Erbium laser in middle ear surgery : in vitro and in vivo animal study

Cadaveric human temporal bones, cadaveric rabbits, and live rats were used to demonstrate the utility and safety of the erbium :yttrium-scandium-gallium-garnet (Er :YSGG) laser for otologic applications. The shallow penetration in water of this wavelength and its ability to ablate bony tissue with minimal collateral thermal effects spare underlying and adjacent structures and make it appealing for stapedotomy. The authors were able to satisfactorily perform small fenestra stapedotomy, atticotomy, facial nerve decompression, and mastoidectomy. Temperature measurements from the round window area during Er :YSGG stapedotomy recorded an elevation of less than 2°C, which is well within acceptable limits. An acoustic shock produced at the impact site is the major disadvantage and requires further in vivo investigation of the transient and sustained deleterious effects away from the application site. This work supports further investigation into potential applications of the Er :YSGG laser in otology.