Endovascular treatment of unruptured A1 segment aneurysms

Endovascular management of saccular aneurysms of the proximal A1 segment: technical particularities and long term outcomes

BACKGROUND

Saccular aneurysms of the proximal A1 segment (SAPA1) are rare, but their treatment is challenging and scarcely described in the literature. We report the immediate and long term outcomes of their endovascular management.

METHODS

We retrospectively analyzed all consecutive SAPA1 cases treated endovascularly at our center between 2003 and 2023. Per procedural complications and radioclinical outcomes were prospectively recorded.

RESULTS

Among 2468 patients followed up for aneurysms, 12 (0.49%) had an SAPA1 (average age 53.8±9.6 years, 9 women). The SAPA1 averaged 3.3 mm, all posteriorly oriented. Ten were ruptured (83.3%). Initial treatments included conventional coiling or balloon assisted coiling (CC/BAC) for nine aneurysms, and proximal A1 segment focal occlusion (PA1FO) for three. Initial occlusion was deemed satisfactory in all instances: total occlusion in eight cases (67%) and subtotal occlusion in four cases (33%). Four aneurysmal perforations occurred (33%), all during CC/BAC on ruptured aneurysms. Over a 10.2 year average follow-up, six recanalizations (50%) were noted, all after initial CC/BAC: three were early (≤14 days), with one causing fatal rebleeding. No recanalizations after PA1FO was observed (five in total, two as a complement after CC/BAC). Favorable clinical outcomes (modified Rankin Scale score of 0-2) were seen in 91% of cases (11/12) at the last follow-up.

CONCLUSIONS

Selective coiling of the aneurysmal sac is technically difficult due to their small size and the complex microcatheterization pathway. This method presents a significant risk of aneurysmal perforation, especially in ruptured cases, and a high rate of recanalization. PA1FO, when collateralization permits, appears to be a reliable therapeutic alternative offering favorable long term outcomes.

Surgery Versus Endovascular Treatment for Proximal Anterior Cerebral Artery Aneurysms: A Meta-Analysis

BACKGROUND

Proximal anterior cerebral artery (PACA) aneurysms account for less than 1% of all intracranial aneurysms. These aneurysms possess a challenge to surgeons due to their small size, wide base, fragile wall, and accompanying vascular anomalies. Surgery and endovascular treatment are both effective treatment options for PACA aneurysms but there is currently no consensus on which is the method of choice.

OBJECTIVE

A systematic review and meta-analysis was conducted to investigate treatment strategies for aneurysms at proximal anterior cerebral artery.

MATERIAL AND METHODS

The Cochrane Library, EMBASE, PubMed, and Web of Science databases were systematically searched for studies published between January 01, 2000 and December 01, 2020 that investigated surgery and/or endovascular treatment for patients with PACA.

RESULTS AND CONCLUSIONS

Nineteen retrospective studies involving 358 patients met the inclusion criteria. Among these patients, 150 were treated surgically and 208 were treated using an endovascular technique. Preoperative morbidity was significantly greater in the surgical patients compared with the endovascular treated patients but there was no difference between groups in procedural related morbidity. The rates of favorable clinical outcome at time of discharge and at follow-up were statistically significantly greater in the endovascular group compared with the surgical group. Procedural related mortality was 8.7% for the surgical group and 1% in the endovascular group. In summary, our meta-analysis emphasized the safety and efficiency of endovascular treatment, and concluded that it was superior to surgery in acquiring favorable clinical outcome and reducing the perioperative complications. However, surgery was still the preferred treatment strategy for ruptured PACA aneurysms. Preoperative evaluation seems to be of great vital.

Navigating complexity: a comprehensive review of microcatheter shaping techniques in endovascular aneurysm embolization

The endovascular intervention technique has gained prominence in the treatment of intracranial aneurysms due to its minimal invasiveness and shorter recovery time. A critical step of the intervention is the shaping of the microcatheter, which ensures its accurate placement and stability within the aneurysm sac. This is vital for enhancing coil placement and minimizing the risk of catheter kickback during the coiling process. Currently, microcatheter shaping is primarily reliant on the operator's experience, who shapes them based on the curvature of the target vessel and aneurysm location, utilizing 3D rotational angiography or CT angiography. Some researchers have documented their experiences with conventional shaping methods. Additionally, some scholars have explored auxiliary techniques such as 3D printing and computer simulations to facilitate microcatheter shaping. However, the shaping of microcatheters can still pose challenges, especially in cases with complex anatomical structures or very small aneurysms, and even experienced operators may encounter difficulties, and there has been a lack of a holistic summary of microcatheter shaping techniques in the literature. In this article, we present a review of the literature from 1994 to 2023 on microcatheter shaping techniques in endovascular aneurysm embolization. Our review aims to present a thorough overview of the various experiences and techniques shared by researchers over the last 3 decades, provides an analysis of shaping methods, and serves as an invaluable resource for both novice and experienced practitioners, highlighting the significance of understanding and mastering this technique for successful endovascular intervention in intracranial aneurysms.

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.

Microcatheter Re-Shaping Using Fusion Image in Coil Embolization: A Technical Note

Objective

We report the utility of microcatheter reshaping by referring to fusion images with 3D-DSA and microcatheter 3D images made using non-subtraction and non-contrast (non-SC) rotational images.

Case Presentations

Case 1: The patient was a 74-year-old man who had an internal carotid-anterior choroidal artery bifurcation aneurysm with a tortuous proximal parent artery. The initial attempt to introduce the microcatheter into the aneurysm was unsuccessful. During this unsuccessful microcatheter introduction, we created fusion images with 3D-DSA and microcatheter 3D images by acquiring positional information of the microcatheter using the non-SC method. By reshaping the microcatheter with reference to the fusion images, the direction of the distal end of the microcatheter was reshaped to be in accordance with the long axis of the aneurysm, a shape more suitable for coiling. Case 2: The patient was a 47-year-old man who had an anterior communicating (A-com) artery aneurysm with two daughter sacs. We successfully placed two microcatheters in the direction of each sac to make more stable framing by referring to 3D fusion images after the first microcatheter was positioned. In both cases, microcatheter reshaping was necessary because of the vessel and aneurysm anatomy. We have used this technique successfully in 15 patients, for both ruptured and unruptured aneurysms. The average number of microcatheter reshaping was 1.3 times.

Conclusion

This method provides effective microcatheter reshaping for coil embolization of aneurysms, particularly those with differences between the axis of the parent artery and the vertical axis of aneurysm, or with a tortuous proximal artery.

Endovascular treatment for aneurysms at the A1 segment of the anterior cerebral artery: current difficulties and solutions

Aneurysms located at the A1 segment of the anterior cerebral artery are considered rare and unique entities. Endovascular treatment (EVT) is effective in preventing aneurysmal bleeding. However, EVT for A1 aneurysms is difficult due to their distinctive configurations. A current review of EVT for A1 aneurysms is lacking. Therefore, we focused on the available literature on this specific issue. To more clearly expound this entity, we also provided some illustrative cases. The A1 segment can be equally divided into the proximal, middle, and distal segments. Proximal aneurysms are most common and difficult to treat via EVT. The A1 segment has a complex anatomy and many important branches. Due to the small size, predominant posterior direction, and sharp upturn of the microcatheter from the parent artery, microcatheter positioning and support is difficult for A1 aneurysms. EVT for A1 aneurysms mainly includes reconstructive and deconstructive strategies. The complications of EVT for A1 aneurysms include aneurysmal perforation, thromboembolic events, and coil protrusion related to stent-assisted embolization. A1 aneurysms represent rare and difficult vascular lesions. EVT is quite challenging for A1 aneurysms due to their distinctive configurations. The outcomes are acceptable.

Management of Proximal Segment of the Anterior Cerebral Artery Aneurysms

ABSTRACT

The authors reported 2 cases with proximal anterior cerebral artery (A1) aneurysms, and one was treated with aneurysm clipping, whereas another was treated with coil embolization. The authors suggest both endovascular surgery and aneurysm clipping are good options for A1 aneurysms.

Microcatheter shaping using three-dimensional printed models for intracranial aneurysm coiling

Background and purpose

Microcatheterization is an important, but also difficult, technique used for the embolization of intracranial aneurysms. The purpose of this study was to investigate the application of three-dimensional (3D) printing technology in microcatheter shaping.

Methods

Nine cases of internal carotid artery posterior communicating artery aneurysm diagnosed by CT angiography were selected, and 3D printing technology was used to build a 3D model including the aneurysm and the parent artery. The hollow and translucent model had certain flexibility; it was immersed in water and the microcatheter was introduced into the water to the target position in the aneurysm, followed by heating the water temperature to 50°C. After soaking for 5 min, the microcatheter was taken out and the shaping was completed. After sterilization, the shaped microcatheter was used for arterial aneurysm embolization and evaluation was conducted.

Results

Nine cases of microcatheter shaping were satisfactory and shaping the needle was not necessary; no rebound was observed. The microcatheter was placed in an ideal position, and the stent-assisted method was used in three cases of wide-neck aneurysm. There were no complications related to surgery.

Conclusion

A new microcatheter shaping method using 3D printing technology makes intracranial artery aneurysm embolization more stable and efficient.

The Special Considerations in the Surgical Management of Proximal Anterior Cerebral Artery Aneurysms

BACKGROUND

Proximal anterior cerebral artery (A1) aneurysms are difficult to clip because of their frequent proximity to perforators, location behind the parent artery, or adherence to surrounding structures.

METHODS

We retrospectively reviewed a consecutive series of patients with A1 aneurysms and report the clinical status, radiologic findings, treatment methods, and outcome.

RESULTS

This series included 19 male and 12 female patients with a mean age of 50 years. The morphology of the A1 aneurysms was fusiform in 2 patients and saccular in the remaining 29 patients. Multiple aneurysms were presented in 9 patients (29.0%). On admission, 26 patients (83.9%) presented with subarachnoid hemorrhage, 3 of whom had an additional intracerebral hematoma. All surgeries were performed with a standard pteriomal craniotomy. The mean Glasgow Outcome Scale score at final follow-up was 4.8 (interquartile range, 5, 5), with 26 patients (83.9%) rated as 5. The mean follow-up time was 38.5 months (range, 12-60 months).

CONCLUSIONS

A1 aneurysms are rare but have their own complex characteristics and are difficult to treat. Meticulous analysis of the relevant angiographs is needed for their diagnosis. An important consideration in surgery is the preservation of perforators and prevention of rupture. Wide opening of the sylvian fissure and temporary control of the parent artery can facilitate dissection of the A1 aneurysms dome. Multiple intraoperative monitoring methods, such as microvascular Doppler ultrasonography and somatosensory and motor evoked potential monitoring, can reduce the relevant complications of surgery.

Angiographic Characteristics and Endovascular Treatment of Anterior Cerebral Artery A1 Segment Aneurysms

OBJECTIVE

This report aimed to review the angiographic characteristics and evaluate the safety and feasibility of endovascular treatment of A1 aneurysms.

METHODS

Nineteen ruptured and 13 unruptured A1 aneurysms treated endovascularly were evaluated in this study. The angiographic and clinical records were retrospectively reviewed.

RESULTS

Endovascular treatments were successfully applied in all 32 aneurysms. Conventional coiling was performed in 24 aneurysms, stent-assisted coiling in 7, and solo stenting in 1. The immediate angiographic result was 1 aneurysm in 15, two aneurysms in 10, and 3 in 7 aneurysms according to the Raymond grade. Intraoperative rupture was detected in 1 case without clinical consequence, and no other procedure-related complication occurred. Angiographic follow-up (mean, 12 months; range, 2-42 months) of 25 aneurysms showed total occlusion in 20, improvement in 1, stability in 3, and recurrence in 1. The only recurrence was detected in a case treated using conventional coiling, and it was retreated with stent-assisted coiling. Clinical follow-up (mean, 25 months; range, 6-93 months) was available in 24 of 30 patients, and the modified Rankin Scale score was 0-1 in 22 patients.

CONCLUSIONS

Endovascular treatment is technically feasible and safe for A1 aneurysms.