Light amplifier and method of photothemolysis
Heart-synchronized pulsed laser system
Intracavity modulated pulsed laser with a variably controllable modulation frequency
Dermatological laser apparatus and method
Method and apparatus for depilation using pulsed electromagnetic radiation
Intracavity modulated pulsed laser and methods of using the same
Method for treatment of unwanted veins and device therefor
Apparatus for laser-assisted intra-coronary transmyocardial revascularization and other applications
Gauging system for monitoring channel depth in percutaneous endocardial revascularization Patent #: 5893848
ApplicationNo. 036503 filed on 03/06/1998
US Classes:606/15, With optical fiber606/10, Systems606/11, Beam energy control or monitoring606/12Condition responsive
ExaminersPrimary: Dvorak, Linda C. M.
Assistant: Harris-Ogugua, Sonya
Attorney, Agent or Firm
International ClassA61B 018/180
AbstractAn apparatus for percutaneous laser revascularization of a patient's beating heart includes a laser system that produces a pulsed laser beam with a wavelength in a range of approximately 1.7 μm to approximately 2.15 μm, each pulse of the laser beam having a pulse duration in a range of approximately 1 ms and greater and having a pulse energy in a range of approximately 5 J to approximately 25 J. The pulse can include a train of micropulses. A fiber optic element that is coupled to the laser system is arranged with a catheter to pass through a vasculature of the patient and to deliver pulses of the laser beam to an interior wall of the patient's heart. The laser system can include a flash lamp-pumped laser in which a large capacitor bank discharges only a fraction of its stored energy through a flash lamp to fire the laser, wherein the capacitor discharge is turned off by a switchable device, such as a high current transistor, after the integrated energy of a laser pulse reaches a selected value. A pair of concave mirrors are arranged facing either end of the laser rod to form a resonant cavity, wherein each mirror has a curvature selected to compensate for changes in the index of refraction of the laser rod as a function of radius due to heating from the flash lamp. The laser system can be triggered to provide a laser pulse only during a refractive portion of the patient's heartbeat cycle. The apparatus is capable of forming a channel in the patient's heart to any desired depth by applying only a single laser pulse.