A controlled advancement laser ablation device is provided for precise ablation of body matter. The laser ablation device includes a laser energy transmission mechanism such as, e.g., a fiber optic fiber mounted for controlled translational longitudinal movement relative to a housing structure. A laser energy generator is optically connected to the laser energy transmission mechanism. A controlled advancement mechanism is provided in engagement with the laser energy transmission mechanism for advancing the mechanism through the housing structure at a controlled rated coordinated with the laser energy generator output to ablate body tissue. Controlled advancement mechanisms include constant and/or variable rate springs, motors, and other mechanisms which can be coordinated with the laser energy generator to advance the laser energy transmission mechanism as the targeted substance is ablated. The device is particularly suitable for use in transmyocardial revascularization (TMR) and angioplasty procedures.
This application is a continuation application of co-pending application Ser. No. 08/648638 filed May 13, 1996, which is incorporated by reference as if fully set forth herein.
An improved articulating device for use with a medical insertion instrument comprising in part a first tube having a plurality of ribs defining a plurality of bending segments, a second tube axially disposed within the first tube, and means for transmitting an axial deflecting pull load. Such device has improved controlled for positioning an end of the device at a selected position within the body. The articulating device has a generally constant moment of inertia and a polar moment of inertia that generally decreases from its proximal to distal end.
