History Of Subarachnoid Hemorrhage Research Articles

Mental health, anxiety, and depression in patients with cerebral aneurysms

Aneurysm disease and its treatment can have an adverse impact on mental health, yet the affects of cerebral aneurysms on general mental health, anxiety, and depression are poorly understood. Patients with cerebral aneurysms who were seen at a neurosurgery clinic underwent a structured interview, completed the Hospital Anxiety and Depression Scale and the Medical Outcomes Study 12-item Short Form Health Survey (providing a mental component summary [MCS] score for general mental health), and were assigned functional status scores based on the Glasgow Outcome Scale (GOS), Rankin Scale, and Barthel Index. Rank-order methods were used to assess the relationship between mental health, aneurysm characteristics and history, and functional status. Data were collected in 166 patients (71% women) with a mean age of 53.7 years. Depression was present in 8% of the study population and an anxiety disorder in 17%. Patients with both an unsecured aneurysm and a history of subarachnoid hemorrhage (SAH) tended toward higher anxiety scores (p = 0.086). Higher depression scores were associated with a decreased functional status on the GOS (p = 0.015) and Rankin Scale (p = 0.010). The mean +/- standard deviation adjusted MCS score (37.9 +/- 7.1) was significantly less than that of the US population (p < 0.001). Lower MCS scores were associated with a decreased functional status on the GOS (p = 0.052), Rankin Scale (p < 0.001), and Barthel Index (p = 0.002). Patients with cerebral aneurysms have increased levels of anxiety and depression and poor general mental health. Those who have experienced an SAH and harbor an unsecured cerebral aneurysm demonstrate increased levels of anxiety. A lower functional status in patients with aneurysms is associated with depression and decreased general mental health.

Intrathecal Colistin and Sterilization of Resistant Pseudomonas Aeruginosa Shunt Infection

To report 2 cases of multidrug-resistant (MDR) Pseudomonas aeruginosa meningitis and ventriculo-peritoneal shunt (VPS) infection successfully sterilized with intrathecal colistin 10 mg/day after development of nephrotoxicity associated with intravenous administration. Case 1. A 69-year-old African American woman with a history of subarachnoid hemorrhage and hydrocephalus requiring VPS placement was admitted with VPS infection and meningitis. Cerebrospinal fluid (CSF) cultures revealed MDR P. aeruginosa susceptible only to colistin. Intravenous colistin was initiated but rapidly discontinued due to development of renal dysfunction. Intravenous colistin was the probable cause of the adverse effect. Intrathecal colistin was initiated via an externalized VPS, with subsequent improvement in white blood cell counts in the CSF. Follow-up CSF cultures remained sterile and renal function returned to baseline. Case 2. A 69-year-old white woman with a history of subarachnoid hemorrhage, hydrocephalus, and VPS was transferred from an extended-care facility for management of a VPS infection. CSF cultures revealed MDR P. aeruginosa susceptible only to colistin. Intravenous colistin was initiated but subsequently discontinued due to worsening renal function that, as with the first case, probably correlated with colistin administration and persisted despite dose adjustment. Therapy was changed to intrathecal administration, with subsequent normalization of her CSF white blood cell counts and sterilization of cultures. The limited availability of antibiotics for treatment of highly resistant or MDR gram-negative organisms has prompted clinicians to reconsider the use of older drugs. Prior reports have suggested that intravenous colistin is a potential alternative for treating highly resistant gram-negative central nervous system infections, specifically Acinetobacter, but its use is limited by nephrotoxicity. Our experience suggests that intrathecal colistin is a potentially curative intervention for the treatment of severe MDR P. aeruginosa meningitis and VPS infections in patients in whom intravenous colistin is not an option. Intrathecal use of colistin is a potentially safe, effective, and viable treatment option for MDR P. aeruginosa central nervous system infections when intravenous administration is not feasible.

The Short Form—12 and the measurement of health status in patients with cerebral aneurysms: performance, validity, and reliability

Cerebral aneurysms can affect a patient's health status by rupture and stroke, impingement on neural structures, treatment side effects, or psychological stress. The authors assessed the performance, validity, and reliability of the Short Form-12 (SF-12), a self-administered written survey instrument, to assess health status in patients with cerebral aneurysms. A cohort of 170 patients with cerebral aneurysms who were seen at a neurosurgery clinic underwent structured interviews including measurement of their health statuses (SF-12 physical component summary [PCS] and mental component summary [MCS]), functional status (Glasgow Outcome Scale score, modified Rankin Scale score, and Barthel Index), and mental health (Hospital Anxiety and Depression Scale score). The SF-12 scores were compared with US population norms by performing t-tests with unequal variances. The validity of the SF-12 was assessed by comparing the PCS and MCS scores with each patient's functional status and mental health scores by using rank-order methods. Inter-item reliability was assessed using the Cronbach alpha statistic. Patients with cerebral aneurysms had decreased health status PCS and MCS scores when compared with population norms (p < 0.001 for all). A history of subarachnoid hemorrhage (SAH) (p = 0.006) and previous surgical or endovascular treatment (p = 0.047) was associated with worse PCS scores. The validity of the SF-12 was supported by the relationship between the PCS and MCS scores and the patient's functional status and mental health (p < 0.001 for all). The reliability of the SF-12 was documented by the Cronbach alpha statistic (alpha = 0.76). Patients with cerebral aneurysms have a diminished physical and mental health status as measured using the SF-12. The presence of SAH and aneurysm treatment are associated with a worse physical health status. The SF-12 is a valid and reliable instrument for measuring health status in patients with cerebral aneurysms.

Risk–benefit analysis of the treatment of unruptured intracranial aneurysms

Objectives: To determine under what circumstances repair of unruptured intracranial aneurysms may be beneficial. Methods: A life expectancy analysis of patients with unruptured aneurysms with and without repair based on...

Patients With Small, Asymptomatic, Unruptured Intracranial Aneurysms and No History of Subarachnoid Hemorrhage Should Be Treated Conservatively

It is foolhardy to remove from consideration of treatment any aneurysm solely because its maximal size is <10 mm or 7 mm. Annually, ≥15 000 American patients have subarachnoid hemorrhage (SAH) from aneurysms with a maximum diameter <7 mm and consequently experience irreparable morbidity and severe mortality. The majority of their aneurysms were, of course, unruptured, single, asymptomatic, and even smaller at some point before rupture. If the rupture rates for <10-mm aneurysms in International Study of Unruptured Intracranial Aneurysm (ISUIA) I1 or <7 mm in ISUIA II2 are used with the known number of ruptured aneurysms of these sizes admitted each year to calculate the prevalence of such small aneurysms in American adults, there is an unbelievably high result: in the range of 7% to 14%. Previous best estimates of prevalence on the basis of retrospective and prospective, radiological and pathological data have been ≈2% for all sizes of aneurysms and for those <10 mm, less than 1%. In autopsy studies, unruptured aneurysms have not outnumbered ruptured ones; the reverse is the case.3 Between ISUIA I1 and ISUIA II,2 the rupture rate …

Pathogenesis, Natural History, and Treatment of Unruptured Intracranial Aneurysms

Unruptured intracranial aneurysms (UIAs) are a major public health issue. These lesions have become increasingly recognized in recent years with the advent of advanced cerebral imaging techniques. Epidemiological evidence from multiple sources suggests that most intracranial aneurysms do not rupture. Therefore, it is desirable to identify which UIAs are at greatest risk of rupture when considering which to repair. It is important to compare size-, site-, and group-specific natural history rates with size-, site-, and age-specific morbidity and mortality associated with UIA repair because increased natural history risk often is associated with increased risk of aneurysm repair. Patient age is crucial in decision making because of its major effect on operative morbidity and mortality; however, it does not substantially affect natural history. The effect of age is most notable in patients about 50 years of age and older for open surgery and about 70 years of age and older for endovascular procedures. In general, rupture risk is lowest for patients in asymptomatic group 1 (no history of subarachnoid hemorrhage) with UIAs less than 7 mm in diameter in the anterior circulation. Surgical morbidity and mortality are most favorable for asymptomatic patients younger than 50 years who have UIAs less than 24 mm in diameter in the anterior circulation and no history of ischemic cerebrovascular disease. Endovascular morbidity and mortality may be less age dependent, and this could favor endovascular procedures, particularly in patients aged 50 to 70 years. An important issue is determining immediate vs long-term risk regarding treatment effectiveness and durability. This issue emphasizes the importance of long-term follow-up in patients after surgical and endovascular procedures.

Early vasospasm on admission angiography in patients with aneurysmal subarachnoid hemorrhage is a predictor for in-hospital complications and poor outcome.

Early vasospasm (EVSP), defined here as arterial narrowing seen on diagnostic angiography within the first 48 hours of aneurysmal rupture, is a rarely reported and poorly defined phenomenon in patients with subarachnoid hemorrhage (SAH). The purpose of this study was to characterize EVSP in a large database of such patients. We analyzed the relationship of EVSP to clinical characteristics, in-hospital complications, and outcome at 3 months among 3478 patients entered into 4 prospective, randomized, double-blind, placebo-controlled trials of tirilazad conducted in neurosurgical centers around the world between 1991 and 1997. Three hundred thirty-nine (10%) of 3478 patients had EVSP. EVSP was significantly more likely in patients with poor neurological grade on admission, history of SAH, intracerebral hematoma, larger aneurysm, thick SAH on cranial computed tomography, and intraventricular hemorrhage. EVSP was not associated with delayed cerebral vasospasm. After adjustment for differences in admission characteristics, EVSP was associated with cerebral infarction (adjusted odds ratios [OR]=1.51; 95% CI, 1.18 to 1.94; P=0.001), neurological worsening (OR=1.41; 95% CI, 1.10 to 1.81; P=0.007), and unfavorable outcome (OR=1.51; 95% CI, 1.15 to 2.00; P=0.003). In addition, there was a trend for patients with increasingly severe EVSP to have unfavorable outcome (OR=1.84 for mild and OR=2.66 for moderate/severe EVSP). EVSP was seen in 10% of SAH patients and was predictive of cerebral infarction and neurological worsening as well as unfavorable outcome at 3 months. EVSP was not associated with late vasospasm. EVSP may be as important as delayed vasospasm in predicting complications and long-term morbidity in SAH patients.

Endovascular treatment of cerebrovascular disease.

This review summarizes recent advances in endovascular therapy for cerebrovascular disease. For ruptured aneurysms, the only large, randomized, controlled trial comparing surgical and endovascular treatment (the International Subarachnoid Aneurysm Trial) resulted in a significant reduction in death or dependency at 1 year, compared with surgery, providing sound evidence that coiling should be the treatment of first choice. Data from the International Study of Unruptured Intracranial Aneurysms demonstrated that treatment of unruptured anterior circulation aneurysms of under 7 mm with no history of subarachnoid hemorrhage is not justified. Embolization of arteriovenous malformations, as sole therapy, is curative only in a small percentage of cases, but can be part of a multimodal approach for reducing arteriovenous malformation size prior to surgery or radiotherapy. Partial treatment of complex arteriovenous malformations may be more dangerous than no treatment. Protection devices can reduce complication rates in carotid artery stenting, but scientific evidence is still lacking. Until the results of comparative trials are available, carotid artery stenting is indicated only in selected patients. Angioplasty and stenting of intracranial arterosclerotic disease is feasible but remains a high-risk procedure, indicated only in highly selected patients. In acute stroke therapy, new thrombolytics and clot-retrieval devices may result in better recanalization rates. Advances in endovascular therapy have occurred in all areas of cerebrovascular disease. To obtain maximal patient benefit, endovascular treatment should be performed as an interdisciplinary approach in high-volume centers. Importantly, long-term follow-up review is necessary to clarify the overall role of endovascular treatment in the management of cerebrovascular disease.

Screening for intracranial aneurysms in autosomal dominant polycystic kidney disease.

Screening patients with autosomal dominant polycystic kidney disease (ADPKD) for asymptomatic intracranial aneurysms has been proposed as a method of reducing the morbidity and mortality associated with aneurysm rupture. However, recent studies have shown lower spontaneous rupture rates of small aneurysms and higher risks of significant complications with interventions than previously reported. Risk-benefit analysis has not demonstrated any benefit of screening ADPKD patients without a history of subarachnoid haemorrhage (SAH) for intracranial aneurysms, and has suggested that screening might cause harm.

Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment

The management of unruptured intracranial aneurysms is controversial. Investigators from the International Study of Unruptured Intracranial Aneurysms aimed to assess the natural history of unruptured intracranial aneurysms and to measure the risk associated with their repair. Centres in the USA, Canada, and Europe enrolled patients for prospective assessment of unruptured aneurysms. Investigators recorded the natural history in patients who did not have surgery, and assessed morbidity and mortality associated with repair of unruptured aneurysms by either open surgery or endovascular procedures. 4060 patients were assessed-1692 did not have aneurysmal repair, 1917 had open surgery, and 451 had endovascular procedures. 5-year cumulative rupture rates for patients who did not have a history of subarachnoid haemorrhage with aneurysms located in internal carotid artery, anterior communicating or anterior cerebral artery, or middle cerebral artery were 0%, 2. 6%, 14 5%, and 40% for aneurysms less than 7 mm, 7-12 mm, 13-24 mm, and 25 mm or greater, respectively, compared with rates of 2 5%, 14 5%, 18 4%, and 50%, respectively, for the same size categories involving posterior circulation and posterior communicating artery aneurysms. These rates were often equalled or exceeded by the risks associated with surgical or endovascular repair of comparable lesions. Patients' age was a strong predictor of surgical outcome, and the size and location of an aneurysm predict both surgical and endovascular outcomes. Many factors are involved in management of patients with unruptured intracranial aneurysms. Site, size, and group specific risks of the natural history should be compared with site, size, and age-specific risks of repair for each patient.

Incidence and Clinical Hallmark of Brain Tumors and Cerebral Aneurysms on Repeated Brain Check-up.

Background The incidence of brain tumors or cerebral aneurysms remains unknown on repeated brain check-up.Purpose We studied the incidence of brain tumors or cerebral aneurysms in large number of individuals who reccceived brain checkup more than twice in PL Tokyo Health Care Center, Japan.Method In our center, 9, 538 participants received brain check-up between August 1995 and July 2002. We analyzed 2, 175 participants (1, 598 men and 577 women) who had brain and physical check-ups more than 2 times. Mean age of subjects was 53.4 (SD 10.4) years in all, 53.1 (SD 10.3) years in men and 54.2 (SD 10.6) years in women. Subjects who were diagnosed as brain tumors or cerebral aneurysms on the first brain check-up were excluded. Brain check-up was produced by 1.5-tesla superconducting system (Stratis II, Hitachi Medical, Japan) . Conventional magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) using three-dimension time-of-flight sequence were undertaken in all subjects. The incidence and the clinical features of brain tumors or cerebral aneurysms were studied.Results The frequency of repeated brain check-up was 22.8%. The intervals between brain check-ups were 277 to 728 days. The times of brain check-up were two to sex. The analysis of brain tumor was diagnosed as meningioma in one woman. The incidence of brain tumors was 0.05% in total subjects and 0.17% in women. The duration between the first and the 2nd brain check-up was one year in this case. Cerebral aneurysms were seen in 6 subjects (2 men and 4 women) . All subjects had no clinical symptoms without a family history of subarachnoid hemorrhage. The total number of aneurysms was 8. Aneurysms were located in the internal carotid artery (n=2), the anterior cerebral arteries (n=3), the middle cerebral artery (n=3) and the basilar artery (n=1) . Two women had two aneurysms. The incidence of aneurysms was 0.28% in total subjects, 0.13% in men and 0.69% in women. The mean age of subjects with aneurysms was 57.7 (SD 6.7) years in all, 64.0 (SD 6.7) years in men, and 54.5 (SD 5.4) years in women. The interval between the first and the 2nd brain check-up was one to five years and the mean duration was 3.0 years (SD 1.7) in 6 subjects with aneurysms. The prognosis was excellent in those five subjects. Subarachnoid hemorrhage occurred in one woman with multiple aneurysms although we strongly recommended neurosurgical procedures for enlarging aneurysms.Conclusion The underdiagnosis of brain tumors and cerebral aneurysms on the first brain check-up contributed to sizes and portions of lesions, radiological technique and reviewers of neuroim-ages. To make the early and correct diagnosis of both fatal diseases, we should compare between the initial and repeated data, including resource imaging of MRA. Radiological technicians always investigate the monitor of MRI and MRA. Cooperation with neurological reviewers and radiological technicians is important to make the early diagnosis of brain tumors and cerebral aneurysms. Our stud-ies indicate that brain check-up should be repeated within a few years, in order to discover asymptomatic brain tumors and unrup-tured aneurysms.

Intracranial saccular aneurysm enlargement determined using serial magnetic resonance angiography.

The goal of this study was to determine the frequency of enlargement of unruptured intracranial aneurysms by using serial magnetic resonance (MR) angiography and to investigate whether aneurysm characteristics and demographic factors predict changes in aneurysm size. A retrospective review of MR angiograms obtained in 57 patients with 62 unruptured, untreated saccular aneurysms was performed. Fifty-five of the 57 patients had no history of subarachnoid hemorrhage. The means of three measurements of the maximum diameters of these lesions on MR source images defined the aneurysm size. The median follow-up period was 47 months (mean 50 months, range 17-90 months). No aneurysm ruptured during the follow-up period. Four patients (7%) harbored aneurysms that had increased in size. No aneurysms smaller than 9 mm in diameter grew larger, whereas four (44%) of the nine aneurysms with initial diameters of 9 mm or larger increased in size. Factors that predicted aneurysm growth included the size of the lesion (p < 0.001) and the presence of multiple lobes (p = 0.021). The location of the aneurysm did not predict an increased risk of enlargement. Patients with medium-sized or large aneurysms and patients harboring aneurysms with multiple lobes may be at increased risk for aneurysm growth and should be followed up with MR imaging if the aneurysm is left untreated.

Unruptured Intracranial Aneurysms and Multiple Aneurysms

Surgery on unruptured intracranial aneurysms (UIAs) could be a good strategy for prevention of haemorrhage, but management decisions require an accurate assessment of the risks of various treatment options, compared with the natural history of subarachnoid haemorrhage (SAH). The International Study for Unruptured Aneurysms (ISUIA) showed that the natural history is different for patients with UIAs who have not experienced SAH, than it is for patients with a history of prior SAH due to a separate aneurysm, in whom the risk is increased. The size of the UIAs is the best predictor of future rupture and the site can also be. The role of elective neuroradiological screening is the subject of discussion. In fact, the possibility of treatment should be considered on the basis of the patient's age and clinical status. Factors that favour surgery include a young patient with a long life expectancy, previously ruptured aneurysms, a familiarity, large and symptomatic aneurysms and low risk of treatment. The role of endovascular treatment is also discussed.

Endoscopic third ventriculostomy in patients with cerebrospinal fluid infection and/or hemorrhage.

In this study the authors evaluate the safety, efficacy, and indications for endoscopic third ventriculostomy (ETV) in patients with a history of subarachnoid hemorrhage or intraventricular hemorrhage (IVH) and/or cerebrospinal fluid (CSF) infection. The charts of 101 patients from seven international medical centers were retrospectively reviewed; 46 patients had a history of hemorrhage, 42 had a history of CSF infection, and 13 had a history of both disorders. All patients experienced third ventricular hydrocephalus before endoscopy. The success rate for treatment in these three groups was 60.9, 64.3, and 23.1%, respectively. The follow-up period in successfully treated patients ranged from 0.6 to 10 years. Relatively minor complications were observed in 15 patients (14.9%), and there were no deaths. A higher rate of treatment failure was associated with three factors: classification in the combined infection/hemorrhage group, premature birth in the posthemorrhage group, and younger age in the postinfection group. A higher success rate was associated with a history of ventriculoperitoneal (VP) shunt placement before ETV in the posthemorrhage group, even among those who had been born prematurely, who were otherwise more prone to treatment failure. The 13 premature infants who had suffered an IVH and who had undergone VP shunt placement before ETV had a 100% success rate. The procedure was also successful in nine of 10 patients with primary aqueductal stenosis. Patients with obstructive hydrocephalus and a history of either hemorrhage or infection may be good candidates for ETV, with safety and success rates comparable with those in more general series of patients. Patients who have sustained both hemorrhage and infection are poor candidates for ETV, except in selected cases and as a treatment of last resort. In patients who have previously undergone shunt placement posthemorrhage, ETV is highly successful. It is also highly successful in patients with primary aqueductal stenosis, even in those with a history of hemorrhage or CSF infection.

Aneurysm observation versus intervention: A literature review

Aneurysmal subarachnoid hemorrhage (SAH) is a devastating illness that affects persons at the peaks of their lives. The 1990s witnessed rapid growth in noninvasive vascular imaging technologies, which allowed safe diagnosis of unruptured saccular intracranial aneurysms. Presently, it is unclear who will benefit from screening. Mass screening is neither feasible nor cost-effective. The current literature suggests that persons in a family with two or more relatives with a history of SAH are most likely to benefit from screening. Individuals with a history of SAH, with aneurysms greater than 10 mm in diameter or with symptomatic aneurysms are clearly at increased risk for SAH. These aneurysms should be treated, though the method of treatment remains open to question. Treatment of older patients or those with smaller aneurysms has been modeled by decision analysis, but has yet to be verified in a prospective clinical trial. Future directions for aneurysm management are explored. [Neurol Res 2002; 24: S84-S95]

Gender Differences in Unruptured Intracranial Aneurysm Formation: Risk Factors and Characteristics

P151 The International Study of Unruptured Intracranial Aneurysms (ISUIA) Background and Purpose: There are few data available defining gender-based differences in intracranial aneurysm (UIA) risk factors and occurrence. The ISUIA provides a unique setting for evaluating these issues. Methods: Fifty-three centers in the ISUIA entered 5,669 patients with UIA. 1531 patients are part of a retrospective follow-up of unoperated UIA between 1970 and 1991. Another 4,138 comprise a prospective cohort. Half (58%) of this group are operated and 42% are unnoperated. Data were collected regarding history of subarachnoid hemorrhage (SAH) and factors including characteristics of the UIA, family history of stroke, cigarette smoking and many other demographic and medical history. Results: Combined analysis of these two cohorts revealed that women had a UIA 3 times more frequently than men (75% vs. 25%). Women had more multiple aneurysms than men did (52% vs. 42%; p=0.001). Women had a higher proportion of cavernous and internal carotid artery UIAs (46.5%) while the men more often had anterior and middle cerebral artery UIAs (54.5%), p&lt;0.001. Women had an arteriovenous malformation less frequently than men did (1.6% vs. 3.7%; p=0.001). Cigarette use was less prevalent in women than men (69% vs. 76%; p=0.001) and alcohol use was lower in women than men (12.3% vs. 29.8%; p=0.001). Women were more likely to be hypertensive, (40.3% vs. 36.2%; p=0.02) and had vascular headache more than men, (27.3% vs. 16.9%; p=0.001). Age at diagnosis of UIA and family history of aneurysm, SAH, or indeterminate hemorrhages were similar for men and women. Women in Group 1 (UIA, no prior SAH) more often used oral contraceptives and estrogen replacement therapy than women in Group 2 (UIA, prior SAH from a second aneurysm). Also, Group 1 women more often had a history of hypertension. Women in Group 2 used cigarettes, alcohol and stimulants and had a history of vascular headache more often. Conclusions: Women are more likely to harbor UIA than men. Aneurysm characteristics such as location and multiplicity may differ, between genders. Selected risk factors for aneurysm formation may explain these.

Treatment strategy for patients with unruptured intracranial aneurysms.

The increased sensitivity of neuroimaging techniques has enabled the more frequent diagnosis of unruptured aneurysms. Because the most devastating complication of an unruptured aneurysm is subarachnoid hemorrhage, it has been considered desirable to treat these aneurysms before they rupture. However, the optimal treatment strategy for patients with unruptured aneurysms remains controversial. The management decision requires knowledge of the natural history and an accurate assessment of the risks related to various treatment options. On December 10, 1998 the New England Journal of Medicine published an article by the International Study of Unruptured Intracranial Aneurysms Investigators. The study retrospectively assessed the natural history of unruptured aneurysms in 1449 patients; in addition, treatment-related mortality and morbidity were examined in a prospective cohort of 1172 patients. The major finding was that the rate of rupture for aneurysms smaller than 10 mm in diameter in patients with no history of subarachnoid hemorrhage was 0.05% per year, and that the mortality and morbidity associated with surgery greatly exceeded the risk of rupture in such patients. This report has generated tremendous controversy in the treatment of unruptured aneurysms and has influenced our decision making. The results of this study are critically analyzed and potential flaws presented. To develop recommendations for treatment, the literature was reviewed. The conclusion of this search is that there is insufficient evidence to recommend a standard of management. Therapeutic guidelines are provided, particularly for patients with small incidental aneurysms and no history of subarachnoid hemorrhage.

Estimate of the maximum time interval between formation of cerebral aneurysm and rupture

The recent publication of the results of the international study on unruptured intracranial aneurysms highlighted a paradox: there do not seem to be enough unruptured aneurysms in the population to...

Natural history of unruptured intracranial aneurysms

Therapeutic decisions regarding the management of patients with unruptured intracranial aneurysms ultimately involve consideration of the natural history of these lesions as well as the morbidity and mortality associated with their repair. Available evidence regarding the natural history of unruptured intracranial aneurysms suggests low overall rupture rates with relatively higher rates among patients with unruptured aneurysms and a history of subarachnoid hemorrhage from a separate aneurysm as opposed to patients with no history of subarachnoid hemorrhage. Among patients with no subarachnoid hemorrhage, aneurysmal size and location are independent predictors of future rupture. Among patients with prior subarachnoid hemorrhage, aneurysmal location independently predicts future rupture.

Risk analysis of treatment of unruptured aneurysms

OBJECTIVESTo calculate the expected number of life-years saved by surgical treatment of unruptured intracranial aneurysms at ages over 20 years.METHODSAn actuarial risk analysis of the treatment of unruptured intracranial aneurysms...