Fig. 147. Arlt’s Operation for Trichiasis.
Arlt’s operation. Indications. The operation is suitable for cases of trichiasis in which part or the whole of the lashes of the upper lid turn inwards and rub on the surface of the cornea.
Instruments. Beer’s knife, forceps, scissors, sutures, lid clamp.
Operation. First step. A lid clamp is applied to the upper lid. An incision is made in the intermarginal line and the tarsal cartilage is split behind the lash-bearing area for a depth of about 5 millimetres throughout the whole extent of the lid (Fig. 147).
Second step. An incision through the outer surface of the lid above the lashes is made to meet the other at right angles, so that the lashes are carried on a band of tissue attached at each end.
Third step. A semilunar piece of skin is then removed by a curved incision above the last, joining it at the outer and inner ends, and the band carrying the lashes is stitched to the upper margin of this incision; the line of the incision along the intermarginal zone behind the lashes is allowed to heal by granulation. The subsequent contraction caused thereby pulls down the band carrying the lashes to a certain extent. It is, therefore, desirable to pull the band of lashes upwards at the time of operation to a greater extent than is required for the final result in order to overcome this tendency for the condition to re-form as a result of cicatricial contraction of the granulating area. In order to obviate the cicatricial contraction some surgeons cover the area with a graft of mucous membrane.
ECTROPION OPERATIONS
Ectropion may affect the upper lid, but it occurs far more frequently in the lower. Operations undertaken for its relief vary very considerably for the following reasons:—