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Eleven animals (five cats and six squirrel monkeys) were studied before and after being rendered hypothyroid by, surgical excision or radioactive ablation of the thyroid gland. Blood chemistry studies, before ablation and after, proved the presence of hypothyroid state. Audiometric studies by the behaviorally trained avoidance technique and electronystagmograms indicated hypoactivity regarding hearing and labyrinthine function. In one cat given thyroid hormone to full compensation level, the high frequency hearing loss returned to normal. Studies of temporal bone specimens of the five cats: hypothyroid, thyroid compensated, and control, microscopically showed no morphological alterations. Presumably functional changes were due to biochemical involvement which failed to show as a morphological one.

Re-evaluation of skin grafting techniques in surgically-created temporal bone cavities has forced itself to my attention for two reasons. First, as years of follow-up treatment of primarily grafted cavities go by, numerous initially dry ears break down with secondary infection of the skin lining. At first, the Texas Gulf coast climate was blamed. But the same thing apparently occurs elsewhere in the United States, according to informal conversation with others (Shambaugh, Walsh, and House). The second factor is the changing con cept of reconstructive otologic surgery for hearing conservation sparked by the work of Moritz, 17 Zöllner, 25,26 and Wullstein. 24 Prog ress continues as others 2,10,12,15,16 continue work with the principles of tympanoplasty and myringoplasty. The days of the classical radical and modified radical mastoidectomies as well as large cavity fenestra tions are numbered. However, in my opinion, the use of preserved autogenous skin for delayed grafting has a place in our present day armamentarium.The idea of reporting a technique for using preserved skin re sulted from follow-up care of bilaterally fenestrated cases. A primary split thickness skin graft was used in one ear and a delayed autogenous graft of preserved skin was used in the opposite ear of these cases. Almost invariably the primarily grafted ear was the one that required treatment most often for secondary infection; the ear with the de layed graft would continue dry and uninfected.Biopsies of the two ears in such cases gave no clue as to why the delayed graft resisted infection.