Operations Other than Scleral Trephining for the Relief of Glaucoma
BY
Casey A. Wood, M.D.,
Chicago.
In this paper I shall say a few words about the large number of operative procedures that, apart from trephining, or, preferably, trepanation, have been urged in the treatment of the various forms of glaucoma. Their name is legion and among them we find peripheral iridectomy; anterior sclerotomy; irido-sclerotomy; scleriritomy; de Wecker's dialysis of the iris; Hancock's division of the ciliary muscle; the incision of the iridian angle of de Vincentiis; sclero-cyclo-iridic puncture; the Sterns-Semmereole sclerotomia antero-posterior; the transfixio iridis of Fuchs; Antonelli's peripheral iritomy; Holth's formation of a cystoid cicatrix; Hern's operation; Terson's sclero-iridectomy; Abadie's ciliarotomy; Ballantyne's incarceration of iris method; Masselon's small equatorial sclerotomy; Simi's equatorial sclerotomy; Galezowski's sclero-choriotomy; excision of the cervical ganglion; removal of the ciliary ganglion; Querenghi's operation of sclero-choriotomy; Bettremieux's simple anterior sclerectomy; Heine's cyclodialysis; Herbert's wedge-isolation operation; Verhoeff's operation with a special sclerotome; Holth's sclerectomy with a punch-forceps; Walker's hyposcleral cyclotomy; posterior sclerotomy; T-shaped sclerotomy; and last but not least the Lagrange form of sclerectomy with its various modifications by Brooksbank James, myself and others.
In addition to the foregoing list—which is by no means complete—there are several combinations of operations, as, for example, the Fergus trephining operation, which is really a combination of a sclero-corneal trepanation and a cyclodialysis.
So far as it is practicable there is a certain amount of wisdom in comparing the results of an operative procedure with others with which it is brought in competition, and I believe we are even now in a position to form at least some idea of the comparative value of the three methods that comprise the great majority of interventions made use of by ophthalmic surgeons at the present time. I refer to iridectomy, the Lagrange operation, and the Elliot operation. So far as regards the last named procedure, I congratulate this Society that it has had an opportunity of seeing a demonstration and hearing a discussion by the famous ophthalmic surgeon who perfected it.
As regards the others let me recommend to you the complete description of them given by Posey in A System of Ophthalmic Operations.
Let us consider the first of the three procedures just mentioned—iridectomy—introduced by von Graefe. The mechanism of its mode of cure is best studied in cases of acute primary glaucoma, when there is apposition of the periphery of the iris to the cornea. In these acute cases there is probably only a mere apposition, and the blocking up of the sclero-iridian angle is largely mechanical. Here the root of the iris is readily removed in its entirety and a really peripheral iridectomy is easily done. When, however, a true adhesion between corneal and iridic tissue takes place the filtration angle is not so easily opened. True peripheral adhesions are not readily broken up or separated, and the iridectomy is, for that reason at least, not effective. Moreover, this form of anterior synechia (resulting from a true union of iris and cornea) is so intimate that the iris root is, by the iridectomy, torn away only at the sclero-iridian angle at the anterior border of the adhesion—and does not open up a channel into Schlemm's canal. It is not, therefore, difficult to understand why iridectomy alone in any of the forms of chronic glaucoma fails to open up the true filtration spaces and does not provide a drain that permits of an escape of fluid from the posterior chamber through the loose tissue that surrounds it into the canal of Schlemm. Treacher Collins found, after a careful examination of eyes upon which iridectomy had been performed for glaucoma, that it is extremely rare for the initial section to pass through the pectinate ligament, while Schlemm's canal invariably escapes. Moreover, since the sclero-corneal incision is uniformly oblique, the position and extent of the external wound does not always furnish evidence of the character of the internal wound. In all likelihood many cases of relief or cure following iridectomy are those due to the formation of cystoid scars or minute fistulae, rather than as a result of the removal of a portion of the iris periphery.
The best brief tabulation of the results obtained by iridectomy, in glaucoma, is to be found in Weeks' textbook on Diseases of the Eye, page 417: "Sulzer reports as follows: Acute glaucoma, 149 cases; improved, 72.5 per cent; serviceable vision preserved, 11.3 per cent; vision impaired at once, 4.08 per cent; very little vision, 12.12 per cent.