Abstract
The results of operation on the accessory nasal sinuses in general are not entirely satisfactory. This is especially true of operations performed on the ethmoid sinuses. With this in mind, the present series of experiments was carried out, together with some studies on the physiology of the nose and sinuses, in the hope of finding possible causes for failure in operations on the sinuses. In connection with some attempts to produce acute sinusitis experimentally in dogs, the septum between the frontal sinuses of two dogs was removed. The septum was bitten away cleanly and smoothly with rongeurs, including the lining on both sides. A membranous septum promptly reformed. Thinking that the bare strip of bone left after removal of the septum might be responsible in some way for failure of the artificial opening to remain patent, it was decided to remove strips of varying widths from variously shaped