[Illustration: FIG. 60. THE AUTHOR’S METHOD OF COVERING IN A GAP IN THE SKULL. _s._, The scalp; _pc._, The pericranium; _p._, The plate; _g._, The gap in the skull (inside the irregular dotted line); _sc._, The scalp-flap.] The plate is then boiled and applied as follows. The osseous defect is exposed by a scalp-flap--not including pericranium--the margin of the scalp-flap lying _at least 1 inch_ external to the margin of the gap.[37] The flap is dissected down so that its base is situated _not more than ¹⁄₂ inch_ below the lower limit of the gap. The pericranium is then stripped away towards the periphery. The plate is applied so that it rests below against the base of the scalp-flap, lies throughout between the scalp and bone, and overlaps the margins of the gap by about ¹⁄₂ inch. The pericranium is heaped up around and over the margins of the plate, and the scalp-flap replaced. The plate is maintained in position by the support received from the base of the flap, marginally by the pericranium, and generally by the reposition of the scalp-flap.[38] In the process of time, new bone is formed by the pericranium, this and fibrous tissue developing along the line of the scalp incision fixing the plate accurately and firmly in position. Needless to say, absolute sterility of the field of operation and of all media is essential. In the event of failure in cleanliness, however slight, it will become necessary to reopen the wound and remove the plate. In such cases a second attempt may be made at a later date. =Results.= The results attained by operative treatment must always be considered under two headings: the immediate and the more remote. The immediate results are almost always of a satisfactory nature, the fits being more or less completely controlled, or so diminished in quantity and quality as to satisfy both surgeon and patient. Such early results may be regarded as the general rule, and some enthusiasts believe that the ultimate results are equally satisfactory. However, in following up these cases, it will be found that, in a considerable proportion of cases, the more remote results are by no means so satisfactory. A complete and permanent cure is seldom obtained, though the great majority of cases evidence considerable improvement, the fits recurring, though less frequent and less intense than previous to the operation. The results which may be obtained should therefore be considered as follows:-- Cases of complete and permanent cure. Cases of definite amelioration. Cases in which no benefit is derived. In 20 cases that have come under my own care, the following results were obtained:-- Complete cure in 2. Marked improvement in 14. No change in 4. Cushing reports on 128 cases of traumatic epilepsy, operative measures being adopted in 58, 40 cases of focal epilepsy and 18 exhibiting no localizing feature. The results were as follows:-- 12 cases were free from attacks for from 1 to 5 years.