled TCD flow velocities measured over a period of 14 days showed lower mean values in the study group than in the control group (p = 0.00002). The clinical outcome in the study group as evaluated with the modified Rankin scale was better in the study group than in the control group after 3 (p = 0.008) and 6 (p = 0.005) months.

Conclusions

The present study demonstrates that a combination of lumboventricular lavage and mechanical head motion reduces vasospasm on TCD ultrasonography, the incidence of DIND, and secondary infarctions on CT and improves clinical outcome. No obvious effect could be found on the rate of angiographic vasospasm.

Prehemorrhage statin use and the risk of vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Aneurysmal SAH is often followed by delayed ischemic deficits attributable to cerebral vasospasm. Recent studies suggest a positive impact of statin therapy on the incidence of vasospasm. This study was designed to assess whether a history of prior use of statin therapy was associated with a lower risk of vasospasm in patients with SAH.

METHODS

We performed a comprehensive retrospective review of patients with aneurysmal SAH between 1997 and 2004. Clinical demographics and imaging data for all patients were reviewed, and a logistic regression analysis was performed to identify the predictors of cerebral vasospasm, defined as a combination of clinical signs with radiographic confirmation.

RESULTS

Three hundred eight patients were included. Mean age was higher in the group receiving statins (64 +/- 12 vs 54 +/- 12 years). Hunt and Hess scores and treatment modality were not significantly different between the groups. Vasospasm was observed in 31% of patients not taking a statin (n = 282) vs 23% taking a statin (n = 26), without achieving statistical significance. Discontinuation of the statin did not affect risk of vasospasm.

CONCLUSIONS

Use of a statin prior to an aneurysmal SAH trended to reduce the incidence of subsequent vasospasm, without achieving statistical significance.

Endovascular embolization of intracranial aneurysms

Intracranial aneurysm (ICA) is a common condition but with a high mortality rate when rupture occurs. The treatment of ruptured or unruptured ICA, especially with an endovascular approach, has been evolving rapidly. The current generally accepted opinion suggests that endovascular embolization is an effective technique for preventing the recurrence of aneurysm rupture, but the rebleeding rate after endovascular embolization is found to be higher than that after surgical clipping. In addition, long-term follow-up data are required for the evaluation of the effectiveness of endovascular treatment in unruptured ICA. This review presents the current understanding of ICA, the selection of optimal treatment approaches, and in particular, the advances in endovascular embolization in the treatment of ICA, including embolic materials, therapeutic and assisting techniques, long-term effectiveness, and limitations.

Endovascular treatment of ruptured aneurysms and vasospasm

Despite various criticisms, the International Subarachnoid Aneurysm Trial (ISAT) has provided Class I evidence that endovascular therapy (EVT) results in superior 1-year outcomes, compared with surgical repair of ruptured aneurysms equally amenable to both types of treatment. Although the lower occlusion rates and higher rates of recanalization in aneurysms treated with EVT necessitate serial imaging follow-up, these findings do not seem to translate into unacceptably high rates of rebleeding or retreatment morbidity that outweigh the upfront advantage over surgical clipping. EVT also compares favorably to surgery in the treatment of unruptured aneurysms. A randomized, controlled study similar to ISAT is needed for comparing EVT to surgery. EVT appears to have more limitations of durability in large and giant aneurysms, which warrants further research into stent or liquid embolic-assisted treatment because surgical treatment morbidity is also high. Vasospasm is a frequent and potentially devastating complication of aneurysmal subarachnoid hemorrhage. Angioplasty and intra-arterial drug therapy are effective treatments, with an acceptable morbidity and mortality. Angioplasty is more effective and durable and should be considered early in patients with signs of ischemia refractory to maximal medical therapy.

Outcomes of ruptured intracranial aneurysms treated by microsurgical clipping and endovascular coiling in a high-volume center

BACKGROUND AND PURPOSE

The purpose of this study was to analyze the 3-month outcomes of patients with aneurysmal subarachnoid hemorrhage (SAH) treated from January 2005 to June 2006. This paper describes the outcomes after treatment of aneurysmal SAH and comparison between patients treated by clipping or coiling in a high volume center.

MATERIALS AND METHODS

A retrospective chart review was performed of records of 195 consecutive patients with SAH. The overall outcome and the pretreatment variables predicting outcomes and the difference between the clipping and coiling groups were analyzed by logistic regression analysis.

RESULTS

A total of 105 (55%) patients had microsurgical clipping and 87 (45%) had endovascular coiling. At 3 months, 69% of patients recovered with no or mild disability. The predictors of a 3-month modified Rankin Scale (mRS) were Hunt and Hess (HH) grade on admission and the presence of intracerebral hemorrhage (ICH). Patients in the coiling group had worse admission grades; they had worse 3-month mRS (2.28 vs 1.73), but this was not significant when the groups were matched (P = .38). Vasospasm rate was significantly higher in the clipping group (66% vs 52%). The immediate incomplete occlusion rate of aneurysms was higher (21.7% vs 7.6%) in the coiling group.

CONCLUSION

The overall results of treatment of aneurysmal SAH have improved. There is no significant difference in the outcomes between the patients in the clipping and coiling groups.

Comparison of endovascular and surgical treatments for intracranial aneurysms: an evidence-based review

Intracranial aneurysms can be treated with endovascular or surgical techniques. We provide an objective comparison of these treatments, using data from single-centre studies, multicentre studies with and without independent outcome ascertainment, and randomised clinical trials. We compared the outcomes of patients who were candidates for endovascular treatment, surgical treatment, or both. In patients with ruptured intracranial aneurysms, rates of aneurysm obliteration were higher, and need for second treatment was lower, after surgery than after endovascular treatment. However, in observational studies and randomised trials, outcome at discharge, at 2-6 months, and at 1 year, and later survival, were all better after endovascular treatment than after surgery. The results suggest that the higher rates of incomplete obliteration and retreatment after endovascular treatment do not affect patients' clinical outcome. In observational studies of patients with unruptured intracranial aneurysms, discharge outcomes were better and hospital costs were lower after endovascular treatment than after surgery. These patients showed no difference between the two treatments in 1-year outcomes and later rebleeding, although few data were available for this comparison.

Thrombus organization and healing in an experimental aneurysm model. Part II. The effect of various types of bioactive bioabsorbable polymeric coils

OBJECT

Bioabsorbable polymeric material coils are being used in the endovascular treatment of aneurysms to achieve better thrombus organization than is possible using bare platinum coils. We used immunohistochemical and molecular biological analysis techniques in experimental aneurysms implanted with three different bioabsorbable polymer coils and platinum coils.

METHODS

The degradation kinetics of nine polymer candidates for further analysis were first analyzed in vitro, and three materials with different degradation rates were selected. Seventy-four aneurysms were created in 37 swine using the venous pouch technique. The aneurysms were surgically implanted with one of the materials as follows (time points = 3, 7, and 14 days): Group 1, Guglielmi detachable coils (platinum); Group 2, Polysorb (90:10 polyglycolic acid [PGA]/polylactic acid); Group 3, Maxon (PGA/trimethylene carbonate); and Group 4, poly-l-lactic acid. Histological, immunohistochemical, and cDNA microarray analyses were performed on tissue specimens.

RESULTS

Groups 1 and 4 showed minimal inflammatory response adjacent to the coil mass. In Group 2, Polysorb elicited a unique, firm granulation tissue that accelerated intraaneurysmal thrombus organization. In Group 3 intermediate inflammatory reactions were seen. Microarray analysis with Expression Analysis Sytematic Explorer software showed functional-cluster-gene activation to be increased at Day 7, preceding the histologic manifestation of polymer-induced granulation tissue at Day 14. A profile of expression changes in cytokine-related and extracellular membrane-related genes was compiled.

CONCLUSIONS

Degradation speed was not the only factor determining the strength of the biological response. Polysorb induced an early, unique granulation tissue that conferred greater mechanical strength to the intraaneurysmal coilthrombus complex. Enhancing the formation of this polymer-induced granulation tissue may provide a new direction for improving long-term anatomical outcomes in cases involving aneurysms embolized with detachable coils.

Relation among aneurysm size, amount of subarachnoid blood, and clinical outcome

Object

The authors of recent reports have suggested that smaller aneurysms are associated with more extensive sub-arachnoid hemorrhage (SAH), which could potentially presage poor outcome in patients harboring these lesions. The authors reviewed their clinical experience to determine if this theory has a basis in truth.

Methods

The authors undertook a retrospective review of a consecutive series of patients with aneurysmal SAH. Computed tomography scans and angiograms were studied to establish SAH scores and aneurysm size.

Results

One hundred thirty-three patients were treated during a 2-year period (January 2003–December 2004). There were 101 female and 32 male patients whose mean age was 56.7 years. The location distribution of aneurysms that bled was as follows: anterior communicating artery (56 cases), posterior communicating artery (34 cases), middle cerebral artery (21 cases), posterior circulation (16 cases), and paraclinoid region (six cases). The mean aneurysm size was 6.2 mm (range 2–26 mm). The mean SAH score was 18.3 (not normally distributed, p < 0.01, D'Agostino–Pearson test). One hundred three patients underwent surgical exploration and placement of an aneurysm clip, 21 underwent deployment of a coil, and two underwent both therapies; seven patients died prior to intervention.

No correlation was found between aneurysm size and SAH score (rS = −0.023, p = 0.8) or between small aneurysm size and poor Glasgow Outcome Scale score (p = 0.13). In fact, the trend was the opposite. The SAH score did, however, correspond strongly with the admission Hunt and Hess grade (p < 0.0001), indicating the strong correlation between grade and volume of intracranial blood. Outcome was best explained in the multivariate analysis by the following factors: admission Hunt and Hess grade, age, and clinical vasospasm (p < 0.0001) with the proportion of cases correctly classified as 79.7%.

Conclusions

Evaluation of the results in the present clinical series suggests that there is no relation between aneurysm size and volume of subarachnoid blood. The volume of cisternal blood correlates with Hunt and Hess grade but is not an independent determinant of outcome. Outcome is related to the following triad of well-established clinical factors: Hunt and Hess grade, age, and clinical vasospasm.

ENDOVASCULAR COIL EMBOLIZATION OF RUPTURED AND UNRUPTURED POSTERIOR CIRCULATION ANEURYSMS

OBJECTIVE

Treatment of posterior circulation aneurysms poses a great technical challenge for the practicing neurosurgeon. The advent of endovascular techniques has made such treatment more feasible. We report our experience with the endovascular management of ruptured and unruptured posterior circulation aneurysms during the past 10 years.

METHODS

A retrospective analysis was performed on all patients with posterior circulation aneurysms undergoing endovascular treatment at Jefferson Hospital for Neuroscience between July 1995 and December 2005. This yielded 275 patients (67 men and 208 women). The degree of aneurysm occlusion was determined by the operating endovascular neurosurgeon at the time of the procedure. Successful embolization was defined as greater than 95% occlusion of the dome without any coil prolapsing into the parent vessel. Clinical outcome was evaluated using the modified Glasgow Outcome Scale. Clinical follow-up data was obtained for 262 patients (95.3%); the follow-up period ranged from 1 to 94 months (mean, 31.8 mo for procedures performed before 2004 and 13.3 mo for procedures performed during 2004 and 2005). Angiographic follow-up data was obtained for 224 patients (84.8%) for periods ranging from 6 to 94 months (mean, 31.3 mo for procedures performed before 2004 and 13.7 mo for procedures performed during 2004 and 2005).

RESULTS

Based on the Hunt and Hess grading scale, the patient population included 106 patients (38.5%) with unruptured aneurysms, 43 patients (15.6%) with Grade I aneurysms, 16 patients (5.8%) with Grade II aneurysms, 56 patients (20.5%) with Grade III aneurysms, and 54 patients (19.6%) with Grade IV aneurysms. The locations of the posterior circulation aneurysms included 189 (68.7%) in the basilar apex or posterior cerebral artery, 23 (8.4%) in the basilar trunk/anterior inferior cerebellar artery, 22 (8%) in the superior cerebellar artery, and 41 (14.9%) in the vertebral artery or posterior inferior cerebellar artery. Of the 275 patients, 208 (76%) were women and 67 (24%) were men. The mean age at the time of treatment was 53.9 years (range, 7–90 yr). Of all patients treated, 237 patients (87.8%) had successful embolization (&gt;95% occlusion of the dome). On angiographic follow-up, 55 patients (24.5%) developed recanalization of at least 5%. Retreatment was required in 11 patients (4.9%; 0.01%/patient yr) and rehemorrhage occurred in three patients (1.1%; 0.003%/patient yr). Clinical follow-up was graded using the modified Glasgow Outcome Scale (mGOS) and revealed 229 patients (87.4%) in the mGOS I category, 12 patients (4.6%) in the mGOS II category, eight patients (3%) in the mGOS III category, two patients (0.8%) in the mGOS IV category, and 11 patients (4.2%) were deceased (mGOS V). Clinically significant vasospasm requiring angioplasty occurred in 11 patients (6.5%) with subarachnoid hemorrhage, and 120 patients (71%) with subarachnoid hemorrhage required ventricular shunts. Complications causing clinical morbidity occurred in 14 patients (5.1%) and ranged from postoperative ischemia to recurrent subarachnoid hemorrhage. Of all clinical factors evaluated, Hunt and Hess grade was the strongest predictor of good clinical outcome (P &lt; 0.0001).

CONCLUSION

Endovascular coil embolization of posterior circulation aneurysms is an effective treatment in the short term but is associated with recurrence, which requires close surveillance, possible retreatment, and can, albeit very rarely, lead to rehemorrhage. Future technological advancements such as the development of biologically active coils will be essential in the permanent obliteration of aneurysms.

Comparison between clipping and coiling on the incidence of cerebral vasospasm after aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

Cerebral vasospasm is one of the most important complications of aneurysmal subarachnoid hemorrhage. The effect of aneurysm occlusion technique on incidence of vasospasm is not exactly known. The objective was to analyze surgical clipping versus endovascular coiling on the incidence of cerebral vasospasm and its consequences. Using the MEDLINE PubMed (1966-present) database, all English-language manuscripts comparing patients treated by surgical clipping with patients treated by endovascular coiling, regarding vasospasm incidence after aneurysmal subarachnoid hemorrhage, were analyzed. Data extracted from eligible studies included the following outcome measures: incidence of total vasospasm, symptomatic vasospasm, ischemic infarct vasospasm-induced and delayed ischemic neurological deficit (DIND). A pooled estimate of the effect size was computed and the test of heterogeneity between studies was carried out using The Cochrane Collaboration's Review Manager software, RevMan 4.2. Nine manuscripts that fulfilled the eligibility criteria were included and analyzed. The studies differed substantially with respect to design and methodological quality. The overall results showed no significant difference between clipping and coiling regarding to outcome measures. According to the available data, there is no significant difference between the types of technique used for aneurysm occlusion (clipping or coiling) on the risk of cerebral vasospasm development and its consequences.

Endovascular embolization vs surgical clipping in treatment of cerebral aneurysms: morbidity and mortality with short-term outcome

BACKGROUND

Endovascular embolization of cerebral aneurysms has evolved rapidly worldwide within the last years, and has gained more popularity at the expense of surgical clipping; however, both regimens have inherent risks. This study was undertaken to asses the cerebral complications associated with both modalities of cerebral aneurysm treatment.

METHODS

We retrospectively reviewed the charts, operative and embolization reports, and imaging of patients who underwent surgical clipping or embolization for cerebral aneurysms at our institution between October 2001 and October 2004. Patients were divided into 2 groups: group A, patients who had confirmed subarachnoid hemorrhage; group B, patients with unruptured cerebral aneurysms. Patients belonging to group A were evaluated according to the Hunt and Hess scale with their computed tomography scan evaluated according to Fisher scale. Short-term outcome was measured with Glasgow Outcome Scale for both groups.

RESULTS

One hundred thirty-three patients with 168 aneurysms were treated; 95 (71.4%) were women and 38 (28.6%) men; mean age was 60.28 years. Hypertension (29.6%) was the most commonly encountered risk factor; average size of aneurysms treated was 7.21 mm; 53 patients belonged to group A. Seven patients were Hunt and Hess grade I, 23 grade II, 11 grade III, 7 grade IV, and 5 grade V. Eighty patients belonged to group B; for both groups, the periprocedural technical complication rate associated with coiling was 8.4% vs 19.35% with clipping. Follow-up angiographic results were better with clipping, as total aneurysm occlusion was 81.4% vs 57.5% with coiling. In group A, the incidence of angiographic vasospasm was 17.4% vs 45.4% with coiling vs clipping, whereas the incidence of shunt-dependant hydrocephalus was comparable with embolization and clipping. In group A, excellent outcome was achieved in 62% vs 44% (endovascular vs surgical) of subgroups, whereas in group B, it was 93% vs 81%, respectively.

CONCLUSION

With rapidly evolving technology of endovascular embolization, accumulated experience, and good selection of patients with optimum angioanatomical criteria and endovascular accessibility, our results of morbidity and mortality associated with both modalities of cerebral aneurysm treatment with short-term outcome show that endovascular embolization of cerebral aneurysms is a safe alternative to surgical clipping in the treatment of both ruptured and unruptured cerebral aneurysms; however, long-term outcome needs to be evaluated.

Endovascular treatment strategies for cerebral vasospasm

Cerebral vasospasm is a significant cause of morbidity and mortality in patients who have sustained a subarachnoid hemorrhage from aneurysm rupture. Symptomatic cerebral vasospasm is also a strong predictor of poor clinical outcome and has thus drawn a great deal of interest from cerebrovascular surgeons. Although medical management is the cornerstone of treatment for this condition, endovascular intervention may be warranted for those in whom this treatment fails and in whom symptomatic vasospasm subsequently develops. The rapid advancements in endovascular techniques and pharmacological agents used to combat this pathological state continue to offer promise in broadening the available treatment armamentarium. In this article the authors discuss the rationale and basis for using the various endovascular options for the treatment of cerebral vasospasm, and they also discuss the limitations, complications, and efficacy of these treatment strategies in regard to neurological condition and outcome.

Computed tomography grading schemes used to predict cerebral vasospasm after aneurysmal subarachnoid hemorrhage: a historical review

✓The elucidation of predictive factors of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is a major area of both clinical and basic science research. It is becoming clear that many factors contribute to this phenomenon. The most consistent predictor of vasospasm has been the amount of SAH seen on the postictal computed tomography scan. Over the last 30 years, it has become clear that the greater the amount of blood within the basal cisterns, the greater the risk of vasospasm. To evaluate this risk, various grading schemes have been proposed, from simple to elaborate, the most widely known being the Fisher scale. Most recently, volumetric quantification and clearance models have provided the most detailed analysis. Intraventricular hemorrhage, although not supported as strongly as cisternal SAH, has also been shown to be a risk factor for vasospasm.

Can angiographic vasospasm be used as a surrogate marker in evaluating therapeutic interventions for cerebral vasospasm?

✓ The authors tested the null hypothesis that published literature with a high level of evidence does not support the assertion that subarachnoid hemorrhage (SAH) causes cerebral vasospasm, which in turn causes cerebral infarction and poor outcome after aneurysmal SAH. The medical literature on SAH was searched in MEDLINE. The author's personal files of all published literature on SAH were reviewed. References cited in Cochrane reviews as well as the published papers that were reviewed were also retrieved.

There is no question that SAH causes what the authors have chosen to call “angiographic vasospasm.” However, the incidence and severity of vasospasm in recent series of patients is not well defined. There is reasonable evidence that vasospasm causes infarction, but again, accurate data on how severe and how diffuse vasospasm has to be to cause infarction and how often vasospasm is the primary cause of infarction are not available. There are good data on the incidence of cerebral infarction after SAH, and these data indicate that it is highly associated with poor outcome. The link between angiographic vasospasm and poor outcome is particularly poorly described in terms of what would be considered data of a high level of evidence.

The question as to whether there is a clear pathway from SAH to vasospasm to cerebral infarction to poor outcome seems so obvious to neurosurgeons as to make it one not worth asking. Nevertheless, the obvious is not always true or accurate, so it is important to note that published literature only weakly supports the causative association of vasospasm with infarction and poor outcome after SAH. It behooves neurosurgeons to document this seemingly straightforward pathway with high-quality evidence acceptable to the proponents of evidence-based medicine.

Safety of heparinization for cerebral aneurysm coiling soon after external ventriculostomy drain placement

OBJECTIVE

Our practice has been to heparinize patients for cerebral aneurysm coiling even after recent external ventriculostomy drain (EVD) placement. The current medical literature cites a 12.5% symptomatic hemorrhage rate with heparinization after recent EVD placement. We reviewed our experience to determine our level of safety with this practice.

METHODS

A search of our prospectively collected computerized aneurysm database revealed that from February 1998 to February 2004, 356 aneurysms were coiled, of which 119 patients had had recent EVD placement before coiling. During the same time period, 251 subarachnoid hemorrhage patients underwent EVD placement without coiling or heparinization. We reviewed the head computed tomographic scan reports and medical records to determine the incidence of EVD-related hemorrhage in heparinized patients compared with nonheparinized patients.

RESULTS

There was only 1 patient in the heparinized group who had a symptomatic EVD-related hemorrhage attributable to heparinization (0.8%) and 11 patients with asymptomatic EVD-related hemorrhage (9.2%). Among the nonheparinized patients, there were 3 patients who had symptomatic EVD-related hemorrhages (1.2%) and 22 patients with asymptomatic EVD-related hemorrhages (8.8%) (P = not significant for both symptomatic and asymptomatic EVD-related hemorrhages). The time interval between EVD placement and heparinization in the heparinized patient with symptomatic EVD-related hemorrhage was 0.5 day; the mean time interval in the heparinized patients with asymptomatic EVD-related hemorrhage was 0.8 day; and in the heparinized patients with no hemorrhage, it was 0.8 day. The peak activated prothrombin time of the heparinized patient with symptomatic EVD-related hemorrhage was >150 seconds, the mean peak activated prothrombin time of the heparinized patients with asymptomatic EVD-related hemorrhage was 73.1 seconds, and that of the heparinized patients with no hemorrhage was 90.3 seconds.

CONCLUSION

Heparinization for cerebral aneurysm coiling can be safely performed even after EVD placement within 24 hours, particularly if the activated prothrombin time is kept strictly controlled.

Management of cerebral vasospasm

Cerebral vasospasm is delayed narrowing of the large arteries of the circle of Willis occurring 4 to 14 days after aneurysmal subarachnoid hemorrhage (SAH). It is but one cause of delayed deterioration after SAH but, in general, is the most important potentially treatable cause of morbidity and mortality after SAH. Development of vasospasm is best predicted by the volume, location, persistence and density of subarachnoid clot early after SAH. Diagnosis is made by catheter angiography or, with less accuracy, by computed tomographic angiography, transcranial Doppler ultrasound or other methods. Treatment remains problematic because it is expensive, time-consuming, associated with substantial risk and largely ineffective. Treatment includes optimization of factors that affect cerebral blood flow and metabolism, systemic administration of nimodipine, hemodynamic therapy and pharmacologic and mechanical angioplasty.

Endovascular treatment of cerebral vasospasm: transluminal balloon angioplasty, intra-arterial papaverine, and intra-arterial nicardipine

Cerebral vasospasm is still one of the leading causes of morbidity and mortality from subarachnoid hemorrhage. Vasospasm refractory to medical management can be treated with endovascular therapies, such as transluminal balloon angioplasty or infusion of intra-arterial vasodilating agents. In our review of clinical series reported in the English language literature, transluminal balloon angioplasty produced clinical improvement in 62% of patients, significantly improved mean transcranial Doppler (TCD) velocities(P <.05), significantly improved cerebral blood flow (CBF) in 85% of patients as studied by (133)Xenon techniques and serial single photon emission computerized tomography,and was associated with 5.0% complications and 1.1% vessel rupture. Intra-arterial papaverine therapy produced clinical improvement in 43% of patients but only transiently,requiring multiple treatment sessions (1.7 treatments per patient); significantly improved mean TCD velocities (P <.01) but only for less than 48 hours; improved CBF in 60% of patients but only for less than 12 hours; and was associated with increases in intracranial pressure and 9.9% complications. Intra-arterial nicardipine therapy produced clinical improvement in 42% of patients, significantly improved mean TCD velocities (P <.001) for 4 days, and was associated with no complications in our small series. We have adopted a treatment protocol at our institution of transluminal balloon angioplasty and intra-arterial nicardipine therapy as the endovascular treatments for medically refractory cerebral vasospasm.

Endovascular Coiling for Cerebral Aneurysms

Aneurysmal subarachnoid hemorrhage is an increasing problem in the United States, affecting approximately 30,000 people every year. Despite advances in the neurosurgical field, approximately 50% of patients die within the first month after hemorrhage. Traditionally, craniotomy with aneurysmal clipping has been employed to manage these patients, but endovascular embolization is moving to the forefront of treatment, particularly for high grade (IV to V) aneurysms. Patient selection is often based on age, aneurysm size, location, characteristics and presentation, and patient hemodynamics. Postprocedure management relies on skilled observers to determine those potential complications that may occur, including vasospasm, rupture, bleeding, or vessel occlusion. Advanced practice nurses have an obligation to be aware not only of the procedure and its management, but also of the potential complications and ongoing care of the patients and families as well.

Anesthesia for neuroradiology

PURPOSE OF REVIEW

The role of anesthesia outside the operating room is rapidly expanding and evolving alongside with the advances in interventional neuroradiology. Increasingly complex diagnostic and therapeutic neuroradiological procedures are being performed on sicker patients. This review provides an overview of the principles of anesthetic management and summarizes recent advances in interventional neuroradiology.

RECENT FINDINGS

There are many new areas of development in interventional neuroradiology, but each also brings with it controversy. Use of newer agents for anesthesia and for anticoagulation may change the intraoperative management of patients. The role of neurophysiological monitoring during endovascular procedures is still to be validated. The optimal mode of treating cerebral aneurysms is still being debated. There has been increasing interest in and evidence of the efficacy of carotid artery stenting in the treatment of carotid artery disease. The utility of intraoperative magnetic resonance imaging in neurosurgery is expanding rapidly.

SUMMARY

Providing anesthesia in the interventional neuroradiology suite continues to be a challenge to the anesthesiologist. Understanding the anesthetic constraints and complexities and keeping abreast of the current developments in neuroradiology are crucial in ensuring the maximal benefits to and safety of patients.

Heparin-induced Thrombocytopenia Type II in Subarachnoid Hemorrhage Patients: Incidence and Complications

OBJECTIVE:

Heparin-induced thrombocytopenia Type II (HIT II) is the autoimmune-mediated severe form of the disease characterized by a significant reduction in platelets, and it carries a high risk of “paradoxical” serious thrombotic complications. Although HIT II has been studied in several different patient populations, the incidence of HIT II and the rate of thrombotic complications have never been reported in a neurosurgical patient population. Subarachnoid hemorrhage (SAH) patients, among neurosurgical patient populations, have a high exposure to heparin because they are in critical care units and have indwelling vascular catheters. In addition, the increase in neuroendovascular procedures with the associated use of heparinization will increase the exposure of SAH patients to heparin.

METHODS:

During a 3.5-year period (January 2000–June 2003), 389 consecutive SAH patients were treated at our center. We retrospectively reviewed their laboratory data and medical records and used accepted clinical criteria for the diagnosis of HIT II to determine the incidence of HIT II, thrombotic complications, management, and outcome.

RESULTS:

Fifty-nine patients (15%) met the clinical diagnostic criteria for HIT II. The average platelet count nadir in the HIT II patients was 68,600 ± 25,300/μl (mean ± standard deviation). Female patients and patients with Fisher Grade 3 were more likely to develop HIT II (P &lt; 0.01). Thirty-six patients (61%) underwent a neuroendovascular procedure. The rate of systemic thrombotic complications in the HIT II patients was 37 versus 7% in SAH patients without HIT II (P &lt; 0.001), and the rate of new hypodensities on head computed tomographic scans was 66% in the HIT II patients versus 40% in the SAH patients without HIT II (P &lt; 0.001). Clinical outcomes were worse in the HIT II patients. The outcome was favorable for 38% in the HIT II patients versus 52% in all SAH patients (P &lt; 0.05), and deaths were more common (29%) in the HIT II patients than in all SAH patients (12%, P &lt; 0.001).

CONCLUSION:

The incidence of HIT II in SAH patients at a single center was 15%. The SAH patients with HIT II had significantly higher rates of thrombotic complications, new hypodensities on head computed tomographic scans, more deaths, and significantly less favorable outcomes. This is the first report of the incidence of HIT II in a neurosurgical patient population.