Modified Iridotasis Operation in Glaucoma


Modified Iridotasis Operation in Glaucoma. The conjunctiva is gently replaced and, if all the operative area is well covered and if moving the upper lid up and down a few times does not disturb the flap, sutures may be dispensed with, though often one or two may be found necessary. If there is a return of tension on the second or third week, as sometimes happens, massage and temporary use of myotics have in my experience always tided over this period.


AS AN introduction to this paper I can do no better than quote extensively from an editorial by Edward Jackson in the February American Journal of Ophthalmology. He has expressed so clearly my deepest convictions in regard to this subtle disease, which has too often ended in blindness for the want of early recognition or of a properly regimented care.

“Glaucoma has been defined as increase of intra-ocular tension, with the causes and effects of that increase; a very good definition of the word. It is not certain that a better definition can be given today. It fixes attention on the central fact-increased intra-ocular pressure. But of the essential causes of such increase we still have only guesses, speculations, and unproved hypotheses.

“The successful operations that have been done for glaucoma, scleral tapping, anterior or posterior sclerotomy, iridotomy, incision of the ciliary body, cyclodialysis, Lagrange sclerectomy, Elliot trephining, iris inclusion, or iridotasis, present a confused picture.

“Knowledge of the effects of glaucoma has convinced all that it is a serious disease, that it is dangerous to neglect; but inclines one to think that little can be done to prevent the disastrous result. Without the stimulus of hope, we are not likely to put forth our best efforts.

“Some cases of glaucoma recover without treatment, some reach a permanent recovery after the use of miotics. If these cases were all reported with the same minute detail as we use to report the pathologic changes in the eyes that have to be enucleated, glaucoma would not be regarded as always hopeless.

“When a case does get well, it is apt to be regarded with doubt as to the permanence of the cure, or the correctness of the diagnosis. In the use of Laquer, glaucoma was held in check by miotics for more than five years; and then cure by operation gave good vision, which continued for more twenty years, to the end of his life”.

In this one sentence describing the case of Laquer, is embodied the ideal for which we are all striving. How to obtain this result is the question about which has received all the controversy of preoperative care, methods of operative procedure and postoperative regimen. Rules of procedure cannot always be followed, due to extenuating circumstances surrounding many cases and because of the inability to obtain consent to operate at the time of election. However, I feel that any case in which the fields of vision and the degree of tension cannot be kept in safe bounds by instillation of miotics four time a day, should be persuaded to resort to some operative procedure.

The patient or relatives responsible for their welfare should be taken in confidence and be made answerable for any delay. On the other hand the risks of operation should not be minimized but the greater danger of postponement should be properly stressed. When this has been settled, the grave decision of choice of procedure falls to the surgeons lot. The fact that there are so many methods, with their numerous modifications, is proof that no one of them is always satisfactory at the moment or in the later results.

If it often stated “that operation with which you are most confident of results is the operation for you,” but is not this confidence but the product of ones personal experience, subject to the peculiarities of each case and the familiarity with the technic used? However, as perfection is never attained, one is justified in constantly weighing each new operative method in the light of difficulties found in the old.

During twenty-eight years of experience I was bound to develop certain definite opinions, which may have been due only to my personal temperament or to the circumstances surrounding the care of certain cases. For example, after seeing a number of operators do the cyclodialysis operation and after becoming enthusiastic about this procedure as I witnessed it in Millers clinic in Vienna, I tried it out on my return in 1924. Two cases had marked reaction with increased tension just after operation, and another too soon had to be re-operated. The fault may have been mine, but I cannot help having had an aversion for this procedure ever since.

Though I have done many iridectomies with excellent results, especially in the first year of practice, I am still convinced that to place the incision in the proper angel at the root of the iris is most difficult. This dis almost impossible with a very shallow anterior chamber and an eyeball under high tension, unless a posterior sclerotomy is a first resort. This led me to be most enthusiastic over the Elliot trephine, but a number of large hideous- looking blebs and one infection four years after operation forced me to conclude that the perfect procedure was still to be found. Lagrange with scissors or punch has often been very successful; however, some cases have too long a postoperative inflammatory stage to give the greatest feeling of security.

Some years back I became enamoured with the iridotasis operation for mild inflammatory and especially non-inflammatory types of glaucoma. It was easily done and seemed all that could be desired. In older cases where the iris is thin and atrophic this operation does not always produce sufficient drainage since the scleral scar closes this newly formed outlet. In order to prevent this and to make the operation applicable also to he more severe types of this disease, I have resorted to punching out piece of sclera from the edge of the wound before drawing the iris between its edges.

The operative technic is as follows: A horizontal conjunctival incision about 12 mm. in length is made about 8 mm. above the cornea. This is dissected down toward the corneoscleral junction, being sure to get all the tissues down to the sclera in the lower center of the flap, in order that the punched-out area will have sufficient covering and remain loosely overlying for good absorption of seeping aqueous. Then at the center, close to the cornea, a scratch incision with a Graefe cataract knife is slowly made, trying to keep each scratch the same depth. The scratch is about 5-6 mm. in length and so placed that it enters the anterior chamber near the root of the iris. Eventually some point will prick through and a few drops of aqueous appear.

Thus the tension is gradually lowered and the incision enlarged by knife or scissors. It length should be only long enough to allow the grasping of the iris near the pupillary margin. Next the punch, thin side down, is pressed under the edge of the sclera at the center of the wound and a piece punched out. The size of the punched-out area depends, as in the trephine or Lagrange operation, upon the judgment of the operator. The iris is now grasped with small curved forceps as near the pupillary margin as possible and gently withdrawn with pigment side uppermost. This is now left with the center filling the gap in the sclera made by the punch.

The conjunctiva is gently replaced and, if all the operative area is well covered and if moving the upper lid up and down a few times does not disturb the flap, sutures may be dispensed with, though often one or two may be found necessary. If there is a return of tension on the second or third week, as sometimes happens, massage and temporary use of myotics have in my experience always tided over this period. As you see, I have by this procedure attempted to make the iridotasis operation adaptable to all forms of glaucoma. The incision is easily made without danger of injuring either the ciliary body or crystalline lens. As neither the root of the iris nor the iris itself is incised there is little trauma to delicate tissues prone to prolonged reaction. Lastly, it produces the greatest amount of drainage with the minimum danger of secondary infection.

I shall now briefly report the four worst cases I have seen of late years and the results obtained by this method.

CASE REPORTS.

Mrs. M.E.; she had received a traumatic injury of left side of head in June, 1931. Was unconscious for two to three days, after which she had intense pain and blindness in left eye. Pain and blurred vision developed in right eye. Was treated at another hospital, where left eye was operated on in March of the following year. As both eyes were worse after the operation, she would not give her consent to have the right eye operated on and she left the hospital against advice. Later was led into the Homoeopathic Dispensary with both eyes in state of acute inflammatory glaucoma. The right eye had tension of 65 McLean, with small pupil, very shallow anterior chamber and marked injection of the conjunctiva of both eyeball and lids. The left and a tension of 75 and the iris was tangled up in a mass of exudate and broken-down less substance.

Apparently, an operative traumatic cataract was present. There was a chemosis of the bulbar conjunctiva and a superficial ulceration at the center and edges of the cornea at three oclock. The latter was probably due to the attempt of the patient to instil drops is her own eyes. Intense pain and blindness had again led the patient to seek aid at a hospital. The previously described operation was done on the right eye on May 7, 1932. As I could not obtain consent to enucleate the left eye, I was forced to attempt to save what I could.

William M Muncy