=Indications.= It is especially useful for the enlargement of the socket by the formation of new fornices. As a rule it is performed for the reproduction of the lower fornix, as it is frequently due to the obliteration of this cul-de-sac that the artificial eye cannot be retained. The operation, however, may be modified and applied to the formation of both the upper and outer culs-de-sac. =Instruments.= Scalpel, forceps, scissors, and sutures. =Operation.= A general anæsthetic is required. _First step._ An incision is made in the lower fornix throughout its whole length and carried downwards for a distance of about half an inch (Fig. 137, A). _Second step._ A crescentic piece of skin is marked out on the lower lid by two incisions which have their concavity directed upwards. The upper one is parallel with the margin of the lower lid and about 5 millimetres below it. This crescentic flap is then dissected up from the deeper tissues all round, except for a small pedicle at its centre (Fig. 137, B). _Third step._ The incision forming the upper margin of the crescentic piece of skin is deepened until it meets the incision made in the fornix, so that the lower lid is converted into a band of tissue attached only at each end. [Illustration: FIG. 137. MAXWELL’S OPERATION FOR CONTRACTED SOCKET. _First step._ A is the incision through the conjunctiva. The flap of skin from the outer surface of the lower lid is entirely raised from the subcutaneous tissue, except for the pedicle B which holds the new fornix in position.] [Illustration: FIG. 138. MAXWELL’S OPERATION. _Final step._ Showing the flap of skin from the outer surface of the lower lid turned in to form the new lower fornix. The surface wound has been closed by sutures.] _Fourth step._ The upper margin of the incision in the fornix is stitched to the upper margin or concavity of the crescentic piece of skin after the latter has been displaced upwards beneath the band of tissue carrying the lashes, and the lower margin of the crescentic piece of skin is stitched to the conjunctival edge of the band, so that the crescentic piece of skin is folded on itself and forms the new lower fornix, being held down in its position by the pedicle (Fig. 138). The sutures should be of catgut, as their subsequent removal is somewhat difficult. _Fifth step._ The surface wound is closed by silkworm-gut sutures. The socket should be packed with gauze, or else a piece of style wire should be inserted, as in the previous operation, so as to maintain the groove in the new lower fornix. CHAPTER VIII OPERATIONS UPON THE EYELIDS SURGICAL ANATOMY The eyelids consist of well-marked planes of tissue, which are, from without inwards-- 1. Skin with very little subcutaneous fat. 2. Orbicularis muscle. 3. Tarsal plates, which are attached to the orbital margins by the palpebral ligaments and which thereby form a barrier to the passage of infection backwards into the orbit.