Association of Perforator Infarction with Clinical Courses and Outcomes Following Surgical Clipping of Ruptured Anterior Communicating Artery Aneurysms

A Right-Sided Approach to Anterior Communicating Artery Aneurysms: A Case Review and Technical Report

Anterior communicating artery (ACoA) aneurysms are the most frequently encountered type of intracranial aneurysm. ACoA aneurysms may require treatment depending on clinical presentation, size, risk of rupture, and ruptured status. In patients where treatment is indicated, options entail endovascular securement or clipping. Under the clipping umbrella, surgical approaches traditionally entail a pterional craniotomy and its modifications such as the lateral supraorbital approach. Sidedness of this craniotomy has been a topic of debate. To discuss this we present a case and technical report with nuances of the approach wherein a 48-year-old female presented with the worst headache of her life. The patient was found to have a ruptured wide-necked 7.2 x 8.1 x 5.8 mm ACoA aneurysm more eccentric to the left and fed from the left A1 intertwined with a frontopolar branch, numerous perforators and the recurrent artery of Heubner. The patient underwent a successful clipping from a right-sided approach. As such, with appropriate skull base drilling, exposure, optimization of brain relaxation, and a generous opening of the Sylvian fissure bilateral internal carotid arteries, anterior cerebral arteries with both A1 and A2 segments, middle cerebral arteries, the ACoA, and the relevant anatomy can be appropriately visualized from a right-sided approach. Therefore, an approach is described to optimize exposure to allow for nearly all anterior communicating aneurysms to be clipped from a right-sided pterional approach.

Ruptured Anterior Communicating Artery Aneurysms Concomitant with Small Intracranial Hematoma: Evacuating Hematoma or Not?

Objective

To identify whether intracranial hematoma (ICH) evacuation improves the prognosis of patients with ruptured anterior communicating artery (AcomA) aneurysms concomitant with small ICHs (≥10 mL and <25 mL).

Methods

Data on patients diagnosed with small ICHs secondary to ruptured AcomA aneurysms who underwent surgery in our department between January 2010 and February 2018 was retrospectively analyzed. The patients were divided into two groups based on whether the hematoma was evacuated. The modified Rankin Scale (mRS) was used to assess prognosis six months after onset.

Results

The study recruited 58 patients, 19 of whom underwent aneurysm clipping and ICH evacuation. While 33 patients underwent aneurysm clipping, 6 patients underwent coiling embolism without ICH evacuation. The average ICH volume was 15.27±4.07 mL. In the hematoma-evacuated group, 13 (68.4%) patients had unfavorable outcomes (mRS scores of 4 to 6). In the non-evacuated hematoma group, 13 (33.3%) patients had unfavorable outcomes (P = 0.001), postoperative infarction occurred in 11 (57.9%) patients in the hematoma evacuation group and 9 (23.1%) patients in the other group (P = 0.009).

Conclusion

ICH evacuation was associated with unfavorable outcomes and postoperative infarction in ruptured AcomA aneurysms with concomitant small hematomas (<25 mL). Aneurysm clipping or coiling without ICH evacuation may be a safe and effective choice; however, further investigation is needed.

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.

Deep Cerebral Perforators: Anatomical Distribution and Clinical Symptoms: An Overview

The anatomic distribution of the deep cerebral perforators is considered either a given or subject to enormous variability. Most published overviews on this topic only report findings from a limited number of anatomic dissections, and no attempt has been made to date to provide a comprehensive overview of all published data. A comprehensive literature search was performed on MEDLINE, Embase, and Google Scholar with the help of an information specialist. Three types of studies were included: (1) articles that described the anatomy and distribution territories of perforator groups arising from the arteries of the circle of Willis; (2) studies that evaluated the anatomy of the deep cerebral perforators using imaging techniques; and (3) studies that evaluated either microsurgically or radiologically confirmed perforator occlusion and reported the (magnetic resonance imaging-confirmed) distribution territory of the infarction together with a description of the clinical symptoms associated as a result of the infarction. A total of 2715 articles were screened and 53 were included. Of these, 40 dealt with the anatomic and imaging anatomy of perforator groups (37 reported results of dissections and 3 results of imaging studies), with a total of 2421 hemispheres investigated. Another 13 articles with 680 patients were included that evaluated perforator infarction territories. The deep cerebral perforator distribution shows large variability with poor concordance rates among reported studies, with the exception of the posterior communicating and anterior choroidal artery perforators. Despite the assumption that cerebral perforator anatomy is a given, studies show large variability in the anatomic distribution of various perforator groups. Perforator anatomy and relationships between perforator groups, as well as potential collateral circulation in these territories should be prioritized as a research topic in cerebrovascular disease in the near future.

Tailored Communicating Bypass for the Management of Complex Anterior Communicating Artery Aneurysms: "Flow-Counteraction" In Situ Bypass and Interposition Bypass Using Contralateral A2 Orifice as Donor Site

BACKGROUND

The use of bypass surgery for anterior communicating artery (ACOM) aneurysms is technically challenging. Communicating bypass (COMB), such as pericallosal artery side-to-side anastomosis, is the most frequently used and anatomically directed reconstruction option. However, in many complex cases, this technique may not afford a sufficient blood supply or necessitate sacrificing the ACOM and the eloquent perforators arising from it.

OBJECTIVE

To evaluate tailored COMB and propose a practical algorithm for the management of complex ACOM aneurysms.

METHODS

For 1 patient with an aneurysm incorporating the entire ACOM, conventional in Situ A3-A3 bypass was performed as the sole treatment in order to create competing flow for aneurysm obliteration, sparing the sacrifice of eloquent perforators. In situations in which A2s were asymmetric in the other case, the contralateral A2 orifice was selected as the donor site to provide adequate blood flow by employing a short segment of the interposition graft.

RESULTS

The aneurysm was not visualized in patients with in Situ A3-A3 bypass because of the "flow-counteraction" strategy. The second patient, who underwent implementation of the contralateral A2 orifice for ipsilateral A3 interposition bypass, demonstrated sufficient bypass patency and complete obliteration of the aneurysm.

CONCLUSION

The feasibility of conventional COMB combined with complete trapping may only be constrained to selected ideal cases for the treatment of complex ACOM aneurysms. Innovative modifications should be designed in order to create individualized strategies for each patient because of the complexity of hemodynamics and the vascular architecture. Flow-counteraction in Situ bypass and interposition bypass using the contralateral A2 orifice as the donor site are 2 novel modalities for optimizing the advantages and broadening the applications of COMB for the treatment of complex ACOM aneurysms.

Application of the Endoscopic Micro-Inspection Tool QEVO® in the Surgical Treatment of Anterior Circulation Aneurysms-A Technical Note and Case Series

Introduction: The application of neuro-endoscopes in cerebral aneurysm surgery may help to avoid unintended aneurysm remnants and the accidental clipping of perforating arteries and aid the detection of blood collecting in the subdural spaces. Here, we present our experience with the novel endoscopic micro-inspection tool QEVO® (Carl Zeiss Meditec, Germany) in aneurysm surgery.

Materials and Equipment: In all patients the surgical microscope KINEVO® (Carl Zeiss Meditec, Germany) and the Microinspection tool QEVO® were applied.

Methods: The case series comprises 22 unruptured cerebral aneurysms of the anterior circulation. All aneurysms were treated surgically. All patients routinely underwent computed tomography and digital subtraction angiography within 10 days after surgery.

Results: No aneurysm remnants, cerebral ischemic deficits, or subdural hematomas were detected.

Discussion: In this technical note, we discuss the benefits and limitations of the QEVO® tool and illustrate the major paradigms by means of intraoperative photographs.

Anterior Communicating Artery Aneurysms: Anatomical Considerations and Microsurgical Strategies

Anterior communicating artery aneurysms account for 23–40% of ruptured intracranial aneurysms and 12–15% of unruptured aneurysms and are the most common intracranial ruptured or unruptured aneurysms. Because they have relatively complex anatomical structures and anatomical variations and are adjacent to important blood vessels and structures, in the process of microsurgical exposure of an Anterior communicating artery aneurysm, attention should be paid not only to the anatomical characteristics of the aneurysm itself but also to the adjacent important blood vessels and perforating arteries; therefore, both surgical clipping and endovascular embolization are serious challenges for neurosurgeons. No matter which treatment is chosen, it is necessary to determine the structure of the Anterior communicating artery and its perforating arteries as well as whether there is a fenestration deformity of the Anterior communicating artery and the relationship between bilateral A1-A2 before surgery. The shape and size of the aneurysm itself and its location relative to adjacent blood vessels also need to be considered to better complete the procedure, and this is especially true for microsurgical clipping. Clarifying the anatomy before surgery is helpful for better selecting the surgical approach and surgical side, which could affect the intraoperative exposure of the aneurysm and adjacent arteries, the surgical difficulty, the resection rate, and the postoperative complications. Therefore, starting with Anterior communicating artery aneurysms and their adjacent structures and variations, this paper reviews the latest progress in surgical treatment based on anatomic specificity as well as the most recent clinical studies.

Adverse intraoperative events during surgical repair of ruptured cerebral aneurysms: a systematic review

Compared with endovascular techniques, clipping of ruptured cerebral aneurysms has been shown to associate with increased morbidity in several studies. Despite this, clipping remains the preferred option for many aneurysms. The objective of this study is to describe the reported adverse events of open repair of ruptured cerebral aneurysms and their impact on patient outcome. The PubMed, Embase and Cochrane databases were searched between June 1999 and June 2019 to identify original studies of at least 100 patients undergoing surgical repair of ruptured cerebral aneurysms and in which adverse event rates were reported. Thirty-six studies reporting adverse events in a total of 12,410 operations for repair of ruptured cerebral aneurysms were included. Surgical adverse events were common with 36 event types reported including intraoperative rupture (median rate of 16.6%), arterial injury (median rate of 3.8%) and brain swelling (median rate 5.6%). Only 6 surgical events were statistically shown to associate with poor outcomes by any author and for intraoperative rupture (the most frequently analysed), there was an even split between authors finding a statistical association with poor outcome and those finding no association. Even with modern surgical techniques, the technical demands of surgical aneurysm repair continue to lead to a high rate of intraoperative adverse events. Despite this, it is not known which of these intraoperative events are the most important contributors to the poor outcomes often seen in these patients. More research directed towards identifying the events that most drive operative morbidity has the potential to improve outcomes for these patients.

Safety and efficacy of anterior communicating artery compromise during endovascular coil embolization of adjoining aneurysms

OBJECTIVE

In the presence of symmetric A1 flow, the safety and efficacy of compromising the anterior communicating artery (ACoA) during coil embolization of ACoA aneurysms has yet to be evaluated. Herein, the authors describe their experience, focusing on procedural safety.

METHODS

Between October 2012 and July 2017, 285 ACoA aneurysms with symmetric A1 flows were treated at the authors' institution by endovascular coil embolization. Clinical and angiographic outcome data were subjected to binary logistic regression analysis.

RESULTS

ACoA compromise was chosen in the treatment of 71 aneurysms (24.9%), which were completely (n = 15) or incompletely (n = 56) compromised. In the remaining 214 lesions, the ACoA was preserved. Although 9 patients (3.2%) experienced procedure-related thromboembolisms (compromised, 4; preserved, 5), all but 1 patient (with ACoA compromise) were asymptomatic. In multivariate analysis, subarachnoid hemorrhage at presentation was the sole independent risk factor for thromboembolism (OR 15.98, p < 0.01), with ACoA compromise being statistically unrelated. In 276 aneurysms (96.8%) with follow-up of > 6 months (mean 20.9 ± 13.1 months, range 6-54 months), recanalization was confirmed in 21 (minor, 15; major, 6). A narrow (≤ 4 mm) saccular neck (p < 0.01) and ACoA compromise (p = 0.04) were independently linked to prevention of recanalization.

CONCLUSIONS

During coil embolization of ACoA aneurysms, the ACoA may be compromised without serious complications if A1 flows are symmetric. This approach may also confer some long-term protection from recanalization, serving as a valid treatment option for such lesions.