Late Recurrence of Subarachnoid Hemorrhage after Treatment for Ruptured Aneurysms: Patient Characteristics and Outcomes

Risk of intracranial aneurysm recurrence after microsurgical clipping based on 3D digital subtraction angiography

OBJECTIVE

Current knowledge of recurrence rates after intracranial aneurysm (IA) surgery relies on 2D digital subtraction angiography (DSA), which fails to detect more than 75% of small aneurysm remnants. Accordingly, the discrimination between recurrence and growth of a remnant remains challenging, and actual assessment of recurrence risk of clipped IAs could be inaccurate. The authors report, for the first time, 3D-DSA-based long-term durability and risk factor data of IA recurrence and remnant growth after microsurgical clipping.

METHODS

Prospectively collected data for 305 patients, with a total of 329 clipped IAs that underwent baseline 3D-DSA, were evaluated. The incidence of recurrent IA was described by Kaplan-Meier curves. Risk factors for IA recurrence were analyzed by multivariable Cox proportional hazards and logistic regression models.

RESULTS

The overall observed proportion of IA recurrence after clipping was 2.7% (9 of 329 IAs) at a mean follow-up of 46 months (0.7% per year). While completely obliterated IAs did not recur during follow-up, incompletely clipped aneurysms (76 of 329) demonstrated remnant growth in 11.8% (3.4% per year). Young age and large initial IA size significantly increased the risk of IA recurrence.

CONCLUSIONS

The findings support those in previous studies that hypothesized that completely clipped IAs have an extremely low risk of recurrence. Conversely, the results highlight the significant risk posed by incompletely clipped IAs. Young patients with initial large IAs and incomplete obliteration have an especially high risk for IA recurrence and therefore should be monitored more closely.

Incidence rate and predictors of recurrent aneurysms after clipping: long-term follow-up study of survivors of subarachnoid hemorrhage

Recurrent aneurysms are a major cause of re-aneurysmal subarachnoid hemorrhage (aSAH), but information on long-term clip durability and predictors is insufficient. This study aimed to present the incidence rate of > 10 years and investigate predictors of a recurrent aneurysm in aSAH survivors. We included 1601 patients admitted with aSAH and treated by microsurgical clipping between January 1993 and May 2010. Of these patients, 435 aSAH survivors were included in this study (27.2%). The total follow-up time was 5680.9 patient-years, and the overall incidence rate was 0.77% per patient-year. The cumulative probability of recurrence without residua and regrowth of the neck remnant was 0.7% and 13.9% at 10 years, respectively. Neck remnant (hazard ratio [HR], 10.311; 95% confidence interval [CI], 5.233-20.313) and alcohol consumption over the moderate amount (HR, 3.166; 95% CI, 1.313-7.637) were independent risk factors of recurrent aneurysm. Current smoking and multiplicity at initial aSAH presentation were significant factors in a univariate analysis. Furthermore, de novo intracranial aneurysms (DNIAs) were more common in the recurrent group than in the non-recurrent group (40.9% vs. 11.5%, P < 0.001). In the present study, we noted the long-term clip durability and predictor of recurrence after microsurgical clipping. These findings can assist clinicians in identifying patients at a high risk of recurrent aneurysm and recommending selective long-term surveillance after microsurgical clipping.

Pathogenic Factors and Prognosis of De Novo Aneurysms vAfter Aneurysm Clipping

OBJECTIVE

To confirm this hypothesis, this study aimed to explore the pathogenic factors, prognosis, and their relationship in de novo aneurysms and to reach a consensus on their management.

METHODS

First, the clinical data of 5 patients with de novo aneurysms from April 1998 to October 2021 were analyzed retrospectively. Then, the English literature on de novo aneurysms reported in Pubmed from 1985 to 2021 was systematically reviewed, and 18 case reports from 17 articles and 16 case series were identified. Univariate and multivariate analyses and modified Fisher test were used to analyze the relationship between pathogenic factors and prognosis.

RESULTS

Hypertension was noted in 60% of our clinical cases, 50% of the case series identified in the literature review, and 66.7% of the case reports in the literature review. In the case reports identified from our literature review, the proportion of original aneurysms in the anterior circulation was 96.3%. Moreover, in our 5 cases, all original aneurysms occurred in the anterior circulation. The rupture rate of original aneurysms in our 5 cases was 100%, and that of the cases reported in the literature review was 88.9%. Univariate logistic analysis showed that the time interval was related to the prognosis of de novo aneurysms with a P value of 0.048 and an odds ratio of 0.968 (95% confidence interval 0.938-1.000). Modified Fisher exact tests showed that patient age at the occurrence of de novo aneurysm P = 0.029) was related to the prognosis of de novo aneurysms.

CONCLUSIONS

Hypertension, an original aneurysms located in the anterior circulation and rupture represent the pathogenic factors associated with de novo aneurysms. The time interval to de novo aneurysm and patient age at the occurrence of de novo aneurysm are predictive of prognosis. Based on the above information, we can prevent and improve the prognosis of de novo aneurysms.

Value of 3-Dimensional Digital Subtraction Angiography for Detection and Classification of Intracranial Aneurysm Remnants After Clipping

BACKGROUND

The current gold standard for evaluation of the surgical result after intracranial aneurysm (IA) clipping is two-dimensional (2D) digital subtraction angiography (DSA). While there is growing evidence that postoperative 3D-DSA is superior to 2D-DSA, there is a lack of data on intraoperative comparison.

OBJECTIVE

To compare the diagnostic yield of detection of IA remnants in intra- and postoperative 3D-DSA, categorize the remnants based on 3D-DSA findings, and examine associations between missed 2D-DSA remnants and IA characteristics.

METHODS

We evaluated 232 clipped IAs that were examined with intraoperative or postoperative 3D-DSA. Variables analyzed included patient demographics, IA and remnant distinguishing characteristics, and 2D- and 3D-DSA findings. Maximal IA remnant size detected by 3D-DSA was measured using a 3-point scale of 2-mm increments.

RESULTS

Although 3D-DSA detected all clipped IA remnants, 2D-DSA missed 30.4% (7 of 23) and 38.9% (14 of 36) clipped IA remnants in intraoperative and postoperative imaging, respectively (95% CI: 30 [ 12, 49] %; P-value .023 and 39 [23, 55] %; P-value = <.001), and more often missed grade 1 (< 2 mm) clipped remnants (odds ratio [95% CI]: 4.3 [1.6, 12.7], P-value .005).

CONCLUSION

Compared with 2D-DSA, 3D-DSA achieves a better diagnostic yield in the evaluation of clipped IA. Our proposed method to grade 3D-DSA remnants proved to be simple and practical. Especially small IA remnants have a high risk to be missed in 2D-DSA. We advocate routine use of either intraoperative or postoperative 3D-DSA as a baseline for lifelong follow-up of clipped IA.

Intracranial post-clipping residual or recurrent aneurysms: Current status and treatment options (Review)

Following the clipping of intracranial aneurysms, post-clipping residual or recurrent aneurysms (PCRRAs) can occur. In recent years, the incidence of PCRRAs has increased due to a prolonged follow-up period and advanced imaging techniques. However, several aspects of intracranial PCRRAs remain unclear. Therefore, the present study performed an in-depth review of the literature on PCRRAs. Herein, a summary of PCRRAs that can be divided into the following two categories is presented: i) Those occurring after the incomplete clipping of an aneurysm, where the residual aneurysm regrows into a PCRRA; and ii) those occurring after the complete clipping of an aneurysm, in which a de novo aneurysm occurs at the original aneurysm site. Currently, digital subtracted angiography remains the gold standard for the imaging diagnosis of PCRRAs as it can eliminate metallic clip artifacts. Intracranial symptomatic PCRRAs should be actively treated, particularly those that have ruptured. A number of methods are currently available for the treatment of intracranial PCRRAs; these mainly include re-clipping, endovascular treatment (EVT) and bypass surgery. Currently, re-clipping remains the most effective method used to treat PCRRAs; however, it is a very difficult procedure to perform. EVT can also be used to treat intracranial PCRRAs. EVT methods include coiling (stent- or balloon-assisted) and flow-diverting stents (or coiling-assisted). Bypass surgery can be selected for difficult-to-treat, complex PCRRAs. On the whole, following appropriate treatment, the majority of intracranial PCRRAs achieve a high occlusion rate and a good prognosis.

Rupture of De Novo Middle Cerebral Artery Aneurysm 8 Years After the Clipping of Ruptured M1 Middle Cerebral Artery Aneurysm

BACKGROUND Development and rupture of a de novo intracranial aneurysm is rare. Little is known regarding its etiology and the appropriate timing of follow-up angiograms after surgical clipping or coiling. CASE REPORT We present a case report of a 39-year-old male smoker with history of hypertension who developed a de novo aneurysm 8 years after surgical clipping of an aneurysm in the middle cerebral artery in the same segment. He presented with neck rigidity and drowsiness. Laboratory analysis did not show blood dyscrasia. Brain computerized tomography showed right temporal lobe hematoma and 4-vessel angiogram demonstrated de novo aneurysm in the same segment of the M1 middle cerebral artery, which was confirmed by intraoperative microsurgical findings. We review the literature on such cases and discuss the pathophysiology, diagnosis, and treatment of this condition. De novo aneurysm, although rare, can develop within days to as long as 10 years after surgical clipping or coiling. CONCLUSIONS This rare case of de novo aneurysm supports follow-up imaging of patients after initial surgical clipping for up to 10 years.

LATE ANEURYSM RELAPSE AFTER MICROSURGICAL TREATMENT OF MIDDLE CEREBRAL ARTERY ANEURYSM: A CASE REPORT AND LITERATURE REVIEW OF TREATMENT OPTIONS

Recurrence of intracranial aneurysm after initial microsurgical or endovascular treatment is uncommon. Although the exact etiology remains unknown, recurrent aneurysms may be observed in surgical patients with big and multiple aneurysms, arterial hypertension, non-atherosclerotic cerebrovascular arteriopathies, as well as in those with a familial history of the disease. Such recurrence can occur over a wide period ranging from several months to years after the initial aneurysm treatment. Still, the occurrence delayed by more than 20 years is rather unusual. Herein, we present a case of a 70-year-old female patient who developed late intracranial aneurysm relapse 30 years after successful microsurgical clipping of the middle cerebral artery aneurysm. We also provide a brief review of relevant literature, discussing the etiology and pathophysiology of aneurysm reappearance, as well as different treatment options available. In conclusion, one should always consider the possibility of intracranial aneurysm recurrence regardless of the mode and time of primary surgery. In such a case, a multidisciplinary management approach using flow diverting endovascular techniques is advised in selected patients.

Formation of intracranial de novo aneurysms and recurrence after neck clipping: a systematic review and meta-analysis

OBJECTIVE

Incidence rates of de novo aneurysm formation and recurrence after clip ligation remain controversial. In this meta-analysis, the authors provide data on pooled annual incidence rates and the association of patient characteristics with time to formation of de novo aneurysms and time to recurrence after clipping.

METHODS

A search of the literature up to June 15, 2016, on PubMed and a systematic review were performed. The association of age, aneurysm rupture status, aneurysm multiplicity, and anatomical location with time to recurrence or formation of de novo aneurysm was estimated using multivariable Cox proportional-hazards models. Kaplan-Meier estimates (event-free survival curves) are shown. Pooled annualized incidence rates of recurrent and de novo aneurysms were estimated using Poisson regression. Proportions of aneurysms and average follow-up times are displayed as bubble plots with LOESS smoothers weighted for study size.

RESULTS

Of the 7606 articles screened, 92 were included in the study. Case reports on 101 patients with recurrent aneurysms and 132 patients with de novo aneurysms were analyzed. Long-term follow-up studies on de novo aneurysm formation included 13,723 patients with 101,378 patient-years of follow-up; studies on aneurysm recurrence included 5922 patients with 31,055 patient-years of follow-up. Mean time to recurrence was 12.9 ± 6.6 years (mean ± standard deviation), and mean time to de novo formation was 9.3 ± 6.1 years. No association with sex, aneurysm location, and initial rupture could be shown. De novo aneurysms occurred later in patients with multiplicity of aneurysms at diagnosis (HR 0.63, p = 0.03) and in patients with increasing age (HR per 10 yrs 0.88, p = 0.06). Pooled annualized incidence rates were 0.35% for de novo aneurysms and 0.13% for recurrent aneurysms.

CONCLUSIONS

Despite low reported annual incidence rates, the cumulative risk of 9.6%-22% for aneurysm recurrence or de novo formation 20 years after clip ligation warrants lifelong follow-up. Screening at 5, 10, and 20 years would detect 30.8% (95% CI 23.3%-37.6%), 64.2% (95% CI 55.9%-70.9%), and 95.9% (95% CI 90.9%-97.9%) of de novo aneurysms. Screening for recurrent aneurysms at 10, 15, and 20 years would detect 36.6% (95% CI 26.5%-45.4%), 65.3% (95% CI 54.7%-73.5%), and 95.1% (95% CI 85.8%-96.6%) of lesions.

Sex differences in stroke

Sex disparities within the field of stroke, including subarachnoid hemorrhages (SAHs), have been in focus during the last 2 decades. It is clear that stroke incidence is higher in men, and also that men have their first stroke earlier than women. On the other hand, women have more severe strokes, mainly because cardioembolic strokes are more common in women. This leads to higher case fatality and worse functional outcome in women. It has often been pointed out that women more often have nontraditional stroke symptoms, and therefore may seek medical help later. After discharge from the hospital, female stroke survivors live alone in many cases and are dependent on external care. Therefore, these women frequently rate their quality of life (QoL) lower than men do. Female spouses more often provide help to their male stroke survivors than the reverse, and they accept a heavier burden. These caregivers are at high risk for depression, low QoL, and low psychologic wellbeing. SAH is a special form of stroke, often caused by a ruptured aneurysm. It is about 20% more common in women. The case fatality is high, but does not differ between the sexes.

Endovascular coiling versus neurosurgical clipping for people with aneurysmal subarachnoid haemorrhage

BACKGROUND

Around 30% of people who are admitted to hospital with aneurysmal subarachnoid haemorrhage (SAH) will rebleed in the initial month after the haemorrhage if the aneurysm is not treated. The two most commonly used methods to occlude the aneurysm for prevention of rebleeding are microsurgical clipping of the neck of the aneurysm and occlusion of the lumen of the aneurysm by means of endovascular coiling. This is an update of a systematic review that was previously published in 2005.

OBJECTIVES

To compare the effects of endovascular coiling versus neurosurgical clipping in people with aneurysmal SAH on poor outcome, rebleeding, neurological deficit, and treatment complications.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (March 2018). In addition, we searched CENTRAL (2018, Issue 2), MEDLINE (1966 to March 2018), Embase (1980 to March 2018), US National Institutes of Health Ongoing Trials Register (March 2018), and World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (last searched March 2018). We also contacted trialists.

SELECTION CRITERIA

We included randomised trials comparing endovascular coiling with neurosurgical clipping in people with SAH from a ruptured aneurysm.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data, and assessed trial quality and risk of bias using the GRADE approach. We contacted trialists to obtain missing information. We defined poor outcome as death or dependence in daily activities (modified Rankin scale 3 to 6 or Glasgow Outcome Scale (GOS) 1 to 3). In the special worst-case scenario analysis, we assumed all participants in the group with better outcome with missing follow-up information had a poor outcome and those in the other group with missing data a good outcome.

MAIN RESULTS

We included four randomised trials involving 2458 participants (range per trial: 20 to 2143 participants). Evidence is mostly based on the largest trial. Most participants were in good clinical condition and had an aneurysm on the anterior circulation. None of the included trials was at low risk of bias in all domains. One trial was at unclear risk in one domain, two trials at unclear risk in three domains, and one trial at high risk in one domain.After one year of follow-up, 24% of participants randomised to endovascular treatment and 32% of participants randomised to the surgical treatment group had poor functional outcome. The risk ratio (RR) of poor outcome (death or dependency) for endovascular coiling versus neurosurgical clipping was 0.77 (95% confidence interval (CI) 0.67 to 0.87; 4 trials, 2429 participants, moderate-quality evidence), and the absolute risk reduction was 7% (95% CI 4% to 11%). In the worst-case scenario analysis for poor outcome, the RR for endovascular coiling versus neurosurgical clipping was 0.80 (95% CI 0.71 to 0.91), and the absolute risk reduction was 6% (95% CI 2% to 10%). The RR of death at 12 months was 0.80 (95% CI 0.63 to 1.02; 4 trials, 2429 participants, moderate-quality evidence). In a subgroup analysis of participants with an anterior circulation aneurysm, the RR of poor outcome was 0.78 (95% CI 0.68 to 0.90; 2 trials, 2157 participants, moderate-quality evidence), and the absolute risk decrease was 7% (95% CI 3% to 10%). In subgroup analysis of those with a posterior circulation aneurysm, the RR was 0.41 (95% CI 0.19 to 0.92; 2 trials, 69 participants, low-quality evidence), and the absolute decrease in risk was 27% (95% CI 6% to 48%). At five years, 28% of participants randomised to endovascular treatment and 32% of participants randomised to surgical treatment had poor functional outcome. The RR of poor outcome for endovascular coiling versus neurosurgical clipping was 0.87 (95% CI 0.75 to 1.01, 1 trial, 1724 participants, low-quality evidence). At 10 years, 35% participants allocated to endovascular and 43% participants allocated to surgical treatment had poor functional outcome. At 10 years RR of poor outcome for endovascular coiling versus neurosurgical clipping was 0.81 (95% CI 0.70 to 0.92; 1 trial, 1316 participants, low-quality evidence). The RR of delayed cerebral ischaemia at two to three months for endovascular coiling versus neurosurgical clipping was 0.84 (95% CI 0.74 to 0.96; 4 trials, 2450 participants, moderate-quality evidence). The RR of rebleeding for endovascular coiling versus neurosurgical clipping was 1.83 (95% CI 1.04 to 3.23; 4 trials, 2458 participants, high-quality evidence) at one year, and 2.69 (95% CI 1.50 to 4.81; 1 trial, 1323 participants, low-quality evidence) at 10 years. The RR of complications from intervention for endovascular coiling versus neurosurgical clipping was 1.05 (95% CI 0.44 to 2.53; 2 trials, 129 participants, low-quality evidence).

AUTHORS' CONCLUSIONS

The evidence in this systematic review comes mainly from one large trial, and long-term follow-up is available only for a subgroup of participants within that trial. For people in good clinical condition with ruptured aneurysms of either the anterior or posterior circulation the data from randomised trials show that, if the aneurysm is considered suitable for both neurosurgical clipping and endovascular coiling, coiling is associated with a better outcome. There is no reliable trial evidence that can be used directly to guide treatment in people with a poor clinical condition.

Treatment of Recurrent Intracranial Aneurysms After Clipping: A Report of 23 Cases and a Review of the Literature

OBJECTIVE

There are no established treatment strategies for aneurysms that recur after clipping. In this study, we present cases of patients who experienced recurrent aneurysms after clipping and subsequently underwent surgical intervention.

METHODS

Between 2004 and 2015, we surgically treated 23 aneurysms that recurred at a previously clipped site. Patient characteristics and clinical history were retrospectively reviewed.

RESULTS

Patients included 19 women and 4 men 45-81 years old. Aneurysms recurred 3-31 years (mean, 15.4 years) after the initial operation. For 18 cases, the first clinical presentation was a subarachnoid hemorrhage; aneurysms were incidentally diagnosed in 5 patients. Aneurysm locations were as follows: 9 on the internal carotid artery; 4 on the middle cerebral artery; 7 on the anterior communicating artery; 2 on the distal anterior cerebral artery; and 1 on the basilar artery. The reasons for retreatment included subarachnoid hemorrhage (n = 9) and aneurysm regrowth detected on follow-up examinations (n = 14). Endovascular treatment was performed in 10 cases, and direct surgery was performed in 13 cases (clipping in 8, clipping or trapping with bypass in 5). Various complex vascular reconstructions, including high-flow bypass and intracranial-intracranial in situ bypass, were performed for recurrent aneurysms.

CONCLUSIONS

In our experience, coil embolization is a safe and effective procedure for treating recurrent aneurysms. When cases are unsuitable for coil embolization, surgical treatment often requires neurosurgeons not only to overcome the general technical difficulty of reoperative clipping but also to perform challenging vascular reconstruction.

Timing of retreatment for patients with previously coiled or clipped intracranial aneurysms: Analysis of 156 patients with multiple treatments

Background:

Some patients require a second surgical intervention for recurrence of treated aneurysms, untreated aneurysms in patients with multiple lesions, or de novo aneurysm. This retrospective review of the data was undertaken to evaluate when retreatment is necessary after initial aneurysm treatment.

Methods:

Cerebral aneurysms in 1755 patients were treated via clipping or coiling between January 1995 and September 2012. Postoperative follow-up was performed at 6 months after treatment and was repeated every 12 months (or longer) after treatment using three-dimensional computed tomography angiography or magnetic resonance angiography.

Results:

A cumulative total of 156 patients (8.9%) (117 women, 39 men; mean age: 55.0 years; range: 25–79 years) needed retreatment for rupture or regrowth of aneurysm (n = 31; ruptured (R)/remaining unruptured (U), 26/5), formation of de novo aneurysm (n = 45; R/U, 23/22), known untreated aneurysm in patients with multiple lesions (n = 78; R/U, 5/73), and hemorrhage from undetected aneurysm (n = 2). The regrowth risk is higher after endovascular treatment than after craniotomy and clipping. Median time to retreatment was 187 months (range: 11–280 months) for regrowth, 165 months (range: 22–330 months) for de novo, and 24 months (range: 2.8–417 months) for known untreated aneurysm. Regrowth or known with subarachnoid hemorrhage were frequently treated within 2 years from initial treatment.

Conclusions:

Aneurysms with residua or untreated aneurysms in patients with multiple lesions carry a risk of bleeding during a relatively short period, whereas there is a small but significant risk of de novo formation and subsequent hemorrhage at over 10 years after previous treatment.

Long-term subarachnoid haemorrhage survivors still die due to cerebrovascular causes

OBJECTIVE

Subarachnoid haemorrhage (SAH) is associated with sympathetic nervous activation and inflammation. SAH could therefore theoretically be a risk factor for development of cardiovascular disease. The aim of this study was to investigate whether long-term (≥1 year) SAH survivors had an increased risk of death due to cardiovascular causes.

MATERIAL & METHODS

SAH patients ≥18 years treated at Umeå University Hospital between 1986 and 2006 were eligible for inclusion. Deceased patients were identified in the Swedish population register. Death certificates from long-term SAH survivors and causes of death in the general population were obtained from the National Board of Health and Welfare, Sweden. The prevalence of comorbidities at the time of SAH was compared with the distribution of cardiovascular risk factors in the northern Sweden MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Disease) health survey. Analyses were stratified for age and sex.

RESULTS

In the SAH patients, the median year of SAH was 1992 and the median year of death was 2001. The MONICA survey in 1994 and the distribution of deaths in the general population in 2001 were used for comparison. Long-term SAH survivors had, compared to the general population, a significantly increased risk for death due to cerebrovascular disease (P < 0.0001), but not for death due to cardiovascular disease. Hypertension was more common in SAH patients compared to survey participants (P < 0.01).

CONCLUSION

Cerebrovascular causes of death were significantly more common in long-term survivors after SAH compared to the general population.

Computerized Angiographic Occlusion Rating for Ruptured Clipped Aneurysms is Superior to Subjective Occlusion Rating

BACKGROUND AND PURPOSE

The computerized occlusion rating to estimate angiographic occlusion of embolized aneurysms is superior to the subjective occlusion rating. In this study, we compared the 2 methods in the analysis of aneurysms clipped after subarachnoid hemorrhage.

MATERIALS AND METHODS

The pre- and postoperative angiographic images (DSA) of 95 selected patients were analyzed and stratified in 4 grades (grade 0 for 100%, grade I for <99%-90%, grade II for <89%-70%, grade III for <70% occlusion) by using the subjective (angiographic) occlusion rating and the computerized (angiographic) occlusion rating. For the subjective occlusion rating, the occlusion rate was estimated; for the computerized occlusion rating, the "occluded" and "nonoccluded" aneurysm areas were automatically calculated in square millimeters after outlining the ideal occlusion line.

RESULTS

With the subjective occlusion rating, 75 (78.9%), 12 (12.6%), 7 (7.4%), and 1 (1.1%) and with the computerized occlusion rating 45 (47.4%), 24 (25.3%), 20 (21.0%), and 6 (6.3%) patients had aneurysms stratified to grades 0, I, II and III, respectively. The interobserver variation was significant with the subjective occlusion rating but not with the computerized occlusion rating. The subjective occlusion rating overestimated aneurysm occlusion in 30 (31.6%) patients. Mean values were the following: subjective occlusion rating of 97.5 ± 6.3% and computerized occlusion rating of 93.5 ± 9.7%; P = < .001. No patient rebled, and 4 patients underwent retreatment during 36 ± 38.9 months; the predictive value (log-rank, Kaplan-Meier) of the subjective and computerized occlusion ratings with respect to retreatment was highly significant for both methods (subjective occlusion rating: χ(2), 29.65; P < .001; computerized occlusion rating: χ(2), 35.57, P < .001).

CONCLUSIONS

The 2 methods showed remarkable differences in the estimation of the angiographic occlusion rates of clipped aneurysms. The clearly lower interobserver variation of the computerized versus subjective occlusion rating may indicate a superiority of the computerized occlusion rating.

[De novo cerebral aneurysms]

OBJECTIVE

To substantiate the reasonability and duration of angiographic follow-up of patients operated on for cerebral aneurysms to rule out de novo aneurysm formation.

MATERIAL AND METHODS

The results of angiographic examination (cerebral angiography and SCT angiography) of 43 patients with cerebral aneurysms operated on at the Burdenko Neurosurgical Institute in 1995-2012 are analyzed. The follow-up duration varied from 1 to 14 years after surgery (mean duration, 5 years). Patients' age ranged from 14 to 56 years.

RESULTS

Control angiographic examination showed that de novo aneurysms were formed in 7 (16.2%) patients. A total of 8 de novo aneurysms were detected (in one case there were two aneurysms formed). All aneurysms, both the previously operated and the de novo ones, were located in the anterior part of the circle of Willis. De novo aneurysms were clipped in 5 cases; the cavity of the de novo aneurysm was occluded with spirals in one case. One patient with a small aneurysm of the middle cerebral artery refused surgery. Neither lethal nor unfavorable outcomes were recorded.

CONCLUSIONS

The patient groups with the high risk of de novo aneurysm formation are as follows: 1) young smokers with hypertension; 2) patients who developed clinical signs of the disease when being young; 3) patients subjected to proximal exclusion of the main artery; and 4) patients with multiple and familial forms of the pathology. Dynamic angiographic follow-up (SCT angiography or magnetic resonance angiography) for 1-3 years is recommended for these patients.

Subarachnoid hemorrhage and the female sex: analysis of risk factors, aneurysm characteristics, and outcomes

OBJECT

The pathophysiology of aneurysmal subarachnoid hemorrhage (aSAH) is unclear. Sex may play a role in the outcome of patients with aSAH.

METHODS

The authors retrospectively identified 617 patients with aSAH (April 2005 to February 2010) and analyzed sex differences in risk factors (age, hypertension, smoking, alcohol consumption, and family history), admission-related factors (World Federation of Neurosurgical Societies grade and admission delay), aneurysm characteristics (site, side, location, and multiplicity), and outcomes (treatment modalities [coiling/clipping/both/conservative], complications [vasospasm and hydrocephalus], length of stay, and modified Rankin Scale score at 3 months).

RESULTS

The female patients with aSAH were older than the male patients (mean age 56.6 vs 51.9 years, respectively, p < 0.001), and more women than men were ≥ 55 years old (56.2% vs 40.4%, respectively, p < 0.001). Women exhibited higher rates of bilateral (6.8% vs 2.6%, respectively, p < 0.05), multiple (11.5% vs 5.2%, respectively, p < 0.05), and internal carotid artery (ICA) (36.9% vs 17.5%, respectively, p < 0.001) aneurysms and a lower rate of anterior cerebral artery aneurysms (26.3% vs 44.8%, respectively, p < 0.001) than the men, but no side differences were noted. There were no sex differences in risk factors, admission-related factors, or outcome measures. For both sexes, outcomes varied according to aneurysm location, with odds ratios for a poor outcome of 1.62 (95% CI 0.91-2.86, p = 0.1) for middle cerebral artery, 2.41 (95% CI 1.29-4.51, p = 0.01) for ICA, and 2.41 (95% CI 1.29-4.51, p = 0.006) for posterior circulation aneurysms compared with those for anterior cerebral artery aneurysms. The odds ratio for poor outcome (modified Rankin Scale score of 4-6) in women compared with men after adjusting for significant prognostic factors was 0.71 (95% CI 0.45-1.11, p > 0.05).

CONCLUSIONS

The overall outcomes after aSAH between women and men are similar.

What is the role of clipping surgery for ruptured cerebral aneurysms in the endovascular era? A review of recent technical advances and problems to be solved

Craniotomy and clipping have been robust treatments for ruptured cerebral aneurysm for more than 50 years, with satisfactory overall outcomes. Technical advances, such as developments in microsurgical tools and equipment, adjunctive therapy, and novel monitoring methods enable safer and more efficient treatment. However, overall surgical results have not shown any major improvements, as outcomes are mainly determined by the damage from initial bleeding, and new treatment strategies are not always free from associated complications and problems. Recent advances in endovascular treatment are shifting the treatment for ruptured cerebral aneurysm from craniotomy and clipping to intravascular coil embolization. However, craniotomy and clipping are very important for the treatment of ruptured cerebral aneurysm. This paper discusses recent advances and future perspectives in the field of clipping surgery for ruptured aneurysms.

Coiling as Retreatment in Intracranial Aneurysm of de novo Formation or Regrowth: Case Report

Development of de novo aneurysm or aneurysm regrowth after complete clipping of an intracranial aneurysm is rare. We report coiled cases of de novo aneurysm and aneurysm regrowth. We retrospectively reviewed 107 cases of intracranial aneurysm coiling performed in our hospital, identifying five cases of coiled aneurysm that were de novo aneurysm or aneurysm regrowth. In all the cases, total or near total occlusion was seen. There were no complications related to the procedure. In two of the three patients with ruptured aneurysms, consciousness level on admission was stupor. When the patient was discharged after the treatment, one of them had 4 of the modified Rankin Scale. The other one had 5 on discharge. The rest three patients had 0. As for a de novo aneurysm or a regrowth of aneurysm, coiling may be considered when clipping is difficult.

Influence of hemodynamics on recanalization of totally occluded intracranial aneurysms: a patient-specific computational fluid dynamic simulation study

Object

Some totally occluded intracranial aneurysms may recur. The role of hemodynamic mechanisms in this process remains to be elucidated. The authors used computational fluid dynamic analysis and investigated the local hemodynamic characteristics at the aneurysm neck before and after total embolization, attempting to identify hemodynamic risk factors leading to recurrence of totally embolized aneurysms.

Methods

Between May 2008 and June 2010, the authors recruited 17 consecutive patients with totally occluded intracranial aneurysms (7 recanalized and 10 stable lesions). Using patient-specific 3D digital subtraction angiography data, the hemodynamic features before and after embolization were retrospectively characterized.

Results

The overall preembolization blood flow patterns were nearly the same in the recanalized and stable groups, with no significant difference in either the maximum wall shear stress (WSS) (p = 0.914) or the spatially averaged WSS (p = 0.322) at peak systole at the aneurysm neck. After occlusion, the overall flow pattern changed, and the WSS distribution at the treated aneurysm neck differed in the 2 groups. In all of the 7 recanalized cases, both the maximum WSS and spatially averaged WSS at peak systole at the treated aneurysm neck were higher than those at the aneurysm neck before embolization. In contrast, both parameters were decreased in 70%–80% of the stable cases. After embolization, both the maximum WSS (p = 0.021) and spatially averaged WSS (p = 0.041) at peak systole at the treated aneurysm neck were higher in the recanalized group than in the stable group.

Conclusions

Higher WSS at the treated aneurysm neck after total embolization can be an important hemodynamic factor that contributes to aneurysm recurrence after endovascular treatment.

Sixty-four-row multislice computed tomographic angiography in the diagnosis and characterization of intracranial aneurysms: comparison with 3D rotational angiography

BACKGROUND

Sixty-four-row multislice computed tomographic angiography (CTA) has great potential for use in vascular studies. The aim of our study was to compare 64-slice CTA with three-dimensional rotational angiography (3DRA) in the detection and characterization of intracranial aneurysms with special attention to smaller (<3-mm) aneurysms.

METHODS

In a prospective study, a total of 133 patients were included who successively underwent 64-slice CTA and digital subtraction angiography (DSA) examinations for suspected intracranial aneurysms. The 64-slice CTA, conventional DSA, and 3DRA images were independently reviewed by five readers who performed the presence, shape, dimension, and location of aneurysms. The 3DRA results were considered as the ultimate reference standard.

RESULTS

The reference standard revealed 111 aneurysms in 93 patients: 27 aneurysms were read as <3 mm, 66 were read as being between 3 and 8 mm, and 18 were read as >8 mm. The sensitivities of 64-slice CTA for aneurysms<3 mm, between 3 and 8 mm, and >8 mm were 96.3%, 98.5%, and 100%, respectively, on a per-aneurysm basis. The sensitivities of conventional DSA for aneurysms<3 mm, between 3 and 8 mm, and >8 mm were 85.2%, 100%, and 100%, respectively, on a per-aneurysm basis. The 64-slice CT angiographic images could clearly show the aneurysmal characteristics and the relationship between aneurysms and adjacent branch vessels.

CONCLUSION

Sixty-four-slice CTA is a highly accurate imaging examination of the first-line imaging technique for detecting and characterizing intracranial aneurysms including <3-mm aneurysms.

Postoperative Assessment of Clipped Aneurysms With 64-Slice Computerized Tomography Angiography

BACKGROUND

Multidetector computerized tomography angiography (MDCTA) is now a widely accepted technique for the management of intracranial aneurysms.

OBJECTIVE

To evaluate its accuracy for the postoperative assessment of clipped intracranial aneurysms.

METHODS

We analyzed a consecutive series of 31 patients that underwent direct surgical clipping procedures of 38 aneurysms. A 64 slice MDCT scanner (Aquilion 64, Toshiba) was used and results were compared with digital subtraction angiographies (DSA). Two independent neuroradiologists analyzed the following data: examination quality, artifacts, aneurysm remnant, and patency of collateral branches. Interobserver agreement, sensitivity, and specificity were calculated.

RESULTS

Seventy-nine percent of the aneurysms were located in the anterior circulation. Significant artifacts were found with multiple and cobalt-alloy clips. According to DSA, remnants &gt;2 mm were found in 21% of the cases, and 2 patients had one collateral branch occluded. Sensitivity and specificity of 64-MDCTA for the detection of aneurysm remnants were 50% and 100%, respectively. Sensitivity and specificity of 64-MDCTA for the detection of a significant remnant (&gt;2 mm) and the detection of the occlusion of a collateral branch were, respectively, 67% and 100% and 50% and 100%. No relationship was found with the location, type, shape, size, or number of clips, but missed remnants tended to be larger with cobalt-alloy clips.

CONCLUSIONS

64-MDCTA is a valuable technique to assess the presence of a significant postoperative remnant in single titanium clip application cases and might be useful for long-term follow-up. DSA remains the most accurate postoperative radiological examination.

Unruptured intracranial aneurysms: initial and follow-up screening

Subarachnoid hemorrhage (SAH) from a ruptured intracranial aneurysm is a devastating disease that causes death or severe disability in half of patients. Intracranial aneurysms are not present at birth but develop during life. Actively searching and treating intracranial aneurysms before rupture may prevent SAH as a result of these aneurysms. The prevalence of intracranial aneurysms is approximately 2% in the general population, but higher in subgroups such as patients who have survived an episode of SAH, persons with a family history of SAH and patients with polycystic kidney disease. Screening for intracranial aneurysms should be considered in these high-risk groups. Some of the intracranial aneurysms detected with screening will be too small to be treated, and may therefore be followed over time, which can cause anxiety in the patient. In this article, we discuss current knowledge, remaining questions and future perspectives in screening and follow-up imaging for unruptured intracranial aneurysms.

Three-dimensional digital subtraction angiographic evaluation of aneurysm remnants after clip placement

OBJECTIVE

The aneurysm remnants rate was evaluated via three-dimensional digital subtraction angiography (3D-DSA) in the postoperative evaluation of clipped aneurysms.

METHODS

Data on surgically clipped aneurysms of anterior circulation obtained via postoperative 3D-DSA from February 2007 to March 2009 were gathered. The results of the postoperative 3D-DSA and of two-dimensional digital subtraction angiography (2D-DSA) for the detection of aneurysm remnants were compared, and an investigation was performed as to why 2D-DSA had missed some aneurysm remnants that were detected in the 3D-DSA. Various surgical factors that revealed aneurysm remnants in the 3D-DSA were also evaluated.

RESULTS

A total of 39 neck remnants of 202 clipped aneurysms (19.3%) were confirmed in 3D-DSA, and these were classified according to Sindou's classification of aneurysm remnants. Patients with only a neck remnant found in the 3D-DSA represented 17.3% (35/202 aneurysms) of the whole series, and those with a residuum of neck plus sac found in the 3D-DSA represented 1.9% (4/202 aneurysms). The causes of aneurysm remnants were no full visualization (14/39, 35.9%), parent and perforator artery protection (10/39, 25.6%), clip design problems (8/39, 20.5%), and broad-necked aneurysm (7/39, 17.9%).

CONCLUSION

Patients with </= 2 mm aneurysm remnants showed an increased risk of undetectable aneurysm remnants in the 2D-DSA. The most frequent location of the missed aneurysm in 2D-DSA was the anterior communicating artery. 3D-DSA showed more aneurysm remnants than what is indicated in the existing literature, the 2D-DSA.

Recurrent subarachnoid hemorrhage after complete obliteration of intracranial aneurysm

The authors report a case of recurrent subarachnoid hemorrhage (SAH) after complete occlusion of an intracranial aneurysm. It is known that regrowth of an aneurysm after the complete clipping is a rare event. For detection of recurrence, however, it may be necessary to follow up with the patient regularly after the initial operation for intracranial aneurysms, because re-rupture of an aneurysm can cause a fatal result, and the cumulative risk of a recurrent SAH is thought to be not low over time.

Concept of ideal closure line for clipping of middle cerebral artery aneurysms--technical note

The concept of optimum closure line was applied to a series of 51 consecutive middle cerebral artery aneurysms (14 ruptured, 37 unruptured) in 41 patients, 16 men and 25 women aged 29-79 years (mean 59.1 years). Visual inspection through the operating microscope revealed 3 types of aneurysm based on the origin of the aneurysm: bifurcation type (n = 39), trunk type (n = 9), and combined type (n = 3). Clipping along the optimum closure line should restore the vascular structure to the original configuration. Combination clip techniques were useful to form a curved closure line. This technique requires adequate operative fields with dissection of the aneurysm and related arteries from the neighboring structures as far as possible. The closure line concept is helpful to decide how to apply clips for particular aneurysms to avoid risks of ischemic complication and future recurrence. Combination clip techniques are often necessary to match a curved closure line.

Post-treatment hemodynamics of a basilar aneurysm and bifurcation

To investigate whether or not a successful aneurysm treatment procedure can subject a parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. Prior to treatment, the aneurysm at systole is filled with a periodic train of vortex tubes, which form at the aneurysm neck and advect upwards into the dome. Following the treatment procedure however, the motion of the vortex train is inhibited by the aneurysm filling material, which confines the vortex tubes to the region beneath the aneurysm neck. Analysis of the post-treatment flow field indicates that the impingement of the basilar artery flow upon the treated aneurysm neck and the close proximity of a vortex tube to the parent artery wall increase the maximum wall shear stresses to values approximately equal to 50 Pa at systole. Calculation of the time-averaged wall shear stresses indicates that there is a 1.4 x 10(-7) m(2) area on the parent artery exposed to wall shear stresses greater than 37.9 Pa, a value shown by Fry [Circ. Res. 22(2):165-197, 1968] to cause severe damage to the endothelial cells that line the artery wall. The results of this study demonstrate that it is possible for a treatment procedure, which successfully isolates the aneurysm from the circulation and leaves no aneurysm neck remnant, to elevate the hemodynamic stresses to levels that are injurious to the artery wall.

Effectiveness and costs of screening for aneurysms every 5 years after subarachnoid hemorrhage

BACKGROUND

Patients who survive after subarachnoid hemorrhage (SAH) are at risk for a recurrence despite successful treatment of the ruptured aneurysm and may therefore benefit from screening for new aneurysms.

METHODS

We screened 610 patients with SAH with CT angiography 2-18 years after clipping of the aneurysms. Results of screening were used as input for a Markov decision model. We compared the expected number of recurrent hemorrhages, life expectancy, quality-adjusted life-years (QALYs), and costs associated with the strategies "screening every 5 years" and "no screening."

RESULTS

Screening individuals with previous SAH prevented almost half of the recurrences, slightly increased life expectancy (from 21.06 to 21.08 years), but reduced QALYs (from 12.18 to 12.04) and increased costs (from $2,750 to $4,165 per patient). Screening was cost-saving without increasing QALYs in patients with a more than twofold risk above baseline of both aneurysm formation and rupture and it was cost-saving while increasing QALYs if both risks were at least 4.5 times higher. In patients with reduced quality of life because of fear for a recurrence, screening increased QALYs at a maximum cost of $17,422 per QALY.

CONCLUSIONS

In general, screening patients with previous subarachnoid hemorrhage (SAH) cannot be recommended. Screening can save costs and increase quality-adjusted life-years (QALYs) in patients with a relatively high risk of both aneurysm formation and rupture, and increases QALYs at acceptable costs in patients with fear for a recurrence. More data are needed on risk factors for aneurysm formation and rupture in patients with previous SAH and on management of fear for a recurrence to identify patients who can benefit from screening.

Could late rebleeding overturn the superiority of cranial aneurysm coil embolization over clip ligation seen in the International Subarachnoid Aneurysm Trial?

OBJECT

The present purpose is to define the sensitivity of the superiority of coil embolization observed in the International Subarachnoid Aneurysm Trial (ISAT) according to the rate of late rebleeding over a reasonable range, and to find the range of rebleeding rates for which it may be overturned. In the ISAT, coil embolization appears to be safer than clip ligation at 1 year, and clip occlusion has better long-term efficacy at preventing rebleeding. This leaves open the question of which is better in the longer term.

METHODS

The authors calculate the life expectancy of patients following a subarachnoid hemorrhage (SAH) and compare the life expectancy of those who underwent coil embolization with those who underwent clip ligation in the ISAT cohort.

RESULTS

The 1-year poor outcome rate following treatment climbs rapidly with advancing age. A consequence is that the absolute difference between the poor outcome rates after coil embolization and clip occlusion is lower in those < 50 years of age (3.3%) than it is for those > 50 years of age (10.1%). This difference may be enough to give clip application the advantage in the < 40-year-old group despite the small size of the difference in 1-year rebleeding rates thus far observed (0.152%).

CONCLUSIONS

When treating ruptured cerebral aneurysms, the advantage of coil embolization over clip ligation cannot be assumed for patients < 40 years old. In this age range the difference in the safety of the 2 procedures is small, and the better long-term protection from SAH afforded by clip placement may give this treatment an advantage in life expectancy for patients < 40 years of age.

Rebleeding after endovascular embolization of ruptured cerebral aneurysms

This study retrospectively reviewed 227 patients with ruptured solitary cerebral aneurysm who underwent endovascular embolization with detachable coils between March 1997 and March 2006 to establish the incidence of rebleeding after endovascular treatment for ruptured cerebral aneurysm and identify the risk factors. The site and size of the aneurysm, the interval between treatment and rebleeding, and the outcome were investigated in six of the 227 patients (2.6%) who rebled after treatment. Four patients had large or giant aneurysms located on the internal carotid artery at the origin of the posterior communicating artery. The interval between treatment and rebleeding was less than 1 year in four patients (mean 394.2 days). Two patients died, and the survivors had modified Rankin Scale scores of 0, 2, 3, and 4. Re-embolization was performed in four patients and no further bleeding occurred during the mean follow-up period of 1.9 years after re-treatment. Patients with giant aneurysms of the internal carotid artery are at increased risk for rebleeding. Re-treatment should be considered if there is conventional and/or magnetic resonance angiographic evidence of dome filling. Patients with ruptured cerebral aneurysms must be followed up with diagnostic imaging closely during the first 12 months post-embolization because rebleeding frequently occurs within 1 year after initial treatment. Re-embolization is safe and effective in patients with recurrent hemorrhage from aneurysms previously embolized with detachable coils.

Life Expectancy After Perimesencephalic Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Patients with a perimesencephalic nonaneurysmal subarachnoid hemorrhage are not at risk for rebleeding in the initial years after the hemorrhage. Nevertheless, uncertainty remains on the long-term prognosis after perimesencephalic hemorrhage, and former patients are often considered high-risk cases for health insurance or are denied life insurance. We performed a very long-term follow-up study of a large consecutive series of such patients and compared mortality in this cohort with that in the general population.

METHODS

All patients with a perimesencephalic hemorrhage (defined by pattern of hemorrhage on computed tomography within 72 hours after onset and absence of aneurysm) admitted between 1983 and 2005 to our service were followed-up by telephone. For patients who had died, we retrieved age and cause of death. We compared the age- and sex-specific mortality of this cohort with that of the general population by means of standardized mortality ratios with corresponding 95% confidence intervals.

RESULTS

The cohort consisted of 160 patients, with a total number of patient-years of 1213. No new episodes of subarachnoid hemorrhage had occurred. During follow-up 11 patients had died; the expected number of deaths based on mortality rates in the general population (adjusted for age and gender) was 18.1. The standardized mortality ratio was 0.61 (95% confidence interval, 0.34 to 1.1).

CONCLUSIONS

Patients with perimesencephalic hemorrhage have a normal life expectancy and are not at risk for rebleeding. No restrictions should be imposed on these patients by physicians or health or life insurance companies.

A clinical analysis of twelve cases of ruptured cerebral de novo aneurysms

Formation of cerebral de novo aneurysms (CDNA) is rare, and the pathogenesis remains obscure. In this study, we investigated the factors that contribute to the formation of CDNA and suggest guidelines for following patients treated for cerebral aneurysms. We retrospectively reviewed 2,887 patients treated for intracranial aneurysm at our institute from January of 1976 to December of 2005. Of those patients, 12 were readmitted due to recurrent rupture of CDNA, which was demonstrated by cerebral angiography. We assessed clinical characteristics, such as gender, size and site of rupture, past history, and the time to CDNA rupture. Of the 12 patients, 11 were female and 1 was male, with a mean age at rupture of the first aneurysm of 44.7 years (range: 30-69 years). The mean time between the first episode of subarachnoid hemorrhage (SAH) and the second was 8.9 years (range: 1.0-16.7 years). The most common site of ruptured CDNA was the internal carotid artery (5 patients, 41.7%), followed by basilar artery bifurcation (3 patients, 25.0%). In the remaining 4 patients, rupture occurred in the anterior communicating, middle cerebral, anterior cerebral (A1), or posterior cerebral (P1) arteries. In 5 cases (41.7%), the CDNA occurred contralateral to the initial aneurysm. Eleven patients (91.7%) had a past history of arterial hypertension. There was no history of habitual smoking or alcohol abuse in any of the patients. Eight patients underwent clipping for CDNA and three patients were treated with coiling. One patient who had multiple aneurysms was treated with clipping following intra-aneurysmal coiling. Assessment according to the Glasgow Outcome Scale (GOS) of the patients after the treatment was good in 10 cases (83.3%) and fair in 2 cases (16.7%). Although formation of CDNA after successful treatment of initial aneurysm is rare, several factors may contribute to recurrence. In our study, female patients with a history of arterial hypertension were at higher risk for ruptured CDNA. We recommend follow-up imaging studies every five years after treatment of the initial aneurysm, especially in women and those with a history of arterial hypertension.

Subarachnoid haemorrhage

Subarachnoid haemorrhage accounts for only 5% of strokes, but occurs at a fairly young age. Sudden headache is the cardinal feature, but patients might not report the mode of onset. CT brain scanning is normal in most patients with sudden headache, but to exclude subarachnoid haemorrhage or other serious disorders, a carefully planned lumbar puncture is also needed. Aneurysms are the cause of subarachnoid haemorrhage in 85% of cases. The case fatality after aneurysmal haemorrhage is 50%; one in eight patients with subarachnoid haemorrhage dies outside hospital. Rebleeding is the most imminent danger; a first aim is therefore occlusion of the aneurysm. Endovascular obliteration by means of platinum spirals (coiling) is the preferred mode of treatment, but some patients require a direct neurosurgical approach (clipping). Another complication is delayed cerebral ischaemia; the risk is reduced with oral nimodipine and probably by maintaining circulatory volume. Hydrocephalus might cause gradual obtundation in the first few hours or days; it can be treated by lumbar puncture or ventricular drainage, dependent on the site of obstruction.

Psychosocial impact of finding small aneurysms that are left untreated in patients previously operated on for ruptured aneurysms

OBJECTIVES

In patients with previous subarachnoid haemorrhage (SAH) undergoing follow up screening, the authors assessed the impact of finding but not treating very small aneurysms by comparing quality of life (QOL), anxiety, and depression between patients with a newly detected aneurysm that was left untreated (cases) and patients with a negative screening (controls) as this should be incorporated in the evaluation of effectiveness of screening.

METHODS

In patients with previous SAH undergoing screening for new aneurysms the authors compared QOL (SF-36, EURO-QOL, and a screening related questionnaire), anxiety, and depression (Hospital Anxiety and Depression Scale (HADS)) between cases and controls. Differences in scores on the SF-36, EURO-QOL, and HADS were assessed with Student's t test and differences in proportions of patients with HADS scores in the pathological range and screening related changes with chi2 analysis. The authors powered the study to detect a moderate, clinically relevant difference.

RESULTS

Thirty five cases and 34 controls were included. Trends for health related QOL, anxiety, depression, and consequences in daily life pointed in the same direction of a less favourable situation for cases but all effects were small, and did not reach statistical significance. On the screenings specific questionnaire, cases more often (but not statistically significant) reported changes in daily life.

CONCLUSIONS

The authors found no major or moderate impact on QOL, anxiety, and depression of the awareness of having an untreated aneurysm, which was detected at screening, although most items showed a trend towards more negative effects for cases. Minor effects on individual level cannot be excluded by this study.

Comparison of multislice computerized tomography angiography and digital subtraction angiography in the postoperative evaluation of patients with clipped aneurysms

Object

In this study the accuracy of multislice computerized tomography (MSCT) angiography in the postoperative examination of clip-occluded intracranial aneurysms was compared with that of intraarterial digital subtraction (DS) angiography

Methods

Forty-nine consecutive patients with 60 clipped aneurysms (41 of which had ruptured) were studied with the aid of postoperative MSCT and DS angiography. Both types of radiological studies were reviewed independently by two observers to assess the quality of the images, the artifacts left by the clips, the completeness of aneurysm occlusion, the patency of the parent vessel, and the duration and cost of the examination.

The quality of MSCT angiography was good in 42 patients (86%). Poor-quality MSCT angiograms (14%) were a result of the late acquisition of images in three patients and the presence of clip or motion artifacts in four. Occlusion of the aneurysm on good-quality MSCT angiograms was confirmed in all but two patients in whom a small (2-mm) remnant was confirmed on DS angiograms. In one patient, occlusion of a parent vessel was seen on DS angiograms but missed on MSCT angiograms. The sensitivity and specificity for detecting neck remnants on MSCT angiography were both 100%, and the sensitivity and specificity for evaluating vessel patency were 80 and 100%, respectively (95% confidence interval 29.2–100%). Interobserver agreements were 0.765 and 0.86, respectively. The mean duration of the examination was 13 minutes for MSCT angiography and 75 minutes for DS angiography (p < 0.05). Multislice CT angiography was highly cost effective (p < 0.01).

Conclusions

Current-generation MSCT angiography is an accurate noninvasive tool used for assessment of clipped aneurysms in the anterior circulation. Its high sensitivity and low cost warrant its use for postoperative routine control examinations following clip placement on an aneurysm. Digital subtraction angiography must be performed if the interpretation of MSCT angiograms is doubtful or if the aneurysm is located in the posterior circulation.

Recurrent or new symptomatic cerebral aneurysm after previous treatment

SUMMARY

With the establishment of endovascular coiling as a successful treatment for symptomatic cerebral aneurysms, attention is now being directed at the durability of this treatment. If this is to be accurately done it will be important to understand the causes of symptomatic aneurysm presentation after previous treatment. In order to assess this we undertook a retrospective review, covering the four year period from 2000 to 2004, of all patients re-presenting with a symptomatic saccular aneurysm after previous treatment. Seven patients were identified, six presenting with subarachnoid haemorrhage (SAH) and one with a third cranial nerve palsy. Three patients had incomplete clipping of their aneurysms and all presented within months of their initial treatment. The other four patients presented between five and 20 years after primary treatment and all were felt to have new cerebral aneurysms. Two of these patients had aneurysms develop at the same location as their previously treated lesions, however these were still felt to be new aneurysms rather than re-growth or recurrence because of their morphology. Based on our findings it would appear that development of a new cerebral aneurysm after clipping is more of a risk than aneurysm recurrence from treatment failure. This will need to be considered when evaluating re-presentation after treatment by either coiling or clipping and more importantly, perhaps we should be directing more attention to preventing disease progression rather than treatment failure.

Incidence of Recurrent Subarachnoid Hemorrhage After Clipping for Ruptured Intracranial Aneurysms

Background and Purpose— Because intracranial aneurysms develop during life, patients with subarachnoid hemorrhage (SAH) and successfully occluded aneurysms are at risk for a recurrence. We studied the incidence of and risk factors for recurrent SAH in patients who regained independence after SAH and in whom all aneurysms were occluded by means of clipping.

Methods— From a cohort of patients with SAH admitted between 1985 and 2001, we included those patients who were discharged home or to a rehabilitation facility. We interviewed these patients about new episodes of SAH. We retrieved all medical records and radiographs in case of reported recurrences. If patients had died, we retrieved the cause of death. We analyzed the incidence of and risk factors for recurrent SAH by Kaplan-Meier curves and Cox regression analysis.

Results— Of 752 patients with 6016 follow-up years (mean follow up 8.0 years), 18 had a recurrence. In the first 10 years after the initial SAH, the cumulative incidence of recurrent SAH was 3.2% (95% confidence interval [CI], 1.5% to 4.9%) and the incidence rate 286 of 100 000 patient-years (95% CI, 160 to 472 per 100 000). Risk factors were smoking (hazard ratio [HR], 6.5; 95% CI, 1.7 to 24.0), age (HR, 0.5 per 10 years; 95% CI, 0.3 to 0.8) and multiple aneurysms at the time of the initial SAH (HR, 5.5; 95% CI, 2.2 to 14.1).

Conclusions— After SAH, the incidence of a recurrence within the first 10 years is 22 (12 to 38) times higher than expected in populations with comparable age and sex. Whether this increased risk justifies screening for recurrent aneurysms in patients with a history of SAH requires further study.

Endovascular coiling versus neurosurgical clipping for patients with aneurysmal subarachnoid haemorrhage

BACKGROUND

Patients who have had an aneurysmal subarachnoid haemorrhage (SAH) are at very high risk of rebleeding if the aneurysm is not treated. The standard treatment for several decades has been surgical clipping of the neck of the aneurysm. In recent years, an alternative, the introduction of detachable coils to occlude the aneurysm, has become more common.

OBJECTIVES

To compare the effects of endovascular coiling versus neurosurgical clipping in patients with aneurysmal subarachnoid haemorrhage.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched in February 2005). In addition we searched MEDLINE (1966 to January 2004) and EMBASE (1980 to January 2004), and contacted trialists.

SELECTION CRITERIA

We included randomised trials in which endovascular coiling of aneurysms was compared with neurosurgical clipping in patients with SAH who have proven aneurysm.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed trial quality. Trialists were contacted to obtain missing information.

MAIN RESULTS

We identified three randomised trials: two published and one unpublished. The trials included a total of 2272 patients (range per trial: 20 to 2143 patients). Most of the patients were in good clinical condition and had an aneurysm on the anterior circulation. After one year of follow up, the relative risk (RR) of poor outcome for coiling versus clipping was 0.76 (95% confidence interval (CI) 0.67 to 0.88). The absolute risk reduction was 7% (95% CI 4% to 11%). In the worst-case scenario analysis for poor outcome overall, the relative risk for coiling versus clipping was 0.81 (95% CI 0.70 to 0.92) and the absolute risk reduction was 6% (95% CI 2% to 10%). For patients with anterior circulation aneurysm the relative risk of poor outcome was 0.78 (95% CI 0.68 to 0.90) and the absolute risk decrease was 7% (95% CI 3% to 10%). For those with a posterior circulation aneurysm the relative risk was 0.41 (95% CI 0.19 to 0.92) and the absolute decrease in risk 27% (95% CI 6% to 48%).

AUTHORS' CONCLUSIONS

The evidence comes mainly from one large trial. For patients in good clinical condition with ruptured aneurysms of either the anterior or posterior circulation we have firm evidence that, if the aneurysm is considered suitable for both surgical clipping and endovascular treatment, coiling is associated with a better outcome.

New Detected Aneurysms on Follow-Up Screening in Patients With Previously Clipped Intracranial Aneurysms

Background and Purpose— Patients with a history of aneurysmal subarachnoid hemorrhage may have aneurysms on screening several years after the hemorrhage. For determining the benefits of follow-up screening, it is important to know whether these aneurysms have developed after the hemorrhage or are visible in retrospect, and if so, whether the size has increased.

Methods— Aneurysms were categorized into de novo aneurysms and aneurysms visible in retrospect (already present) with increased or stable size. We studied aneurysm characteristics for these 3 categories: the relation between aneurysm development or enlargement and duration of follow up and the relation between enlargement and initial size of the aneurysm.

Results— In 87 of 495 patients (17.6%), aneurysms were detected; for 51 of these patients with 62 aneurysms, the original catheter or computed tomographic angiogram was available for comparison. Of the 62 aneurysms, 19 were de novo and 43 were visible in retrospect, 10 with increased size and 33 with stable size. De novo aneurysms were mainly ≤5 mm (95%) and located at the middle cerebral artery (63%). For aneurysms visible in retrospect, the most frequent location was the posterior communicating artery (21%). There was no relation between the development of de novo aneurysms or enlargement and the duration of follow-up or between enlargement and the initial size of the aneurysm.

Conclusions— Of aneurysms detected at screening, one third were de novo and two thirds were missed at the time of the initial hemorrhage. One quarter of initially small aneurysms had enlarged during follow-up.

Follow-up screening after subarachnoid haemorrhage: frequency and determinants of new aneurysms and enlargement of existing aneurysms

Intracranial aneurysms have long been considered a once in a lifetime event. Nevertheless, patients who survive after subarachnoid haemorrhage (SAH) may be at risk for new aneurysms. In a cohort of patients with clipped aneurysms, we studied the yield of screening in the years after the SAH and we tried to identify risk factors for formation of new aneurysms as well as for enlargement of aneurysms that were already present at the time of the SAH. We screened 610 patients who had been admitted between 1985 and 2001 for SAH by means of CT-angiography. Risk factors were evaluated by Cox regression analyses. With screening we detected 129 aneurysms in 96 (16%) patients, after a mean interval of 8.9 years. Of these, 24 (19%) were located at the site of the previously ruptured and clipped aneurysm and 105 (81%) at a site remote from the clip site. Of the aneurysms at a remote site 59 could be compared with the initial (CT)-angiogram. Of these, 19 were truly de novo (32%) and 40 (68%) were already visible in retrospect. Of the 53 aneurysms that were followed over time 13 (25%) had enlarged. Risk factors for aneurysm formation and growth were presence of multiple aneurysms at time of SAH (HR 3.2, 95% CI 1.2-8.6), current smoking (HR 3.8, 95% CI 1.5-9.4) and hypertension (HR 2.3, 95% CI 1.1-4.9). These results suggest that intracranial aneurysms should not be considered as a single event in a lifetime but rather as a continuous process. Patients with a previous SAH have a substantial risk for new aneurysm formation and enlargement of untreated aneurysms. Screening these patients might be beneficial, especially in patients with multiple aneurysms, hypertension and a history of smoking. The risks and benefits of screening, however, should be carefully weighed, for example, in a decision model.