CHRONIC MASTOIDITIS 341 Modifications of the Standard Operation. Dissatisfaction with the prolonged care of an open mastoid cavity which is exposed to the ravages from external sources such as washing, hair shampoo, swimming, meatal infection, etc. has led surgeons to explore means of avoiding this. One of the early methods was to fill the mastoid cavity with a muscle graft swung on a pedicle from the temporalis muscle. No meatal flap was cut. This was satisfactory only if every minute particle of disease had been removed, and it has largely been abandoned. Fig, 175. Radical mastoid operation. Korner's meatal plastic. The sharp-pointed tenotomy knife has been passed through the external meatus and is making the upper cut of the tongue-shaped flap. The lower cut is indicated by dotted lines. More recently the combined approach technique has been evolved. At this operation, performed under the operating microscope, the middle ear is entered, after mastoid disease has been eradicated, through the bony pos- terior meatus instead of removing the outer attic wall and the bridge over the aditus. The posterior meatal wall is left intact and no flap is cut. The operation is a lengthy one and the facial nerve is at greater risk. Visualiza- tion of all parts of the middle ear cavity may not readily be made, especially by those who have not performed many operations by this technique. Cholesteatoma may not be completely removed around the ossicles, and it will recur. Such recurrence is more difficult to detect in its early stage than if the mastoid cavity is fully exposed to view through the window, and thus is not easily removed without converting the operation to a standard radical type.