Anterior Communicating Artery Aneurysm Surgery through the Orbitopterional Approach: Long-Term Follow-Up in a Series of 75 Consecutive Patients

The risk factors of postoperative infarction after surgical clipping of unruptured anterior communicating artery aneurysms: anatomical consideration and infarction territory

PURPOSE

An anterior communicating artery is a common location for both ruptured and unruptured intracranial aneurysms, and microsurgery is sometimes necessary for their successful treatment. However, postoperative infarction should be considered during clipping due to the complex surrounding structures of anterior communicating artery aneurysms. This study aimed to evaluate the risk factors of postoperative infarction after surgical clipping of unruptured anterior communicating artery aneurysms and its clinical outcomes.

METHODS

The data of patients who underwent microsurgical clipping of an unruptured anterior communicating artery aneurysm in our hospital between January 2008 and December 2020 were retrospectively analyzed. The patients' demographic data, anatomical features of the anterior communicating artery complex and aneurysm, surgical technique, characteristics of postoperative infarction, and its clinical course were evaluated.

RESULTS

Notably, among 848 patients, 66 (7.8%) and 34 (4%) patients had radiologic and symptomatic infarctions, respectively. Univariate and multivariate logistic regression analyses showed that hypertension (odds ratio (OR), 1.99; [Formula: see text]), previous stroke (OR, 3.89; [Formula: see text]), posterior projection (OR, 5.58; [Formula: see text]), aneurysm size (OR, 1.17; optimal cut-off value, 6.14 mm; [Formula: see text]), and skull base-to-aneurysm distance (OR, 1.15; optimal cut-off value, 11.09 mm; [Formula: see text]) were associated with postoperative infarction. In the pterional approach, a closed A2 plane was an additional risk factor (OR, 1.88; [Formula: see text]). Infarction of the subcallosal and hypothalamic branches was significantly associated with symptomatic infarction ([Formula: see text]).

CONCLUSION

Hypertension, previous stroke, posteriorly projecting aneurysms, aneurysm size, and highly positioned aneurysms are independent risk factors for postoperative infarction during surgical clipping of an unruptured anterior communicating artery aneurysm. Additionally, a closed A2 plane is an additional risk factor of postoperative infarction in patients undergoing clipping via the pterional approach.

Variations of perforating arteries of anterior communicating artery in cases with anterior communicating artery aneurysms: a cadaveric anatomical study

PURPOSE

In terms of postoperative morbidity and mortality, preservation of the perforating arteries branching from the anterior communicating artery (ACoA) during clipping is particularly imperative in patients with ACoA aneurysm. In the present study, we aimed to investigate whether perforating arteries originated from ACoA were pushed away in a different location in patients with ACoA aneurysm. Furthermore, if they did so, we aimed to identify the direction in which they were dislocated and how the perforating arteries could be preserved during clipping.

METHODS

Herein, we categorized 40 brains obtained from cadavers into two groups. The first (n = 26) and second (n = 14) groups included cases without and with ACoA aneurysms, respectively. After completing the preparation procedure, the brains were dissected using surgical microscope and the relevant anatomical region was examined and photographed. Finally, statistical analyses were performed on the data and the results were documented.

RESULTS

In the aneurysms with posterior and superior projections, the perforators appeared to be pushed away inferiorly and were frequently noted at the anteroinferior part of the aneurysm neck. Most of the cases, where one of the A1s was larger at one side, the perforating arteries arose from the larger A1 side.

CONCLUSION

The mortality and morbidity associated with damage to the perforators can be reduced by approaching the patient from the dominant A1 side and pursuing the perforators primarily at the anteroinferior part of the aneurysm neck in the aneurysms with superior and posterior projections.

Microsurgical Treatment of Unruptured Anterior Communicating Artery Aneurysms: Approaches and Outcomes in a Large Contemporary Series and Review of the Literature

BACKGROUND

With advances in endovascular techniques, the relative roles of microsurgery and endovascular therapy in the management of intracranial aneurysms have become less clear, and data regarding treatment-specific outcomes are increasingly important.

OBJECTIVE

To describe our experience with microsurgery in a large series of unruptured anterior communicating artery aneurysms (ACOMMAAs) and detail our treatment decision-making process based on individual aneurysm morphology.

METHODS

We retrospectively reviewed unruptured ACOMMAAs treated microsurgically at our center between 1997 and 2018, recording aneurysm size, surgical approach, occlusion rates, neurological outcomes, and complications.

RESULTS

We treated 300 unruptured ACOMMAAs in 300 patients, mean age 49 yr, 180 (60.0%) female, including 245 (81.7%) small, 50 (16.7%) large, and 5 (1.7%) giant aneurysms. Most underwent a pterional approach (253, 84.3%), with orbitozygomatic or anterior interhemispheric approaches in 35 (11.7%) and 12 (4%), respectively. Greater than 95% occlusion was achieved in 284 (94.7%), 90% to 95% occlusion in 13 (4.3%), and 3 (1.0%) underwent wrapping. Serious complications occurred in 3 patients (1.0%) resulting in 2 deaths (0.7%), and minor complications in 12 (4.0%). At final follow-up, good neurological outcome was observed in 297 (99.0%) patients.

CONCLUSION

Given clinical equipoise regarding optimal treatment of unruptured ACOMMAAs, this work provides a benchmark for achievable microsurgical outcomes. Future surgical/endovascular studies should separate results of ruptured and unruptured lesions and describe aneurysm morphology to allow for better comparison of outcomes between treatments. We suggest that open microsurgery represents an important option for select, morphologically complex ACOMMAAs, and that a multidisciplinary approach offers optimal patient outcomes.

Recurrence and retreatment of anterior communicating artery aneurysms after endovascular treatment: a retrospective study

Background

Surgical treatment of anterior communicating artery (Acom) aneurysm is challenging due to anatomic complexity. We aimed to describe our experiences with endovascular treatment (EVT) of Acom aneurysms, and to evaluate the incidence and risk factors of recurrence and retreatment.

Methods

The study comprised 260 patients who were treated at a single center between January 2010 and December 2018. Patients who had EVT, including stent-assisted coiling of Acom aneurysms, were included. All medical records were retrospectively reviewed. The incidence and risk factors of recurrence and retreatment were evaluated. Univariate and multivariate analysis were conducted.

Results

Recurrence of Acom aneurysms occurred in 38 (14.6%) patients. Mean follow-up duration was 27 months (range 1–110). Multivariate logistic regression indicated that ruptured aneurysm (odds ratio [OR] 3.55, P = 0.001), dome direction (anterior) (OR 3.86, P = 0.002), maximal diameter (OR 1.19, P = 0.02), and mean age (OR 0.96, P = 0.02) were independent risk factors for aneurysm recurrence. Of 38 cases of recurrence, 10 (3.8%) patients underwent retreatment. Ruptured aneurysm (OR 14.7, P = 0.004), maximal diameter (OR 1.56, P = 0.02), inflow angle (OR 1.04, P = 0.03), and Raymond-Roy classes II and III (OR 6.19, P = 0.03) showed significant relation to retreatment in multivariate logistic regression analysis.

Conclusions

In our study, recurrence rate of Acom aneurysms after EVT was 14.6%. Rupture, anterior dome direction, maximal diameter, and mean age were significantly associated with recurrence. Retreatment rate of recurrent Acom aneurysms after EVT was 3.8%. Patients with Acom aneurysms with large inflow, rupture, large size, or incomplete occlusion may be at a high risk of retreatment of recurring aneurysm.

Anatomical triangles defining routes to anterior communicating artery aneurysms: the junctional and precommunicating triangles and the role of dome projection

OBJECTIVE

Anterior communicating artery (ACoA) aneurysms are common intracranial aneurysms. Despite advances in endovascular therapy, microsurgical clipping remains an important treatment for aneurysms with broad necks, large size, intraluminal thrombus, complex branches, or previous coiling. Anatomical triangles identify safe corridors for aneurysm access. The authors introduce the A1-A2 junctional triangle and the A1-A1 precommunicating triangle and examine relationships between dome projection, triangular corridors of access, and surgical outcomes.

METHODS

Preoperative catheter and CT angiograms were evaluated to characterize aneurysm dome projection. Aneurysm projection was categorized into quadrants and octants. Preoperative, intraoperative, and postoperative factors were correlated to aneurysm dome projection and patient outcomes using univariate and multivariate analyses.

RESULTS

A total of 513 patients with microsurgically treated ACoA aneurysms were identified over a 13-year period, and 400 had adequate imaging and follow-up data for inclusion. Surgical clipping was performed on 271 ruptured and 129 unruptured aneurysms. Good outcomes were observed in 91% of patients with unruptured aneurysms and 86% of those with ruptured aneurysms, with a mortality rate < 1% among patients with unruptured aneurysms. Increasing age (p < 0.01), larger aneurysm size (p = 0.03), and worse preoperative modified Rankin Scale score (p < 0.01) affected outcomes adversely. Aneurysms projecting superiorly and posteriorly required dissection in the junctional triangle, and multivariate analysis demonstrated worse clinical outcomes in these patients (p < 0.01).

CONCLUSIONS

Anteriorly and inferiorly projecting aneurysms involve only the precommunicating triangle, are simpler to treat microsurgically, and have more favorable outcomes. Superior and posterior dome projections make ACoA aneurysms more difficult to visualize and require opening the junctional triangle. Added visualization through the junctional triangle is recommended for these aneurysms in order to facilitate dissection of efferent branch arteries, careful clip application, and perforator preservation. Dome projection can be determined preoperatively from images and can help anticipate dissection routes through the junctional triangle.

Injury of Corticospinal Tract in a Patient with Subarachnoid Hemorrhage as Determined by Diffusion Tensor Tractography: A Case Report

We report diffusion tensor tractography (DTT) of the corticospinal tract (CST) in a patient with paresis of all four limbs following subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) after the rupture of an anterior communicating artery (ACoA) aneurysm rupture. The 73-year-old female was admitted to our emergency room in a semi-comatose mental state. After coil embolization-an acute SAH treatment-she was transferred to our rehabilitation department with motor weakness development, two weeks after SAH. Upon admission, she was alert but she complained of motor weakness (upper limbs: MRC 3/5, and lower limbs: MRC 1/5). Four weeks after onset, DTT showed that the bilateral CSTs failed to reach the cerebral cortex. The left CST demonstrated a wide spread of fibers within the corona radiata as well as significantly lower tract volume (TV) and higher fractional anisotropy (FA) as well as mean diffusivity (MD) compared to the controls. On the other hand, the right CST shifted to the posterior region at the corona radiata, and MD values of the right CST were significantly higher when compared to the controls. Changes in both CSTs were attributed to vasogenic edema and compression caused by untreated hydrocephalus. We demonstrate in this case, two different pathophysiological entitles, contributing to this patient's motor weakness after SAH.

Clinical and morphological profile of aneurysms of the anterior communicating artery treated at a neurosurgical service in Southern Brazil

Background:

The aim of the study was to characterize the clinical profile of patients with anterior communicating artery (ACoA) aneurysms and examine potential correlations between clinical findings, aneurysm morphology, and outcome.

Methods:

A review of medical records and diagnostic neuroimaging reports of patients treated at a neurosurgical service in Porto Alegre, Brazil, between August 2008 and January 2015 was performed.

Results:

During the period, 100 patients underwent surgery for ACoA aneurysms. Fifteen had unruptured aneurysms and 85 had ruptured aneurysms. Ruptured aneurysms had a higher aspect ratio than unruptured ones (2.37 ± 0.71 vs. 1.93 ± 0.51, P = 0.02). Intraoperative rupture occurred in 3%, and temporary clipping was performed in 15%. Clinical vasospasm occurred in 43 patients with ruptured aneurysms (50.6%). Overall, mortality was 26%; 25 patients in the ruptured group (29.4%) and one in the unruptured group (6%). The Glasgow Outcome Scale (GOS) was favorable (GOS 4 or 5) in 54% of patients, significantly more so in those with unruptured aneurysms (P = 0.01). In patients with ruptured aneurysms, mortality was associated with preoperative Hunt and Hess (HH) score (P < 0.001), hydrocephalus (P < 0.001), and clinical complications (P < 0.001). Unfavorable outcomes were associated with HH score (P < 0.001), Fisher grade (P = 0.015), clinical vasospasm (P = 0.012), external ventricular drain (P = 0.015), hydrocephalus (P < 0.001), and presence of clinical complications (P = 0.001). In patients with unruptured aneurysms, presence of clinical complications was the only factor associated with mortality (P < 0.001).

Conclusion:

Despite advances in the management of subarachnoid hemorrhage and surgical treatment of aneurysms, mortality is still high, especially due to clinical complications.

Prospective factors of temporary arterial occlusion during anterior communicating artery aneurysm repair

INTRODUCTION

This study was undertaken to determine variables that could predict, in the perioperative period of anterior communicating artery (ACom) aneurysms surgeries, the likelihood of postoperative sequelae and complications, after temporary arterial occlusion (TAO).

PATIENTS AND METHODS

In a universe of 32 patients submitted to ACom aneurysm repair in the last 7 years, 21 needed TAO intraoperatively, and had their data examined retrospectively.

RESULTS

Aneurysms larger than 7 mm were more likely to be treated with longer TAO time than small aneurysms, (p < 0.0001). There was no statistical correlation between time of occlusion and outcome. Age, Glasgow Coma Scale at initial evaluation, and Fisher scale at first CT scanning were independent factors of unfavorable outcome (p < 0.001). Meanwhile gender, tobacco addiction, obesity, arterial hypertension, dyslipidemia, location of TAO (A1 or A2), intraoperative rupture (IR) and the aneurysm size were not identified as independent prognostic factors.During follow-up period, two thirds of the patients had a favorable outcome, accomplishing normal daily life activities without major complications. Most patients developed clinical vasospasm (66.6 %), with 19 % of the patients harboring a severe disease. Delayed ischemic neurological deficit was observed in 28.5 %, without any statistical correlation to time of TAO or IR.

CONCLUSION

TAO during ACom aneurysm repair does not seem to add more morbidities to the procedure, and is not an independent prognostic factor.

International Subarachnoid Trial in the Long Run

The International Subarachnoid Trial (ISAT), the largest prospective randomized study into endovascular and neurosurgical treatment of ruptured intracranial aneurysms, recently reported long-term follow-up in The Lancet Neurology. In this cohort, the risk of death at 5 years was significantly lower in the coiled group, but the proportion of survivors who were independent was not statistically different between the groups, and rebleeding was higher in the coiled group. This article critically evaluates the long-term ISAT data from an evidence-based perspective and places it in the context of the overall approach to treatment of ruptured intracranial aneurysms. ISAT has been a strong driver of change in the management of ruptured aneurysms. Nevertheless, the evidence for the superiority in coiling in the long term should not be assumed from ISAT data alone. Potential biases of patient characteristics and national referral patterns, as well as the methodological problems already described from the original trial, contribute to the difficulty in interpreting differences in long-term outcomes. These new data should be regarded as Level 2b evidence, suitable for treatment recommendations but not guidelines.