A Laser-induced Liquid Jet Catheter System: A Novel Endovascular Device for Rapid and Reliable Fibrinolysis in Acute Cerebral Embolism

Abstract

Objective: Mechanical removal of intravascular clots in addition to administration of tissue plasminogen activator are both desirable for improved outcome in acute embolic stroke. We have developed a novel endovascular catheter system for rapid and reliable mechanical recanalization of cerebral embolisms with little or no requirement for fibrinolytic agents. Here, we describe the evaluation of this device in vitro.

Materials: Pulsed liquid jets were generated and ejected from the catheter exit by accelerating cold physiological saline (4 °C, 40 mL/h) using the energy of a pulsed holmium:yttrium-aluminum-garnet (YAG) laser (3 Hz, 1.2 W). Accessibility beyond the tortuous cavernous portion of the internal carotid artery to the M1 and A1 regions was confirmed using a transparent model of the human cerebral artery. Mechanical characteristics of the liquid jets were evaluated with a high-speed camera. Liquid jets of physiological saline or urokinase solution (1 200 IU/mL) were exposed to artificial thrombi made of human blood under temperature monitoring. Remnants of thrombi were collected and incubated at 37 °C for 10 min for estimation of fibrinolysis rates.

Results: The jet velocity (maximum: 5 m/s) was controlled by changing the laser energy. The fibrinolysis rates (mean±SD) after exposure to jets of saline or urokinase solution for 45 s were 62.2±16.4 and 94.0±3.4%, respectively, and were significantly better than the rate of 8.1±2.0% with administration of urokinase alone. The local temperature rise was less than 8 °C.

Conclusions: The results show that the laser-induced liquid jet catheter system may be a powerful tool for mechanical destruction of emboli and augmentation of the effect of fibrinolytic agents beyond the tortuous part of the internal carotid artery.

Key words

holmium-YAG laser - minimally invasive neurosurgery - shock wave - water jet

References

• 1 NINDS. The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group. . Tissue plasminogen activator for acute ischemic stroke. The National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group.  N Engl J Med. 1995;  333 1581-1587
• 2 Grotta JC, Alexandrov AV. tPA-associated reperfusion after acute stroke demonstrated by SPECT.  Stroke. 1998;  29 429-432
• 3 Demchuk AM, Felburg RA, Alexandrov AV. Clinical recovery from acute ischemic stroke after early reperfusion of the brain with intravenous thrombolysis.  N Engl J Med. 1999;  340 894-895
• 4 Heiss WD, Grond M, Thiel A. et al . Tissue at risk of infarction rescued by early reperfusion: a positron emission tomography study in systemic recombinant tissue plasminogen activator thrombolysis of acute stroke.  J Cereb Blood Flow Metab. 1998;  18 1298-1307
• 5 Rha JH, Saver JL. The impact of recanalization on ischemic stroke outcome: a meta-analysis.  Stroke. 2007;  38 967-973
• 6 Kase CS, Furlan AJ, Wechsler LR. et al . Cerebral hemorrhage after intra-arterial thrombolysis for ischemic stroke: the PROACT II trial.  Neurology. 2001;  57 1603-1610
• 7 Tirschwell DL, Coplin WM, Becker KJ. et al . Intra-arterial urokinase for acute ischemic stroke: factors associated with complications.  Neurology. 2001;  57 1100-1103
• 8 Hamm CW, Steffen W, Terres W. et al . Intravascular therapeutic ultrasound thrombolysis in acute myocardial infarctions.  Am J Cardiol. 1997;  80 200-204
• 9 Geschwind HJ, Nakamura F, Kvasnicka J. et al . Excimer and holmium yttrium aluminum garnet laser coronary angioplasty.  Am Heart J. 1993;  125 510-522
• 10 Topaz O, Vetrovec G. Laser for optical thrombolysis and facilitation of balloon angioplasty in acute myocardial infarction following failed pharmacologic thrombolysis.  Cathet Cardiovasc Diagn. 1995;  36 38-42
• 11 White CJ, Ramee SR, Collins TJ. et al . Holmium:YAG laser-assisted coronary angioplasty with multifiber delivery catheters.  Cathet Cardiovasc Diagn. 1993;  30 05-210
• 12 White RA, Kopchok GE, Tabbara MR. et al . Intravascular ultrasound guided holmium:YAG laser recanalization of occluded arteries.  Lasers Surg Med. 1992;  12 239-245
• 13 Chow K, Gobin YP, Saver J. et al . Endovascular treatment of dural sinus thrombosis with rheolytic thrombectomy and intra-arterial thrombolysis.  Stroke. 2000;  31 1420-1425
• 14 Smith WS. Safety of mechanical thrombectomy and intravenous tissue plasminogen activator in acute ischemic stroke. Results of the multi Mechanical Embolus Removal in Cerebral Ischemia (MERCI) trial, part I.  AJNR Am J Neuroradiol. 2006;  27 1177-1182
• 15 Flint AC, Duckwiler GR, Budzik RF. et al . Mechanical thrombectomy of intracranial internal carotid occlusion: pooled results of the MERCI and Multi MERCI Part I trials.  Stroke. 2007;  38 1274-1280
• 16 Hirano T, Komatsu M, Uenohara H. et al . A novel method of drug delivery for fibrinolysis with Ho:YAG laser-induced liquid jet.  Lasers Med Sci. 2002;  17 165-172
• 17 Hirano T, Komatsu M, Saeki T. et al . Enhancement of fibrinolytics with a laser-induced liquid jet.  Lasers Surg Med. 2001;  29 360-368
• 18 Asshauer T, Delacretaz G, Jansen ED. et al . Pulsed holmium laser ablation of tissue phantoms: correlation between bubble formation and acoustic transients.  Appl Phys B. 1997;  65 647-657
• 19 Asshauer T, Rink K, Delacretaz G. Acoustic transient generation by holmium-laser-induced cavitation bubbles.  J Appl Phys. 1994;  76 5007-5013
• 20 Francis CW, Blinc A, Lee S. et al . Ultrasound accelerates transport of recombinant tissue plasminogen activator into clots.  Ultrasound Med Biol. 1995;  21 419-424
• 21 Akiyama M, Ishibashi T, Yamada T. et al . Low-frequency ultrasound penetrates the cranium and enhances thrombolysis in vitro.  Neurosurgery. 1998;  43 828-832
• 22 Alexandrov AV, Molina CA, Grotta JC. et al . Ultrasound-enhanced systemic thrombolysis for acute ischemic stroke.  N Engl J Med.. 2004;  18 2170-2178
• 23 Hassenstein S, Hanke H, Kamenz J. et al . Vascular injury and time course of smooth muscle cell proliferation after experimental holmium laser angioplasty.  Circulation. 1992;  86 1575-1583
• 24 Leeuwen TG van, Meertens JH, Velema E. et al . Intraluminal vapor bubble induced by excimer laser pulse causes microsecond arterial dilation and invagination leading to extensive wall damage in the rabbit.  Circulation. 1993;  87 1258-1263
• 25 Hirano T, Uenohara H, Komatsu M. et al . Holmium: YAG laser-induced liquid jet dissector: A novel prototype device for dissecting organs without impairing vessels.  Minim Invas Neurosurg. 2003;  46 121-125
• 26 Nakagawa A, Hirano T, Komatsu M. et al . Holmium: YAG laser-induced liquid jet knife: Possible novel method for dissection.  Lasers Surg Med. 2002;  31 129-135
• 27 Sato Y, Nakagawa A, Hirano T. et al . Pulsed laser-induced liquid jet microcatheter system for rapid and reliable fibrinolysis in acute cerebral embolisms: Experiments on safety and preliminary application in porcine cranial vessels.  Min Invas Neurosurg. 2007;  50 212-218
• 28 Nakagawa A, Kumabe T, Kanamori M. et al . Clinical application of pulsed laser-induced liquid jet: Preliminary report in glioma surgery.  No Shinkei Geka (Jpn). 2008;  , [in press]

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