Osteoma of the Mastoid

A CASE very similar to that exhibited at the November meeting. A woman, aged 36, complaining of deafness of four months' duration, and who had discovered the presence of the tumour accidentally. A hard hemispherical tumour the size of a bantam's egg projected behind the ear in the antral region, and also obstructed the meatus. Deafness of obstructive type. Operation: Skin incision following contour of growth. Hugh Jones's meatal flap attached by a pedicle consisting of the whole of the tissue, less the skin, elevated off the tumour. The contour of the tumour proved to be sharply defined from the normal outer table by a groove. As the position of the lateral sinus could not be made out in the skiagram, a trench was carefully cut with the electric burr until mastoid cells and normal diploe were exposed at all points, when a few taps of the chisel brought the tunmour away. Its inner aspect proved to be well defined, and the tumour, which measured 1 in. by 1 in. by 8 in., was of a flattened ovoid shape, and consisted throughout of dense bone. After the removal of wax, the drum-head was seen to be nornmal, and the mastoid process to be of the pneumllatic type with a large antrum separated by a shell of bone from the sinus; all mastoid cells were removed, and in lining the large cavity created Hugh Jones's flap was found very convenient to manipulate owing to its long and flexible pedicle; it is suggested that the flap might with advantage be split longitudinally in order to furnish eight growing epithelial edges. Photographs were shown for the purpose of emphasizing the advantage of stereoscopic over ordinary photography for demnonstration purposes.