Investigation of pulsed 1.44-μm Nd:YAG laser in nasal and sinus surgery: in vitro and in vivo animal study

The Nd:YAG laser 1.44 micrometers wavelength is a relatively new wavelength with water absorption coefficient higher even than 1.06 micrometers , permitting the creation of a more precise lesion with less damage to surrounding tissue. Very little, however, is known about its effects in live experimental model. The non-contact 1.44 micrometers Nd:YAG laser was used in four animals (dogs) to perform a resection of middle turbinate and to create a 1 cm lesion on the septal mucosa and inferior turbinate in the left side through a sinuscope. The same procedure was performed on the opposite side using microsurgical forceps as a control. The animals were followed-up, examined endoscopically, and sacrificed after 48 hours (1 animal), 1 month (1 animal) and 2 months (2 animals). Moderate-to-severe bleeding was commonly encountered on the control side, which obscured vision, and required packing in 2 dogs. In contrast, the laser had a satisfactory hemostatic result with easy control for endoscopic resection. Normal healing was observed under gross and by histologic examination 48 hours and 1 month after the surgery and healing was complete by 2 months. There was more scaring and adhesions produced by the forceps on the control side. Histologically, tissue thermal damage produced by the laser was superficial and confined to the lesion. The epithelial regeneration has been nearly completed in 1 month, with normal mucosa coverage in 2 months after the surgery. This study suggests that the 1.44 micrometers wavelength of the Nd:YAG should be considered as safe and reliable for intranasal application.