A PRACTICAL one stage operative technic for the improvement of hearing in otosclerosis first became available in 1938 when Lempert1 introduced the fenestration operation. From a small beginning, beset with many failures, the operation has developed to a highly refined procedure which has been carried out on several thousands of patients suffering from otosclerosis, with varying but with generally increasing success.
The evolutionary development of the fenestration operation has taken several directions. In one of these directions, pursued at the Wesley Memorial Hospital and Northwestern University Medical School as a result of research studies carried out during the last four years on the monkey, a new fenestration technic has developed which will be described in the present communication, with the results thus far observed.
Whether or not the new fenestration technic represents an improvement over other technics will be determined by a comparison of the hearing results in a sufficiently