1
|
Liu Y, Gebrezgiabhier D, Zheng Y, Shih A, Chaudhary N, Pandey A, Larco J, Madhani S, Abbasi M, Shahid A, Quinton R, Kadirvel R, Brinjikji W, Kallmes D, Savastano L. Arterial Collapse during Thrombectomy for Stroke: Clinical Evidence and Experimental Findings in Human Brains and In Vivo Models. AJNR Am J Neuroradiol 2022; 43:251-257. [PMID: 35027348 PMCID: PMC8985669 DOI: 10.3174/ajnr.a7389] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 10/04/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND AND PURPOSE Aspiration thrombectomy has become a preferred approach to recanalize large-vessel occlusion in stroke with a growing trend toward using larger-bore catheters and stronger vacuum pumps. However, the mechanical response of the delicate cerebral arteries to aspiration force has not been evaluated. Here, we provide preclinical and clinical evidence of intracranial arterial collapse in aspiration thrombectomy. MATERIALS AND METHODS We presented a clinical case of arterial collapse with previously implanted flow diverters. We then evaluated the effect of vacuum with conventional aspiration catheters (with and without stent retrievers) in a rabbit model (n = 3) using fluoroscopy and intravascular optical coherence tomography. Then, in a validated human cadaveric brain model, we conducted 168 tests of direct aspiration thrombectomy following an experimental design modifying the catheter inner diameter (0.064 inch, 0.068 inch, and 0.070 inch), cerebral perfusion pressures (mean around 60 and 90 mm Hg), and anterior-versus-posterior circulation. Arterial wall response was recorded and graded via direct transluminal observation. RESULTS Arterial collapse was observed in both the patient and preclinical experimental models. In the human brain model, arterial collapse was observed in 98% of cases in the M2 and in all the cases with complete proximal flow arrest. A larger bore size of the aspiration catheter, a lower cerebral perfusion pressure, and the posterior circulation in comparison with the anterior circulation were associated with a higher probability of arterial collapse. CONCLUSIONS Arterial collapse does occur during aspiration thrombectomy and is more likely to happen with larger catheters, lower perfusion pressure, and smaller arteries.
Collapse
Affiliation(s)
- Y. Liu
- From the Departments of Radiology (Y.L., M.A., R.K., W.B., D.F.K.),Departments of Mechanical Engineering (Y.L., Y.Z., A.J.S.)
| | - D. Gebrezgiabhier
- Neurosurgery (D.G., A.S.P., L.E.S.),UCSF Graduate Program in Bioengineering (D.G.), University of California Berkeley, San Francisco, California
| | - Y. Zheng
- Departments of Mechanical Engineering (Y.L., Y.Z., A.J.S.),Department of Mechanical Engineering (Y.Z.), Worcester Polytechnic Institute, Worcester, Massachusetts
| | - A.J. Shih
- Departments of Mechanical Engineering (Y.L., Y.Z., A.J.S.)
| | - N. Chaudhary
- Radiology (N.C.), University of Michigan, Ann Arbor, Michigan
| | | | | | | | - M. Abbasi
- From the Departments of Radiology (Y.L., M.A., R.K., W.B., D.F.K.)
| | - A.H. Shahid
- Neurosurgery (J.L.A.L., S.I.M., A.H.S., L.E.S.)
| | - R.A. Quinton
- Division of Anatomic Pathology (R.A.Q.), Mayo Clinic, Rochester, Minnesota
| | - R. Kadirvel
- From the Departments of Radiology (Y.L., M.A., R.K., W.B., D.F.K.)
| | - W. Brinjikji
- From the Departments of Radiology (Y.L., M.A., R.K., W.B., D.F.K.)
| | - D.F. Kallmes
- From the Departments of Radiology (Y.L., M.A., R.K., W.B., D.F.K.)
| | - L.E. Savastano
- Neurosurgery (J.L.A.L., S.I.M., A.H.S., L.E.S.),Neurosurgery (D.G., A.S.P., L.E.S.)
| |
Collapse
|
2
|
Preclinical modeling of mechanical thrombectomy. J Biomech 2021; 130:110894. [PMID: 34915309 DOI: 10.1016/j.jbiomech.2021.110894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 11/21/2022]
Abstract
Mechanical thrombectomy to treat large vessel occlusions (LVO) causing a stroke is one of the most effective treatments in medicine, with a number needed to treat to improve clinical outcomes as low as 2.6. As the name implies, it is a mechanical solution to a blocked artery and modeling these mechanics preclinically for device design, regulatory clearance and high-fidelity physician training made clinical applications possible. In vitro simulation of LVO is extensively used to characterize device performance in representative vascular anatomies with physiologically accurate hemodynamics. Embolus analogues, validated against clots extracted from patients, provide a realistic simulated use experience. In vitro experimentation produces quantitative results such as particle analysis of distal emboli generated during the procedure, as well as pressure and flow throughout the experiment. Animal modeling, used mostly for regulatory review, allows estimation of device safety. Other than one recent development, nearly all animal modeling does not incorporate the desired target organ, the brain, but rather is performed in the extracranial circulation. Computational modeling of the procedure remains at the earliest stages but represents an enormous opportunity to rapidly characterize and iterate new thrombectomy concepts as well as optimize procedure workflow. No preclinical model is a perfect surrogate; however, models available can answer important questions during device development and have to date been successful in delivering efficacious and safe devices producing excellent clinical outcomes. This review reflects on the developments of preclinical modeling of mechanical thrombectomy with particular focus on clinical translation, as well as articulate existing gaps requiring additional research.
Collapse
|
3
|
Liu Y, Larco JLA, Madhani SI, Shahid AH, Quinton RA, Kadirvel R, Kallmes DF, Brinjikji W, Savastano LE. A Thrombectomy Model Based on Ex Vivo Whole Human Brains. AJNR Am J Neuroradiol 2021; 42:1968-1972. [PMID: 34556479 PMCID: PMC8583258 DOI: 10.3174/ajnr.a7291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/08/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The persistent challenges in thrombectomy for large-vessel occlusion, such as suboptimal complete recanalization and first-pass effect imply an insufficient understanding of the artery-clot-device interaction. In this study, we present a thrombectomy model using fresh human brains, which can capture the artery-clot-device interaction through concurrent transmural and angiographic visualizations. MATERIALS AND METHODS Fresh nonfrozen whole adult human brains were collected and connected to a customized pump system tuned to deliver saline flow at a physiologic flow rate and pressure. Angiography was performed to verify the flow in the anterior-posterior and vertebrobasilar circulations and collaterals. Large-vessel occlusion was simulated by embolizing a radiopaque clot analog. Thrombectomy was tested, and the artery-clot-device interactions were recorded by transmural and angiographic videos. RESULTS Baseline cerebral angiography revealed excellent penetration of contrast in the anterior-posterior and vertebrobasilar circulations without notable arterial cutoffs and with robust collaterals. Small branches (<0.5 mm) and perforating arteries were consistently opacified with good patency. Three device passes were performed to achieve recanalization, with failure modes including elongation, fragmentation, and distal embolization. CONCLUSIONS This model enables concurrent transmural and angiographic analysis of artery-clot-device interaction in a human brain and provides critical insights into the action mechanism and failure modes of current and upcoming thrombectomy devices.
Collapse
Affiliation(s)
- Y Liu
- From the Departments of Radiology (Y.L., R.K., D.F.K., W.B.)
| | - J L A Larco
- Neurosurgery (J.L.A.L., S.I.M., A.H.S., L.E.S.)
| | - S I Madhani
- Neurosurgery (J.L.A.L., S.I.M., A.H.S., L.E.S.)
| | - A H Shahid
- Neurosurgery (J.L.A.L., S.I.M., A.H.S., L.E.S.)
| | - R A Quinton
- Division of Anatomic Pathology (R.A.Q.), Mayo Clinic, Rochester, Minnesota
| | - R Kadirvel
- From the Departments of Radiology (Y.L., R.K., D.F.K., W.B.)
| | - D F Kallmes
- From the Departments of Radiology (Y.L., R.K., D.F.K., W.B.)
| | - W Brinjikji
- From the Departments of Radiology (Y.L., R.K., D.F.K., W.B.)
| | | |
Collapse
|