Posterior Communicating Artery Aneurysm Rupture Research Articles

Morphological evaluation of the risk of posterior communicating artery aneurysm rupture: a mirror aneurysm model.

The aim of this study was to use morphological parameters of mirror posterior communicating artery (PCoA) aneurysms to evaluate aneurysm rupture risk. The morphological parameters of 45 pairs of ruptured mirror PCoA aneurysms were analyzed. Conditional univariate and multivariate logistic regression of the following paired morphological parameters was performed: aneurysm with a daughter sac, aneurysm height, aneurysm width, neck width, internal carotid artery diameter, PCoA diameter, flow angle, PCoA angle, aspect ratio, bottleneck factor, size ratio, height/width ratio, fetal posterior cerebral artery, and aneurysm with height > width. A scoring system was established according to the odds ratios (ORs). The receiver operating characteristic was used to test the prediction accuracy of this scoring system in the authors' database of 523 PCoA aneurysms and the threshold value was used to define higher risk. Aneurysm width (OR 1.676, p = 0.014), aneurysm with daughter sac (OR 7.775, p = 0.016), and aneurysm with height > width (OR 9.067, p = 0.012) were independent risk factors for rupture. The scoring system consisted of aneurysm width (1 point per mm), aneurysm with a daughter sac (5 points), and aneurysm with height > width (5 points). The area under the curve (AUC) of the scoring system was 0.842, and its threshold value was 7.97. A score ≥ 8 points was defined as higher risk. The AUC using this definition was 0.802. Aneurysm width, aneurysms with height > width, and aneurysms with a daughter sac were independent risk factors for PCoA aneurysm rupture. The scoring system devised in this study accurately predicts rupture risk.

Infratentorial retroclival and tentorial subdural hematoma from posterior communicating artery aneurysm rupture: A case report and systematic review of literature.

The objective of this systematic review is to evaluate the pathogenesis, clinical course, and prognosis of patients who suffer from aneurysm rupture, leading to subdural hematoma (SDH) of the infratentorial space without associated subarachnoid hemorrhage (SAH). Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a literature review was conducted in PubMed and Scopus electronic databases for relevant published cases of aneurysmal SDH (AnSDH) of the infratentorial compartment without associated SAH. The presentation, treatment, clinical course, and outcome of identified cases are compiled. In addition, a patient suffering from an infratentorial SDH following aneurysm rupture is presented with an illustrative case. Three articles were identified and met inclusion criteria. All cases occurred from ruptured posterior communicating artery aneurysms. All patients arrived with a Hunt and Hess classification of 2 or less. Only one case was managed with operative aneurysm clipping and hematoma evacuation while the other three cases were managed endovascularly. There were no reported postoperative complications, vasospasm, or seizures reported. All patients had a final Modified Rankin score of 3 or less at last reported follow-up. Infratentorial AnSDH without associated SAH is an etiology rarely reported in the literature. Here, we present a case report and systematic review demonstrating a relatively benign clinical course and outcome compared to report aneurysm rupture associated with SAH or mixed SAH and SDH. Moreover, there appear to be lower rates of vasospasm and improved outcomes in patients with isolated AnSDH compared to the literature aneurysmal SAH rates.

Third Nerve Palsy Due to Posterior Communicating Artery Aneurysm Rupture Into the Subdural Space.

Third Nerve Palsy Due to Posterior Communicating Artery Aneurysm Rupture Into the Subdural Space.

Age and morphology of posterior communicating artery aneurysms

Risk of intracranial aneurysm rupture could be affected by geometric features of intracranial aneurysms and the surrounding vasculature in a location specific manner. Our goal is to investigate the morphological characteristics associated with ruptured posterior communicating artery (PCoA) aneurysms, as well as patient factors associated with the morphological parameters.Three-dimensional morphological parameters in 409 patients with 432 PCoA aneurysms diagnosed at the Brigham and Women’s Hospital and Massachusetts General Hospital between 1990 and 2016 who had available CT angiography (CTA) or digital subtraction angiography (DSA) were evaluated. Morphological parameters examined included aneurysm wall irregularity, presence of a daughter dome, presence of hypoplastic or aplastic A1 arteries and hypoplastic or fetal PCoA, perpendicular height, width, neck diameter, aspect and size ratio, height/width ratio, and diameters and angles of surrounding parent and daughter vessels. Univariable and multivariable statistical analyses were performed to determine the association of morphological parameters with rupture of PCoA aneurysms. Additional analyses were performed to determine the association of patient factors with the morphological parameters. Irregular, multilobed PCoA aneurysms with larger height/width ratios and larger flow angles were associated with ruptured PCoA aneurysms, whereas perpendicular height was inversely associated with rupture in a multivariable model. Older age was associated with lower aspect ratio, with a trend towards lower height/width ratio and smaller flow angle, features that are associated with a lower rupture risk. Morphological parameters are easy to assess and could help in risk stratification in patients with unruptured PCoA aneurysms. PCoA aneurysms diagnosed at older age have morphological features associated with lower risk.

Riskier-than-expected occlusive treatment of ruptured posterior communicating artery aneurysms: treatment and outcome of 620 consecutive patients.

Occlusive treatment of posterior communicating artery (PCoA) aneurysms has been seen as a fairly uncomplicated procedure. The objective here was to determine the radiological and clinical outcome of patients after PCoA aneurysm rupture and treatment and to evaluate the risk factors for impaired outcome. In a retrospective clinical follow-up study, data were collected from 620 consecutive patients who had been treated for ruptured PCoA aneurysms at a single center between 1980 and 2014. The follow-up was a minimum of 1 year after treatment or until death. Of the 620 patients, 83% were treated with microsurgical clipping, 8% with endovascular coiling, 2% with the two procedures combined, 1% with indirect surgical methods, and 6% with conservative methods. The most common procedural complications were treatment-related brain infarctions (15%). The occurrence of artery occlusions (10% microsurgical, 8% endovascular) was higher than expected. Most patients made a good recovery at 1 year after aneurysmal subarachnoid hemorrhage (modified Rankin Scale [mRS] score 0-2: 386 patients [62%]). A fairly small proportion of patients were left severely disabled (mRS score 4-5: 27 patients [4%]). Among all patients, 20% died during the 1st year. Independent risk factors for an unfavorable outcome, according to the multivariable analysis, were poor preoperative clinical condition, intracerebral or subdural hematoma due to aneurysm rupture, age over 65 years, artery occlusion on postoperative angiography, occlusive treatment-related ischemia, delayed cerebral vasospasm, and hydrocephalus requiring a shunt. Even though most patients made a good recovery after PCoA aneurysm rupture and treatment during the 1st year, the occlusive treatment-related complications were higher than expected and caused morbidity even among initially good-grade patients. Occlusive treatment of ruptured PCoA aneurysms seems to be a high-risk procedure, even in a high-volume neurovascular center.

Morphometry and hemodynamics of posterior communicating artery aneurysms: Ruptured versus unruptured

Posterior communicating artery (PCoA) aneurysms frequently rupture in small size (<7 mm). The aim of the study is to demonstrate morphometric and hemodynamic analyses in ruptured and unruptured PCoA aneurysms to improve predictive accuracy for rupture. Geometrical models were reconstructed from rotational DSA images of 57 ruptured and 22 unruptured side-wall PCoA aneurysms, which were classified into four two-dimensional (2D) groups by a combination of H/D and H/S ratios (H: dome height, D: dome diameter, and S: semi-axis height). Surface area ratio (SAR) of low time-averaged wall shear stress (TAWSS, ≤4 dynes cm−2) and high oscillatory shear index (OSI, ≥0.15) were computed in aneurysms. We hypothesized that a two-step analysis method, i.e., one-dimensionally morphometric and hemodynamic analyses in each 2D group, can enhance accuracy of PCoA aneurysm rupture evaluation. There was the highest incidence of H/D > 1 and H/S ≤ 2 with the largest surface area and SAR-TAWSS, but the lowest incidence of H/D ≤ 1 and H/S > 2 with the smallest surface area and SAR-TAWSS in ruptured PCoA aneurysms. PCoA aneurysms of H/D > 1 and H/S ≤ 2 with surface area > 70 mm2, H/D ≤ 1 and H/S > 2 with neck diameter > 2.3 mm, H/D ≤ 1 and H/S ≤ 2 with aneurysmal height/parent diameter ratio > 1.0, and H/D > 1 and H/S > 2 with aneurysmal angle > 115° need special attention for clinical diagnosis and treatment. The study highlighted the importance of the two-step analysis method for clinical evaluation of PCoA aneurysm rupture.

Angioarchitectures and Hemodynamic Characteristics of Posterior Communicating Artery Aneurysms and Their Association with Rupture Status.

Intracranial aneurysms originating at the posterior communicating artery are known to have high rupture risk compared with other locations. We tested the hypothesis that different angioarchitectures (ie, branch point configuration) of posterior communicating artery aneurysms are associated with aneurysm hemodynamics, which in turn predisposes aneurysms to rupture. A total of 313 posterior communicating artery aneurysms (145 ruptured, 168 unruptured) were studied with image-based computational fluid dynamics. Aneurysms were classified into different angioarchitecture types depending on the location of the aneurysm with respect to parent artery bifurcation. Hemodynamic characteristics were compared between ruptured and unruptured aneurysms, as well as among aneurysms with different angioarchitectures. Angioarchitecture was associated with rupture (P = .003). Ruptured aneurysms had higher, more concentrated, and more oscillatory wall shear stress distributions (maximum wall shear stress, P < .001; shear concentration index, P < .001; mean oscillatory shear index, P < .001), stronger and more concentrated inflow jets (represented as Q, P = .01; inflow concentration index, P < .001), and more complex and unstable flow patterns (vortex core length, P < .001; proper orthogonal decomposition entropy, P < .001) compared with unruptured aneurysms. These adverse conditions were more common in aneurysms with bifurcation-type angioarchitectures compared with those with lateral or sidewall angioarchitectures. Interestingly, ruptured aneurysms also had lower normalized mean wall shear stress (P = .02) and minimum wall shear stress (P = .002) than unruptured aneurysms. High-flow intrasaccular hemodynamic characteristics, commonly found in bifurcation-type angioarchitectures, are associated with the posterior communicating artery aneurysm rupture status. These characteristics include strong and concentrated inflow jets, concentrated regions of elevated wall shear stress, oscillatory wall shear stress, lower normalized wall shear stress, and complex and unstable flow patterns.

Carotid siphon morphology: Is it associated with posterior communicating aneurysms?

Posterior communicating artery (PComA) aneurysm seems to behave uniquely compared with other intracranial aneurysms at different locations. The association between the morphology of the carotid siphon and PComA aneurysms is not well known. This study aimed to investigate whether the anatomical characteristics of the carotid siphon are associated with the formation and rupture of PComA aneurysms. One hundred and thirty-two patients were retrospectively reviewed in a monocentric case-control study. Sixty-seven consecutive patients with PComA aneurysms were included in the case group, and 65 patients with anterior circulation aneurysm situated in other intracranial locations were included in the control group, matched by age and sex. Morphological characteristics of the carotid siphon were analyzed using angiography images. A univariate analysis was used to investigate the association between the morphological characteristics and the formation of PComA aneurysms. Furthermore, a subgroup analysis within the case group compared ruptured and non-ruptured PComA aneurysms. Patients with PComA aneurysm had a significantly (1.31 ± 0.70 vs. 0.82 ± 0.46; P < 0.001) larger PComA. No association was observed between the morphological characteristics of the carotid siphon and the presence of a PComA aneurysm. Likewise, subgroup analysis showed no significant association between morphological characteristics of the carotid siphon and aneurysm rupture. This case-control study shows that the carotid siphon morphology seems not to be related to PComA aneurysm formation or rupture.

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

Background and PurposeThe conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms.Materials and MethodsIn 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms.ResultsWhile univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001) and LSA (OR = 1.393, p = 0.041).ConclusionsHemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms.

Abstract TP91: Vessel Wall Imaging Demonstrates Aneurysm Wall Enhancement in Unruptured Posterior Communicating Artery Aneurysms With Oculomotor Nerve Palsy

Background: In ruptured aneurysms, vessel wall imaging (VWI) shows aneurysm wall enhancement, which may be caused by inflammation of the aneurysm wall. However, whether this inflammation is the cause or the result of aneurysm rupture remains unknown. In this study, we analyzed high-resolution VWI on posterior communicating artery (PComA) aneurysms, seeking to better understand aneurysm wall inflammation. Hypothesis: Oculomotor nerve palsy (ONP) is a warning sign of PComA aneurysm rupture. ONP results from compression of the oculomotor nerve and indicates aneurysm enlargement. Thus, PComA aneurysms with ONP are about to rupture, which makes them perfect cases to research aneurysm wall inflammation. If the inflammation of the aneurysm wall is the cause of aneurysm rupture, VWI may capture images of aneurysm wall enhancement before it ruptures. Methods: PComA aneurysm patients with ONP were examined using a Verio 3.0T scanner with a 12-channel head coil (Siemens Healthcare, Erlangen, Germany). Time-of-flight MRI angiography was performed to localize the aneurysm site. Then, a high-resolution T1-weighted black blood vessel wall sequence was obtained before and after intravenous administration of gadolinium. Each sequence was performed in the axial planes. Additional coronal planes or other planes were obtained if necessary. Patients with ruptured PComA aneurysms were also examined as a positive control, and patients with unruptured PComA aneurysms without ONP were examined as a negative control. Results: Ten patients with PComA aneurysm were examined. VWI of 3 patients with ONP showed aneurysm wall enhancement. Of these 3 patients, 2 were with post-orbital pain, and VWI showed complete enhancement of the aneurysm wall. VWI showed partial enhancement of the aneurysm wall in the other one patient without post-orbital pain. In the positive control group, complete wall enhancement was seen in all 3 ruptured PComA aneurysms (2 with ONP, 1 without ONP). In the negative control group of 4 cases, no aneurysm wall enhancement was seen. Conclusion: VWI demonstrated aneurysm wall enhancement in PComA aneurysms with ONP, which indicates that wall inflammation may occur before aneurysm rupture.

Clinical, morphological, and hemodynamic independent characteristic factors for rupture of posterior communicating artery aneurysms

ObjectiveTo identify clinical, morphological, and hemodynamic independent characteristic factors that discriminate posterior communicating artery (PCoA) aneurysm rupture status.Methods173 patients with single PCoA aneurysms (108 ruptured, 65 unruptured) between January 2012...

Analyses of risk factors for posterior communicating artery aneurysm rupture

Objective To analyze the risk factors for posterior communicating artery (PCoA) aneurysm rupture from the clinical and morphological aspects. Methods Consecutive patients with single PCoA aneurysm admitted to hospital from January 2011 to December 2013 were analyzed retrospectively. The clinical data and imaging characteristics were analyzed with univariate analysis and multivariate logistic regression analysis. Results Univariate analysis indicated that there were significant differences in the rupture rate of PCoA aneurysms in the history of hypertension (χ2=23.013, P=0.000) , aspect ratio (AR) ≥1.5 (χ2=8.492, P=0.004), directions of different aneurysm tops (χ2=15.057, P=0.002), and aneurysm blebs (χ2=18.952, P=0.000) between the two groups. The results of multivariate logistic regression analysis were the history of hypertension (OR, 13.240, P=0.000), presence of aneurysm blebs (OR, 12.933, P=0.001), age less than 60 years (OR, 3.766, P=0.010), AR ≥1.5 (OR=4.997, P=0.001), and posterior-inferior-lateral directions of aneurysm tops (OR, 7.584, P=0.038). Conclusion The history of hypertension, presence of aneurysm blebs, age less than 60 years, AR ≥1.5 and posterior-inferior-lateral directions of aneurysm tops were the risk factors for PCoA aneurysm rupture. Key words: Intracranial aneurysm; Risk factors; Posterior communicating artery

Morphology Parameters for Mirror Posterior Communicating Artery Aneurysm Rupture Risk Assessment.

Recent studies have shown that posterior communicating artery (PComA) aneurysms are more likely to rupture. However, surgical intervention for PComA aneurysms may be associated with increased treatment-related morbidity rate. Therefore, it is meaningful to investigate the factors related to PComA aneurysm rupture. The purpose of this study was to identify morphological parameters that significantly correlate with PComA aneurysm rupture. We divided 14 pairs of mirror posterior communicating artery aneurysms (PComA-MANs) into ruptured and unruptured groups. Computed tomography angiography (CTA) imaging was evaluated with three-dimensional (3D) Slicer to generate models of the aneurysms and surrounding vasculature. Nine morphological parameters [size, height, width, neck width, aspect ratio (AR), bottleneck factor (BNF), height/width ratio (H/W), size ratio (SR), and bleb formation] were examined in the two groups for significance with respect to rupture. By contrast, statistically significant differences were found in ruptured and unruptured group for size, AR, BNF, SR, and bleb formation (P < 0.05). Parameters that had no significant differences between the two groups were height (P = 0.103), width (P = 0.078), neck width (P = 0.808), and H/W (P = 0.417). We conclude that MANs may be a useful model for the morphological analysis of intracranial aneurysm rupture. Larger size, higher AR, BNF, SR, and bleb formation may be related to rupture of PComA aneurysms. Larger sample studies minimizing the interference from patient-related factors and aneurysm type were expected for acquiring more accurate assessment of the relationship between these parameters and PComA aneurysm rupture.

Morphological parameters associated with ruptured posterior communicating aneurysms.

The rupture risk of unruptured intracranial aneurysms is known to be dependent on the size of the aneurysm. However, the association of morphological characteristics with ruptured aneurysms has not been established in a systematic and location specific manner for the most common aneurysm locations. We evaluated posterior communicating artery (PCoA) aneurysms for morphological parameters associated with aneurysm rupture in that location. CT angiograms were evaluated to generate 3-D models of the aneurysms and surrounding vasculature. Univariate and multivariate analyses were performed to evaluate morphological parameters including aneurysm volume, aspect ratio, size ratio, distance to ICA bifurcation, aneurysm angle, vessel angles, flow angles, and vessel-to-vessel angles. From 2005–2012, 148 PCoA aneurysms were treated in a single institution. Preoperative CTAs from 63 patients (40 ruptured, 23 unruptured) were available and analyzed. Multivariate logistic regression revealed that smaller volume (p = 0.011), larger aneurysm neck diameter (0.048), and shorter ICA bifurcation to aneurysm distance (p = 0.005) were the most strongly associated with aneurysm rupture after adjusting for all other clinical and morphological variables. Multivariate subgroup analysis for patients with visualized PCoA demonstrated that larger neck diameter (p = 0.018) and shorter ICA bifurcation to aneurysm distance (p = 0.011) were significantly associated with rupture. Intracerebral hemorrhage was associated with smaller volume, larger maximum height, and smaller aneurysm angle, in addition to lateral projection, male sex, and lack of hypertension. We found that shorter ICA bifurcation to aneurysm distance is significantly associated with PCoA aneurysm rupture. This is a new physically intuitive parameter that can be measured easily and therefore be readily applied in clinical practice to aid in the evaluation of patients with PCoA aneurysms.

Morphological and clinical risk factors for posterior communicating artery aneurysm rupture

Recent studies have shown that posterior circulation aneurysms, specifically posterior communicating artery (PCoA) aneurysms, are more likely to rupture than other aneurysms. To date, few studies have investigated the factors contributing to PCoA aneurysm rupture. The authors aimed to identify morphological and clinical characteristics predisposing to PCoA aneurysm rupture. The authors retrospectively reviewed 134 consecutive patients with PCoA aneurysms managed at their facility between July 2003 and December 2012. The authors divided patients into groups of those with aneurysmal rupture (n = 39) and without aneurysmal rupture (n = 95) and compared morphological and clinical characteristics. Morphological characteristics were mainly evaluated by 3D CT angiography and included diameter of arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery), size of the aneurysm, dome-to-neck ratio, neck direction of the aneurysmal dome around the PCoA (medial, lateral, superior, inferior, and posterior), aneurysm bleb formation, whether the PCoA was fetal type, and the existence of other intracranial unruptured aneurysm(s). Patients with ruptured PCoA aneurysms were significantly younger (a higher proportion were < 60 years of age) and a significantly higher proportion of patients with ruptured PCoA aneurysms showed a lateral direction of the aneurysmal dome around the PCoA, had bleb formation, and the aneurysm was > 7 mm in diameter and/or the dome-to-neck ratio was > 2.0. Multivariate logistic regression analysis showed age < 60 years (OR 4.3, p = 0.011), history of hypertension (OR 5.1, p = 0.008), lateral direction of the aneurysmal dome around the PCoA (OR 6.7, p = 0.0001), and bleb formation (OR 11, p < 0.0001) to be significantly associated with PCoA aneurysm rupture. The present results demonstrated that lateral projection of a PCoA aneurysm may be related to rupture.

Two cases of ruptured cerebral aneurysms presenting with contralateral hematomas

We present two cases of hematoma contralateral to the aneurysm. Case 1 is a 62-year-old woman presenting with a large left frontal intraparenchymal hematoma (IPH) and a right posterior communicating artery (PCoA) aneurysm. This is the first reported case of a contralateral frontal IPH from PCoA aneurysm rupture. Case 2 is a 58-year-old male with right PCoA aneurysm and left sylvian SAH. Both patients underwent coil embolization of offending lesions, with repeat angiograms revealing no other vascular anomalies.