Endovascular Management Research Articles

Directed work-up of select penetrating neck injuries is safe: Hard signs continue to soften

IntroductionManagement of penetrating neck injuries (PNIs) has evolved over time, more frequently relying on increased utilization of diagnostic imaging studies. Directed work-up with computed tomography imaging has resulted in increased use of angiography and decreased operative interventions. We sought to evaluate management strategies after directed work-up, hypothesizing increased use of non-operative therapeutic interventions and lower mortality after directed work-up. MethodsPatients with PNI from 2017 to 2022 were identified from a single-center trauma registry. Demographics, injuries, physical exam findings, diagnostic studies and interventions were collected. Patients were stratified by presence of hard signs and management strategy [directed work-up (DW) and immediate operative intervention (OR)] and compared. Outcomes included therapeutic non-operative intervention [endovascular stent, embolization, dual antiplatelet therapy (DAPT), or anticoagulation (AC)], non-therapeutic neck exploration, length of stay (LOS), and mortality. ResultsOf 436 patients with PNI, 143 (33%) patients had vascular and/or aerodigestive injuries. Of these, 115 (80%) patients underwent DW and 28 (20%) patients underwent OR. There were no differences in demographics or injury severity score between groups. Patients in the DW group were more likely to undergo vascular stent or embolization (p = 0.040) and had fewer non-therapeutic neck explorations (p = 0.0009), compared to the OR group. There were no differences in post-intervention stroke, leak, or mortality. Sixty percent of patients with vascular hard signs and 78% of patients with aerodigestive hard signs underwent DW. ConclusionsDirected work-up in select patients with PNI is associated with fewer non-therapeutic neck explorations. There was no difference in mortality. Selective use of endovascular management, AC and DAPT is safe.

Glue embolization of ruptured pseudoaneurysm secondary to reversible cerebral vasoconstriction syndrome: An illustrative case.

Reversible cerebral vasoconstriction syndrome (RCVS) is an increasingly recognized condition characterized by thunderclap headache with or without other neurological deficits and diffuse vasoconstriction of cerebral arteries. Altered cerebrovascular tone may produce hemorrhage or stroke. A retrospective review of patients with RCVS at our institution (2000-2023) yielded one case of pseudoaneurysm secondary to RCVS. Diagnostic cerebral angiogram demonstrated diffuse multifocal segmental narrowing consistent with RCVS and a left M4 pseudoaneurysm in proximity to the cortical hemorrhage. The pseudoaneurysm was treated with branch vessel sacrifice using nBCA glue in a 1 : 3 ratio with ethiodized oil. After securing the source of hemorrhage, the patient received an intra-arterial infusion of Verapamil. This unique presentation of pseudoaneurysm secondary to RCVS in this patient highlights the impact of hemodynamic alteration as a possible source of bleeding and demonstrates a potential management strategy. Endovascular management with nBCA glue embolization successfully treated this lesion.

3D impression to facilitate in situ surgical renal segmental artery aneurysm repair: A novel open approach option for an unusual vascular condition.

Renal Artery Aneurysms (RAA) affect approximately 0.01%-0.97% of the population. Early diagnosis, thorough 3D-preoperative planning, and timely surgical treatment may offer effective and safe management. We report the open reparation of a segmental renal artery saccular aneurysm close to the bifurcation with detailed preoperative planning based on 3D printing, and with successful postoperative results. We report the case of a 36-year-old man with a 3.5 × 5cm segmental renal artery saccular aneurysm close to the bifurcation, for which endovascular management was ruled out and open management was chosen with detailed preoperative planning based on 3D printing and with successful postoperative results. When an open approach is chosen in the RAA treatment, a detailed study of the anatomical configuration of the RAAs is mandatory, and life-size 3D printing is a valuable tool that could contribute to the operative technique, reduce surgical times associated with renal ischemia and provide minute details that would make a clear anatomical difference during in situ repair.

Endovascular and percutaneous embolization of a giant post traumatic arteriovenous fistula of inferior epigastric vessels

BackgroundArteriovenous fistulas involving the anterior abdominal wall can result from trauma. Such fistulas may remain asymptomatic and undetected for a prolonged duration of time. They tend to recruit multiple arterial feeders with remodelling in the feeding arteries, making them challenging to treat.Case presentationWe discuss a rare case of a 60-year-old male who presented with complaints of a progressive painless swelling in right lower abdomen. There was a history of blunt injury to abdomen at the same site during alleged road traffic accident 3 years ago. On CT angiography, an arteriovenous fistula was localised to the anterior abdominal wall arising predominantly from the right inferior epigastric artery with a giant venous sac and terminating as a tortuous single venous channel into the right external iliac vein. Few other small feeders were also seen arising from branches of right superior epigastric artery along Winslow’s pathway. The main challenge in endovascular management of this patient was embolization of a high flow shunt with a large venous sac and multiple arterial feeders. The dominant arterial feeder was embolized using vascular plug. The superficial location of the lesion offered an additional percutaneous window besides endovascular approach. The venous sac was percutaneously accessed and embolized using n-butyl cyanoacrylate after balloon occlusion of outflow vein. On follow up ultrasonographic evaluation at 3 months, near complete thrombosis of the venous sac was achieved.ConclusionsTraumatic arteriovenous fistulas involving the inferior epigastric vessels are rare clinical entities. CT angiogram and digital subtraction angiography help in the optimal diagnosis and treatment planning. The use of mechanical embolization devices to cause flow arrest offers an opportunity to use liquid embolic agents which offer better percolation within the lesion. Interventional radiology offers an ideal management of these complex high flow fistulas with a good technical success and acceptable safety profile.

Factors affecting resolution of oculomotor nerve palsy following endovascular embolization of posterior communicating artery aneurysms

PurposeTo investigate the effect of endovascular embolization of posterior communicating artery (Pcom) aneurysms on concomitant oculomotor nerve palsy (OMNP) and factors affecting the effect of treatment. Materials and methodsPatients with the Pcom aneurysms concomitant with OMNP were retrospectively enrolled for endovascular treatment of the aneurysms. All patients had the endovascular management. The clinical effect, degree of OMNP, size of the aneurysm, type of treatment, subarachnoid hemorrhage (SAH), and time from onset to treatment were analyzed on the resolution of OMNP. ResultsNinety-six patients with 99 Pcom aneurysms were enrolled and treated endovascularly, with the success rate of 100%. Immediately after endovascular treatment, 75 aneurysms (75.75%) got complete occlusion, and 24 (24.24%) nearly complete occlusion. Followed up for 3–18 (mean 8.52±0.56) months, complete resolution of the OMNP was achieved in 63 patients (65.63%), partial resolution in 21 (21.88%), and non-recovery in the other 12 (12.50%). The degree of OMNP at onset, SAH, and time from onset to treatment were significantly (P<0.05) correlated with the resolution of OMNP. Univariate analysis revealed that younger age of the patient, degree of OMNP at onset, presence of subarachnoid hemorrhage, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. Multivariate analysis revealed that the younger age, degree of OMNP at onset, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. ConclusionEndovascular embolization of Pcom aneurysms concomitant with OMNP can effectively improve the OMNP symptoms, especially for patients with moderate and a shorter history of OMNP. Younger age, degree of oculomotor nerve palsy at onset, and time from onset to treatment may significantly affect recovery of oculomotor nerve palsy.

Bailout utilization of tirofiban for distal embolization/acute thrombosis during endovascular management in occlusive PAD patients

Bailout utilization of tirofiban for distal embolization/acute thrombosis during endovascular management in occlusive PAD patients

Subtemporal Approach for the Treatment of Ruptured and Unruptured Distal Basilar Artery Aneurysms: Is There a Contemporary Use?

Distal basilar artery aneurysms (DBAs) are high-risk lesions for which endovascular treatment is preferred because of their deep location, yet indications for open clipping nonetheless remain. The subtemporal approach allows for early proximal control and direct visualization of critical posterior perforating arteries, especially for posterior-projecting aneurysms. Our objective was to describe our clinical experience with the subtemporal approach for clipping DBAs in the evolving endovascular era. This was a retrospective, single-institution case series of patients with DBAs treated with microsurgery over a 21-year period (2002-2023). Demographic, clinical, and surgical data were collected for analysis. Twenty-seven patients underwent clipping of 11 ruptured and 16 unruptured DBAs with a subtemporal approach (24 female; mean age 53 years). Ten patients had expanded craniotomies for treatment of additional aneurysms. The aneurysm occlusion rate was 100%. Good neurological outcomes as defined by the modified Rankin Scale score ≤2 and Glasgow Outcome Scale score ≥4 were achieved in 21/27 patients (78%). Two patients died before hospital discharge, one from vasospasm-induced strokes and another from an intraoperative myocardial infarction. These results demonstrate that microsurgical clip ligation of DBAs using the subtemporal approach remains a viable option for complex lesions not amenable to endovascular management.

Endovascular Management of Vertebroplasty Cement Embolism: Case Report and Review of Literature

Endovascular Management of Vertebroplasty Cement Embolism: Case Report and Review of Literature

Endovascular Management of Chronic Limb-Threatening Ischemia (CLTI) in the Elderly: A Focus on Frailty, Wound Healing, and Outcomes

In India, a significant scarcity of published data exists regarding chronic limb-threatening ischemia (CLTI) and its management, especially among the elderly population. CLTI, often accompanied by frailty poses a significant healthcare challenge. While endovascular interventions offer hope, there remains a dearth of outcome data for this age group. This study seeks to address this critical gap by investigating the impact of frailty on outcomes, emphasizing amputation-free survival (AFS), wound healing, and health-related quality of life (HRQoL). Our study included 131 elderly CLTI patients aged ≥70 years who underwent infrainguinal endovascular interventions between April 2018 and August 2021, with a follow-up period of 2 years. Among the patients, 93.9% had diabetes mellitus and 82.4% had hypertension. Clinical frailty was assessed using the Clinical Frailty Scale (CFS). Patients were categorized into Group 1 (CFS 1-5) and Group 2 (CFS 6-9). Primary outcomes were AFS, wound healing, HRQoL, and their association with frailty. Secondary outcomes included technical success, procedure-related complications, major adverse limb events (MALE), major adverse cardiovascular events (MACE), vessel patency, re-intervention rates, and mortality rates including peri-procedural and overall mortality. Technical success was achieved in 86.3% of patients, with frailty significantly influencing this outcome. Group 2 exhibited reduced technical success (80.8%) compared to Group 1 (93.1%). The major amputation rate was 9.2%, with higher rates in Group 2 [univariate Hazard Ratio (HR): 5.20; p=0.033]. Similarly, Group 2 showed elevated overall mortality [univariate HR: 5.18; p < 0.001]. AFS at 1 and 2 years were 67.9% and 55% respectively, with higher rates in Group 1. Wound healing was achieved in 76.1% of patients (83/109), with frailty significantly associated with delayed wound healing (p < 0.001). Vessel patency at 1 year was observed in 88.8% of patients. HRQoL significantly improved post-intervention, with VascuQol-6 scores increasing from an average of 9 of 24 at baseline to 20 of 24 at 2 years. Frailty score significantly correlated with VascuQol-6 scores at 1 and 2 years (p < 0.0012). Group 1 exhibited higher VascuQol-6 scores compared to Group 2, indicating improved HRQoL during follow-up. Successful endovascular treatments in high-risk CLTI patients promote improved wound healing and post-treatment quality of life (QoL). Frailty should be assessed before endovascular interventions as it correlates with adverse outcomes, including amputations and mortality. While revascularization holds promise, caution is advised for frailer patients, emphasizing the importance of personalized care and tailored treatments for elderly CLTI patients.

Metallic Artifice Reduction Angio Tomography versus Digital Subtraction Angiography for the Evaluation of Occlusion of Intracranial Aneurysms after Endovascular Management

Objective: To compare the accuracy of metallic artifice reduction Angiotomography (CTAMaR) and digital subtraction angiography (DSA) for the evaluation of occlusion of intracranial aneurysms after endovascular management with coils.

Transarterial Embolization of Intracranial Dural Arteriovenous Fistulas Cognard Type V With Direct Drainage Into the Perimedullary Veins: Case Report and Literature Review.

Cognard type V fistula (CVF) is a rare type of dural arteriovenous fistula characterized by spinal perimedullary venous drainage. Owing to the lack of pathognomonic findings, misdiagnosis is common. Patients often undergo multiple spinal angiograms negative for spinal vascular malformations. Digital subtraction angiography is the gold standard diagnostic tool. The preferred treatment option is endovascular management with embolization through a transarterial, transvenous, or combined approach. Other options include open surgery, stereotactic radiosurgery, or a combination of both. The patient from case # 1 presented with progressive weakness and hypoesthesia in the bilateral lower extremities, with urinary and bowel incontinence. The DSA identified a CVF fed by the meningohypophyseal trunk and a draining perimedullary vein. Embolization with 0.1 ccs of Onyx-18 was performed with complete fistula occlusion. The patient from case # 2 developed bilateral lower extremity weakness, diffuse numbness, and urinary incontinence. The DSA showed a CVF fed by tributaries from the ascending pharyngeal artery and posterior meningeal artery branches of the V3 segment, draining into a perimedullary vein. Embolization with 0.3 cc of Onyx-18 was performed with 100% occlusion of the fistula. A 1-year follow-up angiogram confirmed complete fistula occlusion. Both patients consented to the procedure. Even if a patient only presents symptoms of myelopathy, CVF should be considered. Herein, we present 2 cases of CVF with direct drainage into the perimedullary veins which presented exclusively with myelopathy syndrome and describe treatment with trasarterial embolization with Onyx.

Angiographic evidence of an inadvertent cannulation of the marginal sinus following central line migration: illustrative case.

Central venous catheters (CVCs) play an indispensable role in clinical practice. Catheter malposition and tip migration can lead to severe complications. The authors present a case illustrating the endovascular management of inadvertent marginal sinus cannulation after an internal jugular vein (IJV) catheter tip migration. A triple-lumen CVC was inserted without complications into the right IJV of a patient undergoing a repeat sternotomy for aortic valve replacement. Two weeks postinsertion, it was discovered that the tip had migrated superiorly, terminating below the torcula in the posterior fossa. In the interventional suite, a three-dimensional venogram confirmed the inadvertent marginal sinus cannulation. The catheter was carefully retracted to the sigmoid sinus to preserve the option of catheter exchange if embolization became necessary. After a subsequent venogram, which displayed an absence of contrast extravasation, the entire catheter was safely removed. The patient tolerated the procedure well. Clinicians must be vigilant of catheter tip migration and malposition risks. Relying solely on postinsertion radiographs is insufficient. Once identified, prompt management of the malpositioned catheter is paramount in reducing morbidity and mortality and improving patient outcomes. Removing a malpositioned catheter constitutes a critical step, best performed by a specialized team under angiographic visualization.

Initial experience of endovascular aneurysm repair at the Dr. Eduardo Liceaga General Hospital of Mexico

Background: Abdominal aortic aneurysm (AAA) is the permanent and irreversible dilation of the lower part of the aorta where the vessel expands, making it susceptible to rupture, which represents a high mortality incident. Methods: A review of clinical records was carried out from September 2021 to March 2023, patients who were diagnosed with aortic aneurysm were included in whom endovascular exclusion of abdominal and thoracic aortic aneurysm was performed at the General Hospital of Mexico by the angiology vascular and endovascular surgery department. Results: 18 endovascular repairs of aortic aneurysms were performed, of which 15.4% were female (n=6) and 84.6% male (n=12). The average proximal neck diameter in the thoracic aorta was 31 mm, average proximal neck diameter in infrarenal AAA 22.2 mm, average aneurysmal diameter in infrarenal segment 63.8 mm, thoracic 31 mm. Regarding the type of endovascular procedure, 11.1% were repaired with the fenestrated endovascular aneurysm repair (FEVAR) technique, and the same proportion with chimney endovascular aneurysm repair (ChEVAR), for a resolution with conventional EVAR of 77.7%. Complications occurred in 3 patients, 2 of which resulted in type 1a and 1b endoleaks that were reoperated and repaired with a proximal cuff, balloon angioplasty, and embolization of the aneurysmal sac with coils. Conclusions: Aortic aneurysm remains a major cause of death in adults because of aortic rupture despite advances over the past two decades that have been made in the endovascular management of large, symptomatic, and ruptured. Timely treatment is essential to prevent rupture and poor patient outcomes.

Pseudoaneurysm formation following transarterial embolization of traumatic carotid-cavernous fistula with detachable balloon: An institutional cohort long-term study.

The goal of therapy for traumatic carotid-cavernous fistula (TCCF) is the elimination of fistula while maintaining patency of the parent artery. The treatment for TCCF has evolved from surgery to endovascular management using detachable balloons, coils, liquid embolic agents, covered stents, or flow-diverter stent through arterial or venous approaches. Despite the withdrawal of detachable balloons from the market in the United States since 2004, transarterial embolization with detachable balloons has currently remained the best initial treatment for TCCF in several countries. However, the pseudoaneurysm formation following transarterial detachable balloon embolization has rarely been observed in long-term follow-up. To determine the occurrence and long-term follow-up of pseudoaneurysm after transarterial detachable balloon for TCCF. Between January 2009 and December 2019, 79 patients diagnosed with TCCF were treated using detachable latex balloons (GOLDBAL) of four sizes. Pseudoaneurysm sizes were stratified into five grades for analysis. Initial and follow-up assessments involved computed tomography angiography at 1 month, 6 month, 1 year, and longer intervals for significant cases. Clinical follow-ups occurred semi-annually for 2 years, then annually. Factors analyzed included sex, age, fistula size and location, and balloon size. In our cohort of 79 patients treated for TCCF, pseudoaneurysms formed in 67.1%, with classifications ranging from grade 0 to grade 3; no grade 4 or giant pseudoaneurysms were observed. The majority of pseudoaneurysms did not progress in size, and some regressed spontaneously. Calcifications developed in most large pseudoaneurysms over 5-10 years. Parent artery occlusion occurred in 7.6% and recurrent fistulas in 16.5%. The primary risk factors for pseudoaneurysm formation were identified as the use of specific balloon sizes, with balloon SP and No. 6 significantly associated with its occurrence (P = 0.005 and P = 0.002, respectively), whereas sex, age, fistula size, location, and the number of balloons used were not significant predictors. Pseudoaneurysm formation following detachable balloon embolization for TCCF is common, primarily influenced by the size of the balloon used. Despite this, all patients with pseudoaneurysms remained asymptomatic during long-term follow-up.

The role of surgical disconnection for posterior fossa pial arteriovenous fistulas and dural fistulas with pial supply: an illustrative case series.

Pial arteriovenous fistulas (pAVFs) are rare vascular malformations characterized by high-flow arteriovenous shunting involving a cortical arterial supply directly connecting to venous drainage without an intermediate nidus. Dural arteriovenous fistulas (dAVFs) can infrequently involve additional pial feeders which can introduce higher flow shunting and increase the associated treatment risk. In the posterior fossa, arteriovenous fistula (AVF) angioarchitecture tends to be particularly complex, involving either multiple arterial feeders-sometimes from both dural and pial origins-or small caliber vessels that are difficult to catheterize and tend to be intimately involved with functionally critical brainstem or upper cervical cord structures. Given their rarity, published experience on microsurgical or endovascular treatment strategies for posterior fossa pAVFs and dAVFs with pial supply remains limited. Retrospective chart review from 2019-2023 at a high-volume center identified six adult patients with posterior fossa pAVFs that were unable to be fully treated endovascularly and required microsurgical disconnection. These cases are individually presented with a technical emphasis andsupported by comprehensive angiographic and intraoperative images. One vermian (Case 1), three cerebellopontine angle (Cases 2-4) and two craniovertebral junction (Cases 5-6) posterior fossa pAVFs or dAVFs with pial supply are presented. Three cases involved mixed dural and pial arterial supply (Cases 1, 4, and 6), and one case involved a concomitant microAVM (Case 2). Endovascular embolization was attempted in four cases (Cases 1-4): The small caliber and tortuosity of the main arterial feeder prevented catheterization in two cases (Cases 1 and 3). Partial embolization was achieved in Cases 2 and 4. In Cases 5 and 6, involvement of the lateral spinal artery or anterior spinal artery created a prohibitive risk forendovascular embolization, and surgical clip ligation was pursued as primary management. In all cases, microsurgical disconnection resulted in complete fistula obliteration without evidence of recurrence on follow-up imaging (mean follow-up 27.1 months). Two patients experienced persistent post-treatment sensory deficits without significant functional limitation. This illustrative case series highlights thetechnical difficulties and anatomical limitations of endovascular management for posterior fossa pAVFs and dAVFs with pial supply and emphasizes the relative safety and utility of microsurgical disconnection in this context. A combined approach involving partial preoperative embolization-when the angioarchitecture is permissive-can potentially decrease surgical morbidity. Larger studies are warranted to better define the role for multimodal intervention and to assess associated long-term AVF obliteration rates in the setting of pial arterial involvement.

High-frequency optical coherence tomography for endovascular management of cerebral aneurysms.

Endovascular management of intracranial aneurysms has become the mainstay of treatment in recent years; however, retreatment rates remain as high as 1 in 5. High-frequency optical coherence tomography (HF-OCT) is an emerging imaging modality for the assessment, treatment and follow-up of cerebral aneurysms. EMBASE and SCOPUS databases were searched for studies relating to the management of intracranial aneurysm with OCT. A combination of keywords were used including 'cerebral aneurysm', 'intracranial aneurysm', 'high-frequency optical coherence tomography', 'optical coherence tomography', and 'optical frequency domain imaging'. There were 23 papers included in this review. For the assessment of intracranial aneurysm, OCT was able to accurately assess aneurysm morphology as well as detailed analysis of arterial wall layers. During IA treatment, OCT was used to assess and troubleshoot stent placement to optimise successful isolation from the circulation. In the follow-up period, endothelial growth patterns were visualised by OCT imaging. OCT shows promise for the treatment of IAs at all stages of management. Due to the novel development of HF-OCT, there is limited longitudinal data in human studies. Further research in this area is required with a focus specifically on long-term treatment outcomes in humans.

Type I Endoleak Following Covered Stent Graft Placement for Traumatic Subclavian Artery Pseudoaneurysm

AbstractSubclavian artery pseudoaneurysm is an uncommon entity caused by trauma or iatrogenic arterial injury. Endovascular management is the preferred treatment strategy but can be complicated by endoleaks. We report a case of type I endoleak occurring after endovascular covered stent placement to treat a traumatic pseudoaneurysm of proximal left subclavian artery.

Addressing the Impact of Deep Venous Stenting on the Management of Venous Ulcer

IntroductionVenous ulcers are a late and severe form of CVI and account for 70% of all etiologies that cause leg ulcers in the lower limb and they account for 20% of the 2.5 million cases complaining of chronic venous disease. Our study aims to investigate the effect of venous stenting of the deep veins on the healing of the venous ulcer. MethodsThis is a single-center, retrospective study conducted on prospectively recorded medical records of 78 patients with chronic deep venous diseases – C6 (either non-occlusive iliac venous lesion or post-thrombotic syndrome). Our lesion involved May-Thurner lesions, occlusions, insufficiencies, or stenoses owing to an affection of the venous outflow segment. All our patients underwent endovascular management, and those who did not respond successfully were transitioned to compression therapy. We then compared the outcomes of both groups in terms of ulcer healing and quality of life. ResultsA total of 78 patients (78 limbs), with a mean age of 39.6 ± 8.06 (range; 22-60) years, were treated. 54 patients (67.9%) were males, and 24 (32.1%) were female. The etiology was primary non-occlusive iliac venous lesion (NIVL) in 12 limbs (16.2%) and secondary (post-thrombotic) PTS in 66 (83.7%). Follow-up of the ulcer with compliance to compression therapy and standard care of the ulcer, sustained ulcer healing (reduction in ulcer area) was achieved in 60% of limbs, and most of non-occlusive the healing occurred within the first 3 months (p<0.01) ConclusionsOur results show that deep venous stenting is associated with high wound healing rates. This rate reaches a statistically significant difference in 3 months but this difference doesn't reach statistical significance at six months, with less recurrence, and improved quality of life with a high cumulative patency rate and that compression therapy is the mainstay of the conservative management of venous ulceration.

The Management of Aneurysmal Degeneration of Lower Extremity Cryopreserved Saphenous Vein Bypass Grafts

Objective/BackgroundThe use of cryopreserved saphenous veins (CSVs) for the treatment of lower extremity peripheral arterial disease is an attractive option when there is no available autogenous vein. Prior studies found CSVs are at risk for aneurysmal degeneration requiring reoperation. As the management of these complications and patient outcomes is not well described, the objective of this case series is to describe the open and endovascular management of degenerative CSVs at a tertiary community center. MethodsAll CSVs implanted for lower extremity bypass at our institution between 2001 and 2021 were retrospectively reviewed. All CSVs with evidence of aneurysmal change were included in this study. CSVs with evidence of active infection were excluded. The decision to intervene was left to the discretion of the operating surgeon. Demographic data, indications for the index operation, and details about subsequent interventions for degenerative CSVs were recorded. Study endpoints included limb salvage and continued patency. Demographic data, indications for the index operation, and details about subsequent interventions for degenerative CSVs were recorded. ResultsSeventeen bypasses were identified to have aneurysmal degeneration in thirteen patients in the absence of infection between 2001 and 2021. Nine of the thirteen patients were male, and the average age and BMI during the index procedure were 72 and 28 respectively. Indications for the index bypass included acute limb ischemia (ALI) (9), popliteal aneurysm (2), and CLTI with Rutherford's class IV (5) and V (1).The mean time between the index procedure and first graft revision due to aneurysmal changes was 4 years. Most of the aneurysms did not occur at the site of anastomosis with 13 occurring in the body of the graft. Thirteen grafts were managed with open surgery and three were managed with endovascular techniques. All endovascular repairs were managed via covered stenting.Patients were followed for an average duration of 7 years from the initial bypass and 2 years from their last aneurysmal repair. Limb salvage in this cohort was 87% with 2 limbs requiring amputation, all of whom underwent open reconstruction. The mortality rate in this series was 54% and no patients died due to complications from their graft. Continued patency on Kaplan Meier survival curve analysis was 79% at 6 months, 65% at one year, 54% at three years, and 27% at 5 years. ConclusionIn our experience, aneurysmal degeneration of CSV grafts were mostly managed with standard open surgical techniques, although endovascular therapy also proved acceptable. Limb salvage rates and continued patency of repair at one year in this cohort were acceptable. This case series highlights the importance of diligent surveillance for patients with CSVs.

158 Preclinical Direct Endoluminal Assessment of Endothelialization After Flow Diversion With Microangioscopy

INTRODUCTION: Endoluminal imaging (ELI) is an emerging adjunct in endovascular cerebral aneurysm management. Indirect ELI, as with optical coherence tomography, may be useful in detecting malapposition after flow diversion (FD). Direct ELI technologies, such as with our previous described microangioscope, have been shown to be able to delineate between different thrombi and visualize neoepithelialization after stent placement with high resolution. METHODS: In a rabbit model we implanted each left common carotid artery (CCA) with a shielded FD (Medtronic Pipeline Vantage) and non-shielded FD (Medtronic Pipeline Flex) in the right CCA. We studied 9 animals in 3 groups: 1) no periprocedural antiplatelet therapy, 2) aspirin 81 mg daily, 3) aspirin 81 mg and clopidogrel 75 mg daily. FD thrombosis, stenosis, malapposition, and neoepithelialization were all evaluated by diagnostic cerebral angiography (DSA) and microangioscopy after 30 days. DSA and angioscopic video were analyzed by independent evaluators and compared with histopathologic analysis. RESULTS: In the aspirin and DAPT groups, there were no significant observed differences in stent thrombosis, stenosis, malapposition, or neoepithelialization between the shielded and non-shielded FDs in each rabbit as measured by histologic analysis. There was significantly more thrombus formation in Group 1. Neointimal thickness as measured by the microangioscope was highly correlated with histology (r = 0.72, p = 0.016). Inter-rater agreement of microangioscope videos was highest for FD thrombosis and stenosis. CONCLUSIONS: There were no significant differences between in-stent thrombosis, stenosis, malapposition, or neopithelialization between shielded and non-shielded FDs. Microangioscopy measurements for neointimal thickness were highly correlated with pathology, and thus may be a helpful adjunct to DSA in FD follow-up.