Unruptured Posterior Communicating Artery Aneurysms Research Articles

Preoperative Simulation of Intraoperative Findings in Surgical Clipping of Posterior Communicating Artery Aneurysms Using T2-Weighted 3D Images.

Tentorium resection and detachment from the oculomotor nerve are sometimes required for surgical clipping of unruptured posterior communicating artery (PCoA) aneurysms. Using T2-weighted 3D images, we aimed to identify the preoperative radiological features required to determine the necessity of these additional procedures. We reviewed 30 patients with unruptured PCoA aneurysms who underwent surgical clipping and preoperative simulation using T2-weighted 3D images for measurement of the distance between the tentorium and aneurysm. Aneurysms were classified into superior type (superior to the tentorium) and inferior type (inferior to the tentorium). Seven patients (23%) underwent tentorium resection; all had the inferior type (superior vs. inferior, 0% vs. 33%, p = 0.071). In the 21 patients with the inferior type, the distance from the tentorium to the aneurysmal neck was 2.2 ± 1.1 mm and 0.0 ± 0.5 mm without and with tentorium resection (p < 0.01), respectively. An optimal cutoff value of ≤ +0.84 mm was identified for tentorium resection (area under the curve (AUC) = 0.96). Furthermore, 17 patients (57%) showed tight aneurysm attachment to the oculomotor nerve; all had the inferior type (0% vs. 81%, p < 0.01). The distance from the aneurysm tip to the tentorium was 1.1 ± 1.2 mm and -1.7 ± 1.4 mm without and with attachment (p < 0.01). The optimal cutoff value was ≤ +0.45 mm (AUC = 0.92). Measurement of the distance between the tentorium and aneurysmal neck or tip with T2-weighted 3D images is effective for preoperative simulation for surgical clipping of PCoA aneurysms.

Treatment of unruptured posterior communicating artery aneurysm: a comparison of clipping and coil embolization

Treatment of unruptured posterior communicating artery aneurysm: a comparison of clipping and coil embolization

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.

Added Predictive Values of Proton Density Magnetic Resonance Imaging on Posterior Communicating Artery Aneurysms and Surrounding Soft Tissues with Simple Classification.

Deciphering the anatomy of posterior communicating artery (PCoA) aneurysms in relation to surrounding structures is essential to determine adjuvant surgical procedures. However, it is difficult to predict surgical structures through preoperative imaging studies. We aimed to present anatomical structures using preoperative high-resolution three-dimensional proton densityweighted turbo spin-echo magnetic resonance (PDMR) imaging with simple classification. From January 2020 to April 2022, 30 patients underwent PDMR before microsurgical clipping for unruptured PCoA aneurysms in a single tertiary institute. We retrospectively reviewed the radiographic images and operative data of these patients. The structural relationship described by PDMR and intraoperative findings were compared. Subsequently, we classified aneurysms into two groups and analyzed the rate of adjuvant surgical procedures and contact with the surrounding structures. Correlations between preoperative PDMR predictions and actual intraoperative findings for PCoA aneurysm contact to the oculomotor nerve, temporal uncus, and anterior petroclinoid fold (APCF) reported a diagnostic accuracy of 0.90, 0.87, and 0.90, respectively. In 12 patients (40.0%), an aneurysm dome was located on the plane of the oculomotor triangle and was classified as the infratentorial type. Compared to the supratentorial type PCoA aneurysm, adjuvant procedures were required more frequently (66.7% vs. 22.2%, p=0.024) for infratentorial type PCoA aneurysm clipping. Preoperative PCoA aneurysm categorization using PDMR can be helpful for predicting surgical complexity and planning of microsurgical clipping.

Flow‐Diversion for Complex Posterior Communicating Artery Aneurysms Associated With a Fetal Posterior Circulation

Background Flow‐diverting stents (FDSs) are effective in treating complex intracranial aneurysms, including posterior communicating artery aneurysms. However, some studies have suggested FDSs have limited efficacy for posterior communicating artery aneurysms associated with a fetal posterior communicating artery (FPCoA). Methods A retrospective analysis of patients with FPCoA aneurysms treated using FDS intervention alone was performed. Only aneurysms in which the FPCoA originated from the neck or dome of the aneurysm, which were therefore not amenable to standard coil embolization, were included. Results Stand‐alone, single‐device FDSs were placed in 16 patients with unruptured posterior communicating artery aneurysms associated with an FPCoA. The device was sized to ensure excellent wall apposition, with a focus on expanding the device across the aneurysm neck to optimize flow diversion. Excellent angiographic results were achieved in 12 patients (75%), and all patients had satisfactory clinical outcomes, with complete obliteration of the aneurysm in 10 (62.5%). No patients required additional treatment. Nine patients had complete patency of the FPCoA, 4 had mildly decreased flow, 2 had markedly diminished flow, and 1 had FPCoA occlusion. In all 7 cases with decreased FPCoA flow, there was coincident increased flow in the P1 segment of the posterior cerebral artery. No patient developed posterior circulation ischemia. Mean follow‐up was 19.9 months. Conclusion Contrary to previous reports, the placement of FDSs was found to be a safe and effective treatment option for FPCoA aneurysms. The deployment technique of maximizing device expansion across the neck of the aneurysm may contribute to successful outcomes. Treatment using an FDS may be particularly useful for complex FPCoAs.

Premammillary artery infarction after microsurgical clipping of unruptured posterior communicating artery aneurysm: risk factors and surgical and anatomical considerations.

Posterior communicating artery (PCoA) aneurysm is common and sometimes requires microsurgery; however, as data on premammillary artery (PMA) infarction after clipping is scarce, we retrospectively reviewed cases of post-clipping PMA infarction to analyze incidence, independent risk factors of infarction, and anatomical considerations. Data from 569 consecutive patients who underwent microsurgical clipping for unruptured PCoA aneurysm between January 2008 and December 2020 were included. Patients were categorized into the normal or the PMA infarction group. Statistical analyses and comparisons between the two groups were used to determine the influence of various factors. The normal group included 515 patients while the PMA infarction group had 31. The mean length of hospital stay was significantly longer in the PMA infarction group (10.3 ± 9.1days) than in the normal group (6.5 ± 6.4days; p < 0.0001). The distribution of Glasgow Outcome Scale at discharge was significantly different between the two groups (p ≤ 0.0001) but was not so at 6months after discharge (p = 0.0568). Multivariate logistic regression analysis identified aneurysm size (odds ratio [OR], 1.194; 95% confidence interval [CI], 1.08-1.32; p = 0.0005) and medial direction of aneurysm (OR, 4.615; 95% CI, 1.224-17.406; p = 0.0239) as independent risk factors of post-clipping PMA infarction. Surgeons must beware of PMA infarction after clipping of large aneurysms that are medial in direction. Intraoperative verification of the patency of the PCoA and the PMA from various angles using various intraoperative methods can reduce morbidity due to PMA infarction.

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.

Endovascular versus surgical treatment for improvement of oculomotor nerve palsy caused by unruptured posterior communicating artery aneurysms

BackgroundThere is no consensus regarding the best treatment option for unruptured aneurysms of the posterior communicating artery (PCom) presenting with oculomotor nerve palsy (ONP). We aimed to assess predictors of...

Surgical Treatment of Posterior Communicating Artery Aneurysms: Hints and Precautions for Young Cerebrovascular Surgeons.

In spite of the advent of neurointerventional treatment, different clinical and anatomical features are still strong indications for clipping of posterior communicating artery (PComA) aneurysms. But the experience of young neurosurgeons is increasingly limited, and therefore providing technical operative guidelines is a fundamental prerequisite to achieve the best aneurysm exclusion and avoid perioperative complications. We describe a technical algorithm we use to teach young neurosurgeons how to approach carotid aneurysms that may help them develop a procedural memory and thus perform an efficient and safe surgery. We reviewed our last 10 years of institutional experience of > 150 cases of clipping ruptured and unruptured PComA aneurysms, analyzing our technical refinements and the difficulties in teaching residents and young neurosurgeons how to establish fundamental key points and design a didactic algorithm that includes operative instructions and safety rules. We recognized seven pragmatic technical key points regarding craniotomy, cisternostomy, proximal and distal control, aneurysm neck dissection, preservation of neurovascular structures, and clipping to use in a didactic algorithm for teaching residents and as operative instructions for inexperienced neurosurgeons. In the setting of clipping PComA aneurysms, respect for surgical rules is of paramount importance to perform an efficacious and safe procedure and ensure the best aneurysm exclusion and preservation of neurovascular structures.

Surgery of a Posterior Communicating Artery Aneurysm with Fetal-Type Circulation

AbstractInadvertent occlusion of a fetal-type posterior communicating artery in aneurysm surgery could result in posterior circulation infarction and neurological morbidity. The case of a patient with an unruptured posterior communicating artery aneurysm with lateral projection and a fetal-type posterior communicating artery is presented. The utility of the carotid-oculomotor window as a surgical corridor to safely find the fetal-type posterior communicating artery is discussed.

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.

Clipping treatment of posterior communicating artery aneurysms associated with arteriosclerosis and calcification: A single center study of 136 cases.

It is widely acknowledged that arteriosclerosis and calcification of the parent artery and aneurysm neck make it difficult to clip posterior communicating artery (PCoA) aneurysms. A total of 136 cases of PCoA aneurysms accompanied by arteriosclerosis and calcification were collected and treated with clipping in the present study. Of the 136 patients, 112 were females (82.4%) and 24 were males (17.6%), with ages ranging from 37 to 76 years (mean age, 60.2 years). Rupture of a PCoA aneurysm was identified in 132 cases (97.1%), and there were 4 cases of unruptured PCoA aneurysms (2.9%). According to the severity of arteriosclerosis and calcification, the aneurysms were divided into type I, II or III. The treatment of type I aneurysms achieved the best curative effect. It is difficult to temporarily occlude type II and III aneurysms during surgery, and temporary occlusion failed in almost 50% of cases. Types II and III were prone to intraoperative aneurysm ruptures. A significantly higher rate of intraoperative aneurysm rupture was seen in type III compared with type II cases. Type II and III cases were more likely to be treated using a fenestrated clip for aneurysm clipping compared with type I cases, and fenestrated clips were used significantly more frequently in type III cases compared with type II cases. Arteriosclerosis and calcification were likely to affect the prognosis of patients, particularly in cases with type III arteriosclerosis and calcification of the parent artery and aneurysm neck. Therefore, the stratification of the arteriosclerosis and calcification of the parent artery and aneurysm neck into types I-III can guide the intraoperative aneurysm clipping strategy, aid in choosing the correct clips, and inform predictions of the occurrence of rupture and hemorrhage, as well as the prognosis for aneurysms.

Brain aneurysm patients seen in Harare, Zimbabwe: cases review and review of literature 2012-2014

Objectives: The study aimed to look at the demographic information, size and location of intracranial aneurysms, treatment rendered and the outcomes in Zimbabwe.Design: Retrospective study.Setting: Parirenyatwa Group of Hospitals and Avenues Clinic, Harare, Zimbabwe.Subjects: Adult intracranial aneurysm patients.Interventions: Craniotomy and aneurysm clipping.Results: Seventeen patients were seen during the period of study. Twelve were female patients while five were male with a male to female ratio of 1:2. The age ranged from 25-73years, with the average age being 50 and median being 58 years. Fourteen patients were black Africans, two patients were Caucasian while one was Chinese. Ten of the seventeen (58.8%) had hypertension while two had a history of aneurysms in the family. Sixteen presented after rupture of the aneurysm while one was seen at diagnosis with an unruptured posterior communicating artery aneurysm. Most aneurysms were in the anterior communicating artery and the internal carotid artery territories (35% each). Nine of the seventeen patients did undergo craniotomy and clipping of the aneurysm. Three patients had intra-operative rupture of the aneurysm.Conclusion: There is need to improve patient and medical personnel education and so that more patience with this condition are seen and diagnosed in hospitals. This will also help to make surgery for brain aneurysm more acceptable in Zimbabwe.

The Resolution of Oculomotor Nerve Palsy Caused by Unruptured Posterior Communicating Artery Aneurysms: A Cohort Study and Narrative Review.

Recovery of oculomotor nerve palsy after microsurgical and endovascular treatment has been studied in numerous small series of predominantly ruptured aneurysms. Little consideration has been given to the distinction between ruptured and unruptured aneurysms. This study examines the influence of treatment modality on oculomotor palsy recovery as a result of unruptured posterior communicating artery aneurysms. Patients who presented between 2003 and 2015 with an oculomotor palsy secondary to an unruptured posterior communicating artery aneurysm were identified from the hospital database. A keyword search for "posterior communicating artery aneurysm" and "oculomotor nerve palsy OR third nerve palsy" using the PubMed database was performed for the narrative review. The cohort study and narrative review identified 15 and 179 eligible patients, respectively. Surgically treated patients in the cohort study did not have a significantly better rate of complete palsy resolution than those who had been coiled (P= 0.08). In the review, clipping of the aneurysm resulted in a higher rate of complete palsy resolution (70.0%; 95% confidence interval [CI], 60.7%-79.3%) than did coiling (46.5%; 95% CI, 36.0%-57.0%). Patients who presented with an aneurysm <7 mm had a higher rate of complete palsy resolution compared with aneurysms >7 mm (68.6%; 95% CI, 57.7%-79.5% vs. 44.3%; 95% CI, 32.7%-55.9%). Patients presenting with a complete palsy (49.4%; 95% CI, 38.6%-60.2%) had a lower rate of recovery than did those with a partial palsy (71.4%; 95% CI, 60.2%-82.6%). In this narrative review, surgical clipping of unruptured posterior communicating artery aneurysms was associated with a higher rate of associated oculomotor palsy recovery than was endovascular treatment.

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.

Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy.

OBJECT Unruptured posterior communicating artery (PCoA) aneurysms with oculomotor nerve palsy (ONP) have a very high risk of rupture. This study investigated the hemodynamic and morphological characteristics of intracranial aneurysms with high rupture risk by analyzing PCoA aneurysms with ONP. METHODS Fourteen unruptured PCoA aneurysms with ONP, 33 ruptured PCoA aneurysms, and 21 asymptomatic unruptured PCoA aneurysms were included in this study. The clinical, morphological, and hemodynamic characteristics were compared among the different groups. RESULTS The clinical characteristics did not differ among the 3 groups (p > 0.05), whereas the morphological and hemodynamic analyses showed that size, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, normalized wall shear stress (WSS), and percentage of low WSS area differed significantly (p < 0.05) among the 3 groups. Furthermore, multiple comparisons revealed that these parameters differed significantly between the ONP group and the asymptomatic unruptured group and between the ruptured group and the asymptomatic unruptured group, except for size, which differed significantly only between the ONP group and the asymptomatic unruptured group (p = 0.0005). No morphological or hemodynamic parameters differed between the ONP group and the ruptured group. CONCLUSIONS Unruptured PCoA aneurysms with ONP demonstrated a distinctive morphological-hemodynamic pattern that was significantly different compared with asymptomatic unruptured PCoA aneurysms and was similar to ruptured PCoA aneurysms. The larger size, more irregular shape, and lower WSS might be related to the high rupture risk of PCoA aneurysms.

Endovascular flow diversion therapy for an actively hemorrhaging aneurysm after intraoperative rupture

We report a 56-year-old woman who had an unruptured posterior communicating artery aneurysm. Given the size and location of the aneurysm, as well as her history of smoking and age, she received endovascular treatment with the pipeline embolization device (PED; ev3 Endovascular, Plymouth, MN, USA), complicated by intraoperative rupture (IOR). Flow diversion therapy with the PED has become an increasingly popular method of aneurysmal embolization and parent vessel remodeling. While its on-label approval is for large unruptured aneurysms of the internal carotid artery, success in off-label scenarios has been reported, including ruptured aneurysms. IOR complicates endovascular aneurysm treatment and can cause devastating morbidity or mortality, necessitating acute embolization of the hemorrhaging aneurysm. This patient illustrates the feasibility of treating an IOR with a stand-alone flow diversion device by using PED.

Third nerve palsy caused by compression of the posterior communicating artery aneurysm does not depend on the size of the aneurysm, but on the distance between the ICA and the anterior–posterior clinoid process

ObjectiveThird nerve palsy (TNP) caused by a posterior communicating artery (PCoA) aneurysm is a well-known symptom of the condition, but the characteristics of unruptured PCoA aneurysm-associated third nerve palsy have not been fully evaluated. The aim of this study was to analyze the anatomical features of PCoA aneurysms that caused TNP from the viewpoint of the relationship between the ICA and the skull base. MethodsForty-eight unruptured PCoA aneurysms were treated surgically between January 2008 and September 2013. The characteristics of the aneurysms were evaluated. ResultsThirteen of the 48 patients (27%) had a history of TNP. The distance between the ICA and the anterior–posterior clinoid process (ICA–APC distance) was significantly shorter in the TNP group (p<0.01), but the maximum size of the aneurysms was not (p=0.534). ConclusionRelatively small unruptured PCoA aneurysms can cause third nerve palsy if the ICA runs close to the skull base.

Augmented Reality in the Surgery of Cerebral Aneurysms

Augmented reality is the overlay of computer-generated images on real-world structures. It has previously been used for image guidance during surgical procedures, but it has never been used in the surgery of cerebral aneurysms. To report our experience of cerebral aneurysm surgery aided by augmented reality. Twenty-eight patients with 39 unruptured aneurysms were operated on in a prospective manner with augmented reality. Preoperative 3-dimensional image data sets (angio-magnetic resonance imaging, angio-computed tomography, and 3-dimensional digital subtraction angiography) were used to create virtual segmentations of patients' vessels, aneurysms, aneurysm necks, skulls, and heads. These images were injected intraoperatively into the eyepiece of the operating microscope. An example case of an unruptured posterior communicating artery aneurysm clipping is illustrated in a video. The described operating procedure allowed continuous monitoring of the accuracy of patient registration with neuronavigation data and assisted in the performance of tailored surgical approaches and optimal clipping with minimized exposition. Augmented reality may add to the performance of a minimally invasive approach, although further studies need to be performed to evaluate whether certain groups of aneurysms are more likely to benefit from it. Further technological development is required to improve its user friendliness.

Analysis of Morphologic and Hemodynamic Parameters for Unruptured Posterior Communicating Artery Aneurysms with Oculomotor Nerve Palsy

Posterior communicating artery aneurysms with oculomotor nerve palsy may imply sudden enlargement of the aneurysm sac and have a high risk of rupture. Our aim was to identify the morphologic and hemodynamic parameters in this special period of aneurysm progression and to assess related rupture risk indices. We analyzed the morphologic and hemodynamic parameters of 9 unruptured posterior communicating artery aneurysms with oculomotor nerve palsy and 9 ruptured ones. The morphologic parameters were measured and calculated from patient-specific 3D rotational angiographic images, and pulsatile computational fluid dynamic simulation was then performed for hemodynamic parameters. There was no significant statistical difference between the 2 groups in size, aspect ratio, size ratio, aneurysm angle, or vessel angle; analysis only demonstrated a significantly lower wall shear stress of the aneurysm wall in the symptomatic unruptured group in hemodynamics (P = .024), whereas there were no differences in wall shear stress of the parent artery, low wall shear stress area, and oscillatory shear index. From morphologic and hemodynamic perspectives, we demonstrated that posterior communicating artery aneurysms with oculomotor nerve palsy had characteristics similar to those of ruptured ones, except for lower wall shear stress on the aneurysm wall, which might indicate an important role in aneurysm rupture.