Bifurcation dissecting aneurysm: tips and tricks to differentiate from saccular aneurysm.

Bifurcations are a common site for saccular aneurysms, but rarely can be a site for dissecting aneurysms. Identification of these aneurysms is extremely important because the management plan depends on it. We describe a rare case of a ruptured dissecting aneurysm at the right ICA bifurcation in a pre-teen child which posed a diagnostic dilemma but ultimately was successfully managed with flow diversion.

Ruptured Vertebral Artery Dissection Treated with Endovascular Intervention.

OBJECTIVE: A retrospective study of cases of endovascular treatment of dissection of the vertebral artery with subarachnoid hemorrhage was conducted. MATERIAL AND METHODS: Data were 11 cases of vertebral artery dissecting aneurysm (VADA) among 291 consecutive subarachnoid hemorrhage patients who underwent clipping or endovascular treatment at Ota Memorial Hospital. Classified into 4 patterns based on the location of the dissection and posterior inferior cerebellar artery (PICA): pre-PICA, post-PICA, involved PICA, and non-PICA. And one of the cases had bilateral vertebral artery dissection, and computational fluid dynamics analysis was included in the study. RESULTS: Ruptured VADA occurred in 11 of the 291 patients (3.8%). Endovascular treatment was performed in 8 of these 11 patients. Postoperative diffusion-weighted imaging detected no high-intensity lesions and no postoperative ischemic complications or rebleeding occurred in any patient. In a case of bilateral VADA, computational fluid dynamics analysis of very low or high wall shear stress at the dissection, low aneurysm formation indicator, and high oscillatory shear index may be considered rupture factors. CONCLUSIONS: Treatment strategies for each branching pattern of PICA can prevent rupture and avoid ischemic complications. And prediction of the rupture side is important in patients with bilateral dissection to consider the appropriate treatment and timing.

Extracranial internal carotid artery-dissecting aneurysm having a re-entry tear and causing lower cranial nerve palsies treated with flow-diverting stent: A case report.

Background: Extracranial internal carotid artery (ICA)-dissecting aneurysms (DAs) rarely cause re-entry tears and lower cranial nerve palsies. The therapeutic strategies for these pathologies are not well established. This report presents a case of an extracranial ICA -DA with a re-entry tear that caused lower cranial nerve palsy. Case Description: A 60-year-old man presented with left neck pain, hoarseness, and dysphagia. Physical examination and laryngoscopy determined palsies of the left cranial nerves IX, X, and XII. Digital subtraction angiography (DSA) revealed a DA in the left extracranial ICA, and three-dimensional DSA showed entry and re-entry tears in the intimal flap. Flow-diverting stents (FDSs) were placed on the lesion that covered the entry and re-entry tears because the symptoms did not improve after five weeks of conservative treatment. A post-procedural angiogram indicated flow stagnation in the DA. Symptoms improved remarkably immediately after the procedure, and the aneurysm was almost completely occluded six months later. Conclusion: Herein, an extracranial ICA -DA with a re-entry tear that caused lower cranial nerve palsy did not improve after five weeks of conservative treatment. FDS placement promptly resolved the aneurysm and symptoms. Thus, FDS placement may be an effective treatment option for extracranial ICA-DAs with re-entry tears or lower cranial nerve palsies.

Anesthetic management for cesarean section in two parturient with ascending aortic aneurysm: a case-based discussion.

BACKGROUND: The anesthetic management of parturients with ascending aortic aneurysm for cesarean section can be particularly challenging, primarily because of increased risk for aortic dissection or aneurysm rupture. CASE PRESENTATION: We present some aspects of the anesthetic management of two parturients with ascending aortic aneurysm for cesarean sections; amongst, the use of remifentanil with its effects on patient and newborn. We emphasize the importance of a cardio-obstetric team in the context of preoperative planning of such patients. Also, we reviewed some literature on the anesthetic management with its effect on peri-operative hemodynamic stability. CONCLUSION: Maintaining hemodynamic stability is paramount in the prevention of the rupture or dissection of ascending aortic aneurysm during labor of parturient.

Successful Internal Trapping of Vertebral Artery Dissecting Aneurysm Located between Double Origin of the Posterior Inferior Cerebellar Artery, Resulting in Antegrade Blood Flow: A Case Report.

Objective: The double origin of the posterior inferior cerebellar artery (DOPICA) is a rare variant of PICA. Vertebral artery dissecting aneurysm (VADA) with DOPICA is an extremely rare occurrence. Herein, we report a case of VADA located between DOPICA that was successfully treated with endovascular internal trapping. Case Presentation: A 48-year-old male, found collapsed at his workplace, was admitted to our hospital for emergency medical assistance. Head CT revealed a subarachnoid hemorrhage (Fisher group 3), and cerebral angiography revealed right VADA with DOPICA. The VADA was located distal to the proximal component of the posterior inferior cerebellar artery (PCPICA) and just proximal to the hypoplastic distal component of PICA (DCPICA). Emergency endovascular internal trapping was performed using a total of 13 coils from the distal end of the VADA to just the distal of the branching point of PCPICA. VADA was not visualized, and antegrade flow through DOPICA to the basilar artery was confirmed. Head magnetic resonance angiography (MRA) showed antegrade flow via DOPICA, and the patient was discharged home on Day 46 with a modified Rankin Scale 0. Conclusion: Endovascular internal trapping for VADA with DOPICA was considered useful, especially when VADA is distal to PCPICA and proximal to DCPICA.

Fenestrated Thoracic Endovascular Repair for Acute Type B Aortic Dissection with Isolated Left Vertebral Artery: A Case Report.

Thoracic endovascular aortic repair (TEVAR) of acute uncomplicated type B aortic dissection (uTBAD) has been discussed for its potential to prevent future aortic events. We present a fenestrated TEVAR in the case of an 86-year-old man with acute uTBAD with an isolated left vertebral artery (ILVA). The ILVA originated from the distal side of the left subclavian artery, the left subclavian artery, and the intramural hematoma with an ulcer-like projection extended close to the left subclavian artery. We selected a fenestrated stent graft to achieve a proximal healthy landing. This case demonstrates that a fenestrated stent graft for acute uTBAD is useful for preserving arch vessels.

Parent Artery Occlusion for a Dissecting Posterior Cerebral Artery Aneurysm in the P4 Segment Presenting with Ischemic Stroke and Rapid Growth: A Case Report.

A dissecting aneurysm in the P4 segment of the posterior cerebral artery (PCA) is extremely rare, and its treatment is sometimes challenging. Endovascular parent artery occlusion (PAO) was performed for an unruptured P4 segment dissecting PCA aneurysm presenting with ischemic stroke and rapid growth. A 70-year-old man was rushed to our emergency department due to a right-sided headache and a visual field defect. Head magnetic resonance imaging showed a right occipital lobe ischemic stroke, with right PCA occlusion and aneurysm formation in the P4 segment. The diagnosis was PCA dissection in the calcarine artery, and oral aspirin was started. Within a week, the dissecting aneurysm had enlarged progressively to 6.2 mm in diameter. Thus, PAO with coils was performed as a preventive measure against aneurysm rupture, assuming that complication risks were low because the tributary area of the dissecting PCA had already infarcted. A 6-Fr guiding sheath was introduced from the right brachial artery to the right vertebral artery, and a microcatheter/microguidewire was placed into the true lumen of the calcarine artery distal to the aneurysm. PAO with coils was performed, and the blood flow to the aneurysm was completely obliterated. After the treatment, the known infarction in the right occipital lobe was enlarged, but no new neurological symptoms developed. The patient was discharged independently on postoperative day 3. Treatment for a distal PCA dissecting aneurysm is challenging. PAO with coils is one of the reasonable choices, especially when a visual field defect has already developed.

Cerebral revascularization for complex vertebrobasilar artery dissecting aneurysms.

Vertebrobasilar artery dissecting aneurysms (VBDAs) are the most surgically challenging type of aneurysm. Cerebral revascularization is the ultimate treatment for complex VBDAs. We retrospectively analysed the characteristics, surgical outcomes and follow-up data of 21 patients who underwent cerebral revascularization to treat complex VBDAs from 2015 to 2022. According to the location of the aneurysm and the anatomic relationship between the VBDA and the PICA, VBDA patients were classified into four groups: aneurysms located at the VA with PICA involvement (10 patients), aneurysms located at the VA without PICA involvement (1 patient), aneurysms located at the basilar apex segment (1 patient) and aneurysms located at the basilar trunk segment (9 patients). A surgical algorithm for complex VBDAs was determined primarily by the location of the aneurysm, the status of the aneurysm and the ability of retrograde blood flow to reach the proximal vertebrobasilar artery. Surgical modalities for patients with aneurysms in the VA with PICA involvement included low-flow (OA-PICA) bypasses with aneurysm trapping, aneurysm excision or reconstructive clip in 8 patients and STA-PCA bypass combined with PICA preservation and aneurysm trapping in 2 patients. In patients with aneurysms in the VA without PICA involvement, aneurysm excision was performed without cerebral bypass. In patients with aneurysms in the basilar apex segment, high-flow bypass (ECA-RA-P2) with aneurysm trapping was performed. In patients with aneurysms in the basilar trunk segment, surgical modalities included high-flow bypasses (ECA-RA-P2 and LVA-RA-P2) with aneurysm trapping or proximal occlusion in 6 patients, ECA-RA-P2 bypass with partial proximal occlusion in 1 patient, ECA-RA-P2 bypass alone in 1 patient, and STA-PCA bypass with R-VA narrowing in 1 patient. Of the 21 patients, 20 experienced clinical improvement or no change, and 17 of 21 patients achieved favourable functional outcomes (mRS ≤ 2). However, one patient died of infarction and respiratory failure postoperatively. Aneurysms were completely obliterated in 13 patients, shrank in 5 patients and stabilized in 2 patients. The median follow-up period was 32.5 months. During the follow-up period, all bypasses were patent, and further clinical improvement was observed in 11 patients. Cerebral revascularization appears to be safe and effective for the treatment of complex VBDAs, and cerebral revascularization could act as a complementary treatment strategy.

Rapid presentation of a de novo intracranial aneurysm: illustrative case.

BACKGROUND: Intracranial aneurysms are prevalent, particularly with advancing age. De novo aneurysms, occurring independently from the initial lesion, pose a unique challenge because of their unpredictable nature. Although risk factors such as female sex, smoking history, and hypertension have been proposed, the mechanisms underlying de novo aneurysm development remain unclear. OBSERVATIONS: A 79-year-old female developed a de novo saccular aneurysm within a year after management of a ruptured vertebral artery dissecting aneurysm. Her complex clinical course involved subarachnoid hemorrhage with diffuse vasospasm, stent occlusion of a dissecting aneurysm, discovery of a right 7- to 8-mm de novo middle cerebral artery aneurysm at the 1-year magnetic resonance angiography follow-up, and successful coil embolization. LESSONS: This rare occurrence challenges established timelines, as most de novo aneurysms manifest over a longer interval. Studies have attempted to identify risk factors, yet consensus remains elusive, particularly regarding the influence of treatment modality on de novo formation rates. This unique case urges reconsideration of posttreatment surveillance protocols, proposing shorter intervals for imaging and more vigilant follow-up strategies to detect asymptomatic de novo aneurysms. Timelier identification could significantly impact patient outcomes by averting potential ruptures. This emphasizes the need for further research to delineate effective monitoring and preventive measures for these enigmatic lesions.

Right Sinus of Valsalva Aneurysm Rupturing into the Right Atrium and Dissecting into the Interventricular Septum.

The right sinus of the Valsalva aneurysm (SVA) rupturing into the right atrium (RA) and dissecting into the interventricular septum (IVS) is rare. The disease can be definitively diagnosed using two-dimensional (2D) echocardiography and color Doppler ultrasonography. Real-time biplane imaging and three-dimensional (3D) echocardiography offer new perspectives for viewing and diagnosing this disease.

Compatibility of the semijailing technique with extremely soft i-ED coils for ruptured blood blister-like and dissecting aneurysms: patient series.

BACKGROUND: Optimal treatment options for ruptured blood blister-like aneurysms (BBAs) and dissecting aneurysms (DAs) have not yet been established. Endovascular treatment may achieve vessel reconstruction with the preservation of antegrade blood flow; however, securing curative hemostasis at the fragile rupture point remains a major concern. OBSERVATIONS: Two ruptured BBAs and two ruptured DAs treated by stent-assisted coiling with the semijailing technique in the last 2 years are described herein. The devices used were braided stents and i-ED coils, which are new low-memory shape and extremely soft coils. Neither rebleeding nor ischemic complications were observed. All patients had a favorable outcome and showed no recurrence after treatment. LESSONS: All aneurysms were treated without ischemic complications or rebleeding. The good compatibility of braided stents and the new concept coils in stent-assisted coiling by the semijailing technique provides insight into these intractable hemorrhagic vascular pathologies.

Internal Carotid Artery Dissecting Aneurysm Associated with Persistent Trigeminal Artery: A Case Report.

BACKGROUND: Persistent trigeminal artery (PTA) is the most common vascular anastomosis between the carotid artery and vertebrobasilar systems. We report a very rare case of dissecting aneurysm in the right internal carotid artery (ICA) with ipsilateral PTA and discuss its clinical importance. CASE REPORT: A 38-year-old male presented to the emergency department with paroxysmal dysphasia for 6h. Brain magnetic resonance (MR) imaging showed acute cerebral infarction of the right corona radiata and right parietal lobe. Three-dimensional time-of-flight MR angiography (3D TOF MRA) revealed severe stenosis of the petrous segment (C1 portion) of the right internal carotid artery and a PTA originating from the right ICA cavernous segment (C4 portion), with a length of approximately 1.8cm and a diameter of approximately 0.2cm. The ICA segments are all named according to the Bouthilier classification. The basilar artery (BA) under union was well developed. The bilateral posterior communicating arteries were also present. One day later, the high-resolution vessel-wall MR demonstrated a dissecting aneurysm in the C1 portion of the right ICA. The length of the dissecting aneurysm is approximately 4.4cm, the diameter of the true lumen at the most severe stenosis is approximately 0.2cm, and the diameter of the false lumen is approximately 0.8cm. Subsequent digital subtraction angiography (DSA) confirmed a dissecting aneurysm in the C1 portion of the right ICA. The patient was treated conservatively and did not undergo interventional surgery. Four months later, head and neck MRA showed that the right ICA blood flow was smooth and that the dissecting aneurysm had disappeared. The Ethics Committee of Liaocheng People's Hospital approved the research protocol in compliance with the Helsinki Declaration. Written informed consent was obtained from the individual for the publication of any potentially identifiable images or data included in this article. CONCLUSION: Flow alteration with PTA may have influenced the formation of ICA dissection in this patient. Awareness of this is crucial in clinical practice because it can influence treatment options and intervention procedures.

Spontaneous triple vessel cervicocephalic artery dissection in a young gentleman: A case report.

INTRODUCTION: Cervicocephalic arterial dissections (CADs) occur in 3 cases per 100,000 individuals across all ages. Multiple simultaneous CADs are found in 13 to 22% of cases, and three or more dissections occur in approximately 2%. CADs might result from multifactorial intrinsic deficiencies of vessel wall integrity and extrinsic factors, e.g., minor trauma. CASE PRESENTATION: A young gentleman presented to the emergency department with a sudden onset of a spinning sensation of surrounding, left side arm weakness, blurring of vision, and an NIHSS score of 4. An urgent CT scan of the head and intracranial angiogram showed bilateral severe stenosis of the distal cervical segment of internal carotid arteries (ICAs) and right vertebral artery moderate stenosis at the V2 segment. He had been given IV TPA (Alteplase) within the 4.5-hour window. After 4 hours, the patient's GCS dropped from 15 to 10, and the NIHSS score increased from 4 to 24, followed by witnessed a generalized tonic-clonic seizure. Repeat urgent CT head showed no evidence of intracerebral hemorrhage (ICH). The patient was arranged for cerebral angiographic catheterization that showed bilateral flame-shaped occlusion of cervical ICA dissection. There is a mild focal narrowing of the right cervical vertebral artery, likely dissection. Routine laboratory blood workup for vasculitis was negative. During MICU admission, he had witnessed the right arm hemichorea-ballism spectrum abnormal movement. After the 6th-month follow-up, intracranial CT angiogram showed reduced caliber of the bilateral distal cervical course of the internal carotid arteries seen with residual dissection and focal outpouching of the right ICA representing pseudoaneurysm. DISCUSSION: The occurrence of multiple CADs suggests the presence of an underlying intrinsic arteriopathy, such as FMD, the presence of pseudoaneurysm, environmental triggers, cervical manipulation, and remote history of head or neck surgery. A study of the most extensive case series of patients with cervical artery dissection showed 15.2% of patients with multiple CAD. In most patients with multiple cervical artery dissections, antithrombotic treatment is effective, complete recanalization, and the outcome is favorable. Outside the window period of acute ischemic stroke, either anticoagulation or antiplatelet therapy is a recognized treatment for secondary ischemic stroke prevention due to extracranial artery dissection. For acute stroke or TIA patients caused by intracranial artery dissection, experts recommend antiplatelet therapy rather than anticoagulation. CONCLUSION: Simultaneous triple-vessel cervicocephalic arterial dissections are rarely reported condition. Multiple CADs are associated with underlying vasculopathy and environmental triggers, and a majority are recanalized with antithrombotic treatment with favorable outcomes. Antithrombotic treatment is effective in most patients with multiple CADs, and most expect complete recanalization. This case report guides physicians in the treatment and outcome of acute stroke due to multiple CAD.

Hemodynamic factors of spontaneous vertebral artery dissecting aneurysms assessed with numerical and deep learning algorithms: Role of blood pressure and asymmetry.

BACKGROUND AND OBJECTIVES: The pathophysiology of spontaneous vertebral artery dissecting aneurysms (SVADA) is poorly understood. Our goal is to investigate the hemodynamic factors contributing to their formation using computational fluid dynamics (CFD) and deep learning algorithms. METHODS: We have developed software that can use patient imagery as input to recreate the vertebrobasilar arterial system, both with and without SVADA, which we used in a series of three patients. To obtain the kinematic blood flow data before and after the aneurysm forms, we utilized numerical methods to solve the complex Navier-Stokes partial differential equations. This was accomplished through the application of a finite volume solver (OpenFoam/Helyx OS). Additionally, we trained a neural ordinary differential equation (NODE) to learn and replicate the dynamical streamlines obtained from the computational fluid dynamics (CFD) simulations. RESULTS: In all three cases, we observed that the equilibrium of blood pressure distributions across the VAs, at a specific vertical level, accurately predicted the future SVADA location. In the two cases where there was a dominant VA, the dissection occurred on the dominant artery where blood pressure was lower compared to the contralateral side. The SVADA sac was characterized by reduced wall shear stress (WSS) and decreased velocity magnitude related to increased turbulence. The presence of a high WSS gradient at the boundary of the SVADA may explain its extension. Streamlines generated by CFD were learned with a neural ordinary differential equation (NODE) capable of capturing the system's dynamics to output meaningful predictions of the flow vector field upon aneurysm formation. CONCLUSION: In our series, asymmetry in the vertebrobasilar blood pressure distributions at and proximal to the site of the future SVADA accurately predicted its location in all patients. Deep learning algorithms can be trained to model blood flow patterns within biological systems, offering an alternative to the computationally intensive CFD. This technology has the potential to find practical applications in clinical settings.

Flow diverters versus stent-assisted coiling in unruptured intracranial vertebral artery dissecting aneurysms.

OBJECTIVE: Flow diverters (FDs) have been used in unruptured intracranial vertebral artery dissecting aneurysms (IVADAs) with seemingly more favorable outcomes compared with stent-assisted coiling (SAC). However, the benefits of FDs over SAC in unruptured IVADAs need further evaluation. METHODS: This was a propensity score-matched, retrospective cohort study. Consecutive patients with unruptured IVADAs treated with FDs or SAC at the authors' hospital between January 2016 and December 2020 were reviewed. Propensity score matching at 1:1 was based on age, significant stenosis adjacent to aneurysmal dilatation, maximum diameter, and posterior inferior cerebellar artery involvement. Periprocedural cerebrovascular complications and angiographic and clinical outcomes were compared between the two matched groups. RESULTS: A total of 124 unruptured IVADAs in 123 patients (median age 53 [interquartile range 47-59] years; 101 men) were included. The FD and SAC groups included 65 and 59 IVADAs, respectively. Propensity score matching resulted in 47 matched pairs. The rates of immediate complete occlusion were significantly lower in the matched FD group than in the matched SAC group (6.4% vs 68.1%, p < 0.001). The rates of periprocedural cerebrovascular complications were comparable between the two matched groups (6.4% vs 6.4%, p > 0.99). At last follow-up, the rates of complete occlusion (89.4% vs 80.9%, p = 0.39) and favorable clinical outcomes (100.0% vs 97.9%, p > 0.99) were comparable, whereas the rate of recanalization was significantly lower in the matched FD group than in the matched SAC group (0.0% vs 12.8%, p = 0.03). Although the difference between the rates of in-stent stenosis was not statistically significant (17.0% vs 6.4%, p = 0.18), the difference in the effect measures was considerable. CONCLUSIONS: In unruptured IVADAs and compared with SAC, FDs provide comparable rates of periprocedural cerebrovascular complications, favorable clinical outcomes, and follow-up complete occlusion, lower rates of immediate complete occlusion and follow-up recanalization, and likely higher rates of in-stent stenosis.

A surgically salvaged case: emergency Root-Commando procedure for infective endocarditis and chronic dissecting aneurysm of the sinus of Valsalva.

The Commando procedure for infective endocarditis is a high-risk intervention. However, infective endocarditis involving the intervalvular fibrosa is fatal in the absence of surgery. A 41-year-old man with no medical history visited a doctor with chest pain and dyspnoea. Ascending aortic dissection and vegetation on the mitral valve were noted on echocardiography, so he was transferred to our hospital. The diagnosis was dissecting aneurysm of the sinus of Valsalva and acute heart failure due to aortic regurgitation, mitral regurgitation and infective endocarditis. We decided on emergency surgery. Intraoperatively, we confirmed abscess extending to the left atrial roof and destruction of the intervalvular fibrosa, so we performed the Root-Commando procedure. The patient was saved and discharged 47 days after transfer to our hospital through the reoperation on postoperative day 30.

Efficacy and predicting factors of multimodal treatment for ruptured intracranial vertebral artery dissecting aneurysms.

We aimed to investigate the efficacy of our multimodal strategies and propose a treatment algorithm for ruptured vertebral artery dissecting aneurysms (VADAs). This study included 41 patients treated at a single institution between 2015 and 2022. The treatment modalities were justified based on the collateral circulation and aneurysm location related to the posterior inferior cerebellar artery (PICA). Treatment outcomes and complications of each treatment group were analyzed. The association between the collateral blood flow and the postoperative vertebrobasilar ischemia (VBI) was also investigated. There were 17 post-PICA, 10 PICA-involved, 7 pre-PICA, and 7 non-PICA types. Reconstruction techniques included flow diversion devices (n = 11) and stent-assisted coiling (n = 3). Deconstruction techniques included coil trapping (n=17) and microsurgical parent artery occlusion with (n = 8) or without PICA revascularization (n = 2). Five (18.5%) of the deconstruction group had postoperative VBI. Overall favorable outcomes in both groups were observed in 70.7% of patients with a mean follow-up time of 21.5 months. Poor World Federation of Neurosurgical Societies grade (IV-V) was identified as a predictor of unfavorable outcomes (p = 0.003). In addition, the VA4/BA4 ratio > 0.22, the presence of collateral blood flow from the posterior communicating artery (PcomA), and a contralateral VA diameter > 2.5 mm were associated with a lower risk of postoperative VBI. In summary, the proposed strategic treatment in this study is pragmatic, yielding satisfactory results where a deconstructive technique should be used with caution, particularly when there is a flow mismatch or the absence of collateral PcomA in the vertebrobasilar circulation.

Clinical and Angiographic Outcomes of Endovascular Treatment for Acute Intracranial Vertebral Artery Dissecting Aneurysms Using Double-Overlapping Stents : Low-Profile Visualized Intraluminal Support within Enterprise Stents.

Objective: The use of reconstructive treatment with a double-overlapping stents has proven to be effective and safe in the current treatment of intracranial vertebral artery dissecting aneurysms (VADAs). We employed a combination of overlapping stents, using low-profile visualized intraluminal support (LVIS) within the Enterprise stent. This combination was chosen to minimize the outward bulging of the inner LVIS by overlapping it with the Enterprise stent while maintaining flow diversion and stability. This study aimed to evaluate the clinical and angiographic outcomes following the use of double-overlapping stents with LVIS within the Enterprise stent for the treatment of VADAs. Methods: From March 2016 to January 2022, total 28 patients with unruptured VADAs were treated with the double-overlapping stent technique using LVIS within an Enterprise stent in our institute. The Enterprise stent was deployed first, followed by the LVIS stent. Patient clinical and angiographic characteristics, procedural complications, and follow-up outcomes were retrospectively reviewed. Results: All 28 patients (18 males and 10 females) were successfully treated with double-overlapping stent deployment. There were no procedural complications or new neurological deficits in any patient. Of the 28 patients, four VADAs had posterior inferior cerebellar artery involvement. Procedure-related parent artery occlusion did not occur during the angiographic follow-up conducted 6 to 12 months after the procedure. Out of 28 patients, 24 showed complete healing, three had focal residual stenosis or dilatation with residual sac and only one had a residual dissecting flap with aneurysm. All patients, including the four patients, did not require any additional procedures. The postoperative modified Rankin Scale (mRS) scores were 0-1 for all patients. Conclusion: A double-overlapping stent, with a flow-diversion effect, is a safe and effective treatment for patients with VADAs. In particular, when using the LVIS stent within an Enterprise stent, it minimizes the bulging of the inner LVIS stent while maintaining flow diversion and stability. Therefore, both can be effectively utilized as overlapping stents.

Endovascular Embolization with n-Butyl Cyanoacrylate for Ruptured Distal Posterior Inferior Cerebellar Artery Dissecting Aneurysm.

Parent artery occlusion is a definitive treatment method for preventing rebleeding of dissecting aneurysms. We herein report a case of a ruptured distal posterior inferior cerebellar artery (PICA) dissecting aneurysm treated with internal trapping using n-butyl-2-cyanoacrylate (NBCA). A 65-year-old man visited our hospital with a complaint of headache and neck pain that began 1 week before his arrival. He had a history of spontaneous subarachnoid hemorrhage of unknown cause. Computed tomography of the brain revealed a small amount of subarachnoid hemorrhage, and distal subtraction angiogram showed a distal PICA dissecting aneurysm. We placed a guiding catheter in the left vertebral artery and an intermediate catheter in the PICA. A microcatheter was guided toward the proximal side of the aneurysm and was wedged into the parent artery. The dissecting aneurysm was treated with parent artery occlusion using 50% NBCA. The postoperative course was uneventful, and the patient was discharged 3 weeks after treatment without any neurological deficit. Parent artery occlusion with internal trapping using NBCA could be a safe and definitive treatment method for distal PICA dissecting aneurysms. Angiographical evaluation of the collateral network in the distal branch of PICA before embolization and wedged microcatheter technique in the parent artery are important for successful embolization using NBCA.