After the antrum has been exposed, the technique of the operation is the same as that already described in the Schwartze and Kuster-Bergmann operation.

=Advantages.= 1. If the surgeon be experienced it saves much time, as the preliminary steps of the operation can be carried out very rapidly.

2. If the mastoid be sclerosed and there are no landmarks, the antrum, however small, is bound to be reached by making use of this method, by keeping high up, and, if necessary, exposing the dura mater. To verify the depth to which the bone may be removed and also the position of the antrum, the seeker should be inserted occasionally through the tympanic cavity into the aditus.

=Disadvantages.= If the surgeon be not experienced, it is not so safe a method as that of first exposing the antrum.

=Stacke's operation.= After exposure of the field of operation, as in the Kuster-Bergmann operation, the fibrous portion of the auditory ca.n.a.l is separated posteriorly from the bony portion.

[Ill.u.s.tration: FIG. 226. WOLF'S OPERATION.]

Any granulations, together with the malleus and incus, are removed from the tympanic cavity (see p. 353). Under a good illumination, using a head-lamp if necessary, the surgeon pa.s.ses a seeker along the auditory ca.n.a.l, its point being made to project into the attic in order to define its limits and that of the aditus. The innermost portion of the upper posterior wall of the auditory ca.n.a.l, that is, the outer wall of the attic, is now removed piecemeal by means of a small gouge (Fig. 227). By working backwards the aditus is approached, the bone being removed carefully in small fragments. The seeker is inserted repeatedly into the entrance of the aditus so as to rest on the external semicircular ca.n.a.l, in order that the position of the latter and the underlying facial nerve may be kept constantly in mind. More bone above and external to this point is removed in small fragments, until at length the upper and innermost portion of the antral wall is removed and its cavity thus exposed. The cavity is gradually enlarged by removing still more bone in a backward and outward direction, until finally it resembles that left after the complete operation. Stacke originally devised this method in those cases in which he considered that the disease was limited to the ossicles, the walls of the attic, aditus, and innermost portion of the antrum. It was, indeed, merely a more radical method of performing ossiculectomy.

=Advantages.= Although this operation has practically been abandoned as a method of performing ossiculectomy, yet under the following conditions it may be adopted during the performance of the complete operation:--

1. If the mastoid be very sclerosed and if the antrum cannot be exposed, although the bone has been removed to a depth corresponding to its usual position.

2. If there be difficulty in exposing the antrum in the performance of the radical operation owing to the lateral sinus projecting far forwards and the middle intracranial fossa overlapping it externally.

=Disadvantages.= The chief disadvantage is that it is more difficult and tedious to begin the operation within the depth of the wound, and if the meatus is very deep and narrow it may be almost impossible to carry out.

=Preservation of the ossicles and tympanic membrane after performing the complete mastoid operation.=

This method of operation is well known and has been performed for some years, especially by Jansen of Berlin, and in America.

[Ill.u.s.tration: FIG. 227. STACKE'S OPERATION.]

The only indication for this modification of the complete mastoid operation is disease involving the antrum and mastoid process so extensively as to require complete removal of the posterior wall of the auditory ca.n.a.l, without there being any coexisting bone disease of the walls of the attic or of the ossicles.

As the complete mastoid operation is only performed for some condition due to chronic middle-ear suppuration, it is difficult to imagine that the ossicles and attic region could remain unaffected when the extent of the disease necessitates the complete operation.

In my opinion, if it be necessary to remove the 'bridge' it is also necessary to remove the outer wall of the attic and with this the malleus and incus. If, on the other hand, there be no bone disease of the attic region or of the ossicles, Schwartze's operation, or some modification of it, should be sufficient. The majority of aurists agree that, excepting in those cases in which the continuance of the suppuration is due to an empyema of the antral cavity, the ossicles are almost invariably carious to a greater or lesser extent in chronic middle-ear suppuration. This view is supported by Grunert's researches (_Archiv fur Ohrenheilkunde_, Band 40), who found that the ossicles were only normal in five cases in a series of 113 cases in which the complete operation had been performed.

[Ill.u.s.tration: FIG. 228. POST-MEATAL SKIN FLAPS (_Author's method_).

Bistoury incising the posterior fibrous portion of the auditory ca.n.a.l.

The dotted line shows the line of incision. A is the Y-shaped flap afterwards sutured to the skin behind the auricle.]

Although removal of the 'bridge' may eradicate the disease within the mastoid process and antrum, yet, if the ossicles are left, post-suppurative adhesions will almost certainly afterwards bind them down and so cause a greater deafness than if they had been removed originally. Still, a few isolated cases have been reported in which hearing to the extent of 20 feet or more has been obtained as the result of this operation. The same results, however, frequently occur after the performance of the complete operation with removal of the malleus and incus. Until we have a large and consecutive series, recording the results of this particular operation in detail, together with information regarding the duration of the symptoms, the previous treatment, and the condition of the ear before operation, it is impossible to judge the value of this method.

THE FORMATION OF POST-MEATAL SKIN FLAPS

This is done for two reasons: firstly, to prevent stenosis of the auditory ca.n.a.l; and secondly, to aid the growth of the epithelium over the wound surface, so that the latter will heal as rapidly as possible.

These flaps may be formed in several different ways. The following is the technique I adopt: A long, narrow, curved bistoury is pa.s.sed down the auditory meatus so that it projects through the detached end of the fibrous portion, its point being directed backwards. The auricle is held well forward and the fibrous portion of the meatus cut through posteriorly, from within outwards, for a short distance (Fig. 228). The edge of the bistoury is then directed in a slanting direction upwards and outwards, and the incision continued as far as the cartilaginous portion of the meatus, care being taken not to cut into the concha. The bistoury is then withdrawn and reinserted at the point at which it was first made to turn upwards. It is now directed downwards and outwards and, in a similar manner, the incision is made in a slanting direction towards the inferior margin of the cartilaginous meatus. In carrying out these manipulations care must be taken that the outer portion of the bistoury does not injure the tragus or other portion of the auricle, a mistake which can easily occur. The fibrous portion of the meatus is thus divided by a Y-shaped incision into three small flaps; namely, a posterior or external V-shaped flap, and a superior and an inferior flap (Fig. 229).

[Ill.u.s.tration: FIG. 229. POST-MEATAL SKIN FLAPS (_Author's method_).

Flaps cut: A, Y-shaped flap sutured to the skin; _b_, Superior flap; _c_, Inferior flap.]

The outer flap is fixed to the skin behind the auricle by means of a catgut suture (Fig. 230), and the auricle is then pulled back into its normal position. By inserting the tip of a finger into the meatus, the upper and lower flaps are pressed upwards and downwards against the roof and floor of the mastoid cavity, and can be kept in position afterwards by suturing the flaps to the subcutaneous tissue or by packing the cavity through the meatus with a strip of ribbon gauze.

Amongst other methods the following may be mentioned:--

=Korner's method= (Fig. 231). Two parallel incisions are made in a longitudinal direction through the fibrous portion of the posterior wall of the meatus and are prolonged outwards as far as the concha. On the auricle being restored to its normal position, this posterior flap is pressed backwards and so covers a large area of the posterior wound surface. The chief objection to it is that, owing to involvement of the concha, there is considerable enlargement of the meatal opening and therefore subsequent disfigurement.

[Ill.u.s.tration: FIG. 230. CLOSURE OF WOUND AFTER 'RADICAL' MASTOID OPERATION. A is the point at which the Y-shaped meatal flap is sutured to the skin.]

=Panse's method= (Fig. 232). A transverse incision is carried through the posterior margin of the meatus, at the junction of the concha and auditory ca.n.a.l posteriorly. With a pair of scissors or knife, the posterior wall of the fibrous portion of the ca.n.a.l is now split by a longitudinal incision. In this way two flaps are formed, a superior and inferior one. They are fixed into position by catgut sutures through the subcutaneous tissues at the upper and lower angles of the wound.

=Stacke's method= (Fig. 233). This consists of a large inferior flap, formed by making a longitudinal incision along the posterior upper border of the fibrous portion of the auditory ca.n.a.l and a transverse incision meeting it at right angles, the latter cutting through the fibrous portion of the meatus at its junction with the concha.

In order that these flaps may be thinner and more adaptable, the subcutaneous tissue should be cut away. Of these flaps the Y-shaped one is the most practicable, as it is suitable whether the posterior wound is closed or left open.

[Ill.u.s.tration: FIG. 231. KoRNER'S POST-MEATAL FLAP.]

[Ill.u.s.tration: FIG. 232. PANSE'S POST-MEATAL FLAP.]

[Ill.u.s.tration: FIG. 233. STACKE'S POST-MEATAL FLAP.]

Korner's method has the objection that there is subsequent disfigurement owing to the large meatal opening formed by cutting into the concha. It has the advantage, however, that the large posterior flap will cover the posterior surface of the wound cavity to a considerable extent, and also that it will permit a good view of the surface.

Panse's flap is only of service if the posterior wound is left open and if there is not sufficient tissue left to make a posterior flap owing to previous destruction of the posterior wall of the auditory ca.n.a.l.

Stacke's method is good if skin-grafting is afterwards employed.

CLOSURE OF THE WOUND

Excepting under the conditions mentioned below, the posterior wound is closed by bringing together the edges of the skin incision with fine silkworm-gut sutures (Fig. 230). Before this is done, the wound cavity should be irrigated with a weak solution of biniodide of mercury, dried, and the deeper parts of the wound plugged with a strip of gauze inserted through the external meatus. This will not only arrest the haemorrhage and keep the inner part of the wound dry, but at the same time will keep the skin flaps in position. After the wound has been closed, firm pressure should be applied in front and behind the ear to press out any blood from the cavity.

As a final step the gauze which has been inserted into the meatus is removed, and the cavity again packed evenly and lightly from the bottom of the wound with a fresh strip. The ear and surrounding parts are protected with a pad of sterilized gauze covered with cotton-wool and kept in position with a bandage.

_The posterior wound should be left open under the following circ.u.mstances_:--

1. If there be an abscess over the mastoid process. Although it may be possible to excise the whole of the lining membrane of the abscess cavity, it is wiser to leave the wound open for the first few days. The innermost portion of the wound cavity is packed through the external meatus, only the superficial part being packed through the posterior wound incision. As healthy granulations appear, the posterior packing is diminished, so that the edges of the incision gradually come together.

If necessary, the edges of the wound can also be freshened and brought together by silkworm-gut sutures under cocaine anaesthesia.

2. If there be extensive disease of the bone, especially if the dura mater and lateral sinus are covered with septic granulations.

3. If there be bone disease of the anterior and inferior parts of the tympanic cavity. The after-treatment of packing or the curetting away of granulations can be carried out more easily through the posterior wound than through the external meatus, as it gives a better view of these regions.

4. In young children it is frequently advisable to leave the posterior wound open owing to the difficulty of packing the wound cavity through the small external meatus.

SKIN-GRAFTING AFTER THE MASTOID OPERATION

In order to shorten the duration of healing, a large Thiersch's skin graft may be transplanted into the wound cavity. If this procedure be adopted it may be carried out in several ways. The skin may be transplanted in one large piece or in several small portions, and it may be introduced into the wound cavity either immediately after the completion of the mastoid operation or from seven to ten days later.

There is considerable diversity of opinion as to whether skin-grafting should be employed or not, and also when it should be done.