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

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

BACKGROUND

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.

METHODS

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).

RESULTS

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).

CONCLUSIONS

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.

An understimated maneuver for oculomotor nerve palsy due to posterior communicating artery aneurysm: the opening of the anterior petroclinoid ligament. A technical note

Posterior communicating artery aneurysms (PcomAs) present with oculomotor nerve (OMN) palsy in 20-30% of cases, and the sudden onset of OMN palsy has to raise the suspicion of rupture, until proven otherwise. The surgical technique is described in a stepwise fashion. An illustrative case is reported: a 57-year-old female was admitted to our department with the diagnosis of a right sided-PcomA. Three months before the admission, when she harbored with the acute onset of complete ptosis, diplopia, orbital pain, impairment of the medial, upward, and downward gaze, with no pupil dysfunction. The origin of the Pcom and the neck of the aneurysm were easily identified and the aneurysm was clipped. Then, we followed the OMN and cut for less than 4 mm the above-lying anterior petroclinoid ligament (APL) to obtain nerve release. Although few cases are described in the literature, and ours represents a single case, we support that this maneuver should be introduced in the clinical practice of expert neurosurgeons dealing with vascular pathologies, such as the opening of the falciform ligament occurs for the decompression of the optical nerve.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Risks for Oculomotor Nerve Palsy and Time to Recovery After Surgical Clipping of Posterior Communicating Artery Aneurysms: A Multicenter Retrospective Cohort Study

BACKGROUND

Aneurysms of the posterior communicating segment of carotid artery (PcomA) have a high risk of rupture; when these nonruptured aneurysms are associated with oculomotor nerve palsy (ONP), the risk of rupture increases compared with asymptomatic nonruptured PcomA.

OBJECTIVE

To retrospectively analyze the risk factors involved in ONP secondary to PcomA aneurysm and to study the factors involved in the recovery time of ONP once it is established.

METHODS

This was a retrospective study of patients from 10 neurosurgery centers from October 2008 to December 2020. We analyzed age at diagnosis, presence of compressive neuropathy of the oculomotor nerve, presence of aneurysm rupture, largest aneurysm diameter, aneurysm projection, smoking, hypertension, diabetes, time between diagnosis and surgical treatment, as well as the outcome.

RESULTS

Approximately 1 in 5 patients (119/511 23.3%) with a PcomA presented with ONP. We found that patients with aneurysms measuring greater than or equal to 7.5 mm were 1.6 times more likely to have ONP than those with aneurysms smaller than 7.5 mm. In our study, the prevalence of smoking in the PcomA + ONP group was 57.76%, and we also found that smokers were 2.51 times more likely to develop ONP. A total of 80.7% showed some degree of improvement, and 45.4% showed complete improvement with a median recovery time of 90 days.

CONCLUSION

This study showed that 80.7% of patients with PcomA aneurysms undergoing surgical treatment with aneurysm clipping showed some degree of improvement of the ONP, with a median time to recovery between 90 and 120 days.

Small symptomatic anterior communicating artery aneurysms: report of three cases and literature review

PURPOSE

Given the anatomical relationship between the ACom complex and the optic nerve, small aneurysms of the ACom can present with visual symptoms.

CASE REPORTS

We summarize and illustrate the clinical course of three patients with symptomatic small ACom aneurysms and collect similar other cases reported.

RESULTS

Ten patients with small unruptured visually symptomatic anterior communicating artery aneurysms were found in the literature. Including three patients herein reported, the mean age at presentation was 56. The most common visual symptoms were bitemporal vision loss and/or a decrease in visual acuity.

CONCLUSION

Unruptured aneurysms of the anterior communicating artery can present with visual symptoms due to compression of optic pathways, even at a small size. Prompt recognition and treatment of such a condition are paramount as new onset of visual symptoms can signify impending rupture akin to small PCom aneurysms compressing the third nerve. We discuss a few pitfalls of clipping small ACom aneurysms compressing the optic nerve.

Recovery of oculomotor nerve palsy after endovascular management of posterior communicating artery aneurysms

BACKGROUND

Oculomotor nerve palsy (ONP) is a common clinical presentation of posterior communicating artery (PcomA) aneurysms. It remains unclear if patients have a better rate of recovery after surgical clipping or endovascular coiling.

OBJECTIVES

The main objectives of this study were to assess the overall rate of ONP recovery after endovascular coiling of PcomA aneurysms, as well as to determine the associated predictive factors of oculomotor nerve recovery.

METHOD

We retrospectively evaluated the demographic, clinical, and radiological characteristics and the outcome of consecutive patients presenting with PcomA aneurysms treated by endovascular coiling from January 2012 to November 2016 with at least 1 year clinical and radiological follow-up. Statistical analysis was applied to determine the association between ONP recovery and the demographic, clinical and radiological variables.

RESULTS

A total of 91 patients with PcomA aneurysms were treated endovascularly. Thirty-four patients (22 women and 12 men) with ONP related to PcomA aneurysms were included. The mean age of the patients was 49.8 years. Subarachnoid haemorrhage was present in 27 patients. The mean aneurysm size was 6.7 mm. The overall rate of recovery was 88.2%. Complete nerve recovery was seen in 16 (47%) patients and partial recovery was observed in 14 (41.2%) patients, whilst 4 (11.8%) patients remained unchanged after treatment. The non-posterolateral direction of the aneurysm showed a tendency towards better recovery compared to the posterolateral projection (p = 0.06).

CONCLUSION

Endovascular coiling of PcomA aneurysms in patients with ONP resulted in a cure or improvement of oculomotor nerve dysfunction in the majority of patients.

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

Background

There 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 ONP recovery in a multicenter series of consecutive patients.

Materials and methods

A retrospective review of prospective databases in three tertiary neurosurgical centers was carried out, selecting patients with ONP caused by unruptured PCom aneurysms, treated by surgical clipping or embolization, between January 2006 and December 2013. Patient files and imaging studies were used to extract ophthalmological assessments, treatment outcomes, and follow-up data. Predictors of ONP recovery during follow-up were explored using univariate and multivariate analyses.

Results

We identified 55 patients with a median ONP duration before treatment of 11 days (IQR 4.5–18); the deficit was complete in 27 (49.1%) and incomplete in 28 (50.9%) cases. Median aneurysm size was 7 mm (IQR 5–9). Twenty-four (43.6%) patients underwent surgical clipping and 31 (56.4%) embolization as the primary treatment. Overall, ONP improved in 40 (72.7%) patients and persisted/recurred in 15 (27.3 %). Surgery, interval to complete treatment <4 weeks, aneurysm recurrence during follow-up, and retreatment during follow-up were significantly correlated with ONP outcome in the univariate analysis. In the multivariate analysis, independent predictors of ONP improvement were interval to complete treatment <4 weeks (OR 5.15, 95% CI 1.37 to 23.71, p=0.015) and aneurysm recurrence during follow-up (OR 0.1, 95% CI 0.02 to 0.47, p=0.003).

Conclusion

There was no significant difference in ONP recovery between surgical clipping and embolization. The best predictor for ONP recovery was timely, complete, and durable aneurysm exclusion.

Impact of the Intracranial Course of Internal Carotid Artery on Optimal Surgical Approach for Posterior Communicating Artery Aneurysms

BACKGROUND

The anterior temporal approach (ATA) has been reported as suitable for surgical clipping of posteriorly projecting internal carotid artery (ICA) aneurysms. As the ICA follows a variable course, tortuosity of the ICA may affect visualization of the aneurysm. The aim of this study was to investigate the impact of the intracranial course of the ICA and aneurysm projection on surgical approach.

METHODS

Consecutive patients with posterior communicating artery aneurysms treated with clipping at our hospital between May 2015 and April 2018 were retrospectively reviewed. When the transsylvian approach (TSA) could not achieve adequate exposure of the aneurysm, the ATA was subsequently performed. Distance between the ICA and the anterior and posterior clinoid line, angle between the midline and the C1 segment of the ICA, and aneurysm projection were compared between ATA and TSA groups.

RESULTS

Of 52 patients (40 ruptured, 12 unruptured), 12 were in the ATA group, and 40 were in the TSA group. Mean ICA-anterior and posterior clinoid distance was significantly shorter in the ATA group than in the TSA group (P = 0.002), and mean midline-C1 angle was significantly larger in the ATA group than in the TSA group (P < 0.0001). The ATA group was associated with a greater frequency of posteriorly projecting aneurysms (12 of 12; 100%) than the TSA group (9 of 40; 22.5%) (P < 0.00001).

CONCLUSIONS

A low-lying, laterally projecting intracranial ICA and posteriorly projecting aneurysm are predictors of the necessity for the ATA in the surgical clipping of posterior communicating artery aneurysms.

Clinical Significance of Circumferential Aneurysmal Wall Enhancement in Symptomatic Patients with Unruptured Intracranial Aneurysms: a High-resolution MRI Study

BACKGROUND AND PURPOSE

The estimates on the risk of rupture of intracranial aneurysms remain a controversial topic. Circumferential aneurysmal wall enhancement (CAWE) on vessel wall magnetic resonance imaging (MRI) has been described in unstable aneurysms. Sentinel headaches and third nerve palsy are possible symptoms prior to the rupture of intracranial aneurysms. In this study, we aimed to demonstrate that CAWE could be associated with these symptoms.

METHODS

We performed a retrospective analysis of consecutive symptomatic or asymptomatic patients with unruptured intracranial aneurysms who were examined by high-resolution MRI from October 2014 to November 2016. Two experienced neurovascular radiologists read the images independently and determined whether there was CAWE of the unruptured intracranial aneurysms. Then, we compared variable factors between patients with and without symptoms through univariate comparison and multivariable logistic regression analyses.

RESULTS

A total of 45 unruptured intracranial aneurysms were detected in 37 patients. The agreement between 2 experienced readers for CAWE was good (kappa = 0.82; 95% confidence interval 0.66-0.99). CAWE of unruptured intracranial aneurysm was more frequently observed in symptomatic than in asymptomatic patients (16/23, 69.6% versus 6/22, 27.3%, respectively, P < 0.05). The CAWE was the only independent factor associated with symptoms in the multivariable logistic regression analysis (odds ratio 5.17; 95% confidence interval 1.30-20.52; P = 0.02).

CONCLUSIONS

Our study demonstrates that CAWE correlated with sentinel headaches and third nerve palsy caused by unruptured aneurysms, and this may be an additional clue to distinguish the cause of these symptoms.