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Ringer, Andrew J.

https://orcid.org/0000-0002-2524-3426

Mayo Clinic

University of Cincinnati

Citations 29

Abstract 290: Treatment Strategies for Residual and Recurrent Aneurysms After Woven EndoBridge Therapy: A Multicenter Propensity‐Matched Analysis
Gudino, Andres, Reddi, Preethi , Sridhar, V., Haranhalli, Neil , Karandish, Alireza , Aghaebrahim, Amin, Sauvageau, Eric , Crowley, W F, Dabus, Guilherme , Paul, A.R. , Puri, A, Rinaldo, Lorenzo , Brinjikji, Waleed , Goren, Oded , Siddiqui, Adnan, Jaikumar, Vinay , Essibayi, Muhammed Amir , Gutierrez‐Aguirre, Salvador F. , Hendrix, Philipp , Ransom, Ryan C. , Gudino, Andres , Ringer, Andrew J. , Kühn, Anna Luisa , Field, N., Ríos-Zermeño, Jorge , Amllay, Abdelaziz , Monteiro, Andre , Khatri, Deepak , Toledo, Otavio F. De , Crowley, W., Dabus, Guilherme C. , Matouk, Charles , Tawk, Rabih G. , Paul, A. R., Mocco, J , Majidi, Shahram , Samaniego, Edgar A , Lanzino, Giuseppe , Hanel, Ricardó A. , Altschul, David , Levy, Elad I.

Stroke: Vascular and Interventional Neurology | December 2, 2025 | Volume: 5 | Issue: S1 | Pages: No page available

10.1161/svi270000_290 Get It

Introduction Post‐market and multicenter studies report low complete occlusion rates (41‐49%) and higher retreatment rates (13%) following WEB deployment, compared to 3.8% with microsurgical clipping. While retreatment after WEB has been shown to be technically feasible, data on final angiographic outcomes remain limited. We performed a retrospective analysis of prospective databases from 14 cerebrovascular centers in the US to compare the safety and efficacy of retreatment versus continued observation for residual and recurrent aneurysms after initial WEB deployment. Materials/Methods Multinomial logistic regression was used to identify baseline characteristics of untreated and residual/recurrent aneurysms that may act as confounders, which then underwent propensity scored matching (PSM). Results Among 211 patients (125 observed, 86 retreated), retreatment was more common in initially ruptured aneurysms (p<0.001), which showed higher recurrence (p=0.036) and sac‐dominant residuals (p=0.004). These were primarily due to WEB compression on follow‐up (p=0.001), rather than incomplete occlusion with an appropriately sized device (p<0.001). Retreatment was associated with significantly higher rates of complete angiographic occlusion at last follow‐up compared to observation alone (p<0.001), a finding that remained consistent across subgroups defined by initial unruptured status, residual type, and recurrence patterns (all p<0.05). Clipping demonstrated higher, though statistically insignificant, rates of complete occlusion; flow diversion and stent‐assisted coil embolization yielded comparable complete occlusion rates at follow‐up. After propensity score matching, retreatment remained significantly associated with higher rates of complete angiographic occlusion (all p<0.05), with comparable outcomes observed between clipping and various endovascular approaches as above. Conclusion Retreatment improved complete occlusion rates; however, no aneurysmal hemorrhages occurred in either group. Further intervention may be unnecessary when the WEB device—whether compressed or intact (BOSS 0/1)—adequately protects the dome. In cases where WEB compression significantly exposes the aneurysm wall, stent‐assisted coiling or flow diversion can be performed safely and successfully, depending on vascular anatomy and surgeon preference. image image
E-059 Influence of race on extended length of stay following mechanical thrombectomy for anterior circulation stroke
Koo, A, Johnson, Scott, Starke, R, Welch, Babu G. , Rivet, Dennis J. , Graffeo, Christopher S. , Klopfenstein, Jeffrey D., Sahlein, D, Eshraghi, Sheila, Altschul, D, Alaraj, A, Davies, Jason M., Raper, D, Park, M , Malek, Adel M. , Monteith, Stephen J., Eckardt, Glenn S., Beaty, N, Schirmer, C, Arthur, A, Wolfe, S, Chen, C, Church, E, Dornbos, D, Chu, T, Johnson, S, Starke, R, Altschul, David , Ringer, Andrew J. , Hoh, Brian L. , Alaraj, Ali , Mocco, J , Grande, Andrew Walker , Eckardt, G, Beaty, Narlin Bennet , Schirmer, Clemens M., Arthur, A, Dornbos, David

SNIS 22nd annual meeting electronic poster abstracts | July 14, 2025 | Volume: No volume available | Issue: No issue available | Pages: A132.1-A132

10.1136/jnis-2025-snis.175 Get It

Impact of duration of dual anti-platelet therapy on risk of complications after stent-assisted coiling of unruptured aneurysms
Ringer, Andrew J. , Hanel, Ricardó A. , Baig, Ammad A. , Siddiqui, Adnan H. , Lopes, Demetrius K. , Barros, Guilherme , Bass, David I. , Levitt, Michael R. , Young, Christopher C. , Naylor, Ryan M. , Crowley, R. Webster , Serrone, Joseph C. , Kan, Peter , Binning, Mandy J., Veznedaroglu, Erol, Boulos, Alan S. , Lopes, Demetrius Klee , Kan, Peter , Tawk, Rabih G , Levitt, Michael R , Siddiqui, Adnan H , Hanel, Ricardo A , Lanzino, Giuseppe , Tawk, Rabih G.

Journal of NeuroInterventional Surgery | August 13, 2024 | Volume: 17 | Issue: 9 | Pages: 956-960

10.1136/jnis-2024-021977 Get It

Background The optimal duration for dual antiplatelet therapy (DAPT) after stent-assisted coiling (SAC) of intracranial aneurysms is unclear. Longer-term therapy may reduce thrombotic complications but increase the risk of bleeding complications. Methods A retrospective review of prospectively maintained data at 12 institutions was conducted on patients with unruptured intracranial aneurysms who underwent SAC between January 1, 2016 and December 31, 2020, and were followed ≥6 months postprocedure. The type and duration of DAPT, stent(s) used, outcome, length of follow-up, complication rates, and incidence of significant in-stent stenosis (ISS) were collected. Results Of 556 patients reviewed, 450 met all inclusion criteria. Nine patients treated with DAPT <29 days after SAC and 11 treated for 43–89 days were excluded from the final analysis as none completed their prescribed duration of treatment. Eighty patients received short-term DAPT. There were no significant differences in the rate of thrombotic complications during predefined periods of risk in the short, medium, or long-term treatment groups (1/80, 1.3%; 2/188, 1.1%; and 0/162, 0%, respectively). Similarly, no differences were found in the rate of hemorrhagic complications during period of risk in any group (0/80, 0%; 3/188, 1.6%; and 1/162, 0.6%, respectively). Longer duration DAPT did not reduce ISS risk in any group. Conclusions Continuing DAPT >42 days after SAC did not reduce the risk of thrombotic complications or in-stent stenosis, although the risk of additional hemorrhagic complications remained low. It may be reasonable to discontinue DAPT after 42 days following non-flow diverting SAC of unruptured intracranial aneurysms.
Carotid Artery Angioplasty and Stenting: 2-Dimensional Operative Video
Darwal, Maureen A, Liebman, Kenneth, Binning, Mandy J., Bain, Mark, Bendock, Bernard, Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Levy, Elad, Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Turner, Raymond D , Veznedaroglu, Erol, Welch, Babu G. , Schirmer, Clemens M , Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levitt, Michael R. , Levy, E, Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Ringer, Andrew J. , Rodriguez, Rafael, Siddiqui, Adnan H. , Aziz‐Sultan, Mohammad Ali , Tawk, Rabih G. , Thomas, Ajith J , White, Jonathan Samuel

Operative Neurosurgery | August 12, 2021 | Volume: 19 | Issue: 6 | Pages: E595-E596

10.1093/ons/opaa275 Get It

Abstract Carotid artery angioplasty and stenting (CAS) has been shown to be equally effective as carotid endarterectomy (CEA) for carotid stenosis in both symptomatic and asymptomatic disease. 1 In patients who are considered high risk for endarterectomy, CAS is safe and effective. 2 While this is a common procedure, proper technique is crucial to ensure that the procedure is safe with minimal risk of stroke. This patient consented to treatment. The following is a video detailing the CAS procedure in a 77-yr-old male with a symptomatic 65% carotid stenosis (by NASCET criteria 3 ) in a patient with prior CEA.
Endovascular Coil Embolization of a Posterior Communicating Artery Aneurysm: 2-Dimensional Operative Video
Darwal, Maureen A, Hakma, Zakaria, Binning, Mandy J., Bain, Mark, Bendock, Bernard, Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Sultan, Ali, Turner, Raymond, Veznedaroglu, Erol, Welch, Babu G. , White, Jonathan, Schirmer, Clemens M , Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levitt, Michael R. , Levy, Elad I. , Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Ringer, Andrew J. , Rodriguez, Rafael, Siddiqui, Adnan H. , Tawk, Rabih G. , Thomas, Ajith J , White, Jonathan A.

Operative Neurosurgery | August 12, 2021 | Volume: 19 | Issue: 6 | Pages: E597-E598

10.1093/ons/opaa278 Get It

Abstract Since the International Subarachnoid Aneurysm Trial, 1 endovascular treatment has been the favored treatment for appropriate ruptured intracranial aneurysms. While our endovascular technology has advanced to allow us to treat the majority of intracranial aneurysms, simple coil embolization is still the most common modality. This video demonstrates the fundamentals of aneurysm catheterization and coiling for safe treatment. In addition, the set-up and devices are detailed. This video is to add to the library of basic techniques that will aid a large number of practitioners. This patient consented to endovascular treatment. The video demonstrates endovascular coil embolization of a posterior communicating artery aneurysm in a 76-yr-old female who presented with a subarachnoid hemorrhage. Image of biplane suite in video used courtesy of Siemens Medical Solutions USA, Inc. Illustration at 5:12 reprinted from Yasargil MG, et al, Microneurosurgery IV B , p. 9, Thieme, New York, 1995.
Mechanical Thrombectomy of Carotid Terminus Occlusion Using Direct Aspiration Technique—Video Illustration: 2-Dimensional Operative Video
Kasab, Sami Al , Sattur, Mithun G. , Spiotta, Alejandro M , Group, ENRG, Bain, Mark, Bendock, Bernard, Binning, Mandy J., Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Levitt, Michael R. , Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Ringer, Andrew J. , Rodríguez, Rafael, Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Sultan, Ali, Turner, Raymond D , Veznedaroglu, Erol, Welch, Babu G. , White, Jonathan, Ogilvy, Christopher S. , Levitt, Michael R , Schirmer, Clemens M , Ogilvy, Christopher S , Porto, Guilherme , Group, ENRG, Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levy, Elad I. , Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Rodriguez, Rafael, Siddiqui, Adnan H. , Tawk, Rabih G. , Thomas, Ajith J , White, Jonathan A.

Operative Neurosurgery | July 31, 2021 | Volume: 21 | Issue: 5 | Pages: E441-E442

10.1093/ons/opab272 Get It

Abstract Acute carotid terminus occlusion (CTO) is responsible for up to 5% of acute ischemic strokes secondary to emergent large vessel occlusion (ELVO) and up to 20% of acute internal carotid artery (ICA) occlusions. 1 The term “CTO” has also been used to describe occlusions in the supra-clinoid segment or at the bifurcation of the ICA. Compared to other ELVOs, patients with CTO present with higher stroke severity and larger infarct volume, likely to be a result of disruption of direct Circle of Willis collaterals across the anterior communicating artery (AComA) and posterior communicating artery (PComA). 2,3 Similary, CTO is usually associated with worse prognosis compared to other ELVOs in general. With regard to response to treatment, previous studies have reported significantly lower recanalization rates with intravenous alteplase with CTO compared to M1 segment occlusion. With regard to the safety and efficacy of mechanical thrombectomy, prior reports provide conflicting results with some reporting lower successful recanalization rates with CTO compared to M1 occlusion, and others reporting similar results. In our experience, we have found that successful recanalization of CTO can be achieved with a similar approach to M1 occlusions utilizing a direct aspiration first pass technique (ADAPT). 3,4 Herein, we present a case of CTO for which we performed mechanical thrombectomy using ADAPT. This procedure was an emergent standard of care procedure for which a consent was not required and so not obtained.
Ulnar Artery Access: A Nontraditional Access Site for Diagnostic Cerebral Angiography and Neurointervention: 2-Dimensional Operative Video
Dossani, Rimal H., Cappuzzo, Justin M. , Sonig, Ashish , Almayman, Faisal, Siddiqui, Adnan H. , Davies, Jason M. , Bain, Mark, Bendock, Bernard, Binning, Mandy J., Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Sultan, Ali, Turner, Raymond D , Veznedaroglu, Erol, Welch, Babu G. , White, Jonathan A. , Davies, Jason M , Siddiqui, Adnan H , Schirmer, Clemens M , Waqas, Muhammad , Levy, Elad I. , Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levitt, Michael R. , Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Ringer, Andrew J. , Rodriguez, Rafael, Tawk, Rabih G. , Thomas, Ajith J

Operative Neurosurgery | June 30, 2021 | Volume: 21 | Issue: 4 | Pages: E350-E352

10.1093/ons/opab221 Get It

Abstract Transfemoral access has long been the main access site for cerebral angiography and neurointerventional procedures. Radial access is accepted as an alternative to the traditional transfemoral approach. Ulnar access may be undertaken if the radial artery is occluded or small caliber, or when radial artery preservation is needed. The safety and feasibility of ulnar access for neuroangiographic procedures has been demonstrated. 1-3 In this operative video, we demonstrate ulnar artery access in a patient in whom radial artery preservation was desired. We further elaborate on the technical nuances of this access. This nontraditional access site offers the same advantages as radial access, avoiding the need to switch to femoral artery access. A preoperative Allen's test is not necessary. Ultrasound imaging is used to aid in the identification and successful puncture of the ulnar artery. A medial to lateral approach for ulnar artery puncture is advised to avoid injury to the ulnar nerve. Careful application of wrist closure bands avoids hematoma accumulation. The patient gave informed consent for the procedure and video recording. Institutional review board approval was deemed unnecessary. Video. © University at Buffalo, May 2021. Used with permission.
Neuroendovascular Management of Acute Ischemic Basilar Strokes: 2-Dimensional Operative Video
Porto, Guilherme , Sattur, Mithun G. , Kasab, Sami Al , Spiotta, Alejandro M , Bain, Mark, Bendock, Bernard, Binning, Mandy J., Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Levitt, Michael , Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Rodríguez, Rafael, Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Sultan, Ali, Turner, Raymond D , Veznedaroglu, Erol, Welch, Babu G. , Porto, Guilherme B F , Schirmer, Clemens M , Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levitt, Michael, Levy, Elad I. , Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Ringer, Andrew J. , Rodriguez, Rafael, Siddiqui, Adnan H. , Tawk, Rabih G. , Thomas, Ajith J , White, Jonathan Samuel

Operative Neurosurgery | June 15, 2021 | Volume: 21 | Issue: 4 | Pages: E346-E347

10.1093/ons/opab180 Get It

Abstract Basilar artery occlusions (BAOs) are devastating ischemic strokes that account for 1% of all strokes with high morbidity and mortality; however, neuroendovascular techniques such as ADAPT have recently revolutionized the clinical outcomes of these patients. 1-3 Common underlying pathology in patients with BAO include intracranial atherosclerotic disease (ICAD) as well as thromboembolic origin. 4 Basilar artery ICAD in a setting of acute stroke portends a poor prognosis and post-thrombectomy residual critical flow limiting stenosis treatment options, including balloon angioplasty with or without stent placement. 5-7 We present a video illustration of neuroendovascular technique and challenges encountered when managing this pathology. Image at 5:42 reprinted with permission from Alawieh et al, Lessons learned over more than 500 stroke thrombectomies using ADAPT with increasing aspiration catheter size, Neurosurgery , 86(1), 2020, pp. 61-70, with permission from the Congress of Neurological Surgeons. 1
Carotid In-Stent Stenosis: Cutting Balloon Angioplasty: 2-Dimensional Operative Video
Ravindran, Krishnan , Tawk, Rabih G. , Bain, Mark, Bendock, Bernard, Binning, Mandy J., Boulos, Alan S. , Crowley, Webster, Fessler, Richard D., Guterman, Lee R., Hoit, Daniel , Hopkins, L. Nelson , Howington, Jay U., James, Robert F. , Jankowitz, Brian T. , Kan, Peter , Khalessi, Alex A, Kim, Louis J. , Langer, David J. , Levitt, Michael R. , Mack, William J. , Mericle, Robert A., Ogilvy, Chris, Replogle, Robert, Riina, Howard A. , Ringer, Andrew J. , Rodríguez, Rafael, Saugaveau, Eric, Schirmer, Clemens M. , Spiotta, Alex, Sultan, Ali, Turner, Raymond, Veznedaroglu, Erol, Welch, Babu G. , Ogilvy, Christopher S. , Tawk, Rabih G , Levitt, Michael R , Schirmer, Clemens M , Ogilvy, Christopher S , Domingo, Ricardo A. , Arthur, Adam Stephen , Grande, Andrew Walker , Hanel, Ricardó A. , Kim, Louis J. , Lanzino, Giuseppe , Levy, Elad I. , Lopes, Demetrius K. , Mocco, J , Pandey, Aditya S , Rodriguez, Rafael, Siddiqui, Adnan H. , Thomas, Ajith J , White, Jonathan Samuel

Operative Neurosurgery | June 7, 2021 | Volume: 21 | Issue: 3 | Pages: E240-E241

10.1093/ons/opab194 Get It

Abstract In-stent stenosis has a reported prevalence of 14% to 19% at 1-yr follow-up after carotid stenting and is associated with an increased risk of acute ischemic stroke. 1,2 Risk factors include female sex, diabetes, and dyslipidemia. Cutting balloon angioplasty is a safe and effective treatment modality for the treatment of carotid in-stent stenosis, and alternative treatment options include observation with medical management and placement of another stent. 3,4 The authors present the case of a 61-yr-old man with carotid in-stent restenosis and progressive worsening on serial imaging with ultrasound. The patient had a history of carotid stenting for symptomatic stenosis 6 mo prior and was maintained on aspirin and clopidogrel. In light of the progressive worsening, the in-stent stenosis was confirmed on computed tomography (CT) angiogram. The options were discussed with the patient and he consented for treatment with cutting balloon angioplasty. Final angiogram showed improvement of the luminal diameter with a residual stenosis of 15%. The patient tolerated the procedure well and was discharged home on postoperative day 1. Follow-up ultrasound demonstrated moderate improvement in peak systolic velocities, and the plan is to continue observation with a clinical follow-up and repeat carotid Dopplers at 3 mo.