Endovascular Management of Distal Anterior Cerebral Artery Aneurysms: A Multicenter Retrospective Review

Current state of endovascular treatment of anterior cerebral artery aneurysms

The locations of anterior cerebral artery (ACA) aneurysms vary, and various aneurysms can occur along the course of the ACA. Ruptured and some unruptured ACA aneurysms may require aggressive treatment to avoid bleeding or rebleeding. Although open surgery is an effective treatment for ACA aneurysms, endovascular treatment (EVT) is becoming an alternative treatment in select cases. EVT techniques for ACA aneurysms often vary and are performed on a case-by-case basis according to the nature and location of the aneurysm. To better understand the EVT strategy for ACA aneurysms, it is necessary to review EVT for ACA aneurysms. In this review, the following topics are discussed: ACA anatomy and anomalies, classifications of ACA aneurysms, the natural history of ACA aneurysms, open surgery and EVT statuses for ACA aneurysms, EVT techniques for various ACA aneurysms, and the prognosis and complications of EVT for ACA aneurysms. According to our review and experience, traditional coiling EVT is still the preferred therapy for most ACA aneurysms. For A1 aneurysms, EVT is challenging. After the selection of appropriate cases, deployment of a flow diverter and Woven EndoBridge device can result in a good prognosis for patients with ACA aneurysms. In addition, parent artery occlusion can be used to treat A1 aneurysms with good collateral circulation and some distal ACA aneurysms. In general, EVT is gaining popularity as an alternative treatment option for ACA aneurysms.

The Safety and Efficacy of Leo Stents with Coiling or Alone for Anterior Cerebral Artery Aneurysms

INTRODUCTION

Treatment of anterior cerebral artery (ACA) aneurysms is still not well established. The Leo stent with blood flow direction is a retrievable stent for intracranial aneurysms, whereas it needs to be studied clearly in patients with ACA aneurysms.

METHODS

Consecutive patients with ACA aneurysms were retrospectively enrolled in three neurosurgical centers between January 2016 and October 2021. The data on demographics, aneurysm characteristics, symptom resolution, and postoperative course were collected and analyzed. The aneurysm occlusion status was appraised by Raymond-Ray Occlusion Class (RROC).

RESULTS

A total of 57 patients with ACA aneurysms were included in our study. Immediate postprocedural angiograms showed that 20 aneurysms (35.1%) were in complete occlusion (RROC 1), 26 aneurysms (45.6%) were in near-complete occlusion (RROC 2), 11 aneurysms (19.3%) were in incomplete occlusion (RROC 3). The angiographic follow-up found that the rate of complete occlusion increased to 57.9%, and near-completion and incomplete occlusion dropped to 29.8% and 12.3%, respectively. The angiographic result of the last follow-up improved significantly (Z=- 2.805, P=0.005). Univariate analysis indicated that distal location of aneurysms (Z=4.538, P=0.033) and ruptured aneurysms (χ2=.6120, P=0.032) were potential risk factors for intra-parent artery narrowing. Furthermore, multivariate logistic regression analysis found that A3 aneurysms (95% CI 1.427~32.744, P=0.016) are the key risk factor for intra-parent artery narrowing.

CONCLUSIONS

The Leo stent is safe and effective for aneurysms located in ACA circulations. The overall occlusion degree improved during follow-up. A distal, small artery was the risk factor for intra-parent artery narrowing.

Factors Affecting the Outcome after Surgical Clipping of Ruptured Distal Anterior Cerebral Artery (DACA) Aneurysms

Objective  The purpose of this study is to assess demographic, clinical, and unique morphological characteristics of distal anterior cerebral artery (DACA) aneurysm. The relation of outcome included Glasgow Outcome Scale (GOS) using various independent variables, Hunt and Hess clinical grade (H&H), Miller Fischer grade, intraoperative rupture, and comparison of outcomes at discharge and last follow-up. Methods  Demographic data, aneurysm characteristics, and treatment outcomes were evaluated in 28 ruptured DACA aneurysms operated over a period of 13 years. Association between independent variables and dependent variables (GOS) at discharge and at last follow-up (13 years) was analyzed, and the interrelationship between these factors and outcome was evaluated. GOS was used to assess functional outcomes. Results  Over a period of 13 years, 500 patients harboring ruptured intracranial aneurysms were surgically clipped, and out of them 28 patients (5.6%) had ruptured DACA aneurysms. In this series, 20 (71.4%) patients had low grade and 8 (28.6%) had high grade H&H. Out of the 28 patients, 19 (67.8%) had good recovery, 6 (21.5%) were severely disabled, and 3 (10.7%) died at the time of discharge. On the last follow-up (13 years), smoking ( p -value 0.03) and use of temporary clip ( p -value 0.00) were significant predictors for unfavorable outcome. Conclusion  The results of our case series show that even with ruptured aneurysm excellent overall outcome after microsurgical clipping can be achieved, even though among cerebral aneurysms, DACA aneurysm is considered to have less favorable outcome. Alcohol consumption and use of temporary clip were the predictors for unfavorable outcome at the time of discharge. On the last follow-up, smoking and use of temporary clip were found to be the risk factors for unfavorable outcome. Although the small sample size of this study is a limitation, smoking and use of temporary clip play an important role on the overall outcome. The aim of this study was to analyze data to determine factors which may influence outcome after surgical clipping of ruptured DACA aneurysms.

Mini anterior interhemispheric approach for A3 segment distal anterior cerebral artery aneurysms

INTRODUCTION

Aneurysms of the A3 segment of the distal anterior cerebral artery (DACA), in relation to the genu of the corpus callosum, are specific sub-group which pose unique surgical challenges due to their discrete anatomical location. We describe a mini-anterior interhemispheric approach which can be safely utilised to clip these aneurysms rather than the traditional bifrontal approach.

METHODS

Retrospective analysis of the clinical and radiological data of ruptured DACA-A3 aneurysms operated between 2014 and 2021 at our institute. A curvilinear scalp incision within the hairline followed by raising small, unilateral, free frontal bone flap, avoiding the opening of frontal sinus. Superior sagittal sinus is displaced medially, inter-hemispheric dissection carried out with posterior trajectory and small callosotomy is performed. DACA is skeletonised, proximal control is established, and the A3 aneurysm is dissected and clipped.

RESULT

Our cohort of 18 patients had a definite female preponderance (F:M::2:1) with mean age of 55.6 years. On admission three patients were categorized as WFNS Grade I, thirteen in Grade II, and two in Grade III for subarachnoid haemorrhage. All the patients had evidence of blood in the interhemispheric fissure; intraparenchymal haemorrhage was seen in seven, with intraventricular haemorrhage in six patients. Within the A3 segment six aneurysms were infragenu (inferior), eight were at the genu (anterior) and four were supragenu (superior). Two (11.1%) elderly patients succumbed post-surgery following ischemic infarcts and associated complications. At the time of follow-up at 3 months of the remaining sixteen (72.2%) patients, thirteen had a good outcome (mRS 0-3) and three (16.7%) had a poor outcome (mRS > 3).

CONCLUSION

The mini anterior interhemispheric is an effective minimally invasive alternative for A3 segments aneurysms and helps to avoid the complications of the conventional bifrontal interhemispheric approach.