PcomA Aneurysms Research Articles

Rare simultaneous fetal posterior cerebral artery and conventional posterior cerebral artery duplication in a patient with a ruptured posterior communicating artery aneurysm: illustrative case.

The fetal-type posterior cerebral artery (PCA) is defined as a variant anatomy in which the posterior communicating artery (PCOM) is larger than the hypoplastic or aplastic P1 segment of the PCA. The authors present the novel case of a patient with a duplicated right PCA in parallel with fetal-type and conventional PCAs supplying adjacent components of the PCA cerebral territory. A 59-year-old woman presented with a modified Fisher Scale score 4 subarachnoid hemorrhage. A right irregular PCOM aneurysm that measured 9.5 mm × 4.5 mm × 4.5 mm arose from the base of a variant branch supplying a portion of the PCA, rather than a conventional PCOM, and was found on digital subtraction angiography. Following endovascular coil embolization, the patient was discharged home. The fetal-type variant has implications for thromboembolic events. If an embolism occludes the anterior circulation in a patient with a fetal-type PCA, it may result in an infarct in the PCA territory. Awareness of cerebral arterial anatomy, including an atypical collateral supply, informs a treating team's latitude in tolerance of which sites must be preserved and which can be safely sacrificed. https://thejns.org/doi/10.3171/CASE23735.

Neurosurgical management of posterior communicating artery aneurysmal perforators

Background: Posterior communicating artery (PCom) aneurysms are prevalent intracranial aneurysms, frequently leading to subarachnoid haemorrhage and third nerve palsy. "True" perforators originating directly from the PCom aneurysmal sac are rare and pose unique surgical challenges. We present two illustrative cases where "true" PCom perforators were identified during surgery, necessitating tailored microsurgical approaches. Case Reports: In case one, a 35-year-old female presented with a large PCom aneurysm. During surgery, a modified clipping technique successfully preserved a perforator originating from the aneurysmal sac. In case two, a 36-year-old male with a PCom aneurysm was found to have a perforator supplying the mesial temporal cortex. Sacrificing this perforator was necessary for aneurysm clipping. Conclusion: This paper underscores the rarity of "true" PCom perforators and their impact on microsurgical approaches. Preoperative imaging techniques often fail to detect these small-calibre vessels, highlighting the importance of intraoperative identification. Tailored approaches based on individual anatomy and clinical context are essential. While endovascular procedures provide alternatives, adaptability in microsurgical techniques remains crucial for cases requiring intraoperative perforator management. Overall, understanding the complex vascular intricacies of PCom aneurysms, including "true" perforators, is vital for neurosurgeons. The delicate balance between preservation and necessity, along with ongoing research for improved preoperative identification, stands as the cornerstone for enhancing surgical outcomes in these complex cases.

It Is Necessary to Pay Attention to Where the Pcom Originate from the Aneurysm to Treat with FD.

Objective With the expansion of indications of flow diverter (FD) for cerebral aneurysms, FD placement for posterior communicating artery (Pcom) aneurysms has been approved. However, it is controversial whether Pcom aneurysms should be treated with FD or not. In this study, we report the outcome of FD treatment for Pcom aneurysms in Japan. Materials and Methods We retrospectively analyzed 36 patients with 38 aneurysms treated with FD placement for Pcom aneurysms between 2015 and 2021 in our hospital. We divided our cases into complete occlusion (CO) and non-CO groups. And we extracted contributing factors to CO using multivariate analysis. We also compared the complications rate among the three types of FDs. Results CO was obtained in 29 cases (79.3%), and complications were observed in 3 cases (7.9%). Multivariate analysis revealed that the type of Pcom branch from the aneurysmal dome was a significant factor contributing to CO (odds ratio: 0.0052, 95% confidence interval 0.000048-0.584, p = 0.029). In terms of complications, complication rate was significantly higher in the Flow-Redirection Endoluminal Device (FRED) group ( p = 0.0491). Conclusion The outcome for Pcom aneurysms treated by FD was acceptable. When treating, we must pay attention to where Pcom originates. Achieving CO with FD is difficult for aneurysms where the Pcom branches from the dome. Furthermore, when treating Pcom aneurysms with FRED, it is necessary to be careful about thromboembolic complications.

Recovery of Oculomotor Nerve Palsy After Surgical and Endovascular Repair of Unruptured Internal Carotid-Posterior Communicating Artery Aneurysms

Unruptured posterior communicating artery (Pcom) aneurysms cause oculomotor nerve palsy (ONP). However, the time course of recovery after aneurysm repair remains unclear. We aimed to evaluate the ONP course after clipping and coiling for unruptured Pcom aneurysms. We retrospectively reviewed the medical records of 25 consecutive patients with ONP due to unruptured Pcom aneurysms, undergoing aneurysm repair at our institution during 2010-2022. We analyzed the clinical data, angiographic results, and surgical complications. The time to ONP recovery was evaluated using the Kaplan-Meier method. This study included 14 patients undergoing surgical clipping and 11 undergoing endovascular coiling. The two groups exhibited no significant differences in complete or partial ONP percentage or in symptom presentation (ptosis, diplopia, ocular paralysis, pupillary light reflex disorder, or mydriasis). All patients achieved complete or partial recovery during the follow-up period. The median time to partial or complete improvement in ONP was significantly shorter for clipping compared to coiling (2days vs. 33days; P= 0.009). Preoperative partial and complete ONP were stratified; clipping improved significantly earlier than coiling in the complete ONP group (P= 0.010). In the early treatment group (based on the median duration of treatment), clipping resulted in earlier improvement than coiling (P= 0.014). In the small aneurysm group (based on the median of the aneurysm maximum diameter), clipping resulted in earlier improvement than coiling (P= 0.005). In ONP caused by an unruptured Pcom aneurysm, clipping may provide faster recovery than coiling, particularly in cases of early onset, complete palsy, and small aneurysms.

Geometry and Symmetry of Willis' Circle and Middle Cerebral Artery Aneurysms Development.

Background: A relationship between the geometry and symmetry of Willis' circle and intracranial aneurysms was reported for anterior communicating and posterior communicating (PCom) aneurysms. A similar association with the middle cerebral artery (MCA) aneurysms instead appeared weaker. Methods: We reviewed 432 patients from six Italian centers with unilateral MCA aneurysms, analyzing the relationship between the caliber and symmetry of Willis' circle and the presence of ruptured and unruptured presentation. CT-angiograms were evaluated to assess Willis' circle geometrical characteristics and the MCA aneurysm side, dimension and rupture status. Results: The hypoplasia of the first segment of the anterior cerebral artery (A1) was in approximately one-quarter of patients and PCom hypoplasia was in almost 40%. About 9% had a fetal PCom ipsilaterally to the aneurysm. By comparing the aneurysmal and healthy sides, only the PCom hypoplasia appeared significantly higher in the affected side. Finally, the caliber of the internal carotid artery (ICA) and the first segment of MCA (M1) caliber were significantly greater in patients with unruptured aneurysms, and PCom hypoplasia appeared related to the incidence of an ipsilateral MCA aneurysm and its risk of rupture. Conclusions: Although according to these findings asymmetries of Willis' circle are shown to be a risk factor for MCA aneurysm formation and rupture, the indifferent association with ipsilateral or contralateral hypoplasia remains a datum of difficult hemodynamic interpretation, thereby raising the concern that this association may be more casual than causal.

Factors affecting resolution of oculomotor nerve palsy following endovascular embolization of posterior communicating artery aneurysms

PurposeTo investigate the effect of endovascular embolization of posterior communicating artery (Pcom) aneurysms on concomitant oculomotor nerve palsy (OMNP) and factors affecting the effect of treatment. Materials and methodsPatients with the Pcom aneurysms concomitant with OMNP were retrospectively enrolled for endovascular treatment of the aneurysms. All patients had the endovascular management. The clinical effect, degree of OMNP, size of the aneurysm, type of treatment, subarachnoid hemorrhage (SAH), and time from onset to treatment were analyzed on the resolution of OMNP. ResultsNinety-six patients with 99 Pcom aneurysms were enrolled and treated endovascularly, with the success rate of 100%. Immediately after endovascular treatment, 75 aneurysms (75.75%) got complete occlusion, and 24 (24.24%) nearly complete occlusion. Followed up for 3–18 (mean 8.52±0.56) months, complete resolution of the OMNP was achieved in 63 patients (65.63%), partial resolution in 21 (21.88%), and non-recovery in the other 12 (12.50%). The degree of OMNP at onset, SAH, and time from onset to treatment were significantly (P<0.05) correlated with the resolution of OMNP. Univariate analysis revealed that younger age of the patient, degree of OMNP at onset, presence of subarachnoid hemorrhage, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. Multivariate analysis revealed that the younger age, degree of OMNP at onset, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. ConclusionEndovascular embolization of Pcom aneurysms concomitant with OMNP can effectively improve the OMNP symptoms, especially for patients with moderate and a shorter history of OMNP. Younger age, degree of oculomotor nerve palsy at onset, and time from onset to treatment may significantly affect recovery of oculomotor nerve palsy.

How does the recurrence-related morphology characteristics of the Pcom aneurysms correlated with hemodynamics?

Posterior communicating artery (Pcom) aneurysm has unique morphological characteristics and a high recurrence risk after coil embolization. This study aimed to evaluate the relationship between the recurrence-related morphology characteristics and hemodynamics. A total of 20 patients with 22 Pcom aneurysms from 2019 to 2022 were retrospectively enrolled. The recurrence-related morphology parameters were measured. The hemodynamic parameters were simulated based on finite element analysis and computational fluid dynamics. The hemodynamic differences before and after treatment caused by different morphological features and the correlation between these parameters were analyzed. Significant greater postoperative inflow rate at the neck (Qinflow), relative Qinflow, inflow concentration index (ICI), and residual flow volume (RFV) were reported in the aneurysms with wide neck (>4 mm). Significant greater postoperative RFV were reported in the aneurysms with large size (>7 mm). Significant greater postoperative Qinflow, relative Qinflow, and ICI were reported in the aneurysms located on the larteral side of the curve. The bending angle of the internal carotid artery at the initiation of Pcom (αICA@PCOM) and neck diameter had moderate positive correlations with Qinflow, relative Qinflow, ICI, and RFV. The morphological factors, including aneurysm size, neck diameter, and αICA@PCOM, are correlated with the recurrence-inducing hemodynamic characteristics even after fully packing. This provides a theoretical basis for evaluating the risk of aneurysm recurrence and a reference for selecting a surgical plan.

Sellar hematoma as a new potential radiological clue for superior hypophyseal artery aneurysm rupture

Background. In cases of spontaneous subarachnoid haemorrhage (SAH) with multiple intracranial aneurysms (MIAs) detected on angiography, some radiological clues assist in determining the site of a ruptured aneurysm which is bleeding is quite beneficial for the selection of the best treatment strategy. Case description. We report a case of a 60 years old patient who presented with spontaneous SAH, sellar hematoma, and three different aneurysms detected in angiography. Although the right Posterior communicating artery (PcomA) aneurysms showed Murphy’s teat on angiography intraoperatively, we discovered that the right superior hypophyseal aneurysm (SHA) was the source of the index bleeding. Both aneurysms were clipped successfully. Conclusion. From the preoperative radiological and intraoperative surgical findings, we propose that sellar hematoma on a non-contrast CT scan is a new potential sign to be correlated with superior hypophyseal artery aneurysm rupture.

Impact of Morphological Factors on the Future Growth of Unruptured Posterior Communicating Artery Aneurysms

No previous study has established the factors associated with intracranial aneurysm growth using imaging data obtained before the appearance of morphological changes. Therefore, we investigated the factors related to future aneurysm growth in posterior communicating artery (Pcom) aneurysms. Using a longitudinal database of intracranial aneurysm cases, we reviewed the findings for consecutive patients with unruptured Pcom aneurysms admitted to our institute from 2012 to 2021. Magnetic resonance images obtained over time were used to evaluate aneurysm growth. Aneurysms showing growth over time (group G) and unchanged aneurysms (group U) were compared in terms of background data and morphological factors. 93 Pcom aneurysms (group G: 25 aneurysms, 25%; group U: 68 aneurysms, 75%) were eligible for the present study. Six aneurysm rupture events occurred in group G (24%). Among morphological factors, Pcom diameter (1.2±0.3mm vs. 0.8±0.7mm, P<0.01), bleb formation (group G: 39% vs. group U: 10%; odds ratio, 5.6; P=0.01), and the lateral projection of the dome (group G: 52% vs. group U: 13%; odds ratio, 3.2; P=0.023) were significantly different between the 2 groups. The sensitivity and specificity of a cutoff Pcom diameter of 0.73mm for predicting enlargement were 96% and 53%, respectively. Pcom diameter, bleb formation, and lateral dome projection were associated with growth of Pcom aneurysms. Aneurysms with these risk factors require careful follow-up imaging, which may facilitate early detection of aneurysm growth and prevention of rupture through therapeutic interventions.

Sex-related differences in symptom presentation of patients with aneurysmal subarachnoid hemorrhage.

Background: In patients with myocardial infarction, atypical symptoms at onset have been demonstrated in women. We aimed to investigate the presence of sex-related differences in symptom presentation in patients with aneurysmal subarachnoid hemorrhage (aSAH) to enable earlier diagnosis and treatment. Methods: We assessed symptoms on admission to hospital in 343 patients with aSAH in this retrospective single-center cohort-study. Univariate statistical analysis was performed by comparing sexes including the whole study population and subgroups (dichotomized using Fisher scale 1-2 vs. 3-4, WFNS grade 1-3 vs. 4-5, and anterior vs. posterior circulation aneurysms, respectively). Results: The majority of patients was female (63.6%, n=218, vs. 36.4%, n=125), the mean age 57.4 years (standard deviation (SD) 13.3) with older women compared to men (59.2, SD 13.8, vs. 54.4, SD 11.6; p=0.003). Anterior communicating artery (AcomA) aneurysms were most common (30.9%, n=106), predominantly in men (43.2%, n=54, vs. 23.9%, n=52; p=0.0002), whereas posterior communicating artery (PcomA) aneurysms were more frequent in women (19.3%, n=42, vs. 8.8%, n=11; p=0.005). Exercise-induced headache was more often reported by men (10.4%, n=13, vs. 5%, n=11; p=0.04) in all patients as well as in the subgroup of WFNS 1-3. Anisocoria was more frequent in women within the subgroup of severely impaired consciousness (WFNS 4-5; 25.3%, n=22, vs. 10.7%, n=6; p=0.032). For all other symptoms, there was no evidence for sex-specific differences in the whole study group as well as in subgroups. Conclusion: Our results show no evidence for relevant sex-related differences in symptom presentation at onset in aSAH patients. Women presenting with an acute onset anisocoria should be screened even more carefully for an underlying ruptured Pcom aneurysm.

Abstract Number ‐ 142: Flow Diversion for Posterior Communicating Artery Aneurysms: Systematic Review and Meta‐Analysis

Introduction Posterior communicating artery (PComA) aneurysms are common and have a high risk of rupture. Flow diverters (FD) have demonstrated a safe and effective profile. However, the use of FD in PComA aneurysms has shown controversial results with high rates of recurrence and a high risk of potential ischemic complications. There, we aimed to evaluate the safety and efficacy of flow diversion for the treatment of PComA aneurysms with a meta‐analysis of the literature. Methods We performed a systematic search in Scopus, Embase, Medline, and Web of Science from inception until May 2022 for all the studies that reported the safety and effectiveness of FD for the treatment of intracranial aneurysms located in the posterior communicating artery. The primary effectiveness endpoint was a complete aneurysm occlusion rate at final follow‐up. The primary safety endpoint was a composite measure of cumulative events that occurred during and after the procedure. Events included death and ischemic/hemorrhagic complications. Random‐effects meta‐analysis was used to calculate proportions. Statistical heterogeneity across studies was assessed with I2 statistics. Results A total of 13 studies with 397 patients harboring 403 aneurysms were included in our analysis. Mean age was 48 years and mean aneurysm size was 5.3 mm. Complete aneurysm occlusion at final follow‐up was 74% (95% CI 66–81%; I2 = 54%). The primary safety composite outcome was 5% (95% CI 3–9%; I2 = 0%). The mortality rate was 1% (95% CI 0–2%; I2 = 0%). Subgroup analysis showed that patients with a non‐fetal PComA had a higher rate (76%; 95% CI 62%‐86%; I2 = 53%) of complete aneurysm occlusion compared to those with a fetal PComA (36%; 95% CI 21%‐54%; I2 = 0%). Conclusions Our findings show that flow diversion for the treatment of aneurysms located in the PComA is effective and safe. However, the same treatment for aneurysms located in a fetal‐type PComA did not show the same efficacy profile suggesting that these cases might require an alternative treatment to achieve permanent occlusion rates.

Endovascular treatment of challenging aneurysms with FRED Jr flow diverter stents: a single-center experience.

To analyze clinical safety and efficacy of flow re-direction endoluminal device (FRED) Jr flow diverter for treatment of unruptured, ruptured, or recanalyzed aneurysms. Between October 2019 and February 2022, 25 patients with 31 aneurysms treated with FRED Jr were included in the study. Clinical and radiological records, procedural details, and follow-up outcomes were retrospectively evaluated. Eighteen (72%) patients were female. Median age was 48.8 (age range 9-85). Mean follow-up was 21months (6-28months). Location of the aneurysms were as follows; 13 in middle cerebral artery (MCA), 7 in anterior cerebral artery (ACA), 4 in posterior cerebral artery (PCA), 3 in true posterior communicating artery (PCom), 2 in anterior communicating artery (ACom), 1 in superior cerebellar artery (SCA), 1 in true ophthalmic artery. Five patients (20%) presented with acute subarachnoid hemorrhage (aSAH). In all procedures, FRED Jr was successfully deployed. Three true Pcom aneurysms and a true ophthalmic aneurysm were treated with FRED Jr. Three patients with two adjacent aneurysms were treated with a single FRED Jr. In two (8%) patients in-stent thrombosis occurred intraoperatively, they were treated with iv tirofiban and thrombectomy without any sequelae. Post-discharge 2weeks later, intraparenchymal hemorrhage occurred in a patient. He was treated with surgical drainage, the clinical course was modified Rankin score (mRS) 2. Digital subtraction angiography (DSA) was performed on 16 (64%) patients with 21 (67%) aneurysms. Near complete-complete occlusion (O'Kelly-Morata grading scale (OKM C-D) was documented in 15/16 (93.7%) patients, 20/21 (95.2%) aneurysms. In nine (36%) patients, no residual filling was observed in the magnetic resonance angiography (MRA). Good clinical outcome (mRS 0-1) was achieved in 24/25 (96%) of patients. Endovascular treatment of small cerebral aneurysms with FRED Jr is safe and effective even in complex and challenging morphologies allowing high rates of aneurysm occlusion with low periprocedural complications. Our cohort, consisting of a rate 20% acute ruptured aneurysms, is the major additive data to the published literature.

Effects of endovascular treatment and prognostic factors for recovery of oculomotor nerve palsy caused by posterior communicating artery aneurysms: a multi-center retrospective analysis

BackgroundOculomotor nerve palsy (ONP) may result from posterior communicating artery (PcomA) aneurysms. We aimed to evaluate the resolution of ONP after endovascular treatment with the intention of clarifying predictors of nerve recovery in a relatively large series.MethodsA total of 211 patients with ONP caused by PcomA aneurysms underwent endovascular coiling between May 2010 and December 2020 in four tertiary hospitals. We evaluated the demographics, clinical characteristics, aneurysm morphology parameters and ONP resolution to analyze the predictors of ONP recovery using univariate and multivariate analyses.ResultsAt the last available clinical follow-up, ONP resolution was complete in 126 (59.7%) patients, partial in 73 (34.6%) patients, and no recovery in 12 (5.7%) patients. The median resolution time after endovascular treatment was 55 days (interquartile range: 40–90 days). In multivariate analysis, degree of ONP (incomplete palsy) on admission (OR 5.396; 95% CI 2.836–10.266; P < 0.001), duration of ONP (≤ 14 days) before treatment (OR 5.940; 95% CI 2.724–12.954; P < 0.001) were statistically significant predictors of complete recovery of ONP. In the subgroup analysis of patients with unruptured aneurysms, aspirin showed a higher complete recovery rate in univariate analysis (OR 2.652; 95% CI 1.057–6.656; P = 0.038).ConclusionInitial incomplete ONP and early management might predict better recovery of ONP after endovascular treatment.

Sex-related differences in symptom presentation of patients with aneurysmal subarachnoid hemorrhage

Background: In patients with myocardial infarction, atypical symptoms at onset have been demonstrated in women. We aimed to investigate the presence of sex-related differences in symptom presentation in patients with aneurysmal subarachnoid hemorrhage (aSAH) to enable earlier diagnosis and treatment. Methods: We assessed symptoms on admission to hospital in 343 patients with aSAH in this retrospective single-center cohort-study. Univariate statistical analysis was performed by comparing sexes including the whole study population and subgroups (dichotomized using Fisher scale 1-2 vs. 3-4, WFNS grade 1-3 vs. 4-5, and anterior vs. posterior circulation aneurysms, respectively). Results: The majority of patients was female (63.6%, n=218, vs. 36.4%, n=125), the mean age 57.4 years (standard deviation (SD) 13.3) with older women compared to men (59.2, SD 13.8, vs. 54.4, SD 11.6; p=0.003). Anterior communicating artery (AcomA) aneurysms were most common (30.9%, n=106), predominantly in men (43.2%, n=54, vs. 23.9%, n=52; p=0.0002), whereas posterior communicating artery (PcomA) aneurysms were more frequent in women (19.3%, n=42, vs. 8.8%, n=11; p=0.005). Exercise-induced headache was more often reported by men (10.4%, n=13, vs. 5%, n=11; p=0.04) in all patients as well as in the subgroup of WFNS 1-3. Anisocoria was more frequent in women within the subgroup of severely impaired consciousness (WFNS 4-5; 25.3%, n=22, vs. 10.7%, n=6; p=0.032). For all other symptoms, there was no evidence for sex-specific differences in the whole study group as well as in subgroups. Conclusion: Our results show no evidence for relevant sex-related differences in symptom presentation at onset in aSAH patients. Women presenting with an acute onset anisocoria should be screened even more carefully for an underlying ruptured Pcom aneurysm.

A web-based dynamic nomogram for rupture risk of posterior communicating artery aneurysms utilizing clinical, morphological, and hemodynamic characteristics.

BackgroundPredicting rupture risk is important for aneurysm management. This research aimed to develop and validate a nomogram model to forecast the rupture risk of posterior communicating artery (PcomA) aneurysms.MethodsClinical, morphological, and hemodynamic parameters of 107 unruptured PcomA aneurysms and 225 ruptured PcomA aneurysms were retrospectively analyzed. The least absolute shrinkage and selection operator (LASSO) analysis was applied to identify the optimal rupture risk factors, and a web-based dynamic nomogram was developed accordingly. The nomogram model was internally validated and externally validated independently. The receiver operating characteristic (ROC) curve was used to assess the discrimination of nomogram, and simultaneously the Hosmer–Lemeshow test and calibration plots were used to assess the calibration. Decision curve analysis (DCA) and clinical impact curve (CIC) were used to evaluate the clinical utility of nomogram additionally.ResultsFour optimal rupture predictors of PcomA aneurysms were selected by LASSO and identified by multivariate logistic analysis, including hypertension, aspect ratio (AR), oscillatory shear index (OSI), and wall shear stress (WSS). A web-based dynamic nomogram was then developed. The area under the curve (AUC) in the training and external validation cohorts was 0.872 and 0.867, respectively. The Hosmer–Lemeshow p > 0.05 and calibration curves showed an appropriate fit. The results of DCA and CIC indicated that the net benefit rate of the nomogram model is higher than other models.ConclusionHypertension, high AR, high OSI, and low WSS were the most relevant risk factors for rupture of PcomA aneurysms. A web-based dynamic nomogram thus established demonstrated adequate discrimination and calibration after internal and external validation. We hope that this tool will provide guidance for the management of PcomA aneurysms.

CTA Study of Ruptured Aneurysms of the Posterior Communicating Artery.

Background Only a few reported studies have used computed tomography angiography (CTA) to image ruptured aneurysms at the junction of the internal carotid artery (ICA) and posterior communicating artery (PcomA) in the context of the adjacent arteries. Therefore, we performed such a study using a GE Workstation. Methods The parameters of each aneurysm and its adjacent arteries were measured. Then, statistical assessments were performed to compare the parameters of the aneurysm side and the lesion-free (control) side. Results Sixty-three patients were included in this study. The average age was 62.1 ± 11.0 years, and the ratio of males to females was 0.8 : 1. The measurement results showed that the mean aneurysmal height was 5.2 ± 2.3 mm, the mean width was 4.7 ± 2.2 mm, and the mean neck width was 4.5 ± 1.9 mm. On the aneurysm side, the intradural ICA diameter was 4.34 ± 0.90 mm, and the diameter of the ICA at its termination was 3.55 ± 0.72 mm. A fetal-type PcomA was found in 52.4% of aneurysms. The other measured parameters were also provided. Statistical results showed that the height of the aneurysm was larger than the width (P < 0.05). The intradural ICA diameter, the ICA diameter at termination, the intradural ICA length, and the angle between the ICA and PcomA were larger in the aneurysm group than in the control group (P < 0.05). Conclusions This CTA study showed that the ruptured PcomA aneurysm was often wide-necked, nonspherical, and approximately 5 mm in size. In the presence of a ruptured PcomA aneurysm, the affected intradural ICA became thicker and longer than the contralateral control ICA, and the aneurysm significantly reduced the angle between the ICA and the PcomA.

Wall enhancement in unruptured posterior communicating aneurysms with oculomotor nerve palsy on magnetic resonance vessel wall imaging.

Recent MR vessel wall imaging studies of unruptured intracranial aneurysms (UIAs) have revealed that aneurysm wall enhancement (AWE) can be an indicator for aneurysm evolution; however, the degree of AWE among different types of evolving UIAs has yet to be clarified. The authors assessed the degree of AWE in unruptured posterior communicating artery (PcomA) aneurysms with oculomotor nerve palsy (ONP), which may be a subgroup of evolving UIAs with rapid enlargement and high rupture risk. The degree of AWE was analyzed in 35 consecutive evolving PcomA aneurysms (19 with and 16 without ONP). UIAs were considered to be evolving when showing growth or ONP. A 3D T1-weighted fast spin echo sequence was obtained after contrast media injection, and the contrast ratio of the aneurysm wall against the pituitary stalk (CRstalk) was calculated as the indicator of AWE. The CRstalk in evolving UIAs with ONP was compared with that in UIAs without ONP. The CRstalk was significantly higher in evolving UIAs with ONP than in those without ONP (0.85 vs 0.57; p = 0.006). In multivariable analysis, the CRstalk remained a significant indicator for ONP presentation in evolving UIAs (OR 6.13, 95% CI 1.21-31.06). AWE was stronger in evolving PcomA aneurysms with ONP than in those without ONP, suggesting the potential utility of AWE for risk stratification in evolving UIAs. The degree of AWE can be a promising indicator of a rupture-prone UIA, which can be useful information for the decision-making process in the treatment of UIAs.

Double-Balloon-Assisted Coiling for Wide-Necked Posterior Communicating Artery Aneurysms with a Fetal-Type Variant of the Posterior Cerebral Artery: A Case Series.

Endovascular treatment for wide-necked posterior communicating artery (PcomA) aneurysms with a fetal-type variant of the posterior cerebral artery (PCA) is often challenging. Since the complete occlusion rates achieved with the currently available treatment methods are unsatisfactory, we aimed to study the effectiveness of a double-balloon-assisted technique for these aneurysms. From September 2014 to August 2020, 6 consecutive patients with PcomA aneurysms with fetal-type PCAs and no previous treatment were treated with this technique at our institution (3 ruptured cases and 3 unruptured cases). The indication for this technique is that the neck of the aneurysm should significantly and broadly incorporate both the internal carotid artery and fetal-type PCA, such that a single-balloon remodeling and single stent would be inadequate to protect both the arteries. In all patients, the fetal-type PCAs were preserved without a stent and with adequate occlusion status. This double-balloon technique can be effective in the treatment of these aneurysms.

Small ruptured intracranial aneurysms are overrepresented at the anterior and posterior communicating artery: Results of a multiple regression analysis.

Background: Anterior communicating artery (AcomA) represents the most common location for ruptured intracranial aneurysms (rIAs). Approximately 50% of all rIAs are smaller than 7 mm, but factors that lead to rupture are multifactorial. The study investigates whether AcomA location represents an independent risk factor for small size at time of rupture (<7 mm) in a cohort of aneurysmal subarachnoid hemorrhage (aSAH) when controlling for known risk factors.Methods: The aSAH cohort was retrospectively searched from our institution charts. The cohort was dichotomized into small aneurysms (<7 mm) or large aneurysms (≥7 mm). Risk factors for rupture were identified according to the unruptured intracranial aneurysm treatment score (UIATS). These were sex, age, location, smoking, hypertension, alcohol abuse, aneurysm morphology, multiplicity, previous SAH, and family history. With size as independent variable, a multiple regression analysis was performed including UIATS risk factors.Results: One-hundred and seventy-six patients were included in the study. About 49.4% of the aneurysms were <7 mm. Multiple regression analysis demonstrated that aneurysms located at AcomA and posterior communicating artery (PcomA) was significantly more frequent smaller than 7 mm, compared to middle cerebral artery (P = 0.006), internal carotid artery (other than PcomA) (P = 0.013), and posterior circulation (P = 0.017), when controlling for risk factors.Conclusion: Ruptured AcomA and PcomA aneurysms are more frequent smaller than 7 mm compared to other locations. Patients with unruptured UIA at either AcomA or PcomA may be at increased risk of rupture even if the size of the aneurysm is small. Further studies are needed to confirm this finding.

The different recanalization rates of posterior communicating artery aneurysms with a fetal posterior communicating artery and anterior communicating artery aneurysms with a variation of the unilateral A1 segment.

Posterior communicating artery (PcomA) aneurysms are more likely to recanalize than anterior communicating artery (AcomA) aneurysms. However, it is still unclear whether the recanalization rate of these aneurysms is a result of involvement from the fetal posterior cerebral artery (fPCA) in PcomA aneurysms and variation of the unilateral A1 segment in AcomA aneurysms. The purpose of this study is to retrospectively evaluate the different recanalization rates between PcomA aneurysms with fPCA and AcomA aneurysms with a variation of the unilateral A1 segment. We retrospectively collected information regarding 214 patients, each with communicating segment aneurysms between January 2013 and January 2020. Follow-up documentation on clinical and imaging data was comparatively analyzed between variant types, and recanalization rates of the variant and normal types were analyzed by stratification. Of the 84 variant-type aneurysms (PcomA with fPCA and AcomA with a variation of the unilateral A1 segment, 41/43), complete recanalization occurred in 23 patients (27.4%), and it was significantly more likely to occur in PcomA aneurysms with fPCA (39.1%) than in AcomA aneurysms with a variation of the unilateral A1 segment (16.3%). Stent-assisted coil embolization (SACE) has been shown to reduce recanalization (OR =0.092, 95% CI: 0.011 to 0.790, P=0.03). Additionally, variant types and the normal type (non-fetal, 106, and bilateral A1 symmetry, 24) have different odds ratios (OR) of recanalization (P=0.04), and the OR of the variant subtypes was significant, unlike the normal type (P=0.49). This study suggests that PcomA aneurysms with fPCA are more likely to recanalize than AcomA aneurysms with a variation of the unilateral A1 segment.