Endovascular Treatment of "Donut-Shaped" Aneurysm-A Case Series.

Background and Objectives: Partially thrombosed aneurysms represent a subset primarily found within large and giant aneurysms. The presence of an intraluminal thrombus can cause an aneurysm to present in different shapes upon angiographic examination. We present a series of five cases of "donut-shaped" aneurysms observed over the past decade at the Clinic for Neurosurgery in the University Clinical Centre of Serbia. Materials and Methods: The management of "donut-shaped" aneurysms was accomplished through endovascular interventions, employing techniques such as the deployment of flow-diverting stents or a combination of stent placement and coil embolization. Results: Four out of five patients underwent endovascular treatment, yielding positive outcomes with complete thrombosis of the aneurysms during follow-up. The fifth patient was successfully diagnosed; however, due to their deteriorating condition, treatment was not feasible. Conclusions: Given the potential life-threatening complications associated with this entity, accurate diagnosis and appropriate management are crucial. In our cohort, endovascular interventions demonstrated efficacy in the majority of cases, underscoring the significance of this approach in treating "donut-shaped" aneurysms. Nevertheless, considering the rarity of this condition, further research is justified to refine diagnostic and therapeutic strategies for these complex intracranial vascular anomalies.

Recurrent reversible in-stent-stenosis after flow diverter treatment.

Flow diverter stents (FDS) are well established in the treatment of intracranial aneurysms which are difficult to treat with conventional endovascular techniques. However, they carry a relatively high risk of specific complications compared to conventional stents. A minor but frequent finding is the occurrence of reversible in-stent-stenosis (ISS) that tend to resolve spontaneously over time. Here, we report the case of a patient in their 30s who was treated with FDS for bilateral paraophthalmic internal carotid artery (ICA) aneurysms. ISS were found at the respective early follow-up examinations on both sides and had resolved at the 1-year follow-up examinations. Surprisingly ISS reoccurred at both sides in later follow-up examinations and again resolved spontaneously. The recurrence of ISS after resolution is a finding that has not been described previously. Its incidence and further development should be investigated systematically. This might contribute to our understanding of the mechanisms underlying the effect of FDS.

Ghost twisting of the dual-layer flow-diverting stent.

The twisting phenomenon of the flow diverter stents rarely occurs, but it recently became relatively well-recognized. There have been few reports on single-layer flow diverters only. The Flow Redirection Endoluminal Device (FRED) (MicroVention, Tustin, California) has a unique design characterized by a braided dual-layer self-expanding stent. There have been no reports on the twisting phenomenon of FRED. This study reports two cases of acute in-stent blood flow disturbances after the deployment of FRED in a patient with intracranial aneurysms associated with "ghost twisting." In this phenomenon, the inner layer does not expand with the coning deformation, even though the outer layer is fully open. This was confirmed through high-resolution cone-beam computed tomography, but not conventional angiography. The two cases were successfully treated using balloon angioplasty and showed favorable outcomes. The structural issue of "ghost twisting" was a possible underlying factor for the ischemic complications associated with FRED deployment.

Flow diverter stent treatment for unruptured supraclinoid segment internal carotid artery aneurysms: a Turkish multicenter study.

OBJECTIVE: Despite the relatively high success of surgical clipping of supraclinoid segment aneurysms of the internal carotid artery (ICA), flow diverter (FD) stent therapy is becoming increasingly used for these aneurysms. This study aims to evaluate the characteristics of FD placement for unruptured ICA supraclinoid segment aneurysms at 6 different centers with different experience levels in Türkiye. METHODS: In this retrospective, multicenter study, the authors reviewed the demographic information, aneurysm shape/dimensions (neck, aspect ratio, dome/neck ratio, and maximum diameter), preoperative antiplatelet regimen, FD stent brand, perioperative complications, intervention time, clinical (modified Rankin Scale) and radiological (O'Kelly-Marotta [OKM] grading scale) outcomes, and follow-up time of 54 patients. RESULTS: A total of 55 interventions for 61 aneurysms (58 supraclinoid ICA aneurysms) were performed in the 54 patients included in the study. The female/male ratio in this population was 44/10, and the mean age was 53.5 ± 13.6 (range 21-82) years. The most common form and location of the aneurysms were saccular 91.4% (53/58) and ophthalmic segment 69% (40/58), respectively. The preferred antiplatelet regimen was acetylsalicylic acid plus ticagrelor 50% (27/54). The overall complication rate was 25.5% (14/55), and the mean follow-up time was 25.76 ± 17.88 months. The successful radiological outcome (OKM grade C or D) rate at the 6-month follow-up was 92.6%. No perioperative complications led to any permanent or transient neurological deficit. CONCLUSIONS: The results of this first multicenter study evaluating FD stent use for unruptured ICA supraclinoid segment aneurysms showed that FD stent treatment is a feasible method for replacing clipping and coil embolization with manageable complications and a high success rate.

Personality change after 'flow diverter implantation' for intracranial aneurysm in a patient with stroke: A case report.

OBJECTIVE: This study aimed to present a patient with psychiatric symptoms that occur after flow diverter stent placement in a posterior communicating artery (PComA) aneurysm in a patient. DESIGN: A case study. METHOD: We performed cranial magnetic resonance imaging (MRI), magnetic resonance angiography, computed tomography angiography, neuropsychological tests, Levenson Self-Report Psychopathy Scale (LSRP), and a 25-item version of the Wender Utah Rating Scale (WURS-25). The patient's recent MRI was compared with previous MRIs. Neuropsychological testing consisted of a clinical interview, clinical assessment of frontal lobe syndrome, and tests evaluating the prefrontal cortex functions (Wisconsin Card Sorting Test-128 card version and Iowa Gambling Test). RESULTS: Our results showed that the patient's personality change and psychiatric symptoms occurred after the stent placement. Symptoms were still present at evaluation two and a half years after stent placement. CONCLUSION: The study demonstrates personality changes and psychiatric symptoms that might occur as complications following the placement of a flow diverter for incidentally detected aneurysm.

Management of giant internal carotid aneurysm by extracranial-intracranial bypass and flow diverter stent.

Flow diverter stents have become the standard approach to managing intracranial aneurysms; however, in some cases of complex, wide-necked aneurysms, poor outcomes due to stent occlusion have been reported. We report the case of a giant internal carotid artery aneurysm treated by high-flow extracranial-intracranial (EC-IC) bypass with flow diverter deployment. Seven months post-operatively, radiographic imaging demonstrated occlusion of the stent and parent artery, with further ischemic events prevented by collateral flow from the high flow bypass. This case demonstrates the continued utility of EC-IC bypass in the endovascular era, especially as a rescue tool in cases of delayed stent occlusion.

Silk Vista Baby flow diverter stent for ruptured intracranial aneurysms: a retrospective observational study.

PURPOSE: Flow diversion changed the approach to complex intracranial aneurysms, leading to a widespread use and a rapid technological evolution. Indeed, indications continued to expand, including ruptured intracranial aneurysms in selected cases. Recently, new devices have been designed specifically to target smaller vessels. Therefore, we conducted a multicenter study to evaluate clinical outcome, complications, and occlusion rate of patients with ruptured aneurysms treated with new generation low profile Silk Vista Baby (SVB) flow diverter stent (FD). METHODS: We performed a retrospective observational study on consecutive patients who underwent treatment with SVB for ruptured aneurysms at 12 Italian centers. Primary end point was favorable clinical outcome rate, defined as modified ranking score (mRS) of 0-2 at the 3 months. Secondary outcomes were complication rate, aneurysm re-rupture, and complete aneurysm occlusion at last radiological follow-up. RESULTS: Twenty-five patients were included; at 3 months' follow-up, 19 patients (79.1%) had favorable clinical outcome (mRS 0-2). Three patients (12.5%) died during follow-up. In-stent thrombosis occurred in two cases (8.3%), managed with glycoprotein IIb/IIIA and intra-stent angioplasty, without clinical consequences. In 18 (85.7%) patients, complete occlusion at 3 months was demonstrated. No rebleeding occurred during follow-up. Presentation with unfavorable World Federation of Neurosurgical Societies grading system (WFNS) and posterior circulation location were both significantly correlated with unfavorable clinical outcome (p = 0.005 and p = 0.02). CONCLUSIONS: Our data suggests that low profile FD treatment of ruptured intracranial aneurysms located distally of the circle of Willis is feasible. New generation low profile FD may represent an alternative option in carefully selected cases.

Predictors of flow diverter stent in large and giant unruptured intracranial aneurysms, single-center experience.

BACKGROUND: Flow diversion with or without coiling has been established as the treatment of choice for large unruptured aneurysms. This study aims to assess possible predictors for radiological and clinical outcome such as location of the aneurysm (anterior or posterior circulation), complexity by a branching artery, bifurcation, and adjuvant coiling. METHODS: This study was conducted on 65 consecutive patients with 65 large, unruptured intracranial aneurysms (size ≥ 10 mm) treated with flow diverters. Follow-up angiography was done for 60 patients (92.3%) at 12 ± 8.6 months range from 3 to 36 months. RESULTS: Complete occlusion was achieved in 50 from 60 aneurysms (83.4%), while 8 aneurysms (13.3%) had neck remnant, and another two aneurysms (3.3%) remained with aneurysmal remnant. Periprocedural complications were encountered in 14 patients (21.5%) with morbidity in six patients (9.2%) and mortality in one patient (1.5%). In a multivariate logistic regression, anterior versus posterior location was less likely associated with worse outcome; adjusted OR (95% CI) of 0.16 (0.07-0.01), p = 0.006. Complete occlusion in complex aneurysms with branching artery was 60% versus 88% in simple aneurysms without branching artery (p-value = 0.04). CONCLUSIONS: Flow diverter deployment of a large, unruptured aneurysm in the anterior circulation might have a better outcome than one in the posterior circulation. Flow diverter of aneurysms with branching artery or at bifurcation might be associated with aneurysm persistence and complications respectively.

Flow diverter stents for pediatric traumatic carotid cavernous fistula: a case report and literature review.

A 10-year-old, male patient with a head injury caused by a fall presented with chemosis, exophthalmos, right orbital bruit, and intracranial venous reflux, based on which posttraumatic carotid cavernous fistula (CCF) was diagnosed. Coil embolization was semi-urgently performed for the dangerous venous drainage. After the treatment, right abducens nerve palsy newly appeared. To treat the neurological symptoms and preserve the parent artery, curative endovascular treatment using a pipeline embolization device (PED) with coil embolization was performed after starting dual antiplatelet therapy (DAPT). The CCF and abducens nerve palsy finally resolved, and the internal carotid artery (ICA) was remodeled. Use of the PED with adjunctive coil embolization was effective and safe in the present case of pediatric traumatic direct CCF.

Emergency endovascular treatment of cavernous internal carotid artery acute bleeding with flow diverter stent: a single-center experience.

BACKGROUND AND OBJECTIVE: To describe our single-center experience in the treatment of cavernous internal carotid artery (ICA) acute bleeding with flow diverter stent (FDS), as a single endovascular procedure or combined with an endoscopic endonasal approach. METHODS: We analyze a case series of 5 patients with cavernous ICA acute bleeding, i.e., 3 iatrogenic, 1 post-traumatic, and 1 erosive neoplastic. After an immediate nasal packing to temporarily bleeding control, patients underwent digital subtraction angiography (DSA) to identify the site of the ICA injury. A concomitant balloon occlusion test (BOT) was performed, to exclude post-occlusive ischemic neurological damage. An FDS was placed with parallel intravenous infusion of abciximab in 3 cases and tirofiban in 2 cases. In two patients, an innovative "sandwich technique" combining the endovascular reconstruction with an extracranial intrasphenoidal cavernous ICA resurfacing with autologous flaps or grafts by endoscopic endonasal approach was performed. RESULTS: No patient had periprocedural ischemic-hemorrhagic complications. All patients had a regular clinical evolution, without general complications or new onset of focal neurological deficits. No further bleeding occurred in 3 patients, while 2 cases experienced a mild rebleeding in a period ranging from 5 to 15 days after the endovascular procedure. In these two cases, we proceeded with an endoscopic endonasal procedure to resurface the exposed ICA wall in the sphenoid sinus. CONCLUSIONS: Although the treatment of choice for cavernous ICA acute bleeding remains the occlusion of the injured vessel, in cases of poor hemodynamic compensation at the BTO, the endovascular FDS emergency placement can be effective. A combined endoscopic endonasal technique to support the extracranial side of the vessel using autologous flaps or grafts can be performed to prevent the risk of rebleeding.

Successful treatment of giant cavernous carotid artery aneurysm in a child using a flow diverter stent.

Giant intracranial aneurysms are extremely rare in children. We present such a case, describe angiographic appearances and successful treatment using a flow diverter stent.

Endovascular management of spontaneous delayed migration of the flow-diverter stent.

BACKGROUND AND PURPOSE: Spontaneous delayed migration of the flow-diverter stent (FD) is an unusual complication that can be fatal. The purpose of this study is to report our experience and review the literature for the management of delayed FD migration. MATERIALS AND METHODS: Between November 2013 and June 2017, 122 patients treated by FD at our institution were enrolled. We also performed a comprehensive review of the literature. RESULTS: Six patients (4.9%) were found to have spontaneous delayed migration of their FD. The device migrated proximally in 4 patients and distally in 2 patients. One patient had temporal lobe infarction due to stent migration, and another had subarachnoid haemorrhage (SAH). Three patients were treated with a 2nd or 3rd FD, while 2 were treated with stent-assisted coiling, and one was treated with sacrifice of the parent internal carotid artery. According to our results and the literature, the prevalence rate of delayed FD migration ranges from 2.2% to 4.9%, and the mortality and morbidity rate of delayed FD migration is 40%. CONCLUSIONS: Neuro-interventionalists should be aware of this complication and be familiar with risk factors, preventive methods and treatment options. If there is any concern regarding the size or position of the FD, early imaging follow-up and endovascular treatment should be indicated.

Utility of 3D rotational angiography road map in flow diverter deployment in a distal dissecting MCA aneurysm.

Distal, dissecting, middle cerebral artery (MCA) aneurysms are changing surgically and endovascularly. Endovascular treatment requires flow diverter stenting. A good vessel visualization is crucial for safe navigation. Three-dimensional rotational digital subtraction angiography (3D-DSA) is used routinely in diagnostic imaging. The utilization of the 3D-DSA road map in vessel navigation and stent deployment is novel. An illustrative video of a distal, dissecting left MCA aneurysm treated with flow diverter stenting is presented. The technical issues were distal location, dissecting nature with double lumen, proximal stenosis, and vessel curves. The 3D-DSA road map helped to enhance visualization with a safer procedure.The video can be found here: https://youtu.be/sS3o1Z0P8WE.

Endovascular management of basilar artery occlusion secondary to fusiform aneurysm with intraluminal thrombus.

Acute basilar artery occlusion is one of the most devastating subtypes of ischemic stroke with an extremely high morbidity and mortality rate. The most common causes include embolism, large-artery atherosclerosis, penetrating small-artery disease, and arterial dissection. The heart and vertebral arteries are the main source of emboli in embolic basilar occlusions. The authors present an uncommon acute basilar occlusion secondary to a fusiform aneurysm with intraluminal thrombus. The patient underwent a mechanical thrombectomy with successful recanalization, but persistent intraluminal thrombus. The authors discuss the management dilemma and describe their choice for placement of flow diverter stents.The video can be found here: https://youtu.be/XzBdgxJPSWQ.

Long-term follow-up in the endovascular treatment of intracranial aneurysms with flow-diverter stents: update of a single-centre experience.

INTRODUCTION: Flow-diverter stents are becoming a useful tool in treating patients with intracranial aneurysms with suitable anatomical feature. Purpose of this study was to evaluate effectiveness and safety of endovascular treatment with flow-diverting stents (FD) in unruptured intracranial aneurysms. METHODS: From May 2009 and May 2014, we treated 49 patients with a total of 58 aneurysms, with FD technique. All patients were treated electively, under general anesthesia and were administered single antiplatelet drug 5 days before the procedure and double antiplatelet therapy for 3 months afterwards. Fifteen of the patients were asymptomatic, eight had headache, thirteen patients presented symptoms due to mass effect of the aneurysm on CNS structures, twelve were treated due to a post-surgical relapse and one patient presented relapsing TIAs due to distal embolization from the aneurysm dome. Choice of FD treatment was done according to aneurysm anatomy (fusiform over saccular, dome/neck ratio < 2) and whenever conventional treatment (coil embolization) appeared difficult (eg. Large aneurysm neck, fusiform aneurysms or difficult sac catheterization). We considered a dome/neck ratio > 2 as the only exclusion criteria. RESULTS: Successful stent deployment was achieved in 50 procedures out of 52 (94.34%) while overall mortality was 2% (1/49). Forty-eight patients were evaluated at long-term follow-up for a total of 56 treated aneurysms. At 3 months, follow-up 75% (42/56) of the aneurysms were excluded from intracranial circulation, at 6 months 80.35% (45/56) and at 12 months 84% (47/56). Stent patency was observed in 100% of patients at short and long-term follow-up, with only two cases of intimal hyperplasia at 3 months, without any further complications. CONCLUSIONS: According to our study FD repair of unruptured intracranial aneurysms appeared to be a safe and effective technique, especially in selected patients with hostile anatomy for traditional embolization.

Flow diverter treatment of cerebral blister aneurysms.

PURPOSE: Blood blister-like aneurysms (BBA) are small, friable, broad-based aneurysms that represent high risk for rerupture. Treatment of BBA is challenging, and may include surgical wrapping, clipping, multiple overlapping stents, and/or coiling. Flow diversion is a rapidly evolving treatment strategy for intracranial aneurysms, but the evidence for its use in cases of BBA is scarce. METHODS: A retrospective review of flow-diverter-treated, ruptured BBA cases at our tertiary care institution was undertaken. Clinical, imaging, procedural, and mid-term follow-up data on the patients were collected. RESULTS: Eight patients underwent flow-diverter stent treatment for ruptured BBA. Median age at time of treatment was 49 years (interquartile range [IQR] 42-57) with five females (62.5%). The most common location of the BBA was the supraclinoid segment of the internal carotid artery. The median Hunt-Hess score was 2 (IQR 1.7-3.2). All patients were treated with dual anti-platelet therapy. Good clinical outcomes (modified Rankin score 0-2) were seen in 6/7 (85.7%) patients with available follow-up at 1 year. Complete occlusion of the aneurysm on latest angiogram (7) or MRI (1) was seen in 6/8 (75%) patients (at a median of 8 months). No patient had rerupture, retreatment, or recurrence of the aneurysm. CONCLUSION: Flow-diverter stents may be a feasible treatment option for BBAs. They offer high occlusion and low retreatment rates with good mid-term outcomes, but the long-term efficacy remains unknown. Also, dual anti-platelet therapy in the acute ruptured setting can be challenging.

Clipping in Awake Surgery as End-Stage in a Complex Internal Carotid Artery Aneurysm After Failure of Multimodal Endovascular and Extracranial-Intracranial Bypass Treatment.

BACKGROUND: Intracranial carotid artery aneurysm can be treated via microsurgical or endovascular techniques. The optimal planning is the result of the careful patient selection through clinical, anatomic, and angiographic analysis. CLINICAL PRESENTATION: We present a case of ruptured internal carotid artery (ICA) aneurysm that became a complex aneurysm after failure of multi-endovascular and surgery treatment. We describe complete trapping in awake craniotomy after failure of coiling, stenting, and bypassing. CONCLUSIONS: ICA aneurysms could become complex aneurysms following multi-treatment failure. Endovascular approaches to treat ICA aneurysms include coiling, stenting, flow diverter stenting, and stenting-assisted coiling technique. The role of surgery remains relevant. To avoid severe neurologic deficits, recurrence, and the need of retreatment, a multidisciplinary discussion with experienced endovascular and vascular neurosurgeons is mandatory in such complex cases.

Neurological outcomes of flow-diverter stent placement for middle cerebral artery aneurysms, with reference to the effects of argatroban on ischemic events: patient series.

BACKGROUND: A systematic review and meta-analysis of flow-diverter stents (FDSs) for the treatment of middle cerebral artery (MCA) aneurysms reported concerns about ischemic complications during treatment. The authors report on the intraoperative and postoperative complications of unruptured MCA aneurysms and their control strategies at their hospital, with detailed information on the aneurysms and a review of the previous literature. OBSERVATIONS: Intraoperative and perioperative in-stent thrombus occlusion occurred in 3 (37.5%) of the 8 patients evaluated. In cases with in-stent thrombus formation, rapid administration of 10 mg argatroban led to improvement in blood flow, as seen on angiography. Only 1 patient (12.5%) had a symptomatic stroke postoperatively. This patient was admitted for rehabilitation and drug therapy but was discharged from the hospital 10 days postoperatively with a modified Rankin Scale (mRS) score of 1. The patient had an mRS score of 0 at 90 days after surgery and at the last observation. LESSONS: Ischemic complications require attention during FDS treatment for MCA aneurysms. The use of argatroban in cases of in-stent thrombosis may contribute to a good neurological prognosis. https://thejns.org/doi/10.3171/CASE24237.

Hemidystonia-hemiatrophy syndrome following placement of internal carotid artery flow diverter stent.

We report hemidystonia and cerebral hemiatrophy in a 39-year old woman beginning three months after placement of an internal carotid artery flow diverting stent for supraclinoid aneurysm, complicated by early post-procedural stroke. We highlight the unusual demographics and short latency to onset, as well as the occurrence of striatal mineralisation, which may reflect ongoing neurodegeneration, but has also been suggested to contribute to oxidative neuronal injury. The late age of the inciting cerebral insult and of onset of the movement disorder, temporal course, and relation to endovascular intervention serve to expand the spectrum of this unusual condition.

Management of ruptured aneurysmal subarachnoid hemorrhage with multiple basilar trunk aneurysms using a flow-diverter stent: A case report.

Ruptured aneurysmal subarachnoid hemorrhage associated with multiple basilar trunk aneurysms represents a rare clinical condition. Endovascular intervention stands as the preferred therapeutic approach. We present the case of a 35-year-old patient with subarachnoid hemorrhage and three consecutive basilar trunk aneurysms. Utilizing a flow-diverter stent, we achieved simultaneous occlusion of all 3 aneurysms, performed 2 hours post dual antiplatelet therapy (comprising salicylic acid 300 mg and ticagrelor 180 mg). Sustained resistance to clopidogrel necessitated the subsequent 3 months, followed by single antiplatelet therapy. At the 1-month follow-up, the patient demonstrated a favorable clinical course, devoid of cerebral infarction, and evidenced unobstructed stent patency upon brain magnetic resonance imaging.