Repeated-Manual Aspiration with Maximum Pressure (r-MAX): A New Technique of Mechanical Thrombectomy Using Syringe Aspiration

OBJECTIVE: We report a new contact aspiration technique using syringe aspiration called repeated-manual aspiration with maximum pressure (r-MAX). CASE PRESENTATION: From January 2020 to May 2021, 18 patients underwent mechanical thrombectomy with r-MAX for occlusion of the internal carotid artery, the first division of the middle cerebral artery (M1), and basilar artery occlusion. In this method, the aspiration catheter is first guided to the occlusion site, and then, two VacLok syringes are connected to the aspiration catheter. Next, the three-way stopcock is released in one direction. After 15 seconds, the direction of the three-way stopcock is switched. In the meantime, negative pressure is reapplied through the syringe, and the direction of the three-way stopcock is switched again. After reapplying negative pressure through the syringe and switching the three-way stopcock two more times, the aspiration catheter is removed. First-pass thrombolysis in cerebral infarction (TICI) scale 3 recanalization was achieved in 11 out of 18 patients (61.1%). In all, 11 patients (61.1%) achieved modified Rankin Scale scores of 0–2 at 90 days. Asymptomatic hemorrhage was observed in two patients (11.1%), and no patients had symptomatic hemorrhage. CONCLUSION: The r-MAX technique using syringe aspiration can be employed as one of the methods of contact aspiration.