The International Cooperative Study on the Timing of Aneurysm Surgery. Part 2: Surgical results

Lower head of the bed position does not change blood flow velocity in subarachnoid hemorrhage

BACKGROUND

Transcranial Doppler (TCD) is commonly used to monitor for vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH). Changes in head of the bed (HOB) positions alter blood flow velocities measured by TCD in patients with ischemic stroke. However, the effects of HOB position on the velocities of the cerebral blood flow have not been studied in aSAH patients.

METHODS

We measured the middle cerebral artery (MCA) mean flow velocity (MFV) in consecutive patients with aSAH using TCD with the HOB positioned at 30°-45° and then at 0°-15°. We also collected information on intracranial pressure (ICP) and arterial blood pressure at the time of the TCD studies. Our aim was to determine if changes in HOB position affect MFV in patients with aSAH.

RESULTS

We analyzed 35 TCD studies in 19 patients (mean age 53 ± 13 years). Thirteen studies (37%) showed ultrasonographic evidence of vasospasm. Systolic arterial blood pressure, heart rate, and ICP were not significantly affected by HOB position. The mean MFV of the MCA was 101.0 ± 47.3 cm/s with 0°-15° HOB position versus 100.1 ± 46.8 cm/s with 30°-45° HOB position (P = 0.77 on paired t test). HOB position did not have a significant influence on MFV regardless of the presence of vasospasm.

CONCLUSION

HOB position did not significantly affect MFV in our patients with aSAH.

Variation of patient characteristics, management, and outcome with timing of surgery for aneurysmal subarachnoid hemorrhage

OBJECT

The past 30 years have seen a shift in the timing of surgery for aneurysmal subarachnoid hemorrhage (SAH). Earlier practices of delayed surgery that were intended to avoid less favorable surgical conditions have been replaced by a trend toward early surgery to minimize the risks associated with rebleeding and vasospasm. Yet, a consensus as to the optimal timing of surgery has not been reached. The authors hypothesized that earlier surgery, performed using contemporary neurosurgical and neuroanesthesia techniques, would be associated with better outcomes when using contemporary management practices, and sought to define the optimal time interval between SAH and surgery.

METHODS

Data collected as part of the Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST) were analyzed to investigate the relationship between timing of surgery and outcome at 3 months post-SAH. The IHAST enrolled 1001 patients in 30 neurosurgical centers between February 2000 and April 2003. All patients had a radiographically confirmed SAH, were World Federation of Neurosurgical Societies Grades I-III at the time of surgery, and underwent surgical clipping of the presumed culprit aneurysm within 14 days of the date of hemorrhage. Patients were seen at 90-day follow-up visits. The primary outcome variable was a Glasgow Outcome Scale score of 1 (good outcome). Intergroup differences in baseline, intraoperative, and postoperative variables were compared using the Fisher exact tests. Variables reported as means were compared with ANOVA. Multiple logistic regression was used for multivariate analysis, adjusting for covariates. A p value of less than 0.05 was considered to be significant.

RESULTS

Patients who underwent surgery on Days 1 or 2 (early) or Days 7-14 (late) (Day 0 = date of SAH) fared better than patients who underwent surgery on Days 3-6 (intermediate). Specifically, the worst outcomes were observed in patients who underwent surgery on Days 3 and 4. Patients who had hydrocephalus or Fisher Grade 3 or 4 on admission head CT scans had better outcomes with early surgery than with intermediate or late surgery.

CONCLUSIONS

Early surgery, in good-grade patients within 48 hours of SAH, is associated with better outcomes than surgery performed in the 3- to 6-day posthemorrhage interval. Surgical treatment for aneurysmal SAH may be more hazardous during the 3- to 6-day interval, but this should be weighed against the risk of rebleeding.

Treatment of subarachnoid hemorrhage with human albumin: ALISAH study. Rationale and design

The primary objective of this prospective dose-finding pilot study is to demonstrate the tolerability and safety of four dosages of 25% human albumin in patients with subarachnoid hemorrhage (SAH). For each dosage group, the study will enroll 20 patients who meet the eligibility criteria. The enrolled patients will undergo follow-up for 90 days post-treatment. The primary tolerability hypothesis is that intravenous 25% human albumin can be given without precipitating treatment related serious adverse events beyond expectations. The study will determine the maximum tolerated dosage of 25% human albumin therapy based on the rate of treatment related serious adverse events during treatment: severe or life-threatening heart failure. The secondary objectives are to obtain preliminary estimates of the albumin treatment effect using the incidence of neurological deterioration within 15 days after symptom onset. In addition, the incidence of rebleeding, hydrocephalus, seizures, delayed cerebral ischemia and the incidence of vasospasm (both symptomatic and by transcranial Doppler ultrasound criteria) within 15 days after symptom onset will be evaluated. Furthermore, the serum osmolality and serum albumin concentrations, serum magnesium concentration, blood pressure and heart rate within 15 days of symptom onset will also be observed. The Glasgow Outcome Scale, Barthel Index, modified Rankin Scale, NIH Stroke Scale, and Stroke Impact Scale will be performed 3 months after the onset of symptoms to assess residual neurological deficits.

Evaluation of the prognostic indicators of giant intracranial aneurysms

The indicators of poor outcome in giant intracranial aneurysms have been the subject of several studies in the literature. We conducted a retrospective analysis to evaluate the predictors of poor outcome in giant intracranial aneurysms. We studied consecutive cases with aneurysms admitted over a 9-year period in our institution. All the aneurysms were treated with clipping. Patient demographics, clinical profile, and aneurysm characteristics were evaluated in a multivariate analysis as probable indicators of Glasgow Outcome Scale (GOS) score. The outcome of the aneurysms (GOS score) was compared with the remaining non-giant aneurysms. A total of 41 giant and 348 non-giant aneurysms were identified in our series. In the multivariate analysis, the indicators of poor outcome were identified as poor clinical grade (p < 0.0004), intraoperative rupture (p < 0.007), and posterior circulation of the aneurysms (p < 0.01). Non-giant aneurysms had a better outcome compared with the giant aneurysms (p < 0.01). Giant aneurysms impose a relatively higher risk of morbidity and mortality to the patients. The predictors of the postsurgical outcome of the giant aneurysms include the clinical condition of the patient, location of the aneurysm, and intraoperative rupture.

Brain energy metabolism in patients with spontaneous subarachnoid hemorrhage and global cerebral edema

BACKGROUND

Previous studies of spontaneous subarachnoid hemorrhage (SAH) have shown that global cerebral edema on the first computed tomography scan is associated with a more severe initial injury and is an independent predictor of poor outcome. Effects of secondary ischemic events also influence outcome after SAH.

OBJECTIVE

This study demonstrates that early global edema is related to markers of an increased cerebral energy metabolism as measured with intracerebral microdialysis, which could increase vulnerability to adverse events.

METHODS

Fifty-two patients with microdialysis monitoring after spontaneous SAH were stratified according to the occurrence of global cerebral edema on the first computed tomography scan taken a median of 2 hours after the initial bleed. Microdialysis levels of glucose, lactate, and pyruvate were compared between the global edema (n = 31) and no global edema (n = 21) groups. Clinical outcome was assessed with the Glasgow Outcome Scale score at >/= 6 months.

RESULTS

Patients with global edema showed significantly elevated lactate and pyruvate levels 70 to 79 hours after SAH and marginally significantly higher levels of lactate 60 to 69 hours and 80 to 89 hours after SAH. There was a trend toward worse outcome in the edema group.

CONCLUSION

Patients with global cerebral edema have higher interstitial levels of lactate and pyruvate. The edema group may have developed a cerebral hypermetabolism to meet the increased energy demand in the recovery phase after SAH. This stress would make the brain more vulnerable to secondary insults, increasing the likelihood of energy failure.

Objective evaluation of the treatment methods of intracranial aneurysm surgery

OBJECTIVE

this study evaluated the clinical value of craniotomy and intravascular embotherapy in the treatment of intracranial aneurysms.

METHODS

The clinical data of 126 cases of intracranial aneurysms from July 2008 to July 2009 was analyzed retrospectively, 86 cases of all were clipped and other 40 cases were coiled.

RESULTS

in 86 cases with craniotomy (according to Hunt-Hess classification, 71 cases belong to grade I-III and 15 cases belong to grade IV-V), 1 case died, 3 cases recovered with serious nervous system symptoms, 9 cases recovered with Mild neurological symptoms, and the remaining 73 cases recovered with normal life and work. In 40 cases with intravascular embotherapy (according to Hunt-Hess classification, 33 cases belong to grade I-III and 7 cases belong to grade IV-V), 2 cases recovered with serious nervous system symptoms, 5 cases recovered with mild neurological symptoms, the remaining 33 cases recovered with normal life and work; no death case.

CONCLUSIONS

the situation is different in patients according to aneurysm size, shape, and location; if treatment for intracranial aneurysms is to achieve a satisfactory effect, two treatments must complement each other.

Association of hemodynamic characteristics and cerebral aneurysm rupture

BACKGROUND AND PURPOSE

Hemodynamic factors are thought to play an important role in the initiation, growth, and rupture of cerebral aneurysms. This report describes a study of the associations between qualitative intra-aneurysmal hemodynamics and the rupture of cerebral aneurysms.

MATERIALS AND METHODS

Two hundred ten consecutive aneurysms were analyzed by using patient-specific CFD simulations under pulsatile flow conditions. The aneurysms were classified into categories by 2 blinded observers, depending on the complexity and stability of the flow pattern, size of the impingement region, and inflow concentration. A statistical analysis was then performed with respect to the history of previous rupture. Interobserver variability analysis was performed.

RESULTS

Ruptured aneurysms were more likely to have complex flow patterns (83%, P < .001), stable flow patterns (75%, P = .0018), concentrated inflow (66%, P = <.0001), and small impingement regions (76%, P = .0006) compared with unruptured aneurysms. Interobserver variability analyses indicated that all the classifications performed were in very good agreement-that is, well within the 95% CI.

CONCLUSIONS

A qualitative hemodynamic analysis of cerebral aneurysms by using image-based patient-specific geometries has shown that concentrated inflow jets, small impingement regions, complex flow patterns, and unstable flow patterns are correlated with a clinical history of prior aneurysm rupture. These qualitative measures provide a starting point for more sophisticated quantitative analysis aimed at assigning aneurysm risk of future rupture. These analyses highlight the potential for CFD to play an important role in the clinical determination of aneurysm risks.

Inflammation and cerebral vasospasm after subarachnoid hemorrhage

Morbidity and mortality of patients with aneurysmal subarachnoid hemorrhage (aSAH) is significantly related to the development of chronic cerebral vasospasm. Despite extensive clinical and experimental research, the pathophysiology of the events that result in delayed arterial spasm is not fully understood. A review of the published literature on cerebral vasospasm that included but was not limited to all PubMed citations from 1951 to the present was performed. The findings suggest that leukocyte-endothelial cell interactions play a significant role in the pathophysiology of cerebral vasospasm and explain the clinical variability and time course of the disease. Experimental therapeutic targeting of the inflammatory response when timed correctly can prevent vasospasm, and supplementation of endothelial relaxation by nitric oxide-related therapies and other approaches could result in reversal of the arterial narrowing and improved outcomes in patients with aSAH.

Surgical management of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a common and often devastating condition that requires prompt neurosurgical evaluation and intervention. Modern management of aSAH involves a multidisciplinary team of subspecialists, including vascular neurosurgeons, neurocritical care specialists and, frequently, neurointerventional radiologists. This team is responsible for stabilizing the patient on presentation, diagnosing the offending ruptured aneurysm, securing the aneurysm, and managing the patient through a typically prolonged and complicated hospital course. Surgical intervention has remained a definitive treatment for ruptured cerebral aneurysms since the early 1900s. Over the subsequent decades, many innovations in microsurgical technique, adjuvant maneuvers, and intraoperative and perioperative medical therapies have advanced the care of patients with aSAH. This report focuses on the modern surgical management of patients with aSAH. Following a brief historical perspective on the origin of aneurysm surgery, the topics discussed include the timing of surgical intervention after aSAH, commonly used surgical approaches and craniotomies, fenestration of the lamina terminalis, intraoperative neurophysiological monitoring, intraoperative digital subtraction and fluorescent angiography, temporary clipping, deep hypothermic cardiopulmonary bypass, management of acute hydrocephalus, cerebral revascularization, and novel clip configurations and microsurgical techniques. Many of the topics highlighted in this report represent some of the more debated techniques in vascular neurosurgery. The popularity of such techniques is constantly evolving as new studies are performed and data about their utility become available.

Epidemiology of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a form of hemorrhagic stroke that affects up to 30,000 individuals per year in the United States. The incidence of aSAH has been shown to be associated with numerous nonmodifiable (age, gender, ethnicity, family history, aneurysm location, size) and modifiable (hypertension, body mass index, tobacco and illicit drug use) risk factors. Although early repair of ruptured aneurysms and aggressive postoperative management has improved overall outcomes, it remains a devastating disease, with mortality approaching 50% and less than 60% of survivors returning to functional independence. As treatment modalities change and the percentage of minority and elderly populations increase, it is critical to maintain an up-to-date understanding of the epidemiology of SAH.

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.

Stent-assisted coil embolization for the proximal middle cerebral artery fusiform aneurysm

Middle cerebral artery (MCA) fusiform aneurysms often have an unfavorable geometry that may limit surgical or endovascular treatment. Herein, we present a case of a fusiform aneurysm of the proximal MCA, which was successfully treated using stent-assisted coil embolization. A 42-year-old man presented with repeated headache and syncope. Five years earlier, a right MCA aneurysm had been treated by aneurismal wrapping. Magnetic resonance images (MRI) revealed a partially-thrombosed proximal MCA aneurysm at the right perisylvian region. Digital subtraction angiography (DSA) revealed a multilobulated fusiform-shaped aneurysm. The patient underwent stent-assisted coil embolization under general anesthesia and symptoms resolved postoperatively. A three-month follow-up angiography revealed no recanalization of the aneurysm and indicated tolerable blood flow through the right MCA, as compared to the preoperative angiography. We suggest that in selected patients, stent-assisted coil embolization of proximal MCA fusiform aneurysms can be an effective treatment modality.

Endovascular management of intracranial aneurysms

Data from our clinical series and others supports the idea that endovascular coil embolization is a reliable form of treatment for both ruptured and unruptured cerebral aneurysms. This form of treatment appears from preliminary data to be protective against subarachnoid hemorrhage. Although not likely to replace open surgery, the continued advancements in technology and supportive clinical data will allow endovascular therapy to become a more durable mode of treatment.

Comparative Study Evaluating the In Vivo Characteristics of Ruptured and Unruptured Aneurysms Using serial Digital Subtraction Angiography

Over the past decade preventive endovascular treatment is increasingly being considered for intracranial aneurysms irrespective of whether ruptured or unruptured. Few studies have dealt with in-vivo characteristics of intracranial aneurysms. We compare the angiographic morphology of ruptured and unruptured intracranial aneurysms using short interval serial DSA. 37 patients with intracranial aneurysms and who underwent at least two digital subtraction angiograms were included in the study. Based on the clinical presentation there were two subgroups of patients, Group A patients presenting acutely with Sub arachnoid haemorrhage (SAH) and Group B patients who had no clinical or imaging features suggestive of bleed. Clinical and serial angiographic data were correlated. Aneurysms in Group A (1.04 mm(3)) were significantly (p=0.010) smaller than in Group B (4.53 mm(3)). Aneurysms in group A showed increase in size and those in Group B showed a decrease in size (p=0.019). Hypertensive patients in both the groups showed a tendency for a decrease in the size of the aneurysms. Aneurysms having stasis at the time of initial angiogram had significantly reduced in size on follow up (p=0.013) at a faster rate (p=0.017). Presence of spasm in adjacent vessels was associated with increase in size of aneurysm on follow up in both Groups. There are significant differences between a ruptured aneurysm and an unruptured one. Ruptured aneurysms are small and show rapid increase in size. The presence of spasm increased the size of the aneurysm in the post rupture period and anti hypertensive medication and stasis were associated with decrease in size.

Rerupture of intracranial aneurysms during cerebral angiography

Three cases of re-rupture of intracranial aneurysms during cerebral angiography (RIADCA) between June and September, 2001 are reported. All cases underwent emergency craniotomy and aneurysm clipping. The subarachnoid blood and the extravasating contrast medium were removed intraoperatively as completely as possible. There was no mortality in this series. The incidence, timing, sex, age, inducing factors, risk factors, prevention measures and prognosis are discussed and reviewed in conjunction with the literature.

Intensive care management of acute stroke: general management

For a long time, patients with severe stroke were facing therapeutic nihilism of the attending physicians. Implementation of do-not-resuscitate-orders may have lead to self-fulfilling prophecies and to a pessimistic overestimation of prognosis of severe stroke syndromes. However, there have been great advances in intensive care management of acute stroke patients and it has been shown that treatment on a specialised neurological intensive care unit improves outcome. In this review, we will present a summary of the current state-of-the-art intensive care management of acute stroke patients. After presenting an overview on general management of stroke intensive care patients, special aspects of neurological intensive care of acute large middle cerebral artery stroke, intracerebral haemorrhage and subarachnoid haemorrhage will be discussed. In part II of the review, surgical management options for acute stroke will be discussed in detail.

Patients with supratentorial aneurysmal subarachnoid hemorrhage during the intermediate period: waiting or actively treating

Perhaps the most difficult practical decision for neurosurgeons these days is whether to secure aneurysms during the intermediate period (4-10 days) after aneurysmal subarachnoid hemorrhage (SAH). We retrospectively reviewed a series of 115 patients with a Hunt-Hess grade I-III upon admission who were admitted 4-10 days after initial supratentorial aneurysmal SAH. Patients who underwent active treatment in the intermediate period were assigned to the intermediate group (n = 49) while those who accepted delayed obliteration of a ruptured aneurysm (11-30 days) were assigned to the late group (n = 66). The demographic characteristics, size and site of aneurysms, and clinical conditions were well balanced in the two groups. There was no difference in outcome between the two groups according to the Glasgow Outcome Scale (GOS) at discharge or a six-month follow-up. Rebleeding before aneurysms obliteration was the leading factor resulting in poor outcome. In conclusion, for patients with supratentorial aneurysmal SAH who were in good clinical condition upon admission, active treatment during the intermediate period offered a good chance of a favorable outcome. An even larger number of patients from randomized clinical trials might be necessary to draw more reliable conclusions.

Shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage: incidence, predictors, and revision rates. Clinical article

OBJECT

Chronic shunt-dependent hydrocephalus is a recognized complication of aneurysmal subarachnoid hemorrhage. While its incidence and risk factors have been well described, the long-term performance of shunts in this setting has not been not widely reported.

METHODS

Using administrative databases, the authors derived a retrospective cohort of patients undergoing treatment of a ruptured aneurysm in Ontario, Canada, between 1995 and 2005. The authors determined the incidence of shunt-dependent hydrocephalus and analyzed putative risk factors. Mortality rates and indicators of morbidity were recorded. Patients were followed up for the occurrence of shunt failure over time.

RESULTS

Of 3120 patients in the cohort, 585 (18.75%) developed shunt-dependent hydrocephalus. On multivariate analysis, age, acute hydrocephalus, ventilation on admission, aneurysms in the posterior circulation and giant aneurysms were all significant predictors of shunt-dependent hydrocephalus. The mortality rate was not increased in patients with chronic hydrocephalus (hazard ratio 1.04, p = 0.63); however, indicators of morbidity were increased in these patients. Of the 585 patients with shunt-dependent hydrocephalus, only 173 (29.6%) underwent a subsequent revision procedure. Ninety-eight percent of these revisions were completed within 6 months. Subsequent revisions occurred more frequently. On multivariate analysis, significant predictors of shunt revision included aneurysm location in the posterior circulation and endovascular treatment of the initial ruptured aneurysm.

CONCLUSIONS

Shunt-dependent hydrocephalus affects a significant proportion of subarachnoid hemorrhage survivors, contributing to additional morbidity among these patients. Shunt failures occur less frequently in patients who underwent treatment for a ruptured aneurysm than with other forms of hydrocephalus. Most failures occur within 6 months, suggesting that shunt dependency may be transient in the majority of patients.

Endovascular treatment with bare platinum coils for middle cerebral artery aneurysms

Middle cerebral artery (MCA) aneurysms often have unfavorable anatomical characteristics preventing successful endovascular occlusion. We reviewed the outcomes of our series of endosaccular embolization of MCA aneurysms using bare platinum coils, angiographic images, and medical records. Immediate and follow-up angiographic results were categorized as complete occlusion, residual neck, and residual flow. Follow-up angiographic changes were categorized as unchanged, minor or major recurrence, and progressive thrombosis. Between December 2001 and August 2007, 112 patients with 113 MCA aneurysms underwent endovascular treatment, of whom 60 presented with subarachnoid hemorrhage (SAH) due to MCA aneurysm rupture. Immediate angiographic outcomes for 103 aneurysms revealed complete occlusion in 64, residual neck in 21, residual flow in 18, and failed embolization in 10. Follow-up angiography of 70 aneurysms demonstrated 41 unchanged, 10 minor recurrences, 12 major recurrences, 7 progressive thromboses, and no bleeding of coil embolized aneurysms. Outcomes of 58 SAH patients treated endovascularly revealed 45 good recovery and moderate disability, 10 severe disability or persistent vegetative state, and 3 deaths. Forty-four of the 45 patients with unruptured aneurysms treated endovascularly had no changes in their neurological status. One of 5 patients with complications had permanent morbidity. For patients with MCA aneurysms suitable for endovascular surgery, bare platinum coil embolization can be performed with acceptable low morbidity and mortality rates, with a lower risk of postprocedural aneurysmal bleeding.

Role of inflammation (leukocyte-endothelial cell interactions) in vasospasm after subarachnoid hemorrhage

BACKGROUND

Delayed vasospasm is the leading cause of morbidity and mortality after aneurysmal subarachnoid hemorrhage (aSAH). This phenomenon was first described more than 50 years ago, but only recently has the role of inflammation in this condition become better understood.

METHODS

The literature was reviewed for studies on delayed vasospasm and inflammation.

RESULTS

There is increasing evidence that inflammation and, more specifically, leukocyte-endothelial cell interactions play a critical role in the pathogenesis of vasospasm after aSAH, as well as in other conditions including meningitis and traumatic brain injury. Although earlier clinical observations and indirect experimental evidence suggested an association between inflammation and chronic vasospasm, recently direct molecular evidence demonstrates the central role of leukocyte-endothelial cell interactions in the development of chronic vasospasm. This evidence shows in both clinical and experimental studies that cell adhesion molecules (CAMs) are up-regulated in the perivasospasm period. Moreover, the use of monoclonal antibodies against these CAMs, as well as drugs that decrease the expression of CAMs, decreases vasospasm in experimental studies. It also appears that certain individuals are genetically predisposed to a severe inflammatory response after aSAH based on their haptoglobin genotype, which in turn predisposes them to develop clinically symptomatic vasospasm.

CONCLUSION

Based on this evidence, leukocyte-endothelial cell interactions appear to be the root cause of chronic vasospasm. This hypothesis predicts many surprising features of vasospasm and explains apparently unrelated phenomena observed in aSAH patients. Therapies aimed at preventing inflammation may prevent and/or reverse arterial narrowing in patients with aSAH and result in improved outcomes.

Risk of stroke with temporary arterial occlusion in patients undergoing craniotomy for cerebral aneurysm

OBJECTIVE

This study was performed to elucidate the technical and patient-specific risk factors for postoperative ischemia in patients undergoing temporary arterial occlusion (TAO) during the surgical repair of their aneurysms.

METHODS

Eighty-nine consecutive patients in whom TAO was performed during surgical repair of an aneurysm were retrospectively analyzed. The demographics of the patients were analyzed with respect to age, Hunt and Hess grade on admission, Fisher grade of hemorrhage, aneurysm characteristics, timing of surgery, duration of temporary occlusion, and number of temporary occlusive episodes. Outcome was analyzed at the 3-month follow-up, along with the occurrence of symptomatic and radiological stroke.

RESULTS

In overall, twenty-seven patients (29.3%) had radiologic ischemia attributable to TAO and fifteen patients (16.3%) had symptomatic ischemia attributable to TAO. Older age and poor clinical grade were associated with poor clinical outcome. There was a significantly higher rate of symptomatic ischemia in patients who underwent early surgery (p = 0.007). The incidence of ischemia was significantly higher in patients with TAO longer than 10 minutes (p = 0.01). In addition, patients who underwent repeated TAO, which allowed reperfusion, had a lower incidence of ischemia than those who underwent single TAO lasting for more than 10 minutes (p = 0.011).

CONCLUSION

Duration of occlusion is the only variable that needs to be considered when assessing the risk of postoperative ischemic complication in patients who undergo temporary vascular occlusion. Attention must be paid to the patient's age, grade of hemorrhage, and the timing of surgery. In addition, patients undergoing dissection when brief periods of temporary occlusion are performed may benefit more from intermittent reperfusion than continuous clip application. With careful planning, the use of TAO is a safe technique when used for periods of less than 10 minutes.

Endovascular treatment of middle cerebral artery aneurysms with detachable coils: angiographic and clinical outcomes in 115 consecutive patients

OBJECTIVE

Because of their anatomic configuration, middle cerebral artery (MCA) aneurysms are most often treated with surgical clipping. However, endovascular coil embolization of these aneurysms is an increasingly used alternative. We retrospectively reviewed the anatomic and clinical outcomes of patients with MCA aneurysms who underwent endovascular treatment at our institution.

METHODS

One hundred fifteen MCA aneurysms in 115 patients (mean age, 55.1 years) were treated by an endovascular technique from April 1990 to March 2007. Forty-eight patients (42%) presented with acute subarachnoid hemorrhage, and 67 patients (58%) had unruptured aneurysms. Fifty-three aneurysms (46%) were small with a small neck, 28 (24%) were small with a wide neck, 22 (19%) were large, and 12 (11%) were giant.

RESULTS

Angiographic results immediately after embolization showed complete occlusion in 53 aneurysms (46%), a neck remnant in 51 (44%), and incomplete occlusion in 3 (3%). Because of anatomic difficulties, we could not embolize 8 aneurysms (7%). Thirteen patients underwent combined treatment that included endovascular and extracranial-intracranial bypass surgery. Morbidity and mortality rates were 6.9% (8 patients) and 3% (3 patients), respectively. Procedure-related complications were encountered in 10 patients (9%). Seventy patients had long-term follow- up angiograms. Seven aneurysms (10%) were recanalized; all were large or giant. One partially embolized large aneurysm ruptured 13 months after embolization.

CONCLUSION

In this series, endovascular coil embolization of MCA aneurysms has morbidity and mortality rates comparable to those of conventional surgical clipping. Combined treatment of endovascular and bypass surgery can successfully treat large or giant complex fusiform MCA aneurysms.

Effect of country or continent of treatment on outcome after aneurysmal subarachnoid hemorrhage

Object

Prognostic factors for outcome after aneurysmal subarachnoid hemorrhage (SAH) include the clinical and pathological characteristics of the patient and hemorrhage as well as some aspects of treatment. Because treatment can vary between countries and continents, the authors used a large database of patients with SAH to determine the effect of the geographic location of treatment on outcome.

Methods

Data obtained in 3567 patients who were entered into randomized trials of tirilazad between 1991 and 1997 were analyzed. Patients underwent treatment in 162 neurosurgical centers in 21 countries in North America, Europe, Africa, and Australia. The dependent variable was clinical outcome assessed 3 months after SAH with the Glasgow Outcome Scale, which was analyzed as a 5-point variable and dichotomized into favorable (good recovery or moderate disability) and unfavorable (severe disability, vegetative state, or death) outcomes. The effect of country or continent of treatment on outcome was assessed using univariate and multivariate logistic regression and proportional odds modeling before and after adjusting for numerous other factors significantly associated with outcome.

Results

The authors constructed several multivariate analysis models and demonstrated that for almost every model, country was not a significant predictor of outcome (p > 0.05). There was variation in outcome between countries, but this was mostly due to differences in other admission characteristics that influence outcome such as age, clinical grade, and subarachnoid clot thickness. Because the number of patients entered from some countries was small, countries were grouped, and the data were analyzed by continent. This grouping gave more stable estimates and created an appropriate model for both logistic and proportional odds models and again showed that continent had no significant effect on outcome.

Conclusions

Despite the variations in treatment that undoubtedly exist between countries and continents, the location of treatment had minimal effect on outcome. Outcome was influenced mostly by clinical characteristics on admission such as neurological grade, patient age, and amount of SAH.

Gravitational valves in supine patients with ventriculo-peritoneal shunts

BACKGROUND

In the subgroup of bedridden hydrocephalic patients with ventriculo-peritoneal shunts and gravitational valves, we occasionally observed persisting hydrocephalic complaints even when mechanical or infection-related obstruction was excluded.

METHODS

To investigate the cause of these hydrocephalic symptoms, in vitro and in vivo analyses were used to determine valve opening, intra-abdominal and hydrostatic pressure of an Aesculap-Miethke 10/40 cm H2O gravitational valve at different angles of upper body and head inclination.

FINDINGS

Since hydrostatic pressure is lacking, the resulting intra-ventricular pressures are shown to peak up to 27 cm H2O in supine patients with head, but not upper body inclined.

CONCLUSIONS

We conclude that in the subgroup of bedridden patients with ventriculo-peritoneal shunts and gravitational valves, upright posture is a prerequisite for proper cerebrospinal fluid drainage.

Endothelial nitric oxide synthase tagging single nucleotide polymorphisms and recovery from aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a hemorrhagic stroke subtype with a poor recovery profile. Cerebral vasospasm (CV), a narrowing of the cerebral vasculature, significantly contributes to the poor recovery profile. Variation in the endothelial nitric oxide (NO) synthase (eNOS) gene has been implicated in CV and outcome after SAH. The purpose of this project was to explore the potential association between three eNOS tagging single nucleotide polymorphisms (SNPs) and recovery from SAH. We included 195 participants with a diagnosis of SAH and DNA and 6-month outcome data available but without preexisting neurologic disease/deficit. Genotyping was performed using an ABI Prism 7000 Sequence Detection System and TaqMan assays. CV was verified by cerebral angiogram independently read by a neurosurgeon on 118 participants. Modified Rankin Scores (MRS) and Glasgow Outcome Scale (GOS) scores were collected 6 months posthemorrhage. Data were analyzed using descriptive statistics, analysis of variance (ANOVA) and chi-square analysis as appropriate. The sample was primarily female (n=147; 75.4%) and White (n=178; 91.3%) with a mean age of 54.6 years. Of the participants with CV data, 56 (47.5%) developed CV within 14 days of SAH. None of the SNPs individually were associated with CV presence; however, a combination of the three variant SNPs was significantly associated with CV (p=.017). Only one SNP (rs1799983, variant allele) was associated with worse 6-month GOS scores (p<.001) and MRS (p<.001). These data indicate that the eNOS gene plays a role in the response to SAH, which may be explained by an influence on CV.

Defining vasospasm after subarachnoid hemorrhage: what is the most clinically relevant definition?

BACKGROUND AND PURPOSE

Vasospasm is an important complication of subarachnoid hemorrhage, but is variably defined in the literature.

METHODS

We studied 580 patients with subarachnoid hemorrhage and identified those with: (1) symptomatic vasospasm, defined as clinical deterioration deemed secondary to vasospasm after other causes were eliminated; (2) delayed cerebral ischemia (DCI), defined as symptomatic vasospasm, or infarction on CT attributable to vasospasm; (3) angiographic spasm, as seen on digital subtraction angiography; and (4) transcranial Doppler (TCD) spasm, defined as any mean flow velocity >120 cm/sec. Logistic regression analysis was performed to test the association of each definition of vasospasm with various hospital complications, and 3-month quality of life (sickness impact profile), cognitive status (telephone interview of cognitive status), instrumental activities of daily living (Lawton score), and death or severe disability at 3 months (modified Rankin scale score 4-6), after adjustment for covariates.

RESULTS

Symptomatic vasospasm occurred in 16%, DCI in 21%, angiographic vasospasm in 31%, and TCD spasm in 45% of patients. DCI was statistically associated with more hospital complications (N=7; all P<0.05) than symptomatic spasm (N=4), angiographic spasm (N=1), or TCD vasospasm (N=1). Angiographic and TCD vasospasm were not related to any aspect of clinical outcome. Both symptomatic vasospasm and DCI were related to reduced instrumental activities of daily living, cognitive impairment, and poor quality of life (all P<0.05). However, only DCI was associated with death or severe disability at 3 months (adjusted OR, 2.2; 95% CI, 1.2-3.9; P=0.007).

CONCLUSIONS

DCI is a more clinically meaningful definition than either symptomatic deterioration alone or the presence of arterial spasm by angiography or TCD.

Surgical management of intracranial aneurysms in the endovascular era : review article

The advent of endovascular therapy for intracranial aneurysms and the rapid advances in that field have supplanted microsurgical treatment for many intracranial aneurysms. Applying current outcome data and other parameters, nuances of selecting the modality of treatment for intracranial aneurysms are reviewed. Patient factors, such a age, co-morbidities, vasospasm and other medical conditions, are addressed. A custom-tailored multimodality treatment paradigm for the management of ruptured and unruptured aneurysms will maximize the favorable results seen in this difficult patient population.

RESUSCITATION AND CRITICAL CARE OF POOR-GRADE SUBARACHNOID HEMORRHAGE

AS OUTCOMES HAVE improved for patients with aneurysmal subarachnoid hemorrhage, most mortality and morbidity that occur today are the result of severe diffuse brain injury in poor-grade patients. The premise of this review is that aggressive emergency cardiopulmonary and neurological resuscitation, coupled with early aneurysm repair and advanced multimodality monitoring in a specialized neurocritical care unit, offers the best approach for achieving further improvements in subarachnoid hemorrhage outcomes. Emergency care should focus on control of elevated intracranial pressure, optimization of cerebral perfusion and oxygenation, and medical and surgical therapy to prevent rebleeding. In the postoperative period, advanced monitoring techniques such as continuous electroencephalography, brain tissue oxygen monitoring, and microdialysis can detect harmful secondary insults, and may eventually be used as end points for goal-directed therapy, with the aim of creating an optimal physiological environment for the comatose injured brain. As part of this paradigm shift, it is essential that aggressive surgical and medical support be linked to compassionate end-of-life care. As neurosurgeons become confident that comfort care can be implemented in a straightforward fashion after a failed trial of early maximal intervention, the usual justification for withholding treatment (survival with neurological devastation) becomes less relevant, and lives may be saved as more patients recover beyond expectations.

Reporting standards for endovascular repair of saccular intracranial cerebral aneurysms

BACKGROUND AND PURPOSE

The goal of this article is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting on the radiological evaluation and endovascular treatment of intracranial, cerebral aneurysms. These criteria can be used to design clinical trials, to provide uniformity of definitions for appropriate selection and stratification of patients, and to allow analysis and meta-analysis of reported data.

METHODS

This article was written under the auspices of the Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1991 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data about the assessment and endovascular treatment of cerebral aneurysms useful as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This article offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of cerebral aneurysms. Included in this guidance article are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSIONS

The evaluation and treatment of brain aneurysms often involve multiple medical specialties. Recent reviews by the American Heart Association have surveyed the medical literature to develop guidelines for the clinical management of ruptured and unruptured cerebral aneurysms. Despite efforts to synthesize existing knowledge on cerebral aneurysm evaluation and treatment, significant inconsistencies remain in nomenclature and definition for research and reporting purposes. These operational definitions were selected by consensus of a multidisciplinary writing group to provide consistency for reporting on imaging in clinical trials and observational studies involving cerebral aneurysms. These definitions should help different groups to publish results that are directly comparable.