Microsurgical thrombectomy: where the ancient art meets the new era.

Mechanical thrombectomy (MT) is the leading treatment for acute large vessel occlusion (LVO). However, surgical thrombectomy (ST) may have a role in well selected LVO patients where MT failed to re-establish flow, the endovascular route is inaccessible, or where MT is a financially prohibitive or absent option (developing and poor countries). We compared the efficacy and efficiency between ST and MT, and described our operative experience and its potential application in the developing world. Clinical outcomes, procedural times, and efficacy of treatment were compared between the MT and ST of acute LVO between 2012 and 2022. Propensity score-matched analysis was also conducted to compare MT and ST. One-hundred nine patients fulfilled the study criteria (77 MTs vs 32 STs). Factors driving outcome were age (aOR: 0.95, 95%CI, 0.91-0.98), hemisphere side (aOR: 0.38, 95%CI, 0.15-0.96), and DWI-ASPECT (aOR: 1.39, 95%CI, 1.09-1.77) at presentation by the multivariate analysis. Times from door-start of procedure (P = 0.45) and start of procedure-recanalization (P = 0.13) were similar between treatment options. Propensity score-matched analysis found no significant difference for 2 treatment methods about time of door to recanalization (P = 0.155) and outcome (P = 0.221). The prognosticators of thrombectomy for acute LVO in patients with successful recanalization were age, affected hemisphere side, and DWI-ASPECT score. Our evidence shows that the efficacy of ST is similar to that of MT. There should be a place of ST for cases of mechanical failure or tandem cervical ICA and MCA occlusion. ST may be a temporizing LVO treatment option in healthcare systems where MT is inexistent or financially prohibitive to patients.

Complex intracranial aneurysms: a DELPHI study to define associated characteristics.

PURPOSE: Intracranial aneurysms present significant health risks, as their rupture leads to subarachnoid haemorrhage, which in turn has high morbidity and mortality rates. There are several elements affecting the complexity of an intracranial aneurysm. However, criteria for defining a complex intracranial aneurysm (CIA) in open surgery and endovascular treatment could differ, and actually there is no consensus on the definition of a "complex" aneurysm. This DELPHI study aims to assess consensus on variables defining a CIA. METHODS: An international panel of 50 members, representing various specialties, was recruited to define CIAs through a three-round Delphi process. The panelists participated in surveys with Likert scale responses and open-ended questions. Consensus criteria were established to determine CIA variables, and statistical analysis evaluated consensus and stability. RESULTS: In open surgery, CIAs were defined by fusiform or blister-like shape, dissecting aetiology, giant size (≥ 25 mm), broad neck encasing parent arteries, extensive neck surface, wall calcification, intraluminal thrombus, collateral branch from the sac, location (AICA, SCA, basilar), vasospasm context, and planned bypass (EC-IC or IC-IC). For endovascular treatment, CIAs included giant size, very wide neck (dome/neck ratio ≤ 1:1), and collateral branch from the sac. CONCLUSIONS: The definition of aneurysm complexity varies by treatment modality. Since elements related to complexity differ between open surgery and endovascular treatment, these consensus criteria of CIAs could even guide in selecting the best treatment approach.

From textbook to patient: a practical guide to train the end-to-side microvascular anastomosis.

Microvascular anastomosis is one of the most challenging neurosurgical techniques. Mastering this technique allows to perform intracranial bypass with arteries of small caliber usually placed in deep narrow surgical fields. The aim of this paper is to describe step by step end-to-side microanastomosis training method by using polyvinyl alcohol (PVA) hydrogel tubing as it is easily reproducible. The tubing comes in sizes from 0.3 mm to 5 mm and has a texture and consistency similar to real vessels. This is based on the Teishinkai Hospital anastomosis technique. Continuous practice in microvascular anastomosis is of great importance in training vascular neurosurgeon. The PVA hydrogel tubing described in this article are useful and cost-effective material in the training of microvascular anastomosis. This practical guide model is easy to set up for repeated practice, and will contribute to facilitate 'off-the-job' training by young neurosurgeons and the development and maintenance of microsurgical skills in both resident neurosurgeons and experts who wish to master the various levels of anastomosis technique. There is no shortcut to master this technique, only hard work and perseverance.

Aberrant drainage of posterior condylar emissary vein and abnormal orifice of hypoglossal canal: surgical implications in the transcondylar fossa approach for VA-PICA junction aneurysm.

BACKGROUND: The posterior condylar emissary vein (PCEV) and posterior condylar canal (PCC) are anatomical landmarks for identifying important structures like jugular tubercle and occipital condyle in surgical approach to the foramen magnum and condylar fossa. Several anatomical variations have been described. Drainage into the jugular bulb is found to be commonest. METHOD: A 70-year-old patient with unruptured vertebral artery-posterior inferior cerebellar artery (PICA) junction aneurysm-underwent surgical clipping via transcondylar fossa approach. RESULT: Preoperative computed tomography demonstrated an abnormal communication existed between the left-sided PCC and hypoglossal canal (HC). The PCEV was identified draining into a dilated venous channel/pouch at the "hip" of sigmoid sinus (junction of sigmoid sinus and jugular bulb). Intra-operatively, an occipital artery-PICA bypass was performed. The PCEV was skeletonized, coagulated, and divided to achieve hemostasis. The lateral and cranial drilling around PCC was successful at safeguarding the underlying contents of HC (in medial and caudal extent). CONCLUSION: Preoperative angiography and detailed morphometric analysis of the PCC were helpful in planning surgical approach-identifying and controlling the PCEV, and skeletonization of the PCC without compromising the hypoglossal nerve and anterior condylar emissary vein.

Differences Between Subarachnoid Hemorrhage Seen in Daily Practice and Aneurysms That Rupture During Follow-Up.

[Figure: see text].

Outcome of retreatment for recurrent saccular cerebral aneurysms: a propensity score-matched analysis.

Although endovascular or surgical treatment has been performed for preventing the rupture of saccular cerebral aneurysms (sCA), in some patients, the aneurysms may recur and require retreatment. We aimed to investigate the clinical and radiological outcomes of treating recurrent sCA. We retrospectively evaluated the data of 52 patients with 60 recurrent sCAs who were retreated and 1534 patients with 1817 sCAs who received initial treatment. The primary outcome was a recurrence of the aneurysm. Secondary outcomes were an additional treatment, rupture after treatment, and a neurological worsening, which was defined as an increase of 1 or more scores using the modified Rankin Scale at 12-month. Safety outcomes included postoperative ischemic and hemorrhagic complications. We compiled the 120 (60 each) propensity score-matched cohort based on a propensity score for the treatment of recurrent sCA. In the propensity score-matched cohort, recurrence after treatment was observed in 25% and 6.7% of cases in the retreatment and initial treatment groups, respectively. The odds ratio of recurrence after treatment was 4.7 (95% CI, 1.4-15; P = 0.011). The secondary and safety outcomes were not significantly different between the two groups. This study showed that the treatment of recurrent sCA was a risk factor for recurrence after treatment but not for additional treatment, rupture after treatment, or neurological worsening. Although decision-making regarding the treatment varies depending on the institutional protocols and personal experience of the physicians, endovascular or surgical retreatment could be performed without hesitation.

Microsurgery of residual or recurrent complex intracranial aneurysms after coil embolization - a quest for the ultimate therapy.

The long-term stability of coil embolization (CE) of complex intracranial aneurysms (CIAs) is fraught with high rates of recanalization. Surgery of precoiled CIAs, however, deviates from a common straightforward procedure, demanding sophisticated strategies. To shed light on the scope and limitations of microsurgical re-treatment, we present our experiences with precoiled CIAs. We retrospectively analysed a consecutive series of 12 patients with precoiled CIAs treated microsurgically over a 5-year period, and provide a critical juxtaposition with the literature. Five aneurysms were located in the posterior circulation, 8 were large-giant sized, 5 were calcified/thrombosed. One presented as a dissecting-fusiform aneurysm, 9 ranked among wide neck aneurysms. Eight lesions were excluded by neck clipping (5 necessitating coil extraction); 1 requiring adjunct CE. The dissecting-fusiform aneurysm was resected with reconstruction of the parent artery using a radial artery graft. Three lesions were treated with flow alteration (parent artery occlusion under bypass protection). Mean interval coiling-surgery was 4.6 years (range 0.5-12 years). Overall, 10 aneurysms were successfully excluded; 2 lesions treated with flow alteration displayed partial thrombosis, progressing over time. Outcome was good in 8 and poor in 4 patients (2 experiencing delayed neurological morbidity), and mean follow-up was 24.3 months. No mortality was encountered. Microsurgery as a last resort for precoiled CIAs can provide-in a majority of cases-a definitive therapy with good outcome. Since repeat coiling increases the complexity of later surgical treatment, we recommend for this subgroup of aneurysms a critical evaluation of CE as an option for re-treatment.

Role of RNF213 polymorphism in defining quasi-moyamoya disease and definitive moyamoya disease.

OBJECTIVE: Quasi-moyamoya disease (QMMD) is moyamoya disease (MMD) associated with additional underlying diseases. Although the ring finger protein 213 (RNF213) c.14576G>A mutation is highly correlated with MMD in the Asian population, its relationship to QMMD is unclear. Therefore, in this study the authors sought to investigate the RNF213 c.14576G>A mutation in the genetic diagnosis and classification of QMMD. METHODS: This case-control study was conducted among four core hospitals. A screening system for the RNF213 c.14576G>A mutation based on high-resolution melting curve analysis was designed. The prevalence of RNF213 c.14576G>A was investigated in 76 patients with MMD and 10 patients with QMMD. RESULTS: There were no significant differences in age, sex, family history, and mode of onset between the two groups. Underlying diseases presenting in patients with QMMD were hyperthyroidism (n = 6), neurofibromatosis type 1 (n = 2), Sjögren's syndrome (n = 1), and meningitis (n =1). The RNF213 c.14576G>A mutation was found in 64 patients (84.2%) with MMD and 8 patients (80%) with QMMD; no significant difference in mutation frequency was observed between cohorts. CONCLUSIONS: There are two forms of QMMD, one in which the vascular abnormality is associated with an underlying disease, and the other in which MMD is coincidentally complicated by an unrelated underlying disease. It has been suggested that the presence or absence of the RNF213 c.14576G>A mutation may be useful in distinguishing between these disease types.

[Combined Bypass and Cerebral Aneurysm Surgery:How to Choose and Practice?]

The treatment for cerebral aneurysms has been changing along with the advancements in endovascular treatment. In particular, the induction of a flow-diverter stent can treat even cavernous portion aneurysms, which have been difficult to treat without parent artery occlusion. The definite advantages of the open surgery are low recurrence rates, high angiographic outcome, and bypass. Herein, we describe the bypass method for treating cerebral aneurysms. The purpose of the bypass, difference between high-flow and low-flow bypasses, how to select the donor artery, and variation of bypass technique are described.

The re-anastomosis end-to-end bypass technique: a comprehensive review of the technical characteristics and surgical experience.

Re-anastomosis end-to-end bypass is a straightforward subtype of intracranial-intracranial reconstruction technique that has been utilized to treat complex aneurysms and skull base tumors. This simple technique involves connecting the cut ends of an afferent and efferent artery under added tension after excising the lesion. The current study aims to provide a detailed description of the technical pitfalls, ideal anatomical sites and indications, and clinical outcomes for intracranial complex disorders. A literature search was performed using the terms "intracranial-intracranial bypass," "re-anastomosis bypass," "reconstructive bypass," "end-to-end bypass," and "end-to-end anastomosis" to identify pertinent articles. Articles involving end-to-end re-anastomosis combined with other bypass methods were excluded. Computer-tablet-drawn illustrations of this technique are provided to enhance comprehension. Eighty-six patients who met our search and inclusion criteria were identified between 1978 and the present. However, comprehensive descriptions of medical records and neuroimaging were available in only 41 cases (40 complex aneurysms and a skull base tumor). Of 40 reported cases of complex cerebral aneurysms treated by this technique, the overall rate of full recovery without complication is 87.5% (35/40). Meanwhile, all aneurysms were completely eliminated from the circulation, with 92.5% of bypasses being patent. End-to-end re-anastomosis remains a simple modality in the microsurgical bypass armamentarium. Safe and effective surgical outcomes can be achieved in select cases that rarely involve perforators or branches.

Internal maxillary artery bypass for the treatment of complex middle cerebral artery aneurysms.

OBJECTIVEThe rapid innovation of the endovascular armamentarium results in a decreased number of indications for a classic surgical approach. However, a middle cerebral artery (MCA) aneurysm remains the best example of one for which results have favored microsurgery over endovascular intervention. In this study, the authors aimed to evaluate the experience and efficacy regarding surgical outcomes after applying internal maxillary artery (IMA) bypass for complex MCA aneurysms (CMCAAs).METHODSAll IMA bypasses performed between January 2010 and July 2018 in a single-center, single-surgeon practice were screened.RESULTSIn total, 12 patients (9 males, 3 females) with CMCAAs managed by high-flow IMA bypass were identified. The mean size of CMCAAs was 23.7 mm (range 10-37 mm), and the patients had a mean age of 31.7 years (range 14-56 years). The aneurysms were proximally occluded in 8 cases, completely trapped in 3 cases, and completely resected in 1 case. The radial artery was used as the graft vessel in all cases. At discharge, the graft patency rate was 83.3% (n = 10), and all aneurysms were completely eliminated (83.3%, n = 10) or greatly diminished (16.7%, n = 2) from the circulation. Postoperative ischemia was detected in 2 patients as a result of graft occlusion, and 1 patient presenting with subarachnoid hemorrhage achieved improved modified Rankin Scale scores compared to the preoperative status but retained some neurological deficits. Therefore, neurological assessment at discharge showed that 9 of the 12 patients experienced unremarkable outcomes. The mean interval time from bypass to angiographic and clinical follow-up was 28.7 months (range 2-74 months) and 53.1 months (range 19-82 months), respectively. Although 2 grafts remained occluded, all aneurysms were isolated from the circulation, and no patient had an unfavorable outcome.CONCLUSIONSThe satisfactory result in the present study demonstrated that IMA bypass is a promising method for the treatment of CMCAAs and should be maintained in the neurosurgical armamentarium. However, cases with intraoperative radical resection or inappropriate bypass recipient selection such as aneurysmal wall should be meticulously chosen with respect to the subtype of MCA aneurysm.

Microsurgical dissection of Sylvian fissure-short technical videos of third generation cerebrovascular neurosurgeons.

BACKGROUND: Multiple intracranial pathologies, including aneurysms of the middle cerebral artery, distal basilar artery, and suprasellar pathologies require the microsurgical opening of the Sylvian fissure. Delicate splitting of the arachnoid and safe microdissection of the veins, arteries, and brain parenchyma is the key to successful surgery through the Sylvian fissure corridor. We hypothesize that the geographical and historical environment in which neurosurgeons learn their operative skills is subject to a number of extrinsic influences, including cultural nuances of surgical techniques. Here we try to illustrate some cultural differences and technical aspects of the opening of the Sylvian fissure by four "third generation" cerebrovascular neurosurgeons from three different continents. METHODS: In the video analysis, various microsurgical aspects, including the opening style of the Sylvian fissure, handedness, use of sharp or blunt microinstruments, use of retractors, use of high magnification, and handling of bridging veins are presented. RESULTS: The video illustrates the two distinct Sylvian fissure opening styles, namely sharp and blunt microdissection, as well as the extent of the opening namely a wide and focal splitting. CONCLUSION: The edited video underlines nuances and differences of a few major technical aspects that are perhaps typical to certain surgical environments and cultures. These microsurgical nuances and styles are useful pearls that can be mastered with training by any novice neurosurgeon.

[Transarterial Embolization of Intraorbital Dural Arteriovenous Fistula:A Case Report].

Intraorbital dural arteriovenous fistula(dAVF)is a very rare disease; therefore, an optimal treatment strategy has not yet been established. Here, we describe a case of successful dAVF treatment by performing transarterial embolization(TAE)with n-butyl-2-cyanoacrylate(NBCA). A 66-year-old male presented with right conjunctival injection, with no history of trauma. Magnetic resonance imaging(MRI)demonstrated a flow void in the right orbit. Digital subtraction angiography(DSA)revealed an AVF fed by a branch of the right ophthalmic artery(OA)and draining into the dilated right superior ophthalmic vein(SOV). A transvenous embolization(TVE)was planned, but it could not be performed because the facial vein was meandering. Hence, TAE with NBCA was performed, and the AVF was successfully occluded by this method. There has been no recurrence of intraorbital dAVF in three months since the treatment. Several recent studies have reported that TAE is an effective treatment for intracranial dAVF. However, there are insufficient reports of TAE with NBCA for intraorbital dAVF treatment. The anatomy of the OA needs to be known for the success of TAE in treating intraorbital dAVF, because TAE is a high-risk treatment. In this paper, we report a case wherein TAE with NBCA was performed for intraorbital dAVF and further review the other treatment options.

Surgical treatment of unruptured distal basilar artery aneurysm: durability and risk factors for neurological worsening.

BACKGROUND: Distal basilar artery aneurysms (DBAs) consist of basilar apex and basilar artery-superior cerebellar artery bifurcation (BA-SCA) aneurysms. The authors aimed to investigate clinical and radiological differences between two locations and to evaluate the 12-month surgical outcome in unruptured DBAs. METHODS: Fifty-six consecutive patients who underwent surgical treatment (37 basilar apex and 19 BA-SCA aneurysms) between April 2012 and February 2016 were retrospectively evaluated. In patients with a preoperative modified Rankin Scale score (mRS) of more than 1, neurological worsening (NW) was defined as an increase in one or more mRS. In patients without symptoms, NW was defined as mRS ≥2. RESULTS: The mean age of the patient population was 64 ± 9.6 years, and 48 (86%) were female. Mean follow-up period was 2.6 ± 0.94 years. An excellent (mRS 0 to 1) outcome was archived in 31 (55%), 45 (82%), and 48 (87%) patients at 30 days, 6 months, and 12 months, respectively. Clinical and radiological characteristics showed no differences between two locations. One early death (1.8%) and one severe morbidity (1.8%) due to rupture were observed. The postoperative annual rupture rate was 1.4% overall (145 patient-years). After adjustment for age and location, large or giant DBA was related to 30-day and 12-month NW [n = 22 (39%) and n = 6 (11%); p = 0.009 and 0.002, respectively], aneurysm localization in the interpeduncular cistern (LIC) and perforator territory infarction were related to 30-day NW (p = 0.002 and 0.002), and DBA that needed bypass surgery and previously treated recurrent DBA were related to NW at 12 months (p = 0.017 and 0.001). Multivariate analysis showed that LIC was significantly related to perforator territory infarction (p = 0.003). CONCLUSIONS: Clinical and radiological characteristics were not different between basilar apex and BA-SCA aneurysms; therefore, they should not be discussed separately. To avoid neurological worsening, results of surgical treatment for unruptured DBAs should be improved.

C1 transverse process-hyoid bone line for preoperative evaluation of the accessible internal carotid artery on carotid endarterectomy: technical note.

BACKGROUND: The preoperative imaging diagnosis of the distal portion of the internal carotid artery (ICA) is extremely important for carotid endarterectomy (CEA). Herein the authors defined a line from the C1 transverse process to the hyoid bone (C1-H line) and evaluated whether the line can be used to predict an accessible ICA in CEA. METHODS: A cross point between the C1-H line and distal ICA was analyzed using three-dimensional computerized tomographic angiography (3D-CTA) in 20 patients. The C1-H line was compared to the line drawn from the mastoid process to the mandible (M-M line). Intraoperative exposure of the distal ICA was evaluated using both lines. Furthermore, the distance of each line from the C2 vertebra was measured to identify the distance difference of each line in relation to the cervical posture. RESULTS: A distal ICA exposed at a cross point of the C1-H line corresponded well with the intraoperative findings. The cross point between the C1-H line and distal ICA was positioned at an average of 7.0 ± 0.7 mm cranially in comparison to the M-M line. The C1-H line showed smaller distance differences at different cervical positions than the M-M line. The C1-H line moved an average of 2.8 ± 2.5 mm from a cervical neutral position to an extensional one in the perpendicular direction. CONCLUSION: The C1-H line measured by 3D-CTA is a simple and useful indicator of the distal ICA exposure in the preoperative diagnosis for CEA.

Distal internal carotid artery dissection due to the carotid shunt during carotid endarterectomy.

We described two cases of shunt-related distal internal carotid artery (ICA) dissection from high cervical ICA stenosis. These cases suggest that for high cervical internal carotid endarterectomy, surgeons should reconsider using a carotid shunt to reduce the risk of ICA dissection.

Occipital artery-to-posterior inferior cerebellar artery anastomosis with multiple-layer dissection of suboccipital muscles under a reverse C-shaped skin incision.

Although occipital artery (OA)-to-posterior inferior cerebellar artery (PICA) anastomosis is the most familiar reconstruction for posterior cerebral circulation, the procedure is considered difficult because of the anatomical complex course of OA and the depth of the operative field at the anastomosis site. Therefore, we attempted a safe and reliable method for OA-to-PICA anastomosis under multiple-layer dissection of suboccipital muscles and a reverse C-shaped skin incision. We reviewed the clinical records of patients who underwent OA-to-PICA anastomosis in our institute, and report the outcome with special emphasis on graft patency and surgical complications. Nine patients are described. In one patient the bypass was accomplished at the cortical segment of the PICA and in all others at the caudal loop. The average time for de-clamping the PICA was 29 min and 29 s. Although the overall graft patency rate was 100%, one patient showed a new medulla infarction at the time of post-operatory three-dimensional computed tomography angiography. Besides a secure OA-to-PICA anastomosis, this technique allows safe harvest of the OA and the creation of a shallow and wide anastomosis field.

The graft kinking of high-flow bypass for internal carotid artery aneurysm due to elongated styloid process: a case report.

Elongated styloid process is an often-caused symptom due to the compression of neighboring structures. We present a case of a graft kink of high-flow bypass due to an elongated styloid process and describe the technical pitfalls encountered when creating a graft route from the standpoint of the anatomical site.

Basal vein of Rosenthal classification: the key to venous outflow of the deep sylvian fissure.

OBJECTIVE: Mastery of sylvian fissure dissection is essential to access lesions within the deep basal cisterns. The deep sylvian vein and its tributaries play a major role during access to and beyond the carotid cistern through the sylvian fissure and determine the complexity of microdissection. Preserving the venous outflow during sylvian fissure dissection is the best reliable strategy to prevent postoperative venous strokes or venous hypertension. The authors report the role of the basal vein of Rosenthal (BVR) in the venous outflow pattern of the deep sylvian cistern. METHODS: The authors analyzed 262 consecutive surgical cases involving sylvian fissure dissection from 2015 to 2017. Inclusion criteria were complete sylvian fissure dissection for the treatment of intracranial aneurysms. Exclusion criteria were giant size (aneurysm diameter > 24 mm), meningitis, subarachnoid hemorrhage within the sylvian cistern, absence of 4D CT angiography, and previous surgery. Retrospective radiological and operative video reviews were carried out to assess the association between the superficial sylvian vein and the BVR. The authors analyzed the course of the BVR and the patterns of venous drainage of the sylvian cistern. The surgical difficulty of sylvian fissure dissection was rated by the authors to study the operative significance of the venous patterns encountered. Two clinical cases are described to illustrate the proposed BVR classification. RESULTS: A total of 97 patients met the selection criteria. The most frequent type of BVR was immature (diameter < 0.5 mm, 68%). When the BVR was incompletely developed or absent (immature type), the deep sylvian veins drained through a middle sylvian vein in 70% of cases, requiring advanced sylvian fissure dissection techniques. However, when the BVR was completely developed (32%), the middle sylvian vein was found in a minority of cases (6%), which allowed for an unobstructed transsylvian corridor. Interrater and test-retest reliability of the surgical difficulty was greater than 0.9. CONCLUSIONS: Preoperative assessment of the BVR anatomy is key to predict the deep sylvian venous pattern. The authors provide objective evidence supporting the reciprocal relationship between the type of BVR and the presence of a middle sylvian vein and the deep sylvian venous outflow. An immature BVR should alert the neurosurgeon of the high likelihood of finding a complex deep venous pattern, which may drive surgical planning.

Bypass Surgery for Vertebral Artery and Posterior Inferior Cerebellar Artery Fusiform Aneurysms: Surgical Technique and Key Lessons.

Fusiform vertebral artery (VA) aneurysms are challenging to treat due to their pathophysiology, morphology, and anatomic location.1,2 Endovascular treatments are considered to be a widely adopted safe option for this pathology.1 Open microsurgical treatment is considered for complex anatomy, important branch involvement, poor collateral flow, or failed endovascular therapy.3-7 This report aims to show the flow-replacement strategy and bypass technique for a VA aneurysm with complex anatomy and branch involvement. A 24-year-old man presented to our clinic with a bilateral fusiform VA aneurysm discovered during workup of progressive headaches. Further investigation revealed that the left-side aneurysm was mostly thrombosed and the posterior inferior cerebellar artery arose from the aneurysm dome with a fusiform enlargement within a few millimeters from the branching point. After evaluating all management options, the patient decided on surgical treatment of the left VA aneurysm. We performed an occipital artery to posterior inferior cerebellar artery end-to-side anastomosis distal to the fusiform enlargement, followed by trapping of the aneurysm and dome resection (Video 1). Antegrade flow to the distal VA was reestablished using a radial artery interposition graft, thus preventing any flow alterations that may cause growth or rupture of the contralateral aneurysm caused by increased hemodynamic stress if the ipsilateral VA flow is not preserved.8 After in-hospital physical rehabilitation, the patient was discharged with a modified Rankin Scale score of 1. The contralateral aneurysm is managed with serial imaging and treatment will ensue if there is clinical-radiologic evolution. The patient consented to the procedure and publication of his image.