title: Hydrodynamic comparison of the Penumbra system and commonly available syringes in forced-suction thrombectomy.
abstract: BACKGROUND
  The Penumbra system uses a coaxial separator and continuous extracorporeal suction to remove a clot from a cerebral artery. Forced-suction thrombectomy (FST) involves aspirating clots through the same reperfusion catheter using only a syringe, decreasing the procedure time and supplies needed.
  
  
  OBJECTIVE
  To evaluate multiple combinations of catheters and syringes to determine the optimal pairing for use in FST.
  
  
  METHODS
  Tests were performed using both the Penumbra system and syringes to aspirate water through Penumbra 0.041 inch (041), 4Max, 0.054 inch (054) and 5Max reperfusion catheters and a shuttle sheath. Dynamic pressure and flow at the catheter tip were calculated from the fill times for each system. Static pressure and force for each aspiration source were determined with a vacuum gauge.
  
  
  RESULTS
  All syringes provided significantly higher dynamic pressure at the catheter tip than the Penumbra system (p<0.001). Increasing syringe volume significantly increased static pressure (p<0.001). Both flow and aspiration force significantly increased with catheter size (p<0.001). Cases are presented to demonstrate the clinical value of the laboratory principles.
  
  
  CONCLUSIONS
  Maximizing static and dynamic pressure when performing FST is achieved by aspirating with a syringe possessing both the largest volume and the largest inlet diameter available. Maximizing aspiration force and flow rate is achieved by using the largest catheter possible.
authors.affiliation: VCU Department of Neurosurgery, Virginia Commonwealth University, Richmond, Virginia, USA.
authors.forename: Scott Douglas
authors.initials: SD
authors.lastname: Simon
authors.forename: Casey Paul
authors.initials: CP
authors.lastname: Grey
mesh_terms: D017542:Aneurysm, Ruptured / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery; D057785:Catheters / Q000592:standards; D006801:Humans; D057446:Hydrodynamics; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000601:surgery; D002532:Intracranial Aneurysm / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery; D020765:Intracranial Arterial Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000209:etiology / Q000601:surgery; D013396:Suction / Q000295:instrumentation / Q000379:methods / Q000592:standards; D013523:Surgical Equipment / Q000592:standards*; D013594:Syringes / Q000592:standards; D017131:Thrombectomy / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D016896:Treatment Outcome
keywords: Catheter; Intervention; Stroke; Technique; Thrombectomy