The value of computerized tomography in aneurysmal subarachnoid hemorrhage. The concept of the CT score

Subarachnoid Blood Clearance and Aneurysmal Subarachnoid Hemorrhage Outcomes: A Retrospective Review

BACKGROUND

Delayed cerebral ischemia (DCI) continues to be a significant contributor to morbidity and mortality following aneurysmal subarachnoid hemorrhage (aSAH). Subarachnoid blood and its degradation products have been implicated in DCI, and faster blood clearance has been hypothesized to confer better outcomes. This study evaluates the relationship between blood volume and its clearance on DCI (primary outcome) and location at 30 days (secondary outcome) after aSAH.

METHODS

This is a retrospective review of adult patients presenting with aSAH. Hijdra sum scores (HSS) were assessed independently for each computed tomography (CT) scan of patients with available scans on post-bleed days 0-1 and 2-10. This cohort was used to evaluate the course of subarachnoid blood clearance (group 1). A subset of patients in the first cohort with available CT scans on both post-bleed days 0-1 and post-bleed days 3-4 composed the second cohort (group 2). This group was used to evaluate the association between initial subarachnoid blood (measured via HSS post-bleed days 0-1) and its clearance (measured via percentage reduction [HSS %Reduction] and absolute reduction [HSS-Abs-Reduction] in HSS between days 0-1 and 3-4) on outcomes. Univariable and multivariable logistic regression models were used to identify outcome predictors.

RESULTS

One hundred fifty-six patients were in group 1, and 72 patients were in group 2. In this cohort, HSS %Reduction was associated with decreased risk of DCI in univariate (odds ratio [OR] = 0.700 [0.527-0.923], p = 0.011) and multivariable (OR = 0.700 [0.527-0.923], p = 0.012) analyses. Higher HSS %Reduction was significantly more likely to have better outcomes at 30 days in the multivariable analysis (OR = 0.703 [0.507-0.980], p = 0.036). Initial subarachnoid blood volume was associated with outcome location at 30 days (OR = 1.331 [1.040-1.701], p = 0.023) but not DCI (OR = 0.945 [0.780-1.145], p = 0.567).

CONCLUSIONS

Early blood clearance after aSAH was associated with DCI (univariable and multivariable analyses) and outcome location at 30 days (multivariable analysis). Methods facilitating subarachnoid blood clearance warrant further investigation.

Neuromonitoring in Children with Cerebrovascular Disorders

BACKGROUND

Cerebrovascular disorders are an important cause of morbidity and mortality in children. The acute care of a child with an ischemic or hemorrhagic stroke or cerebral sinus venous thrombosis focuses on stabilizing the patient, determining the cause of the insult, and preventing secondary injury. Here, we review the use of both invasive and noninvasive neuromonitoring modalities in the care of pediatric patients with arterial ischemic stroke, nontraumatic intracranial hemorrhage, and cerebral sinus venous thrombosis.

METHODS

Narrative review of the literature on neuromonitoring in children with cerebrovascular disorders.

RESULTS

Neuroimaging, near-infrared spectroscopy, transcranial Doppler ultrasonography, continuous and quantitative electroencephalography, invasive intracranial pressure monitoring, and multimodal neuromonitoring may augment the acute care of children with cerebrovascular disorders. Neuromonitoring can play an essential role in the early identification of evolving injury in the aftermath of arterial ischemic stroke, intracranial hemorrhage, or sinus venous thrombosis, including recurrent infarction or infarct expansion, new or recurrent hemorrhage, vasospasm and delayed cerebral ischemia, status epilepticus, and intracranial hypertension, among others, and this, is turn, can facilitate real-time adjustments to treatment plans.

CONCLUSIONS

Our understanding of pediatric cerebrovascular disorders has increased dramatically over the past several years, in part due to advances in the neuromonitoring modalities that allow us to better understand these conditions. We are now poised, as a field, to take advantage of advances in neuromonitoring capabilities to determine how best to manage and treat acute cerebrovascular disorders in children.

Cerebral Digital Subtraction Angiography in Acute Intracranial Hemorrhage: Considerations in Critically Ill Children

Cerebrovascular disorders are an important cause of morbidity and mortality in children. Although minimally invasive, cerebral digital subtraction angiography (DSA) has been shown to be safe in children and is a valuable, and perhaps underutilized, technique for the diagnosis and management of pediatric cerebrovascular disorders in the critical care setting. Through a case-based approach, we explore the utility of DSA in critically ill children with acute intracranial hemorrhage (ICH). We discuss the use of DSA in the acute management of aneurysm and arteriovenous malformation rupture as well as cerebral vasospasm. Those caring for critically ill children with acute ICH should consider cerebral DSA as part of a comprehensive approach to the diagnosis and management of these conditions.

Thick and diffuse cisternal clot independently predicts vasospasm-related morbidity and poor outcome after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with significant morbidity and mortality. The presence of thick, diffuse subarachnoid blood may portend a worse clinical course and outcome, independently of other known prognostic factors such as age, aneurysm size, and initial clinical grade.

METHODS

In this post hoc analysis, patients with aSAH undergoing surgical clipping (n = 383) or endovascular coiling (n = 189) were pooled from the placebo arms of the Clazosentan to Overcome Neurological Ischemia and Infarction Occurring After Subarachnoid Hemorrhage (CONSCIOUS)-2 and CONSCIOUS-3 randomized, double-blind, placebo-controlled phase 3 studies, respectively. Patients without and with thick, diffuse SAH (≥ 4 mm thick and involving ≥ 3 basal cisterns) on admission CT scans were compared. Clot size was centrally adjudicated. All-cause mortality and vasospasm-related morbidity at 6 weeks and Glasgow Outcome Scale-Extended (GOSE) scores at 12 weeks after aSAH were assessed. The effect of the thick and diffuse cisternal aSAH on vasospasm-related morbidity and mortality, and on poor clinical outcome at 12 weeks, was evaluated using logistic regression models.

RESULTS

Overall, 294 patients (51.4%) had thick and diffuse aSAH. Compared to patients with less hemorrhage burden, these patients were older (median age 55 vs 50 years) and more often had World Federation of Neurosurgical Societies (WFNS) grade III-V SAH at admission (24.1% vs 16.5%). At 6 weeks, all-cause mortality and vasospasm-related morbidity occurred in 36.1% (95% CI 30.6%-41.8%) of patients with thick, diffuse SAH and in 14.7% (95% CI 10.8%-19.5%) of those without thick, diffuse SAH. Individual event rates were 7.5% versus 2.5% for all-cause death, 19.4% versus 6.8% for new cerebral infarct, 28.2% versus 9.4% for delayed ischemic neurological deficit, and 24.8% versus 10.8% for rescue therapy due to cerebral vasospasm, respectively. Poor clinical outcome (GOSE score ≥ 4) was observed in 32.7% (95% CI 27.3%-38.3%) and 16.2% (95% CI 12.1%-21.1%) of patients with and without thick, diffuse SAH, respectively.

CONCLUSIONS

In a large, centrally adjudicated population of patients with aSAH, WFNS grade at admission and thick, diffuse SAH independently predicted vasospasm-related morbidity and poor 12-week clinical outcome. Patients with thick, diffuse cisternal SAH may be an important cohort to target in future clinical trials of treatment for vasospasm.

Reliable Identification of Benign Clinical Course in Aneurysmal Subarachnoid Hemorrhage: A Simple and Qualitative Algorithm

BACKGROUND

A reliable method to specifically identify low vasospasm risk in aneurysmal subarachnoid hemorrhage (aSAH) patients has not been previously proposed.

OBJECTIVE

To develop a clinical algorithm using admission aSAH clinical severity and subarachnoid blood distribution to identify patients at low risk of clinical vasospasm.

METHODS

Clinical severities, admission noncontrasted head computerized tomography (CT) scan, and incidences of vasospasm among 291 aSAH patients treated at our institution were evaluated. Admission head CTs were assessed for distributions of cisternal and ventricular blood. Patients with the following 4 criteria experienced considerably lower risk of vasospasm: (1) Hunt Hess grade 1 to 2, (2) Lack of thick subarachnoid blood filling 2 adjacent cisterns, (3) Lack of thick interhemispheric blood, and (4) Lack of biventricular intraventricular hemorrhage.

RESULTS

One hundred thirty-three patients (45.7%) developed cerebral vasospasm. Hunt Hess grade greater than 2 (odds ratio [OR] 4.52, 95% confidence interval [CI] 2.74-7.46), adjacent cistern blood (OR 4.1, 95% CI 2.51-6.7), interhemispheric thick blood (OR 5.72, 95% CI 3.41-9.59), and biventricular intraventricular hemorrhage (OR 1.92, 95% CI 1.19-3.02) were significant risk factors. Application of our algorithm yielded a sensitivity of 29%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 54.5%, which was superior compared to metrics from current institutional practice criteria. Inter-rater agreement was substantial at mean kappa = 0.75.

CONCLUSION

Application of our novel clinical algorithm produced successful identification of aSAH patients who experience zero risk of clinical vasospasm. Our algorithm is simple to apply with high reliability and is superior to currently available clinical and radiographic metrics.

A Comparison of Computed Tomography-Based Scales with and without Consideration of the Presence or Absence of Intraventricular Hemorrhage in Patients with Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

There has been controversy as to whether intraventricular hemorrhage (IVH) after aneurysmal subarachnoid hemorrhage (SAH) contributes to angiographic cerebral vasospasm (aCV) and delayed cerebral ischemia (DCI). Computed tomography-based SAH scales that did and did not consider IVH were compared in terms of ability to predict aCV, DCI, and outcome.

METHODS

We reviewed 390 patients with ruptured aneurysms who had been treated surgically by day 3 by the same surgeon (T.I.). aCV was graded as 0-4. Outcome at 6 months was classified using the Glasgow Outcome Scale. Inagawa SAH grades and scores, for which only SAH was evaluated, were compared with scales that evaluated both SAH and IVH (Fisher, Claassen, and Frontera grades, and Hijdra score). The area under the receiver operating characteristic curve was calculated to compare severe aCV (grade 3-4), DCI, or poor outcome (Glasgow Outcome Scale score 1-3).

RESULTS

The Inagawa grade showed constant and significant intergrade differences in both aCV and DCI. The Inagawa grade area under the receiver operating characteristic curve values were highest among the scales examined. In the Fisher, Claassen, and Frontera grades, IVH was unlikely to be related to aCV and DCI. There was no significant difference in aCV grade or DCI occurrence between the Inagawa and Hijdra scores. In contrast, the presence of IVH was significantly associated with poor outcome.

CONCLUSIONS

In patients with aneurysmal SAH, IVH is an important factor affecting patient outcome, whereas computed tomography-based SAH scales that do not consider IVH are superior to scales that do consider it for prediction of aCV or DCI.

CT Showing Early Ventricular Dilatation after Subarachnoidal Hemorrhage

We performed a retrospective analysis of 398 patients with subarachnoidal hemorrhage (SAH) confirmed by CT. On the first CT examination the temporal horns were enlarged in 84%, the frontal horns in 32%, and the third ventricle in 21% of the patients. The amount of blood in the basal cisterns was highly correlated to dilatation of the temporal horns. The temporal horns were enlarged even when small amounts of blood were found in the cisterns. The frontal and temporal horns were dilated only when moderate or large amounts of blood were present in the cisterns. In 24 patients no blood was seen in the basal cisterns on CT performed within 5 days of the hemorrhage; none of the 3 patients with aneurysms showed normal temporal horns while 18 without demonstrable aneurysms had normal, and 3 had moderately dilated, temporal horns. Because the temporal horns cannot usually be seen at CT of healthy individuals, dilatation could be a useful sign in the diagnosis of SAH.

Spontaneous Subarachnoid Hemorrhage: Assessment of Prognosis and Initial Management in the Intensive Care Unit

Spontaneous subarachnoid hemorrhage (SAH) is asso ciated with high morbidity and mortality. Primary con servative or preoperative management in the intensive care unit aims at prevention, early detection, and treat ment of complications. In this article we review the literature on the value of initial clinical and laboratory findings in predicting complications and outcome after SAH. Current conservative management of SAH is briefly discussed.

The Hijdra scale has significant prognostic value for the functional outcome of Fisher grade 3 patients with subarachnoid hemorrhage

PURPOSE

Despite its high prevalence among patients with aneurysmal subarachnoid hemorrhage (aSAH) and high risk of delayed cerebral ischemia (DCI), the Fisher grade 3 category remains a poorly studied subgroup. The aim of this cohort study has been to investigate the prognostic value of the Hijdra sum scoring system for the functional outcome in patients with Fisher grade 3 aSAH, in order to improve the risk stratification within this Fisher category.

METHODS

Initial CT scans of 72 prospectively enrolled patients with Fisher grade 3 aSAH were analyzed, and cisternal, ventricular, and total amount of blood were graded according to the Hijdra scale. Additionally, space-occupying subarachnoid blood clots were assessed. Outcome was evaluated after 6 months.

RESULTS

Within the subgroup of Fisher grade 3, aSAH patients with an unfavorable outcome showed a significantly larger cisternal Hijdra sum score (HSS: 21.1 ± 5.2) than patients with a favorable outcome (HSS: 17.6 ± 5.9; p = 0.009). However, both the amount of ventricular blood (p = 0.165) and space-occupying blood clots (p = 0.206) appeared to have no prognostic relevance. After adjusting for the patient's age, gender, tobacco use, clinical status at admission, and presence of intracerebral hemorrhage, the cisternal and total HSS remained the only independent parameters included in multivariate logistic regression models to predict functional outcome (p < 0.01).

CONCLUSION

The cisternal Hijdra score is fairly easy to perform and the present study indicates that it has an additional predictive value for the functional outcome within the Fisher 3 category. We suggest that the Hijdra scale is a practically useful prognostic instrument for the risk evaluation after aSAH and should be applied more often in the clinical setting.

Increased risk of delayed cerebral ischemia in subarachnoid hemorrhage patients with additional intracerebral hematoma

OBJECTIVE Delayed cerebral ischemia (DCI) has a major impact on the outcome of patients suffering from aneurysmal subarachnoid hemorrhage (SAH). The aim of this study was to assess the influence of an additional intracerebral hematoma (ICH) on the occurrence of DCI. METHODS The authors conducted a single-center retrospective analysis of cases of SAH involving patients treated between 2006 and 2011. Patients who died or were transferred to another institution within 10 days after SAH without the occurrence of DCI were excluded from the analysis. RESULTS Additional ICH was present in 123 (24.4%) of 504 included patients (66.7% female). ICH was classified as frontal in 72 patients, temporal in 24, and perisylvian in 27. DCI occurred in 183 patients (36.3%). A total of 59 (32.2%) of these 183 patients presented with additional ICH, compared with 64 (19.9%) of the 321 without DCI (p = 0.002). In addition, DCI was detected significantly more frequently in patients with higher World Federation of Neurosurgical Societies (WFNS) grades. The authors compared the original and modified Fisher Scales with respect to the occurrence of DCI. The modified Fisher Scale (mFS) was superior to the original Fisher Scale (oFS) in predicting DCI. Furthermore, they suggest a new classification based on the mFS, which demonstrates the impact of additional ICH on the occurrence of DCI. After the different scales were corrected for age, sex, WFNS score, and aneurysm site, the oFS no longer was predictive for the occurrence of DCI, while the new scale demonstrated a superior capacity for prediction as compared with the mFS. CONCLUSIONS Additional ICH was associated with an increased risk of DCI in this study. Furthermore, adding the presence or absence of ICH to the mFS improved the identification of patients at the highest risk for the development of DCI. Thus, a simple adjustment of the mFS might help to identify patients at high risk for DCI.

Risk Factors for Cerebral Vasospasm Following Aneurysmal Subarachnoid Hemorrhage: A Review of the Literature

OBJECTIVE

To examine the literature on risk factors for cerebral vasospasm (CV), one of the most serious complications following aneurysmal subarachnoid hemorrhage (SAH), with special reference to the definition of CV.

METHODS

Using standard search engines, including PubMed, the medical literature on risk factors for CV after SAH was reviewed, and the best definition representative of CV was searched.

RESULTS

Severe SAH evident on computed tomography scan was the only consistent risk factor for CV after SAH. Effects of risk factors on CV, including age, clinical grade, rebleeding, intraventricular or intracerebral hemorrhage on computed tomography scan, acute hydrocephalus, aneurysm site and size, leukocytosis, interleukin-6 level, and cardiac abnormalities, appeared to be associated with the severity of SAH rather than each having a direct effect. Cigarette smoking, hypertension, and left ventricular hypertrophy on electrocardiogram were associated with CV without any relationship to SAH severity. With regard to parameters representative of CV, the grade of angiographic vasospasm (i.e., the degree of arterial narrowing evident on angiography) was the most adequate. Nevertheless, few reports on the risk factors associated with angiographic vasospasm grade have been reported to date.

CONCLUSIONS

Severe SAH evident on computed tomography scan appears to be a definite risk factor for CV after SAH, followed by cigarette smoking, hypertension, and left ventricular hypertrophy on electrocardiogram. To understand the pathogenesis of CV, further studies on the relationships between risk factors, especially factors not related to the severity of SAH, and angiographic vasospasm grade are necessary.

Retrospective analysis of predictors of cerebral vasospasm after ruptured cerebral aneurysm surgery: influence of the location of subarachnoid blood

PURPOSE

The amount of blood on computed tomography (CT) has been shown to be a predictor of cerebral vasospasm after subarachnoid hemorrhage (SAH). However, the influence of the location of the blood on the incidence of vasospasm remains unclear. We retrospectively assessed the association of the blood volumes in the individual components (cisterns and fissures) of CT scans with angiographic vasospasm after SAH.

METHODS

One hundred forty-nine SAH patients scheduled for cerebral aneurysm clipping were enrolled. The amount of subarachnoid blood was classified using the Fisher CT grade. The amounts of subarachnoid blood in 5 cisterns or 3 fissures were also evaluated using SAH scores ranging from 0 to 3 (0, no blood; 3, completely filled with blood). Cerebral vasospasm was diagnosed by the results of angiography.

RESULTS

Angiographic vasospasm developed in 51 of 149 patients (34%). Of those, 26 patients were symptomatic. The Fisher CT grade and SAH scores in the right and left sylvian fissures and suprasellar cisterns were significantly higher in patients with angiographic vasospasm than in those without it. Univariate logistic regression analysis revealed that a high Fisher CT grade and high SAH scores in the right and left sylvian fissures and suprasellar cisterns were predictors of angiographic vasospasm. Multivariate analysis indicated that the SAH score in the right sylvian fissure was an independent predictor of angiographic vasospasm (odds ratio, 3.6; 95% confidence interval (CI), 1.7-7.7; P = 0.01).

CONCLUSION

The results indicated that the amount of blood in the right sylvian fissure was significantly associated with the development of angiographic vasospasm after SAH.

Timing of computed tomography and prediction of vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND

The initial noncontrast computed tomography (CT) study of the head after an aneurysmal subarachnoid hemorrhage (SAH) is used to predict the risk of developing vasospasm. Changes in the extent of subarachnoid blood seen on CT images occur as a function of time after SAH, but there is no consensus on the time interval during which this study needs to be completed.

METHODS

Clinical and radiological information on adult SAH patients were reviewed. Patients were grouped based on the time elapsed from ictus to the initial head CT study. The amount of subarachnoid blood on CT was graded using the Hijdra sum score (HSS) and the modified Fisher scale (MFS). The relationship between the initial CT grading score and the risk of angiographic vasospasm was assessed for each group.

RESULTS

A total of 224 consecutive patients were identified (145 females, 65%). Initial CT was performed within 24 h of the event in 163 (Group 1, 73%) and after 24 h in 61 patients (Group 2, 27%). A total of 54 patients (24%) developed angiographic vasospasm. A statistically significant association between the extent of subarachnoid blood and subsequent development of vasospasm was observed only if the initial CT imaging study was performed within 24 h of aneurysmal rupture (P = 0.0001 and 0.02 for HSS and MFS, respectively).

CONCLUSIONS

We propose that only CT scans obtained within 24 h of a subarachnoid bleeding event should be used to estimate the risk of vasospasm.

Early cerebral hemodynamic alternations in patients operated on the first, second and third day after aneurysmal subarachnoid hemorrhage

Surgery timing after aneurysmal subarachnoid hemorrhage (SAH) may influence the risk of vasospasm after early surgical procedure and is correlated with SAH extensiveness. A group consisting of 127 patients with aneurysmal SAH was studied. The changes of mean flow velocity (MFV) were measured in middle cerebral artery (MCA) and in anterior cerebral artery (ACA) by transcranial Doppler sonography (TCD) in three groups of patients divided according to the surgery timing (on the first, second and third day after SAH). Changes of MFV values in MCA and in ACA were similar in all groups. MFV values in the group of patients operated on the third day were the lowest and the pathologic values lasted for the shortest time. In patients with massive SAH (Fisher IV group) and mild SAH (Fisher II group), the lowest MFV values were observed, if patients were operated within 24 hours after SAH. In patients without SAH (Fisher I group), the MFV values were the lowest, if they were operated on the third day after SAH. In patients with severe SAH (Fisher III group), the lowest risk of vasospasm was observed, if they were operated on the second day after SAH; however, the highest risk was found in patients operated on the first day after SAH. Our study suggests: (1) in patients with severe SAH operated on the second day, the lowest risk of vasospasm was observed, and the highest risk of vasospasm was observed if those were operated on the first day; (2) the highest risk of vasospasm was observed in patients operated within 24 hours with mild and massive SAH and in patients without SAH operated on the third day after SAH.

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.

Prediction of symptomatic vasospasm after subarachnoid hemorrhage: the modified fisher scale

OBJECTIVE

We developed a modification of the Fisher computed tomographic rating scale and compared it with the original Fisher scale to determine which scale best predicts symptomatic vasospasm after subarachnoid hemorrhage.

METHODS

We analyzed data from 1355 subarachnoid hemorrhage patients in the placebo arm of four randomized, double-blind, placebo-controlled studies of tirilazad. Modified Fisher computed tomographic grades were calculated on the basis of the presence of cisternal blood and intraventricular hemorrhage. Crude odds ratios (OR) reflecting the risk of developing symptomatic vasospasm were calculated for each scale level, and adjusted ORs expressing the incremental risk were calculated after controlling for known predictors of vasospasm.

RESULTS

Of 1355 patients, 451 (33%) developed symptomatic vasospasm. For the modified Fisher scale, compared with Grade 0 to 1 patients, the crude OR for vasospasm was 1.6 (95% confidence interval [CI], 1.0-2.5) for Grade 2, 1.6 (95% CI, 1.1-2.2) for Grade 3, and 2.2 (95% CI, 1.6-3.1) for Grade 4. For the original Fisher scale, referenced to Grade 1, the OR for vasospasm was 1.3 (95% CI, 0.7-2.2) for Grade 2, 2.2 (95% CI, 1.4-3.5) for Grade 3, and 1.7 (95% CI, 1.0-3.0) for Grade 4. Early angiographic vasospasm, history of hypertension, neurological grade, and elevated admission mean arterial pressure were identified as risk factors for symptomatic vasospasm. After adjusting for these variables, the modified Fisher scale remained a significant predictor of vasospasm (adjusted OR, 1.28; 95% CI, 1.06-1.54), whereas the original Fisher scale was not.

CONCLUSION

The modified Fisher scale, which accounts for thick cisternal and ventricular blood, predicts symptomatic vasospasm after subarachnoid hemorrhage more accurately than original Fisher scale.

PREDICTION OF SYMPTOMATIC VASOSPASMAFTER SUBARACHNOID HEMORRHAGE

OBJECTIVE

We developed a modification of the Fisher computed tomographic rating scale and compared it with the original Fisher scale to determine which scale best predicts symptomatic vasospasm after subarachnoid hemorrhage.

METHODS

We analyzed data from 1355 subarachnoid hemorrhage patients in the placebo arm of four randomized, double-blind, placebo-controlled studies of tirilazad. Modified Fisher computed tomographic grades were calculated on the basis of the presence of cisternal blood and intraventricular hemorrhage. Crude odds ratios (OR) reflecting the risk of developing symptomatic vasospasm were calculated for each scale level, and adjusted ORs expressing the incremental risk were calculated after controlling for known predictors of vasospasm.

RESULTS

Of 1355 patients, 451 (33%) developed symptomatic vasospasm. For the modified Fisher scale, compared with Grade 0 to 1 patients, the crude OR for vasospasm was 1.6 (95% confidence interval [CI], 1.0-2.5) for Grade 2, 1.6 (95% CI, 1.1-2.2) for Grade 3, and 2.2 (95% CI, 1.6-3.1) for Grade 4. For the original Fisher scale, referenced to Grade 1, the OR for vasospasm was 1.3 (95% CI, 0.7-2.2) for Grade 2, 2.2 (95% CI, 1.4-3.5) for Grade 3, and 1.7 (95% CI, 1.0-3.0) for Grade 4. Early angiographic vasospasm, history of hypertension, neurological grade, and elevated admission mean arterial pressure were identified as risk factors for symptomatic vasospasm. After adjusting for these variables, the modified Fisher scale remained a significant predictor of vasospasm (adjusted OR, 1.28; 95% CI, 1.06-1.54), whereas the original Fisher scale was not.

CONCLUSION

The modified Fisher scale, which accounts for thick cisternal and ventricular blood, predicts symptomatic vasospasm after subarachnoid hemorrhage more accurately than original Fisher scale.

Prediction of Cerebral Vasospasm in Patients Presenting with Aneurysmal Subarachnoid Hemorrhage: A Review

OBJECTIVE:

Cerebral vasospasm is a devastating medical complication of aneurysmal subarachnoid hemorrhage (SAH). It is associated with high morbidity and mortality rates, even after the aneurysm has been treated. A substantial amount of experimental and clinical research has been conducted in an effort to predict and prevent its occurrence. This research has contributed to significant advances in the understanding of the mechanisms leading to cerebral vasospasm. The ability to accurately and consistently predict the onset of cerebral vasospasm, however, has been challenging. This topic review describes the various methodologies and approaches that have been studied in an effort to predict the occurrence of cerebral vasospasm in patients presenting with SAH.

METHODS:

The English-language literature on the prediction of cerebral vasospasm after aneurysmal SAH was reviewed using the MEDLINE PubMed (1966–present) database.

RESULTS:

The risk factors, diagnostic imaging, bedside monitoring approaches, and pathological markers that have been evaluated to predict the occurrence of cerebral vasospasm after SAH are presented.

CONCLUSION:

To date, a large blood burden is the only consistently demonstrated risk factor for the prediction of cerebral vasospasm after SAH. Because vasospasm is such a multifactorial problem, attempts to predict its occurrence will probably require several different approaches and methodologies, as is done at present. Future improvements in the prevention of cerebral vasospasm from aneurysmal SAH will most likely require advances in our understanding of its pathophysiology and our ability to predict its onset.

Predicting the overall management outcome in patients with a subarachnoid hemorrhage accompanied by a massive intracerebral or full-packed intraventricular hemorrhage: a 15-year retrospective study

BACKGROUND

Patients with a subarachnoid hemorrhage (SAH) accompanied by a massive intracerebral hemorrhage (ICH) or a full-packed intraventricular hemorrhage (IVH) have poor outcomes. We evaluated the clinical factors to predict the overall outcome in such patients.

METHODS

Data on nontraumatic SAH patients were collected and classified into 3 groups: the pure SAH group (SAH accompanied with neither ICH nor IVH), the ICH group (SAH accompanied with a massive ICH; hematoma 30 mL), and the IVH group (SAH and all ventricles were full-packed with hematoma). One hundred seventy-nine patients were in the ICH group and 109 in the IVH group. We evaluated clinical factors, such as the Hunt & Hess (H&H) score on admission, age, sex, history, rebleeding ratio, and the computerized tomography findings (SAH score).

RESULTS

The result of multivariate logistic regression analysis of clinical variables in the ICH group, good and intermediate H&H grades, younger age (<70), no rebleeding, and lower SAH score were associated with a favorable outcome. In the result of the multivariate logistic regression analysis of clinical variables in the IVH group, only a higher SAH score was associated with an unfavorable outcome.

CONCLUSIONS

In the ICH group, factors that could be used to predict a favorable outcome included good and intermediate H&H scores (1, 2, and 3) on admission, younger age (<70), and a lower SAH score. In the IVH group, the main factor that could be used to predict a favorable outcome was a lower SAH score.

Clot volume and clearance rate as independent predictors of vasospasm after aneurysmal subarachnoid hemorrhage

OBJECT

This study was conducted for two purposes. The first was to determine whether a combination of measurements of subarachnoid clot volume, clearance rate, and density could improve prediction of which patients experience vasospasm. The second was to determine if each of these three measures could be used independently to predict vasospasm.

METHODS

Digital files of the cranial computerized tomography (CT) scans obtained in 75 consecutive patients admitted within 24 hours of subarachnoid hemorrhage (SAH) were analyzed in a blinded fashion by an observer who used quantitative imaging software to measure the volume of SAH and its density. Clot clearance rates were measured by quantifying SAH volume on subsequent CT scans. Vasospasm was defined as new onset of a focal neurological deficit or altered consciousness 5 to 12 days after SAH in the absence of other causes of deterioration, diagnosed with the aid of or exclusively by confirmatory transcranial Doppler ultrasonography and/or cerebral angiography. Univariate analysis showed that vasospasm was significantly associated with the SAH grade as classified on the Fisher scale, the initial clot volume, initial clot density, and percentage of clot cleared per day (p < 0.05). In multivariate analysis, initial clot volume and percentage of clot cleared per day were significant predictors of vasospasm (p < 0.05), whereas Fisher grade and initial clot density were not.

CONCLUSIONS

Quantitative analysis of subarachnoid clot shows that vasospasm is best predicted by initial subarachnoid clot volume and the percentage of clot cleared per day.

Volumetric quantification of Fisher Grade 3 aneurysmal subarachnoid hemorrhage: a novel method to predict symptomatic vasospasm on admission computerized tomography scans

OBJECT

Predicting which patients with aneurysmal subarachnoid hemorrhage (SAH) will develop delayed ischemic neurological deficit (DIND) due to vasospasm remains subjective and unreliable. The authors analyzed the utility of a novel software-based technique to quantify hemorrhage volume in patients with Fisher Grade 3 aneurysmal SAH.

METHODS

Patients with aneurysmal SAH in whom a computerized tomography (CT) scan was performed within 72 hours of ictus and demonstrated Fisher Grade 3 SAH were analyzed. Severe DIND was defined as new onset complete focal deficit or coma. Moderate DIND was defined as new onset partial focal deficit or impaired consciousness without coma. Fifteen consecutive patients with severe DIND, 13 consecutive patients with moderate DIND, and 12 consecutive patients without DIND were analyzed. Software-based volumetric quantification was performed on digitized admission CT scans by a single examiner blinded to clinical information. There was no significant difference in age, sex, admission Hunt and Hess grade, or time to admission CT scan among the three groups (none, moderate, or severe DIND). Patients with severe DIND had a significantly higher cisternal volume of hemorrhage (median 30.5 cm3) than patients with moderate DIND (median 12.4 cm3) and patients without DIND (median 10.3 cm3; p < 0.001). Intraparenchymal hemorrhage and intraventricular hemorrhage were not associated with DIND. All 13 patients with cisternal volumes greater than 20 cm3 developed DIND, compared with 15 of 27 patients with volumes less than 20 cm3 (p = 0.004).

CONCLUSIONS

The authors developed a simple and potentially widely applicable method to quantify SAH on CT scans. A greater volume of cisternal hemorrhage on an admission CT scan in patients with Fisher Grade 3 aneurysmal SAH is highly associated with DIND. A threshold of cisternal hemorrhage volume (> 20 cm3) may exist above which patients are very likely to develop DIND. Prospective application of software-based volumetric quantification of cisternal SAH may predict which patients will develop DIND.

Effect of cisternal and ventricular blood on risk of delayed cerebral ischemia after subarachnoid hemorrhage: the Fisher scale revisited

BACKGROUND AND PURPOSE

Thick cisternal clot on CT is a well-recognized risk factor for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Whether intraventricular hemorrhage (IVH) or intracerebral hemorrhage (ICH) predisposes to DCI is unclear. The Fisher CT grading scale identifies thick SAH but does not separately account for IVH or ICH.

METHODS

We studied 276 consecutively admitted patients with an available admission CT scan performed within 72 hours of onset. Demographic, clinical, laboratory, and neuroimaging data were recorded, and the amount and location of SAH, IVH, and ICH on admission CT scans were quantified. The relationship between these variables and DCI was analyzed separately and in combination with multiple logistic regression.

RESULTS

DCI developed in 20% of patients (54 of 276). Among SAH variables, thick clot completely filling any cistern or fissure was the best predictor of DCI (P=0.008), and among IVH variables, blood in both lateral ventricles was most predictive (P=0.001). These variables had independent predictive value for DCI in a multivariate analysis of CT findings, and both were included in a final multivariate model when evaluated in conjunction with other clinical risk factors: IVH (OR 4.1, 95% CI 1.7 to 9.8), SAH (OR 2.3, 95% CI 1.5 to 9.5), mean arterial pressure >112 mm Hg (OR 4.9, 95% CI 2.1 to 11.4), and transcranial Doppler mean velocity >140 cm/s within 5 days of hemorrhage (OR 3.8, 95% CI 1.5 to 9.5). Similar results were obtained in a repeat analysis with infarction due to vasospasm as the dependent variable.

CONCLUSIONS

SAH completely filling any cistern or fissure and IVH in the lateral ventricles are both risk factors for DCI, and their risk is additive. We propose a new SAH rating scale that accounts for the independent predictive value of subarachnoid and ventricular blood for DCI.

Health-related quality of life after aneurysmal subarachnoid hemorrhage: impacts of bleeding severity, computerized tomography findings, surgery, vasospasm, and neurological grade

OBJECT

Based on the results of earlier studies it is agreed that the significance of aneurysm location and surgery for neuropsychological impairments after subarachnoid hemorrhage (SAH) is secondary to the effects of the bleeding itself. Therefore, the present study was performed to evaluate whether bleeding, acute clinical course, and surgery have persistent effects on health-related quality of life (QOL) after SAH.

METHODS

A series of 116 patients was examined for 4 to 5 years (mean 52.2 months) after aneurysmal SAH by means of a QOL questionnaire. Eighty-six patients (74.1%) had undergone surgery early (< or = 72 hours post-SAH). There were 77 women (66.4%) and 39 men (33.6%) in the study group, and the mean age of the patients was 50.3+/-13.3 years (range 30-69 years). Patients who had undergone surgery for a left-sided middle cerebral artery (MCA) aneurysm complained of significantly more impairments in social contact, communication, and cognition than those treated for a right-sided MCA aneurysm. No other effects of aneurysm location (including the anterior communicating artery) emerged. Multiple aneurysms, intraoperative aneurysm rupture, and partial resection of the gyrus rectus had no adverse effects on later daily life. Only temporary clipping was associated with increased complaints in some QOL areas. Disturbances of the circulation of cerebrospinal fluid and the presence of intraventricular hemorrhage led to more impairments in daily life. Specific effects of the anatomical pattern of the bleeding could be identified, but no adverse effects of vasospasm were found. Multivariate analyses revealed, in particular, that patient age and admission neurological status (Hunt and Hess grade) are substantial predictors of the psychosocial sequelae of SAH.

CONCLUSIONS

In contrast to the mild effects of aneurysm surgery, patient's age, initial neurological state on admission, and the bleeding pattern substantially influence late QOL after SAH.

Functional outcome after aneurysmal subarachnoid hemorrhage

The introduction of the operating microscope, the principle of early surgery, specialized intensive care units, the calcium antagonist nimodipine, the sophisticated pre- and postoperative management and an aggressive antiischemic pharmacological management have substantially reduced morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH). In spite of this progress, many patients after rupture and surgical repair of an intracranial aneurysm exhibit substantial cognitive deficits and emotional problems although their neurological outcome was rated as good according to the Glasgow Outcome Scale (GOS = I). Therefore, a comprehensive neuropsychological examination is called for in order to evaluate the factual functional outcome after SAH. Neither focal brain damage associated with aneurysm location nor surgery but the hemorrhage itself and related events can be regarded as the most important causal factors for the late result after SAH. In contrast to the mild permanent effects of aneurysm surgery, the initial bleeding itself seems to have substantial lasting adverse neurobehavioral effects after. In concordance with other authors our own data stress the strong predictive power of the bleeding pattern such as the presence of intraventricular and/or intracerebral blood on the functional outcome after aneurysmal SAH.

Cognitive deficits in the acute stage after subarachnoid hemorrhage

OBJECTIVE

In spite of fundamentally improved medical management of subarachnoid hemorrhage (SAH), many patients remain mentally impaired. However, the causes of these disturbances are unclear. The present study was performed to elucidate the significance of the hemorrhage itself and related events in the neuropsychological performance of patients in the acute stage after SAH.

METHODS

A series of 51 patients were examined, by means of a battery of cognitive tests, 1 to 13 days (mean, 5.9 d) after SAH. Thirty-three patients had experienced ruptured aneurysms, and 18 had sustained SAH of unknown origin. Furthermore, 25 patients who had undergone surgical treatment (a mean of 5.0 d earlier) of prolapsed lumbar discs served as a control group.

RESULTS

The cognitive deficits of the patients after aneurysmal SAH proved to be comparable to those after spontaneous SAH of unknown origin, with the single exception of a significantly worse (P = 0.003) concentration capacity in the surgically treated group. The severity of SAH in computed tomographic scans correlated (up to r = 0.57, P < 0.001) with poor performance on tests of memory, concentration, divided attention, and perseveration. Frontal intracerebral hemorrhage led to significantly more errors in an aphasia screening test (P < 0.001) and a test of perseveration (P < 0.001). If acute hydrocephalus was present, the patients exhibited worse long-term memory (P < 0.001), showed slower reaction times (P = 0.01), and made more errors in the perseveration test (P = 0.004). Patients with intraventricular blood performed at significantly lower levels in the concentration (P = 0.001), divided attention (P = 0.01), long-term memory (P < 0.001), and perseveration (P = 0.003) tests.

CONCLUSION

The results emphasize that the severity of SAH (Fisher score) is the most important factor related to cognitive dysfunction, but frontal hematoma, intraventricular hemorrhage, and acute hydrocephalus were also associated with cognitive deficits, compared with patients with SAH without these findings.

Is transcranial Doppler sonography useful in detecting late cerebral ischaemia after aneurysmal subarachnoid haemorrhage?

Transcranial Doppler (TCD) examination was performed in 109 patients with aneurysmal subarachnoid haemorrhage. Fifty-seven demonstrated flow velocities exceeding 120 cm/s in the middle cerebral artery. Of these, 23 developed delayed ischaemic deficit (DID). Mean flow velocity in this group was 170, SD 12.8 cm/s, in comparison with 155, SD 11.2 cm/s in the 34 patients without late signs of cerebral ischaemia. This difference is significant (p = 0.0269). In the 34 patients without DID, but TCD > 120 cm/s, 17 received anti-ischaemic therapy based on TCD values only, while 17 were given no additional treatment. The mean TCD values and the neurological outcome in the two groups were similar. A rapid increase in flow velocities of 50 cm/s or more during a 24-h period seemed to be a strong predictor of symptomatic vasospasm as seven out of 12 patients developed DID, five with permanent neurological sequelae. The study confirms results from other centres, that a strict correlation between high TCD flow velocities and occurrence of DID does not exist.

The use of computed tomography in the prediction of delayed cerebral infarction following acute aneurysm surgery for subarachnoid haemorrhage

In order to predict the occurrence of cerebral infarction after aneurysmal surgery in patients with subarachnoid haemorrhage, we measured the amount of subarachnoid blood on initial and on postoperative computed tomograms. We used a reliable grading method to estimate the amount of blood on computed tomograms in 24 patients with infarction due to vasospasm and 45 patients without cerebral infarction, all of whom underwent aneurysmal surgery within 48 hours after the ictus. The total amount of subarachnoid blood on admission and on the day after operation was more in the cerebral infarction group than in the non-infarction group. The clearance rate of subarachnoid blood by surgery was lower in patients with cerebral infarction than in patients without infarction and the predominant site of subarachnoid blood corresponded with the site of the infarct. Of 24 patients with cerebral infarction, 22 (92%) belonged to the group whose initial total blood score was more than 10 on admission and whose clearance rate by surgery was less than 50%. Therefore, we propose this range to be an indication for the occurrence of cerebral infarction in postoperative patients due to cerebral vasospasm. The presence of intracerebral haematoma and the amount of ventricular blood and their clearance by surgery were also estimated for the prediction of delayed cerebral infarction after aneurysmal surgery. However, they had no relation to the occurrence of cerebral infarction due to vasospasm.

Subarachnoid blood on CT and memory dysfunctions in aneurysmal subarachnoid hemorrhage

Ninety patients with a previous subarachnoid haemorrhage (SAH) were given a set of memory tests comprising immediate free recall of words (indexing long-term memory, LTM, and short-term memory, STM), final free recall of words (indexing LTM), final cued recall of words (indexing LTM), and a digit span test (indexing working memory, WM). Patients with a large amount of blood on CT, carried out within 72 h of the bleed, showed LTM as well as STM dysfunction, whereas patients with a small amount of subarachnoid blood evidenced only STM dysfunction. Patients with the ruptured aneurysm located on the anterior cerebral artery, however, constituted an exception with dysfunction of both LTM and STM together with intact WM, independent of the amount of subarachnoid blood. Also, patients with internal carotid artery or middle cerebral artery aneurysms and large volume SAH displayed LTM dysfunction, but differed concerning STM, the former showing intact STM and the latter showing STM dysfunction. Thus, it appears, that the combined information from factors such as the amount of subarachnoid blood and the location of the ruptured aneurysm is of vital importance for explaining the different patterns of memory dysfunctions after SAH.

Transcranial Doppler detection of vertebrobasilar vasospasm following subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Transcranial Doppler sonography is of established value in the detection and monitoring of middle cerebral artery vasospasm. Little information exists on the utility of transcranial Doppler for detection of posterior circulation vasospasm.

METHODS

Cerebral angiography and conventional hand-held transcranial Doppler sonography were compared to determine sensitivity and specificity of transcranial Doppler for detection of vertebral and basilar artery vasospasm.

RESULTS

Of 59 consecutive subarachnoid hemorrhage patients with transcranial Doppler angiogram correlations, 42 underwent posterior circulation angiography to evaluate 64 vertebral arteries and 42 basilar arteries during the period of risk for vasospasm and had technically adequate transcranial Doppler examinations within 24 hours of the angiogram. A mean flow velocity of 60 cm/s and above was indicative of both vertebral and basilar artery vasospasm. For the vertebral artery, there were 7 true-positive test results, 42 true-negatives, 6 false-positives (unknown cause in 3, increased collateral flow in 1, adjacent vessel vasospasm in 1, hyperperfusion in 1), and 9 false-negatives (anatomic in 7, operator error in 2). Sensitivity was 44% and specificity was 87.5%. For the basilar artery, there were 10 true-positives, 23 true-negatives, 6 false-positives (unknown cause in 4, hyperemia/hyperperfusion in 1, increased collateral flow in 1), and 3 false-negatives (operator error in 2, tortuous vessel course in 1). Sensitivity was 76.9% and specificity was 79.3%. When the diagnostic criterion was changed to > or = 80 cm/s (vertebral artery) and > or = 95 cm/s (basilar artery), all false-positive results were eliminated (specificity and positive predictive value, 100%).

CONCLUSIONS

Our data suggest that transcranial Doppler has good specificity for the detection of vertebral artery vasospasm and good sensitivity and specificity for the detection of basilar artery vasospasm. Transcranial Doppler is highly specific (100%) for vertebral and basilar artery vasospasm when flow velocities are > or = 80 and > or = 95 cm/s, respectively.

Prediction of delayed neurological deficit after subarachnoid haemorrhage: a CT blood load and Doppler velocity approach

The predictive value of cranial computed tomography (CT) blood load and serial transcranial Doppler sonography for the development of delayed ischaemic neurological deficit was assessed in 121 patients following subarachnoid haemorrhage. Of the 121 patients, 81 (67%) had thick layers of blood or haematoma, including intraventricular bleeding. The proportion of patients who developed delayed deficit was higher with increasing amounts of subarachnoid blood on the admission CT (51% of 53 cases in Fisher grade 3; 35% of 33 cases in grade 2; 28% of 7 cases in grade 1, P < 0.01). Doppler velocities obtained from readings at least every 2 days following admission were higher in patients with delayed neurological deficit (peak velocity for grade 3 patients 176 +/- 6 cm/s (mean +/- SE), versus grade 2: 164 +/- 7 cm/s; grade 4 149 +/- 9, both P = 0.04, Mann-Whitney). Peak velocity and maximal 24-h rise tended to be higher within different CT grades in patients with a deficit than in those without; this difference was significant for grade 3 patients (P < 0.01). We conclude that a combined approach with CT and Doppler sonography provides greater predictive value for the development of delayed ischaemic neurological deficit than either test considered independently. The value of Doppler sonography may be greatest for patients with Fisher grade 3 blood, in whom the risk of delayed ischaemia is greatest.

Cerebral vasospasm following post-traumatic subarachnoid hemorrhage evaluated by transcranial Doppler ultrasonography

We studied the incidence and time course of flow velocity changes suggesting a vasospasm following post-traumatic subarachnoid hemorrhage (SAH) considering the intracranial pressure (ICP) in 38 SAH patients as compared to 30 patients with spontaneous SAH. The first investigation was done within 24 h after onset of hemorrhage and regularly followed up during the clinical course. Additionally, the index of cerebral circulatory resistance was calculated and the ICP was measured using an epidural transducer. A significant correlation between middle cerebral artery maximum mean flow velocity and the quantity of blood seen on a computed tomographic scan in patients with post-traumatic SAH indicates a similar pathogenetic mechanism of the development of vasospasm to that after spontaneous SAH. In contrast, there was a significantly earlier occurrence of mean flow velocities over 120 cm/s following post-traumatic SAH irrespective of the ICP. Therefore, additional factors must be considered in the evaluation of these pathologically raised flow velocities after posttraumatic SAH. In both SAH groups there was a highly significant correlation between clinical outcome and clinical grade on admission, ICP and resistance index. The weak correlation between maximum mean flow velocity and clinical outcome following post-traumatic SAH supports the notion that final clinical outcome of these patients is of multifactorial origin.

Amount of blood on computed tomography as an independent predictor after aneurysm rupture

BACKGROUND AND PURPOSE

After admission to the hospital of patients with aneurysmal subarachnoid hemorrhage, we assessed the predictive value of the extent of the hemorrhage on computed tomography in addition to that of clinical grading scales for poor outcome, infarction, and rebleeding.

METHODS

We studied 471 consecutive patients with aneurysmal subarachnoid hemorrhage and used logistic regression with step-wise forward selection of variables.

RESULTS

On admission, poor outcome was predicted by a low Glasgow Coma Scale score (odds ratio, 0.8; 95% confidence interval, 0.7-0.9); treatment with fluid restriction (2.5; 1.6-4.0); age over 52 (2.6; 1.7-3.9); loss of consciousness at ictus (1.7; 1.1-2.6); or a large amount of subarachnoid blood (2.0; 1.3-3.1). Delayed infarction was predicted by a large amount of subarachnoid blood (1.8; 1.2-2.6) or treatment with tranexamic acid (1.6; 1.1-2.4). Rebleeding was predicted by treatment with tranexamic acid (0.4; 0.3-0.7; protective effect); age over 52 (1.9; 1.2-3.0); loss of consciousness at ictus (1.7; 1.1-2.7); or admission to a neurosurgery service (0.6; 0.3-0.9; protective effect). Comparison of the observed and predicted outcome events showed that inclusion of the amount of subarachnoid blood into a predictive model added little to the prediction of poor outcome in general, but much to the prediction of delayed cerebral ischemia.

CONCLUSIONS

The total amount of subarachnoid blood on the initial computed tomogram has independent predictive power for the occurrence of delayed cerebral ischemia.

A simple scoring system for accurate prediction of outcome within four days of a subarachnoid haemorrhage

This study was designed to examine the consistency of a number of easily identifiable predictive factors in assessing outcome within four days of a subarachnoid haemorrhage. Patients with a proven subarachnoid haemorrhage, aged between 15-65, of any neurological grade who had bled within 72 hours of admission, and who had undergone a CT scan within 96 hours of the ictus, were included. Three groups of patients were studied prospectively. The studies were separated in time and place. The series were similar overall but there were some variations between the three groups of patients because of alterations in referral patterns and management strategies between the series. There were significant differences in the patients' ages, grades on admission, timing of angiography, negative angiography rate and timing of operation. This did not affect overall outcome; 57%, 61% and 59% of the patients in series 1, 2 and 3 respectively making a good recovery. The proportion of patients with a poor outcome was also similar. To identify the level of risk of an individual patient within the first few days of haemorrhage, we considered a number of early predictive factors. Two emerged as strong predictors of outcome; the early neurological grade and the distribution of blood on the CT scan. We developed a simple scoring system from the first series, based on these findings, designed to predict outcome at three months. The scoring system was calculated on the basis of the distribution of blood seen on the CT scan and the patients' neurological grade on admission. Two points each were scored for interhemispheric, intraventricular, basal or intracerebral blood (excluding blood in the sylvian fissures). Patients in grade 1-3 scored -1, grade 4 scored 0, grades 5 & 6 scored +5. The scan score and grade score were summated to give the overall score. Patients were placed in risk groups (low, score -1; medium, score 0-2; high, score 3+). The scoring system was then applied prospectively to the two subsequent groups of patients. In each of the three series there was a clear correlation between the patients' scores and their outcomes but more importantly the probability of each outcome for each risk group was considered. In both the second and third series the probability of a full recovery in the low risk group was very likely--P = 0.000.(ABSTRACT TRUNCATED AT 400 WORDS)

Outcome of patients with aneurysmal and presumed aneurysmal bleeding. A hospital study based on 100 consecutive cases in a neurological clinic

One hundred patients with spontaneous subarachnoid hemorrhage due to aneurysm or presumed aneurysm consecutively admitted to a neurological clinic and subjected to CCT during the first 72 hours were examined retrospectively. The outcome after two months as defined by the Glasgow Outcome Scale (GOS) was relatively good: 23% of the patients suffered management mortality (GOS I) (postoperative lethality 8%), 3% showed GOS-Grade II, 14% grade III, 17% grade IV, and 43% grade V. The extent of intracranial hemorrhage correlated well with the initial Hunt-Hess Grade which, in turn, had a strong influence on case fatality and the degree of disability. Lethal factors were: 1. massive subarachnoid hemorrhage together with a massive ventricular hemorrhage (p < 0.001), 2. massive subarachnoid hemorrhage together with an intracerebral hematoma > 20 ml (p < 0.05). Case fatality was lower when angiography was negative. In our study rebleeding (12%) and delayed cerebral ischemia (DCI) (18%) were less frequent and the lethality due to acute hydrocephalus (5%) and delayed cerebral ischemia (5%) was less pronounced than in comparable studies. The degree of disability (GOS) was directly related to the amount of intracranial blood, to the development of acute or chronic hydrocephalus, delayed cerebral ischemia and rebleeding. DCI occurred in 60% of patients with marked hydrocephalus. Rebleeding was more frequent in patients with acute hydrocephalus. Hydrocephalus, DCI, and rebleeding were associated with a poorer initial grade on the Hunt and Hess Scale.

Infarction after aneurysm rupture does not depend on distribution or clearance rate of blood

BACKGROUND AND PURPOSE

We sought to determine the contribution of the amount, distribution, and clearance rate of extravasated blood in relation to occurrence of infarction and outcome in patients with aneurysmal subarachnoid hemorrhage.

METHODS

We prospectively studied 59 consecutive patients with aneurysmal subarachnoid hemorrhage admitted within 72 hours by means of serial computed tomographic scanning, close clinical observation, and assessment of outcome after 3 months.

RESULTS

Infarction occurred in 17 of the 59 patients. The arterial territories involved hardly reflected the distribution of subarachnoid blood in the basal cisterns on computed tomography, and even the side of the infarcts corresponded only weakly with the side on which most extravasated blood was seen. Infarction occurred twice as often in patients with large amounts of subarachnoid blood; this difference was not significant on its own but is in agreement with previous studies. A low clearance rate of cisternal blood was not related to the occurrence of infarction; a relation between clearance rate and poor outcome was largely explained by the amount of subarachnoid blood on the initial computed tomogram and by a low Glasgow Coma Scale score on admission.

CONCLUSIONS

The fact that infarction is related to the total amount but not to the distribution or clearance rate of extravasated blood argues against a direct role of extravasated blood and in favor of systemic factors, dependent on the severity of the initial hemorrhage.

Cognitive deficits after rupture and early repair of anterior communicating artery aneurysms

In a retrospective follow-up study covering a time period of four years 18 patients operated upon early for an aneurysm of the anterior communicating artery (ACoA) and a control group of 21 patients with aneurysmal subarachnoid haemorrhage (SAH) from other sources than ACoA aneurysm and 9 patients with SAH of nonaneurysmal origin were subjected to neuropsychological examination. Both groups were comparable in their neurological condition on admission and in the severity of bleeding seen on CT-scan. Testing included memory functions, concentration, logical and spatial thinking, a Stroop-test, an aphasia screening test and a complex choice reaction task. Patients with SAH of a ruptured ACoA aneurysm did not differ significantly from the control group in any of the tests used. But there was a trend for the ACoA patients to have more memory problems than the patients with SAH of other origins. On the other hand the patients in the control group with aneurysmal SAH of other locations and with non-aneurysmal SAH had not significantly more problems with concentration and aphasia than the patients with ruptured ACoA aneurysm. These results, which differ from the common opinion of frequent occurrence of memory deficits in ACoA aneurysms are interpreted as a consequence of the changes in improved pre-, intra- and postoperative management in modern neurosurgery.

Deriving clinical prediction rules from stroke outcome research

BACKGROUND AND PURPOSE

Our purpose was to determine whether clinical prediction rules could be derived from current stroke outcome research.

SUMMARY OF REPORT

We reviewed 92 articles on stroke outcome research to determine their suitability for implementation as a clinical prediction rule. Methodological problems in many of these studies made implementation of their results as a clinical prediction rule difficult.

CONCLUSIONS

Implementation of stroke outcome research as clinical prediction rules would be facilitated by description of patient population demographics; precise definitions of predictor and outcome measures; stratification of patients by stroke mechanism; use of adequate patient sample sizes; and description of the mathematical methods used, including coding schemes, cutpoints, beta coefficients, constant terms, and a priori probabilities.

Cerebral vasospasm evaluated by transcranial Doppler ultrasonography at different intracranial pressures

The present study evaluates the interdependence of clinical stage, cerebral vasospasm, intracranial pressure (ICP), and transcranial Doppler ultrasonographic parameters. The mean flow velocity of blood in the middle cerebral artery and the index of cerebral circulatory resistance as a measure of the peripheral vascular flow resistance were determined in 76 patients with spontaneous subarachnoid hemorrhage. The ICP was measured using an epidural transducer in 41 patients. There was no case in which both high ICP and a high mean flow velocity were observed simultaneously. The investigations led to the following conclusions. 1) In patients with a resistance index of less than 0.5, changes in the mean flow velocity seem to reflect sufficiently the actual severity and time course of vasospasm. 2) During the time course of vasospasm, an increase in the resistance index above values of 0.6 with a simultaneously decreased mean flow velocity indicates a rise in ICP rather than a reduction in vasospasm. 3) With a pronounced increase in ICP, evaluation of the severity and time course of vasospasm by transcranial Doppler ultrasonography based solely upon the mean flow velocity can lead to false-negative results.

Cerebral blood flow and metabolism following subarachnoid haemorrhage: effect of subarachnoid blood

The amount of effused blood following a subarachnoid haemorrhage (SAH) was estimated in 48 patients by cerebral computerized tomographic scanning. The cerebral oxygen consumption (CMRO2) was calculated as arteriovenous difference for oxygen multiplied by mean cerebral blood flow measured by the 133-Xe inhalation technique. A significant negative correlation was observed between CMRO2 and amount of subarachnoid blood, with additional reduction in CMRO2 in case of ventricular bleeding. Cerebral blood flow on admission, opposed to CMRO2, showed no correlation to amount of blood on CT scan. A correlation was observed for blood flow measured at day 5 and further on, indicating a restored coupling between flow and metabolism. The clinical (Hunt) grade on admission and the outcome correlated to the amount of blood. These observations suggest that the acute reduction in CMRO2 following a SAH is mainly determined by the amount of blood escaping during the aneurysm rupture, and that the cerebral blood flow level a few days after SAH mainly is determined by the initial reduction in oxygen uptake.

Platelet thromboxane release and delayed cerebral ischemia in patients with subarachnoid hemorrhage

Adenosine diphosphate-induced platelet aggregation and associated thromboxane B2 release were studied in 52 patients with subarachnoid hemorrhage (SAH) in order to detect a possible association between altered platelet function and development of cerebral ischemic complications after SAH. Compared to the values on admission, the patients showed significantly increased platelet aggregability (p less than 0.05) and thromboxane release (p less than 0.001) 1 to 2 weeks after SAH. The highest values of thromboxane release were seen in patients who deteriorated due to delayed cerebral ischemia with a permanent neurological deficit. Thromboxane release was significantly higher (p less than 0.05) before the onset of severe delayed ischemia in six patients with preoperative ischemia compared to the patients without delayed ischemia. In five others, both ischemic deterioration and elevated thromboxane release occurred after operation. These patients had preoperative values similar to the values in those without ischemic symptoms. The observations suggest that increased platelet aggregability and thromboxane release are associated with delayed cerebral ischemia both before and after surgery.

Grading the amount of blood on computed tomograms after subarachnoid hemorrhage

According to several studies, the amount of subarachnoid blood on the initial computed tomogram of patients with aneurysmal subarachnoid hemorrhage has predictive value with respect to infarction and outcome. Of several methods for assessing the amount of subarachnoid blood, none has been subjected to a study of interobserver agreement. We describe our own method, applied in previous studies, in which the amounts of blood in 10 basal cisterns and fissures and in four ventricles are graded separately. In grading single computed tomograms of 182 consecutive patients with subarachnoid hemorrhage, the agreement between pairs of three observers, studied with kappa statistics, was relatively good for individual cisterns or fissures (kappa between 0.35 and 0.65) and ventricles (kappa between 0.47 and 0.74). The Spearman rank correlation coefficients for the sum of the scores for subarachnoid and intraventricular blood were very high. Summed scores for extravasated blood are suitable as a baseline variable in follow-up studies of patients with subarachnoid hemorrhage.

Acute surgery in intracranial aneurysms. Experience with 100 cases

In the last 3.5 years (up to August 1988) out of 450 patients with surgically treated intracranial aneurysms in 100 cases (22%) acute surgery was performed (up to 72 h after SAH). Patients in grade I-III (WFNS scale) were operated upon. In all the cases there were supratentorial aneurysms. CSF drainage during the operation was used routinely and nimodipine topically, in intravenous infusion and orally was applied. In all the cases, but one, the aneurysms was clipped. Follow-up--1 year. Assessment of the results was done using the Glasgow Outcome Scale (GOS). Full recovery was obtained in 78 patients and further 5 patients are independent. There were 14 deaths, in 7 patients due to postoperative vasospasm. Symptomatic ischaemia developed in 25 patients, however, in 15 of them it was fully reversible, due to the possibility of aggressive antivasospastic treatment (hypervolaemia, induced arterial hypertension). The relatively worse results were obtained in patients with chronic arterial hypertension.