GLAUCOMA.
The treatment of Primary glaucoma—i.e., that form of increased tension in the globe not preceded by any intra-ocular disease—requires prompt measures when occurring in the acute form. Myotics and Iridec tomy are the methods to be resorted to; the choice of these agents will depend upon the special indications present, but as a rule removal of a portion of the iris must be effected if a permanent result is to be obtained. Eserine should be instilled immediately as soon as the first symptoms of the disease exhibit themselves; the solution should not be stronger than 2 grs. to r oz. Posey recommends that as a strong solution of Eserine may cause spasm of the ciliary muscle Pilocarpine should be at first employed, but this is of more importance in chronic attacks, since time is of vital importance in the acute type of the affection in order to prevent total blindness from retinal destruction. The instillation should be repeated 3 or 4 times within the first hour, and at longer intervals after wards. A strong Saline purgative should be administered, and the local tension may he lessened by leeching; hut all these measures must be regarded as mere palliatives, and should only he resorted to as preliminary procedures to preserve the integrity of the eye while awaiting the neces sary arrangements for the performance of an iridectomy. Even should the attack appear to pass off the operation should be carried out, as recurrence is almost certain to supervene and the vision may be com pletely destroyed before aid can be again obtained.
The incision should be made as far back in the cornea-sclerotic margin as possible, and Swanzy insists that at least one-fifth of the circumference of the iris should be removed as close to the root as possible, and that the aqueous humour be permitted to flow away very gradually in order to avoid intra-ocular hmorrhage from the suddenly reduced pressure. If the operation should by any means fail to reduce the tension, posterior sclerotomy must be resorted to in order to restore the anterior chamber and permit the lens to resume its normal position. Henderson explains
the efficacy of iridectomy upon the theory that the aqueous humour escapes into the stroma of the iris through the incised lips of the wound made in it, as no cicatrisation occurs in them. In rare intractable cases Lagrange's combined iridectomy and sclerotomy operation which estab lishes a subconjunctival fistula may be resorted to, and Herbert's modifi cation of iridectomy is planned upon similar lines to secure continuous escape of a small quantity of the aqueous humour into the lymph spaces of the episcleral tissue.
Subacute or chronic primary glaucoma is to be treated upon similar lines. In many cases the tension may be kept normal by the continual use of Eserine, but the instillation must be kept up during the remainder of the patient's life, and often irritation of the conjunctiva becomes unbearable. The dietary and alimentary canal will require close super vision; every agent tending to produce increase in the general blood pressure must be neutralised. Maddox recommends periodical manipu lation of the eyeball. As a rule it is wiser to perform iridectomy and thus forestall a severe acute attack, but the excellent effect as regards gain or restoration of sight which follows the operation for acute glau coma is not to be expected in the chronic form, since in these cases the vision is always more or less permanently damaged.
In chronic gouty glaucoma success often follows the medical treatment of the primary disorder without resorting to operation.
The operation of removal of the superior ganglion of the sympathetic has been many times performed for chronic glaucoma, but not always with success. Many surgeons advocate a simple sclerotomy to evacuate the aqueous without removing any iris.
Congenital hydrophthalmos, or as it is also called cornea globosa and buphthalmos, when the tension becomes greatly increased in the dis tended globe is best treated by Eserine instillations; operative procedures are contra-indicated as a rule.