title: MRI-guided sonothrombolysis of rabbit carotid artery.
abstract: The potential of magnetic resonance imaging-guided focused ultrasound (MRgFUS) combined with the thrombolytic drug recombinant tissue plasminogen activator (rt-PA) to dissolve clots in the carotid of a New Zealand rabbit in vivo is evaluated. A spherically focused transducer of 5-cm diameter, focusing at 10 cm and operating at 1 MHz, was used. A pulsed ultrasound protocol was used that maintains a tissue temperature increase of less than 1 °C in the clot (called safe temperature). MRgFUS has the potentials to dissolve clots that are injected in the carotid of rabbits in vivo. It was found that the time needed for opening the carotid artery using ultrasound and rt-PA was decreased compared with just using rt-PA. The time needed for opening the artery decreases with increasing acoustic intensity. With an intensity of 20 W/cm2 (spatial average temporal average), which is not causing artery heating, the time needed to completely open the artery was 70 minutes. The proposed protocol was monitored using magnetic resonance angiography every 1 minute.
authors.affiliation: Department of Electrical Engineering, Cyprus University of Technology, Cyprus; MEDSONIC Ltd, Limassol, Cyprus. Electronic address: cdamianou@cytanet.com.cy.
authors.forename: Christakis
authors.initials: C
authors.lastname: Damianou
authors.affiliation: MEDSONIC Ltd, Limassol, Cyprus; Department of Biomedical Engineering, City University, London, UK.
authors.forename: Venediktos
authors.initials: V
authors.lastname: Hadjisavvas
authors.affiliation: Department of Computer Science, Frederick University Cyprus, Limassol, Cyprus.
authors.forename: Nicos
authors.initials: N
authors.lastname: Mylonas
authors.affiliation: Lanition Lyceum, Limassol, Cyprus.
authors.forename: Andreas
authors.initials: A
authors.lastname: Couppis
authors.affiliation: Department of Magnetic Resonance Imaging, Polikliniki Ygia, Limassol, Cyprus.
authors.forename: Kleanthis
authors.initials: K
authors.lastname: Ioannides
mesh_terms: D000818:Animals; D016893:Carotid Stenosis / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D018810:Magnetic Resonance Angiography; D053783:Magnetic Resonance Imaging, Interventional; D011237:Predictive Value of Tests; D011817:Rabbits; D011994:Recombinant Proteins / Q000008:administration & dosage; D015912:Thrombolytic Therapy; D013927:Thrombosis / Q000473:pathology / Q000628:therapy*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage*; D014464:Ultrasonic Therapy / Q000295:instrumentation
chemical_list: D005343:Fibrinolytic Agents; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator
keywords: MRI; Ultrasound; stroke; thrombolysis