Large distal anterior cerebral artery aneurysm treated with resection and interposition graft: case report

Angiographic and Clinical Outcomes of Various Techniques of Intracranial-to-Intracranial Bypass for Complex Cases with a Review of Pertinent Literature and Illustrated Cases

BACKGROUND

We sought to determine the utility of intracranial-to-intracranial bypass (IIB) surgery and the available bypass options for complex cases.

METHODS

A total of 18 IIB cases were included. Each case was classified as IIB with or without an interposition graft. The clinical and angiographic status were evaluated pre- and postoperatively and at the last follow-up. Angiographic images were analyzed and reconstructed schematically. Postoperative angiography was used to measure the bypass patency and the presence of postoperative cerebral infarction. The recipient artery occlusion time for each bypass was measured.

RESULTS

Of the 18 patients, 14 had presented with a complex intracranial aneurysm (IA), 1 with vertebrobasilar dolichoectasia, and 3 with intracranial arterial steno-occlusive disease. Ten patients had an incidentally discovered IA. Seven patients had presented with neurological deficits due to ischemia or aneurysmal mass effects. Of the 18 cases, 10 were IIBs with an interposition graft, including 4 cases of superficial temporal artery and 6 of radial artery graft bypass, and 8 were IIBs with a noninterposition graft, including 3 cases of in situ bypass, 1 case of reanastomosis, and 4 cases of reimplantation. The pre- and postoperative modified Rankin scale score did not change or improve, and all the bypasses were patent. No patient had died during the mean follow-up period of 50.0 months. The mean occlusion time of the recipient artery was 59.5 minutes. A total of 8 patients experienced postoperative cerebral infarction but all had almost recovered at discharge.

CONCLUSIONS

With proper selection of the IIB type, IIB can be a suitable treatment option for some patients with complex IAs and intracranial arterial steno-occlusive disease when extracranial-to-intracranial bypass is not feasible.

Fusiform aneurysms of anterior cerebral artery: center experience and systematic literature review

Fusiform aneurysms of the anterior cerebral artery (ACA) are uncommon, and the natural history of this entity is poorly characterized. Along with our center experience, we conducted a systematic literature review to help shed light on the clinical course of ACA fusiform aneurysms. We queried our institutional database to identify cases with fusiform aneurysms of ACA. In addition, following the PRISMA algorithm, we identified all reported cases published in the English literature from the inception of PubMed until December 2022. We categorized clinical presentations into three categories: (i) traumatic/iatrogenic, (ii) spontaneous symptomatic ruptured/unruptured, and (iii) spontaneous asymptomatic aneurysms. We utilized descriptive statistics. We identified seven cases from our center along with 235 patients from published literature. Blunt trauma was responsible for the development of 19 aneurysms. Sixty-three percent of these aneurysms tend to rupture within 2 weeks from the initial trauma, and despite treatment, only 74% of these patients had good clinical outcomes. Spontaneous symptomatic presentation occurred in 207 patients and was often associated with previous/concomitant ACA dissection. Subarachnoid hemorrhage from ruptured aneurysms was the most common presentation. Spontaneous symptomatic fusiform aneurysm is rapidly evolving lesions, and treatment is necessary. Three of our own cases were treated with an endovascular flow diverter (pipeline) stenting with good outcomes. Spontaneous asymptomatic aneurysms were reported in nine patients. These lesions are often associated with other vascular abnormalities. Treatment included surgical clipping with good clinical outcomes. Instead, four patients from our center database were managed conservatively with equally good outcomes. Our study demonstrates good clinical outcomes when fusiform aneurysms of ACA, especially when symptomatic, are treated promptly with either reconstructive or deconstructive therapies.

Superficial temporal artery interposition bypass for the treatment of complex intracranial aneurysms: Flexible and creative options for flow preservation bypass

PURPOSE

Flow-preservation bypass is a treatment option for complex intracranial aneurysms (IAs) that cannot be managed with microsurgical clipping or endovascular treatment. Various bypass methods are available, including interposition grafts such as the radial artery or saphenous vein. Size discrepancy, invasiveness, and procedure complexity must be considered when using interposition grafts. We describe our experience of treating complex IAs using a superficial temporal artery (STA) interposition bypass.

METHODS

We retrospectively reviewed the medical records and operative videos of all patients who were treated for complex IAs at our center from January 2009 to December 2021 using cerebral revascularization. Clinical, radiological, and surgical findings of the cases that underwent STA interposition bypass were investigated.

RESULTS

Seventy-six bypass procedures were performed of which seven (9.2%) complex IAs were managed using STA interposition bypass. Of these 5 cases were of anterior cerebral artery, 1 of middle cerebral artery, and 1 of posterior inferior cerebellar artery aneurysm. There were no postoperative ischemic complications. Revision surgery for postoperative pseudomeningocele was performed in one case. The long-term bypass patency rate was 85.7% (6 out of 7) and good long-term aneurysm control was achieved in all cases, with a mean follow-up of 64 months.

CONCLUSIONS

When treating complex IAs, creative revascularization strategies are needed in selective cases for favorable outcomes. STA interposition graft bypass which can reduce the size discrepancy between the donor and recipient may be a less invasive, flexible, and practical option for treating complex IAs.

Single institute experience of bypass surgery for complex anterior cerebral artery aneurysms: paying special attention to the spatial and diameter relationship between the efferent arteries

Single institute experience with bypass surgery of complex ACA aneurysm was retrospectively reviewed over a 6-year period. Eight patients with complex ACA aneurysms were treated with bypass, including five females and three males, with mean age of 34.2 years old. There were three pre-communicating aneurysms, one communicating artery aneurysm, and four post-communicating aneurysms (two in A2 and two in A3). A3-A3 side-to-side in situ bypass was applied in six cases. A3-radial artery-A3 interpositional bypass was used in one case with far apart A3s, and A3-A3 transplantation in the other with unparalleled aligned A3s. Three aneurysms were secured with proximal clipping, one with distal clipping, one with direct clipping, one with isolation, and two with embolization. Aneurysm obliteration was achieved in all cases. Only one in situ bypass from smaller donor artery towards larger recipient artery failed with minor postoperative infarction. Intraoperative bleeding from the site of anastomosis occurred in one case during embolization. All the patients showed complete recovery with normal neurological function during follow-up at out-of-patient clinics. A simplified surgical algorithm for complex ACA aneurysm is established based on the geometrical and spatial relationship between efferent arteries. The reasons of bypass failure and hemorrhagic complication are also discussed.

In Situ Side-to-Side Pericallosal-Pericallosal Artery and Callosomarginal-Callosomarginal Artery Bypasses for Complex Distal Anterior Cerebral Artery Aneurysms: A Technical Note

BACKGROUND

Despite surgical and endovascular technical improvements over the last decades, the treatment of complex aneurysms of the distal anterior cerebral artery (ACA) is very challenging for both vascular neurosurgeons and interventional neuroradiologists. Furthermore, the interpersonal anatomic variability requires, most of the time, a tailored planning.

OBJECTIVE

To describe a novel technique of bypasses in the territory of ACA to protect the brain territory distal to the aneurysm.

METHODS

A 53-yr-old male with a large complex fusiform aneurysm of the left distal A2 segment of the ACA, involving the origin of the callosomarginal and pericallosal arteries, was judged not suitable for a single procedure (endovascular or neurosurgical). Two side-to-side bypasses were performed in a single surgery to connect the pericallosal and callosomarginal arteries of both sides, distally to the aneurysm. Subsequently, an endovascular embolization of the aneurysm was achieved with coils.

RESULTS

The patency of the microanastomoses, performed in the anterior interhemispheric fissure, was positively evaluated intraoperatively with indocyanine green and fluorescein videoangiography. The aneurysm sac, together with proximal A2 segment, was completely occluded with platinum coils. At the last follow-up, computed tomography angiography confirmed the patency of both bypasses, without any sign of aneurysm recanalization. The patients never complained of any focal neurological deficits or worsening of clinical status.

CONCLUSION

We present an elegant and innovative solution to completely protect the distal ACA territory in cases of complex aneurysm involving the origin of both callosomarginal and pericallosal arteries.

"Fountain Sign," a Basic Finding toward the Diagnosis of Partially Thrombosed Giant Aneurysm: Describing a Challenging Case and Literature Review

Although the occurrence of cerebral aneurysms in pediatric age group describes as rare, giant ones are more commonly be found than in adults. Insufficient epidemiological information, their association with other medical comorbidities, diagnostic pitfalls, complex surgical anatomy, and issues should be considered during surgery to make them difficult to diagnose and manage. We report a 6-year-old boy with presenting complaint of acute-onset headache without any other symptoms and a small area of intracerebral hemorrhage detected on initial computed tomography (CT) scan. Primary evaluations failed to result in a definite diagnosis, and delayed vascular studies suggested vascular malformation or an aneurysm as the causative factor of hemorrhage. Surgical exploration led to the diagnosis of a giant partially thrombosed aneurysm at the A2 segment of the left anterior cerebral artery and successful clipping. One of our findings on preoperative CT angiography, “fountain sign,” may be useful for the diagnosis of partially thrombosed aneurysms when active bleeding from the aneurysm has been ruled out. Fountain sign can be a useful finding in the diagnosis of partially thrombosed aneurysms. Vascular lesions should always be considered as the primary cause of intracranial hemorrhage in pediatrics despite negative initial studies. Therefore, close follow-up and using delayed and multimodality vascular evaluations are crucial for successful management.

Provocative Testing Prior to Anterior Cerebral Artery Fusiform Aneurysm Embolization

We report 2 cases of parent artery occlusion (PAO) for anterior cerebral artery (ACA) fusiform aneurysm embolization after superselective provocative testing was performed to confirm distal territory viability. The first case involves a patient in the second decade of life who presented with subarachnoid hemorrhage and underwent PAO after a balloon test occlusion in the distal ACA revealed no neurophysiology changes. The second case involves another patient in the forth decade of life who presented with an enlarging pseudoaneurysm and underwent PAO after a sodium amobarbital infusion in the distal ACA revealed no clinical change. Both patients tolerated PAO without clinical compromise. PAO after provocative testing may be a safe and effective strategy in the management of fusiform aneurysm treatment.

Key Messages

Provocative testing with superselective balloon test occlusion and sodium amobarbital infusion are both viable options for clinical and physiological interrogation of brain tissue prior to parent vessel occlusion. Neurophysiological monitoring may be a useful surrogate for clinical examination after provocative testing, particularly if patients were treated under general anesthesia.

Operative Management of Distal Anterior Cerebral Artery Aneurysms Through a Mini Anterior Interhemispheric Approach

BACKGROUND

Distal anterior cerebral artery (DACA) aneurysms, also known as pericallosal artery aneurysms, are present in 1.5%-9% of all intracranial aneurysms. Here we characterize the important microsurgical anatomy of DACAs; describe the surgical approach to treating these aneurysms with a minimally invasive surgical technique, the mini anterior interhemispheric approach (MAIA); and examine the nuances of aneurysm clipping in this region.

METHODS

This was a retrospective and descriptive analysis of a series of aneurysm surgeries performed at the National Institute of Neurology and Neurosurgery in Mexico City. Cadaveric dissections were used to demonstrate relevant cerebrovascular anatomy. We analyzed patient demographic data and aneurysm characteristics. Patients' neurologic grade was evaluated using the Hunt and Kosnik (H-K) scale, and surgical outcomes were evaluated using the Glasgow Outcome Scale (GOS). Other variables were analyzed using the χ² test.

RESULTS

We analyzed a total of 32 DACA aneurysms (10 nonruptured and 22 ruptured), representing 5.8% of all aneurysms. The study cohort was 64.3% females and 35.7% males. H-K grade II was the most frequent classification (32.4%); 42.8% of patients presented with a Fisher grade IV aneurysm. Aneurysm location was classified as supra-genu, genu, or infra-genu. Eight patients had multiple aneurysms, among which 50% were located at the bifurcation of the middle cerebral artery.

CONCLUSIONS

Surgical clipping through a MAIA approach is an excellent treatment option for pericallosal artery aneurysms.

Rescue bypass for the treatment of pseudoaneurysm on the distal anterior cerebral artery: a case report of vertical side-to-side anastomosis of the distal callosomarginal artery-pericallosal artery

Pseudoaneurysm on the distal anterior cerebral artery (ACA) is rare but potentially fatal. It usually cannot be treated with typical treatment modalities. A 47-year-old female patient was diagnosed with a ruptured aneurysm on the pericallosal artery (PerA). During surgical exploration, it was found to be a pseudoaneurysm and could not be treated with clipping. We performed surgical trapping of the involved segment of the proximal PerA followed by side-to-side anastomosis between the ipsilateral PerA and the callosomarginal artery. The patient recovered without any neurologic deficit. This new method of anastomosis could be an alternative option.

Single center experience and technical nuances in the treatment of distal anterior cerebral artery aneurysms

Objective: This study presents the experience of one neurosurgical center in the treatment of 18 consecutive patients with distal anterior cerebral artery (DACA) aneurysms during a 10 years period. Our aim was to compare treatment outcomes of these lesions with intracranial aneurysms in general, and to present technical nuances in surgical treatment.

Methods: We analyzed the clinical and radiological data of 18 patients treated between 2005 and 2015. All patients were treated surgically using the microscope. No patients were lost to follow-up. We compared treatment and outcome of ruptured DACA aneurysms (n 18) with all consecutive ruptured aneurysms treated in our clinic during the same period (n 446).

Results: DACA aneurysms accounted for 4% of all intracranial aneurysms. They were smaller (median, 5,5 versus 9 mm) We found only one case with associated aneurysms (5,5%). DACA aneurysms presented more often with intracerebral hematomas (39% versus 26%) than ruptured aneurysms in general. Their microsurgical treatment showed the same complication rates (treatment morbidity, 15%) as for other ruptured aneurysms in literature. Their mortality rate was lower (11% versus 24%).

Conclusion: Despite their specific anatomic features, and particular surgical technique, with modern treatment methods, ruptured DACA aneurysms have the same favorable outcome and lower mortality as ruptured aneurysms in general.

A case of ruptured infectious anterior cerebral artery aneurysm treated by interposition graft bypass using the superficial temporal artery

Background:

To describe the application of an interposition graft bypass using superficial temporal artery (STA) for the treatment of a ruptured anterior cerebral artery (ACA) infectious aneurysm.

Case Description:

A 30-year-old male suffered from severe headache with high fever. The patient's diagnosis was ruptured infectious ACA aneurysm at the A3 segment with a maximum diameter of 4.5 mm, caused by infectious endocarditis. The patient was initially treated with high-dose intravenous antibiotics. Follow-up digital subtraction angiography (DSA) revealed that the fusiform aneurysm had enlarged to a maximum diameter of 14.0 mm. A left paracentral artery, supplying the motor area of the left lower extremity, originated from the body of this aneurysm. Because the angiographic findings suggested a risk of recurrent bleeding, the patient underwent open surgery. Interposition graft bypass using the STA was performed to reconstruct the left A3 segment in an end-to-side manner (left proximal callosomarginal artery – STA graft – left distal pericallosal artery). Then, the origin of the left paracentral artery was cut and anastomosed to the STA graft in an end-to-side manner. The affected parent artery was trapped, and the aneurysm was resected. Postoperative magnetic resonance imaging showed no ischemic or hemorrhagic complications, and postoperative DSA revealed the patency of the interposition graft. Pathological diagnosis of the resected aneurysm revealed features corresponding to infectious cerebral aneurysm. The postoperative course was uneventful, and the patient was discharged without any neurological deficits.

Conclusion:

In the treatment of infectious cerebral aneurysms, revascularization should be considered when the affected artery supplies the eloquent area. Interposition graft bypass using the STA is one of the options for revascularization surgery for the treatment of infectious ACA aneurysms.

Anterior cerebral artery bypass for complex aneurysms: an experience with intracranial-intracranial reconstruction and review of bypass options

Object

The authors describe their experience with intracranial-to-intracranial (IC-IC) bypasses for complex anterior cerebral artery (ACA) aneurysms with giant size, dolichoectatic morphology, or intraluminal thrombus; they determine how others have addressed the limitations of ACA bypass; and they discuss clinical indications and microsurgical technique.

Methods

A consecutive, single-surgeon experience with ACA aneurysms and bypasses over a 16-year period was retrospectively reviewed. Bypasses for ACA aneurysms reported in the literature were also reviewed.

Results

Ten patients had aneurysms that were treated with ACA bypass as part of their surgical intervention. Four patients presented with subarachnoid hemorrhage and 3 patients with mass effect symptoms from giant aneurysms; 1 patient with bacterial endocarditis had a mycotic aneurysm, and 1 patient's meningioma resection was complicated by an iatrogenic pseudoaneurysm. One patient had his aneurysm discovered incidentally. There were 2 precommunicating aneurysms (A1 segment of the ACA), 5 communicating aneurysms (ACoA), and 3 postcommunicating (A2–A3 segments of the ACA). In situ bypasses were used in 4 patients (A3-A3 bypass), interposition bypasses in 4 patients, reimplantation in 1 patient (pericallosal artery-to-callosomarginal artery), and reanastomosis in 1 patient (pericallosal artery). Complete aneurysm obliteration was demonstrated in 8 patients, and bypass patency was demonstrated in 8 patients. One bypass thrombosed, but 4 years later. There were no operative deaths, and permanent neurological morbidity was observed in 2 patients. At last follow-up, 8 patients (80%) were improved or unchanged. In a review of the 29 relevant reports, the A3-A3 in situ bypass was used most commonly, extracranial (EC)–IC interpositional bypasses were the second most common, and reanastomosis and reimplantation were used the least.

Conclusions

Anterior cerebral artery aneurysms requiring bypass are rare and can be revascularized in a variety of ways. Anterior cerebral artery aneurysms, more than any other aneurysms, require a thorough survey of patient-specific anatomy and microsurgical options before deciding on an individualized management strategy. The authors' experience demonstrates a preference for IC-IC reconstruction, but EC-IC bypasses are reported frequently in the literature. The authors conclude that ACA bypass with indirect aneurysm occlusion is a good alternative to direct clip reconstruction for complex ACA aneurysms.

Occlusion of canine aneurysms using microporous self-expanding stent grafts: long-term follow-up

PURPOSE

The treatment of large or giant cerebral aneurysms by surgical and/or endovascular techniques is difficult and poses relatively high risks. Therefore, a microporous self-expanding (hybrid) stent graft composed of a thin, expandable, segmented polyurethane (SPU) membrane with micropores and a drug-delivery system was developed.

MATERIALS AND METHODS

A commercially available, self-expanding carotid stent was covered with a thin microporous SPU membrane fabricated by the dip-coating method and the excimer laser ablation technique, with an intraluminal coating of argatroban. Experimentally fabricated lateral-wall aneurysms in canine carotid arteries using venous pouches were occluded with the hybrid stent graft (bale-shaped pore density of 23.6%) on one side and a bare-metal stent on the other side without systemic antiplatelet therapy.

RESULTS

Angiography at 1, 6, and 12 months of stenting revealed that all arteries were patent without marked stenosis without systemic antiplatelet therapy. All aneurysms treated with hybrid stent grafts remained occluded throughout the 12-month period, while among those treated by bare-metal stents, 2 of 3 aneurysms were occluded at 6 months (67%) and only 1 of 3 aneurysms were occluded at 12 months (33%). Histology revealed that the novel hybrid stent graft had less intimal hyperplasia than the bare-metal stent. The hybrid stent graft was useful for the successful occlusion of these canine carotid aneurysms, even at 12 months.

CONCLUSIONS

The novel hybrid stent grafts are expected to overcome the disadvantages of fully covered stent grafts and simple bare-metal stents, while combining both their merits, and appear to be useful in the treatment of large or giant cerebral aneurysms.

Surgical treatment of giant serpentine aneurysm of A2-a3 segment distal anterior cerebral artery : technical case report

Objective

To report our surgical experience using in situ end-to-side bypass for giant serpentine distal anterior cerebral artery aneurysm, unsuitable for microsurgical clipping.

Methods

A 49-year-old woman presented with headache and intermittent loss of consciousness. The brain computed tomography scan revealed a partially calcified mass in the interhemispheric fissure. On cerebral angiography, that was giant (30×18 mm sized), serpentine aneurysm originating from the A2 to A3 segment of the distal anterior cerebral artery (DACA). The aneurysm was trapped with clips, and the right A3 segment to left A3 segment of DACA, end-to-side in situ bypass was performed. Surgical result was favorable, with no newly developed ischemic event in the acute recovery period. Postoperative angiography showed total occlusion of the aneurysm and good patency, with preserved distal flow.

Conclusion

Giant fusiform aneurysms of the DACA are extremely rare and can be particularly challenging to treat. End-to-side A3 : A3 bypass with aneurysm trapping could be a treatment modality for these locations.

STA-ACA bypass using the contralateral STA as an interposition graft for the treatment of complex ACA aneurysms: report of two cases and a review of the literature

Bypass surgery has been used as a remedy for the complex cerebral aneurysm, which was unsolved with the clipping method. However, little has been reported about bypass options for anterior cerebral artery (ACA) aneurysms. The authors experienced two patients with complex ACA aneurysms, large fusiform and large thrombosed aneurysms involving the distal A1 and proximal A2 segments, respectively. To achieve complete obliteration of the aneurysm, we performed a superficial temporal artery (STA)-ACA bypass using contralateral STA as interposition grafts with endovascular trapping without any ischemic events. These cases show that STA-ACA bypass using contralateral STA interposition graft is a feasible option to maintain blood supply to the ACA territory if a proximal ACA lesion requires trapping.

Thrombosed giant aneurysm of the distal anterior cerebral artery treated with aneurysm resection and proximal pericallosal artery-callosomarginal artery end-to-end anastomosis: Case report and review of the literature

BACKGROUND

Giant distal anterior cerebral artery (DACA) aneurysms are extremely rare, with only 32 cases reported in the literature. Most giant DACA aneurysms have features that make standard neck clipping difficult, and bypass surgery is sometimes required, although this surgery was performed in only three reported cases. This report presents the fourth case treated with bypass surgery.

CASE DESCRIPTION

A 69-year-old female presented with an unruptured thrombosed giant DACA aneurysm. She underwent wrapping operation 7 years before, but radiological imaging revealed enlargement of the aneurysm at the left pericallosal artery (PerA)-callosomarginal artery (CMA) junction. Before operation, three different strategies were considered for bypass surgery in case the neck could not be clipped. Aneurysm resection and left proximal PerA-CMA end-to-end anastomosis were successfully performed under intraoperative digital subtraction angiography (DSA) and motor-evoked potential (MEP) monitoring.

CONCLUSION

Most DACA aneurysms are located at the PerA-CMA junction. In some cases, adequate retrograde flow to the distal PerA from the posterior or middle cerebral artery can be expected, making distal PerA reconstruction unnecessary. Moreover, when the distal PerA is cut, proximal PerA-CMA end-to-end anastomosis can be easily performed because of reduced tension in both vessels. We therefore conclude that this strategy should be utilized for treating such patients. We also presented here the effectiveness of intraoperative modalities, such as intraoperative DSA and MEP monitoring, for performing a safe operation.

Surgical Treatment of a Large Fusiform Distal Anterior Cerebral Artery Aneurysm With In Situ End-to-Side A3—A3 Bypass Graft and Aneurysm Trapping

BACKGROUND AND IMPORTANCE:

Large fusiform aneurysms of the distal anterior cerebral territory are extremely rare and can be particularly challenging to treat. The circumferential pathology of fusiform lesions renders stand-alone clip or coil ablation unsatisfactory, and the deep, narrow corridor augments the difficulty of surgical approaches. In this setting, bypass procedures may be used to both treat the aneurysm definitively and preserve distal parent artery flow. We report a rare case of a large fusiform A3 aneurysm treated with trapping and concomitant end-to-side A3:A3 bypass.

CLINICAL PRESENTATION:

A 52-year-old man was evaluated after losing consciousness and experiencing a fall. A noncontrast computed tomography scan revealed a focal area of hemorrhage above the body of the corpus callosum, and computed tomography angiography showed a fusiform aneurysm of the right A3 artery. To treat the aneurysm definitively and preserve distal vessel flow, the patient was taken to surgery in anticipation of aneurysm ablation and cerebrovascular bypass. A large, fusiform right A3 aneurysm was identified. Intraoperative flow measurement demonstrated poor collateral circulation. The aneurysm was trapped with clips, and a right-to-left A3:A3 end-to-side in situ bypass was performed. Aneurysm occlusion and preserved distal vessel flow were confirmed with intraoperative angiography.

CONCLUSION:

Large fusiform aneurysms in the distal anterior cerebral artery region are rare, and the anatomy of these lesions and their vascular location render stand-alone surgical management technically challenging. End-to-side A3:A3 bypass combined with aneurysm trapping represents a feasible treatment strategy for lesions in this location.