Ablation of bone and methacrylate by a prototype mid‐infrared erbium:YAG laser

Abstract

An erbium:YAG laser was used to generate 200-microseconds pulses of mid-infrared 2.94-microns light in both the single and multimode configurations. Laser pulses were focused on the surfaces of both rabbit long bones and methacrylate blocks, and the tissue response was examined histologically. The depth of thermal injury was determined by ocular micrometry. Over all energy levels tested, the erbium:YAG laser produced ablation of bone and methacrylate with minimal thermal damage to adjacent tissue. Increasing the laser energy per pulse produced increasingly wider and deeper grooves in both bone and methacrylate. However, such increase in laser energy produced a proportionately greater increase in the zone of thermal injury in methacrylate as compared with bone. These studies suggest the feasibility of a surgical erbium:YAG laser in orthopaedics and other forms of ablative surgery.

Biomedical Optics and Lasers

“…Since beginning of 1980's, following development of CO 2 [58] and erbium family lasers [59], researchers have widened operational scope of laser systems for bone removal. Even though; erbium lasers looks like similar bone removal capacity as with mechanical instruments, bone healing following removal procedure is still controversial due to collateral heat production with laser beam [60,61].…”

Advances in bone surgery: the Er:YAG laser in oral surgery and implant dentistry

“…These in vivo experiments were based on previous results from the same group disclosing that the zone of thermal injury after Er:YAG laser ablation with increasing laser energy was much more pronounced in methacrylate than in rabbit long bones. 100 Thus in vital tissue, the thermal effects of laser treatment were much more complex and heat distribution had a much stronger influence on adjacent structures. A further influence of laser parameters on tissue damage was demonstrated by Walsh et al 101 In their study analyzing Er:YAG laser ablation of skin, cornea, aorta, and bone, Q-switched pulses caused less thermal damage, 101 could also show that pulse fluences greater than 20 J/cm 2 caused plasma formation by which ablation efficiency was decreased.…”

Lasers in percutaneous disc surgery: Beneficial technology or gimmick?

“…The ablation threshold for nucleus pulposus is 7 mJ/mm2 (39). It is excellently absorbed by tissuewater and has also been used for experimental osteotomies (48). In experimental studies, this laser offers the advantage of efficient ablation of nucleus pulposus (e.g.…”