Fig. 235. Ballance’s ‘Stopper’ for pushing in the Graft.
Fig. 236. Pipette for sucking Air and Fluid From beneath the Graft.
Fig. 237. Skin-grafting of Mastoid Wound Cavity after Operation. Skin graft in the act of being sucked into position by the pipette.
A glass pipette (Fig. 236), having a curved beak, is then passed inwards beneath the graft until its point, directed downwards, lies within the tympanic cavity (Fig. 237). Any blood which has accumulated between the bone and the graft is now sucked out, and in doing this the graft becomes closely applied to the bone surface (Fig. 238). After removing the pipette, any part of the graft which is not adherent to the bone is smoothed out over its surface. The tympanic cavity and the innermost portion of the mastoid cavity are then plugged with sterilized pellets of cotton-wool wrapped in gauze and dusted with aristol powder. The outer portion of the cavity is filled up with a strip of gauze, its end being brought out through the external auditory meatus.
| Fig. 238. Skin-grafting of Mastoid Wound Cavity after Operation. Skin graft in position. |
| Fig. 239. Posterior Portion of Skin Graft covering Outer Surface of Wound Cavity. |
The posterior part of the graft, still projecting beyond the posterior margin of the wound, is now turned forwards so as to form a covering over the gauze filling up the wound cavity (Fig. 239). On the auricle being restored to its normal position, this portion of the graft is brought into contact with the subcutaneous tissues of the skin forming the post-aural flap, which now forms the outer wall of the mastoid cavity. The posterior incision is closed with sutures and a dry dressing and bandage are applied to the ear.
If skin-grafting be performed a week or more after the primary operation. The post-aural wound, now healed, has to be reopened. In doing so there may be considerable bleeding, which must be arrested. The mastoid cavity is usually found to be covered with a fine layer of granulations. They are curetted away carefully, special attention being paid to the region of the Eustachian tube and the floor of the tympanic cavity. After removal of the granulations, the bone should appear uniformly smooth though somewhat vascular. If any points of carious bone be found they should be removed freely with the gouge or burr. Considerable time may have to be spent in arresting the oozing from the surface of the bone cavity. This is best done by washing out the cavity with hydrogen peroxide solution and then plugging it tightly for a few moments with adrenalin solution. The gauze is withdrawn in a few moments. If there be still oozing, the pressure will have to be repeated until it ceases. The method of applying the graft is the same as already described.