Intrinsic, Transitional, and Extrinsic Morphological Factors Associated With Rupture of Intracranial Aneurysms

Neurosurgery ◽  
2015 ◽  
Vol 77 (3) ◽  
pp. 433-442 ◽  
Author(s):  
Allen L. Ho ◽  
Ning Lin ◽  
Kai U. Frerichs ◽  
Rose Du

Abstract BACKGROUND: As diagnosis and treatment of unruptured intracranial aneurysms continues to increase, management principles remain largely based on size. This is despite mounting evidence that aneurysm location and other morphologic variables could play a role in predicting overall risk of rupture. Morphological parameters can be divided into 3 main groups, those that are intrinsic to the aneurysm, those that are extrinsic to the aneurysm, and those that involve both the aneurysm and surrounding vasculature (transitional). OBJECTIVE: We present an evaluation of intrinsic, transitional, and extrinsic factors and their association with ruptured aneurysms. METHODS: Using preoperative computed tomographic angiography, we generated 3-dimensional models of aneurysms and their surrounding vasculature with Slicer software. Using univariate and multivariate analyses, we examined the association of intrinsic, transitional, and extrinsic aspects of aneurysm morphology with rupture. RESULTS: Between 2005 and 2013, 227 cerebral aneurysms in 4 locations were evaluated/treated at a single institution, and computed tomographic angiographies of 218 patients (97 unruptured and 130 ruptured) were analyzed. Ruptured aneurysms analyzed were associated with clinical factors of absence of multiple aneurysms and history of no prior rupture, and morphologic factors of greater aspect ratio. On multivariate analysis, aneurysm rupture remained associated with history of no prior rupture, greater flow angle, greater daughter-daughter vessel angle, and smaller parent-daughter vessel angle. CONCLUSION: By studying the morphology of aneurysms and their surrounding vasculature, we identified several parameters associated with ruptured aneurysms that include intrinsic, transitional, and extrinsic factors of cerebral aneurysms and their surrounding vasculature.

2021 ◽  
pp. 77-80
Author(s):  
Katarzyna Wójtowicz ◽  
Przemysław Kunert ◽  
Łukasz Przepiórka ◽  
Andrzej Marchel

<b><i>Introduction:</i></b> The timing of treatment remains unresolved for patients with unruptured intracranial aneurysms (UIAs) and headaches, particularly when the pain is short term, localized, and related to the aneurysm site. We lack evidence to support the notion that when a headache accompanies an aneurysm, it elevates the risk of rupture. <b><i>Results:</i></b> We describe 2 cases of fatal subarachnoid hemorrhage in patients with a history of headache and known aneurysms. Both of these patients had good indications for treatment: a young age and an aneurysm &#x3e;7 mm, and both were qualified for elective surgery. However, both patients died of fatal aneurysm ruptures before the planned surgery. <b><i>Conclusion:</i></b> These cases suggested that treatment should be started as soon as possible, when a UIA is diagnosed based on a short-term period of severe headaches or when a UIA is observed and then severe headaches appear. There is no straightforward guideline for treatment timing in these patients. However, in this era of UIAs, the significance of sentinel headaches should be reevaluated. Given the incidence of headaches in the general population and the very low risk of aneurysm rupture, there may be a tendency to neglect the role of headache as a possible warning sign.


2006 ◽  
Vol 104 (2) ◽  
pp. 188-194 ◽  
Author(s):  
Han Soo Chang

Object Despite recent publications of large-scale study data, controversy over the management of unruptured cerebral aneurysms continues. The low rupture rates in the International Study of Unruptured Intracranial Aneurysms (ISUIA) apparently contradicted surgeons’ experiences with ruptured aneurysms. In the present study, based on data from the ISUIA, a mathematical model describing the natural history of cerebral aneurysms was developed. With this model, the author aimed to examine the validity of data from the ISUIA and to provide a better treatment guideline for unruptured aneurysms. Methods The author made a computer simulation of the natural history of cerebral aneurysms that was used to calculate such figures as the prevalence of unruptured aneurysms, incidence of subarachnoid hemorrhage (SAH), and age and size distribution of both unruptured and ruptured aneurysms. The lifetime lesion rupture probability for individual patients with various ages and aneurysm sizes was also computed, thereby providing a useful index to help patients in the medical decision-making process. The computer model produced a sample of unruptured aneurysms in the general population with a prevalence of 4.2% and a median diameter of 5.8 mm. These unruptured aneurysms—affected by the rupture rate reported in the ISUIA—had a yearly SAH incidence of 19.6 per 100,000 persons. The median diameter of these aneurysms was 9.4 mm. Conclusions Findings in the present study validated the results of the ISUIA by showing that the seemingly low rupture rates could explain the statistical data for ruptured aneurysms. With the featured model, the author calculated the lifetime probability of lesion rupture—a useful measure for deciding on the optimal treatment for unruptured aneurysms.


2013 ◽  
Vol 19 (1) ◽  
pp. 43-48 ◽  
Author(s):  
K. Wang ◽  
Y. Sun ◽  
A-M. Li

Despite experience and technological improvements, stent-assisted coiling for intracranial aneurysms still has inherent risks. We evaluated peri-procedural morbidity and mortality associated with stent-assisted coiling for intracranial aneurysms. Patients with cerebral aneurysms that were broad-based (>4 mm) or had unfavorable dome/neck ratios (<1.5) were enrolled in this study between February and November 2011 at our center. Aneurysms were treated with the self-expanding neurovascular stents with adjunctive coil embolization. Seventy-two consecutive patients (27 men and 45 women; 22–78 years of age; mean age, 52.8 years) underwent 13 procedures for 13 ruptured aneurysms and 64 procedures for 73 unruptured aneurysms. Nine [11.7%, 95% CI(4.5%–18.9%)] procedure-related complications occurred: one and eight with initial embolization of ruptured and unruptured aneurysms, respectively. Complications included six acute in-stent thromboses, one spontaneous stent migration, one post-procedural aneurysm rupture, and one perforator occlusion. Three complications had no neurologic consequences. Two caused transient neurologic morbidity, two persistent neurologic morbidity, and two death. Procedure-related neurologic morbidity and mortality rates, respectively, were as follows: overall, 5.2% (95%CI, 0.2%–10.2%) and 2.6% (95%CI, 0%–6.2%); ruptured aneurysms, 7.7% (95%CI, 0%–36%) and 0% (95%CI, 0%–25%); unruptured aneurysms, 4.7% (95%CI, 0%–9.9%) and 3.1% (95%CI, 0%–7.3%). Combined procedure-related morbidity and mortality rates for ruptured and unruptured aneurysms were 7.7% (95%CI, 1.7%–13.7%) and 7.8% (95%CI, 1.8%–13.8%), respectively. Stent-assisted coiling is an attractive option for intracranial aneurysms. However, stent-assisted coiling for unruptured aneurysms is controversial for its comparable risk to natural history.


2020 ◽  
Vol 132 (1) ◽  
pp. 94-97 ◽  
Author(s):  
Tiziano Tallarita ◽  
Thomas J. Sorenson ◽  
Lorenzo Rinaldo ◽  
Gustavo S. Oderich ◽  
Thomas C. Bower ◽  
...  

OBJECTIVEConcomitant unruptured intracranial aneurysms (UIAs) are present in patients with carotid artery stenosis not infrequently and result in unique management challenges. Thus, we investigated the risk of rupture of an aneurysm after revascularization of a carotid artery in a contemporary consecutive series of patients seen at our institution.METHODSData from patients who underwent a carotid revascularization in the presence of at least one concomitant UIA at our institution from 1991 to 2018 were retrospectively reviewed. Patients were evaluated for the incidence of aneurysm rupture within 30 days (early period) and after 30 days (late period) of carotid revascularization, as well as for the incidence of periprocedural complications from the treatment of carotid stenosis and/or UIA.RESULTSOur study included 53 patients with 63 concomitant UIAs. There was no rupture within 30 days of carotid revascularization. The overall risk of rupture was 0.87% per patient-year. Treatment (coiling or clipping) of a concomitant UIA, if pursued, could be performed successfully after carotid revascularization.CONCLUSIONSCarotid artery revascularization in the setting of a concomitant UIA can be performed safely without an increased 30-day or late-term risk of rupture. If indicated, treatment of the UIA can take place after the patient recovers from the carotid procedure.


2008 ◽  
Vol 108 (5) ◽  
pp. 1052-1060 ◽  
Author(s):  
Seppo Juvela ◽  
Matti Porras ◽  
Kristiina Poussa

Object The authors conducted a study to investigate the long-term natural history of unruptured intracranial aneurysms and the predictive risk factors determining subsequent rupture in a patient population in which surgical selection of cases was not performed. Methods One hundred forty-two patients with 181 unruptured aneurysms were followed from the 1950s until death or the occurrence of subarachnoid hemorrhage or until the years 1997 to 1998. The annual and cumulative incidence of aneurysm rupture as well as several potential risk factors predictive of rupture were studied using life-table analyses and Cox's proportional hazards regression models including time-dependent covariates. The median follow-up time was 19.7 years (range 0.8–38.9 years). During 2575 person-years of follow up, there were 33 first-time episodes of hemorrhage from previously unruptured aneurysms, for an average annual incidence of 1.3%. In 17 patients, hemorrhage led to death. The cumulative rate of bleeding was 10.5% at 10 years, 23% at 20 years, and 30.3% at 30 years after diagnosis. The diameter of the unruptured aneurysm (relative risk [RR] 1.11 per mm in diameter, 95% confidence interval [CI] 1–1.23, p = 0.05) and patient age at diagnosis inversely (RR 0.97 per year, 95% CI 0.93–1, p = 0.05) were significant independent predictors for a subsequent aneurysm rupture after adjustment for sex, hypertension, and aneurysm group. Active smoking status at the time of diagnosis was a significant risk factor for aneurysm rupture (RR 1.46, 95% CI 1.04–2.06, p = 0.033) after adjustment for size of the aneurysm, patient age, sex, presence of hypertension, and aneurysm group. Active smoking status as a time-dependent covariate was an even more significant risk factor for aneurysm rupture (adjusted RR 3.04, 95% CI 1.21–7.66, p = 0.02). Conclusions Cigarette smoking, size of the unruptured intracranial aneurysm, and age, inversely, are important factors determining risk for subsequent aneurysm rupture. The authors conclude that such unruptured aneurysms should be surgically treated regardless of their size and of a patient's smoking status, especially in young and middle-aged adults, if this is technically possible and if the patient's concurrent diseases are not contraindications. Cessation of smoking may also be a good alternative to surgery in older patients with small-sized aneurysms.


2004 ◽  
Vol 101 (6) ◽  
pp. 1018-1025 ◽  
Author(s):  
Luigi Pentimalli ◽  
Andrea Modesti ◽  
Andrea Vignati ◽  
Enrico Marchese ◽  
Alessio Albanese ◽  
...  

Object. Mechanisms involved in the rupture of intracranial aneurysms remain unclear, and the literature on apoptosis in these lesions is extremely limited. The hypothesis that apoptosis may reduce aneurysm wall resistance, thus contributing to its rupture, warrants investigation. The authors in this study focused on the comparative evaluation of apoptosis in ruptured and unruptured intracranial aneurysms. Peripheral arteries in patients harboring the aneurysms and in a group of controls were also analyzed. Methods. Between September 1999 and February 2002, specimens from 27 intracranial aneurysms were studied. In 13 of these patients apoptosis was also evaluated in specimens of the middle meningeal artery (MMA) and the superficial temporal artery (STA). The terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling technique was used to study apoptosis via optical microscopy; electron microscopy evaluation was performed as well. Apoptotic cell levels were related to patient age and sex, aneurysm volume and shape, and surgical timing. Significant differences in apoptosis were observed when comparing ruptured and unruptured aneurysms. High levels of apoptosis were found in 88% of ruptured aneurysms and in only 10% of unruptured lesions (p < 0.001). Elevated apoptosis levels were also detected in all MMA and STA specimens obtained in patients harboring ruptured aneurysms, whereas absent or very low apoptosis levels were observed in MMA and STA specimens from patients with unruptured aneurysms. A significant correlation between aneurysm shape and apoptosis was found. Conclusions. In this series, aneurysm rupture appeared to be more related to elevated apoptosis levels than to the volume of the aneurysm sac. Data in this study could open the field to investigations clarifying the causes of aneurysm enlargement and rupture.


2020 ◽  
Vol 1 (4) ◽  
Author(s):  
Kashif Majeed ◽  
Srikanth R Boddu ◽  
Joseph Carnevale ◽  
Elif Ezgi Cenberlitas ◽  
Nicholas Williams ◽  
...  

Abstract BACKGROUND To stratify the risk of aneurysmal rupture, size remains the primary criterion as proposed by 2 ISUIA (International Study of Unruptured Intracranial Aneurysms) trials that recommend the observation of ≤7 mm aneurysms because of their low propensity to rupture. These recommendations are controversial, given the severe outcomes following hemorrhage. OBJECTIVE To retrospectively assess whether size correlates with aneurysmal rupture, and to analyze outcomes of endovascular and microsurgical procedures. METHODS All aneurysms presenting between 2016 and 2019 were reviewed. Age, gender, comorbidities, ruptured status, modes of treatment, and their outcomes were noted. Regression analysis was performed to correlate size with rupture. The type of intervention was based on clinical and aneurysmal characteristics and the likelihood of obliteration. RESULTS Of the 668 aneurysms, 116 had ruptured. In size groups 0 to 6 mm,  7 to 12 mm,  13 to 18 mm,  18 to 24 mm, and giant, the ruptured aneurysms were 60.3%, 30.2%, 1.7%, 0.9%, and 6.9%, respectively. The majority (423) were managed endovascularly, of which 84 (19.9%) were ruptured. A total of 97 (14.5%) underwent clipping, of which 31 were ruptured. The mean modified Rankin Scale for both treated groups was zero. One death in each group and a single brainstem stroke in the coiled group were noted. A total of 139 were followed, of which none had ruptured. The mean modified Raymond-Roy classification for endovascular therapy was 1.1, with 380 completely occluded; 15 had a score of 2, and 28 of score 3. CONCLUSION The ruptured aneurysms were mostly smaller than reported previously. Surgical clipping was at equipoise with endovascular treatments. Further studies to correlate aneurysmal characteristics to the risk of rupture are needed.


2019 ◽  
Vol 10 ◽  
pp. 164
Author(s):  
Taro Yanagawa ◽  
Yoichi Harada ◽  
Toru Hatayama ◽  
Takuji Kono

Background: The annual rupture rate of small unruptured intracranial aneurysms (UIAs) <5 mm is generally low; further, small UIAs are often treated conservatively. While the growth of aneurysms during follow-up is associated with a high risk of rupture, the urgency for surgical treatment of asymptomatic enlarged UIAs remains controversial. We experienced two patients in whom UIAs ruptured shortly after asymptomatic growth during follow-up. Case Description: A 1-mm right middle cerebral artery aneurysm was incidentally found in a 63-year-old woman. Preventive surgery was planned because the aneurysm grew rapidly; however, the aneurysm ruptured preoperatively. A 68-year-old woman had a small (4 mm) aneurysm at the left internal carotid-posterior communicating artery. The aneurysm grew rapidly after many years. Several hours after magnetic resonance imaging was performed, she presented to the hospital with loss of consciousness, and a diagnosis of subarachnoid hemorrhage due to the ruptured aneurysm was made. Conclusion: UIAs that rapidly increase during follow-up may be regarded as impending ruptured aneurysms.


2019 ◽  
Vol 26 (1) ◽  
pp. 45-54 ◽  
Author(s):  
Jens J Froelich ◽  
Nicholas Cheung ◽  
Johan AB de Lange ◽  
Jessica Monkhorst ◽  
Michael W Carr ◽  
...  

Objective Incomplete aneurysm occlusions and re-treatment rates of 52 and 10–30%, respectively, have been reported following endovascular treatment of intracranial aneurysms, raising clinical concerns regarding procedural efficacy. We compare residual, recurrence and re-treatment rates subject to different endovascular techniques in both ruptured and unruptured intracranial aneurysms at a comprehensive state-wide tertiary neurovascular centre in Australia. Methods Medical records, procedural and follow-up imaging studies of all patients who underwent endovascular treatment for intracranial aneurysms between July 2010 and July 2017 were reviewed retrospectively. Residuals, recurrences and re-treatment rates were assessed regarding initial aneurysm rupture status and applied endovascular technique: primary coiling, balloon- and stent-assisted coiling and flow diversion. Results Among 233 aneurysms, residual, recurrence and re-treatment rates were 27, 11.2 and 9.4%, respectively. Compared with unruptured aneurysms, similar residual and recurrence (p > .05), but higher re-treatment rates (4.5% vs. 19%; p < .001) were found for ruptured aneurysms. Residual, recurrence and re-treatment rates were: 13.3, 16 and 12% for primary coiling; 12, 12 and 10.7% for balloon-assisted coiling; 14.9, 7.5 and 4.5% for stent-assisted coiling; 91.9, 0 and 5.4% for flow diversion. Stent-assistance and flow-diversion were associated with lower recurrence and re-treatment rates, when compared with primary- and balloon-assisted coiling (p < .05). Conclusions Residuals and recurrences after endovascular treatment of intracranial aneurysms are less common than previously reported. Stent assistance and flow diversion seem associated with reduced recurrence- and re-treatment rates, when compared with primary- and balloon-assisted coiling. Restrained use of stents in ruptured aneurysms may be a contributing factor for higher recurrence/retreatment rates compared to unruptured aneurysms.


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