4. When in a case of chronic purulent frontal sinusitis there is pain and fever with a fœtid discharge.

5. Persistent headache, particularly when associated with discomfort in the region of the eye, and not relieved by intranasal treatment.

6. When the discharge from the sinus remains foul, in spite of repeated irrigations.

7. When recurring groups of polypi are produced by the suppuration in the frontal and ethmoidal cells.

8. When a simple purulent discharge is not relieved by careful intranasal treatment, and the patient desires permanent relief by radical operation.

A radiograph is taken and is an extremely useful help to indicate the size and extent of the frontal sinus, and to prepare the surgeon for meeting with troublesome orbito-ethmoidal cells.

As the ethmoid is diseased in nearly all cases it should be cleared away at previous sittings, under cocaine or chloroform (see [p. 615]). Even when healthy, the anterior extremity of the middle turbinal should be amputated (see [p. 592]). If the antrum be also suppurating and a suitable tooth socket be available, the alveolus will have been drilled at one of these preliminary treatments. If the sphenoidal sinus be suppurating, its orifice will have been enlarged.

One hour before the operation the strips of ribbon gauze, soaked in adrenalin with the addition of 5% cocaine, are carefully laid all over the mucous membrane of the nose on the affected side. The face, moustache, and beard are well purified. When the patient is under chloroform three pencils of tightly rolled cotton-wool are introduced into the nose; one along the middle meatus, a second in front of the inferior turbinal upwards towards the bridge of the nose, and the third in the inferior meatus. The first two pledgets are useful afterwards for anatomical definition, and the third keeps them in place. A sponge is inserted in the post-nasal space (see [p. 575]).

Operation. There is no advantage in shaving off the eyebrow. It can be thoroughly purified and helps to locate the skin incision; if removed, it takes some time to grow again, and is apt not to correspond in size with the eyebrow of the opposite side. The skin incision is first defined by scratching through the cutis with the tip of the knife. It starts at the outer end of the eyebrow, passes inwards along the very centre of the eyebrow itself, and then sweeps downwards and outwards over the side of the nose, to end on the cheek (Fig. 336). When the whole extent has been marked out three or four cross scratches are made. The object of this is to ensure correct coaptation of the flaps, and to avoid any risk of disfigurement. Returning to the outer extremity of the incision, it is now carried down through all the soft tissues till it meets the periosteum. The flaps are retracted a little upwards and downwards, while the free hæmorrhage is met with pressure forceps. The periosteum incisions are now carefully planned. Starting again from the outer corner the knife is drawn inwards parallel to, and slightly above, the upper margin of the supra-orbital arch; but, instead of curving round the inner end of the orbit, in the track of the skin incision, it is kept straight along under the upper flap to end over the glabella. The periosteum can now be reflected from the front of the sinus, and pushed upwards with the skin on to the forehead. The lower skin flap is detached and retracted downwards, until the inner third of the supra-orbital arch is defined. The periosteal covering is next cut through by carrying the knife along the lower border, but instead of passing inwards parallel to the first periosteal incision this second one sweeps down on to the side of the nose, in the track formed by the skin incision (Fig. 337).

Fig. 336. Killian’s Operation upon the Frontal Sinus. Shows the skin incision, with the transverse scratches made to ensure correct coaptation of the flaps.    Fig. 337. Killian’s Operation upon the Frontal Sinus. The thick lines indicate the incisions through the periosteum.