VOL. VIII

10/032

THE

RELATION BETWEEN GENERAL ARTERIAL SCLEROSIS AND INCREASED TENSION IN EYEBALL.

Some Practical Observations on the Use of the Schiötz Tonometer.)

BY WALTER H. SNYDER.

[Read before the Eye, Ear, Nose and Throat Section of the Ohio State Medical Association, at Cleveland, May 11, 1911.]

No apology is necessary for presenting such an interesting, practical subject as any definite method of recording the variations in the intraocular tension other than digital palpation. Most of you recall, as do I, some curious instrument that was invented to take this tension in some graphic method, and only those who have attempted to use them can know how impossible of use they

were.

The Graefe-Saemich hand-book discusses this very interesting subject and it may also be looked up in Parsons' "Pathology." The trouble with all these instruments has been that they have been laboratory devices rather than clinical ones; and I think the whole profession has felt the need of some accurate method for determining the intraocular tension, other than the method by the fingers and recording it as "Tn +1, +2, +3." This method is entirely too inaccurate, for, while it is relatively easy to tell from day to day whether the tension has increased a shade or decreased, there has been a demand for some method of recording tensions by which we could compare results gotten months before with something like the exactitude we have in the taking of the vision. This is especially true in the large number of cases of chronic simple glaucoma where a course of internal treatment has been instituted and where in all probability the results of this treatment would be better than an operation. It is therefore essential to have some method by which

we can from month to month have these cases come in, to determine, outside of their own feelings and conclusions, whether there has been an increase in tension or not.

When Professor Schiötz published his early articles on his tonometer in 1905, notwithstanding his successful practical work on the ophthalmometer, in conjunction with Javal, I felt this was another instrument which would not be of much practical aid. However, his modifications have certainly brought this instrument up to a high degree of efficiency, and a year's use of it has only taught me how very necessary it is.

I shall not give much time to a description of the instrument itself, as one can gain but little information from such a description. However, I will say that it is simplicity itself so far as its working qualities are concerned. The one I have in use was made and tested under Professor Schiötz's supervision; and I think it only fair that any criticisms of his instrument be made after using this instrument rather than some modification or possibly doubtful improvements and very often of inferior workmanship.

The objections which have been brought against this instrument are: First, the objections that patients may make to its use. To this I would answer that in a year's use among the most particular patients in northwestern Ohio, I have never had the slightest objection made about this being used, either on the first application or subsequently. Second objection, it is time-consuming. This is not an objection, as my assistant and I can take this tension of both eyes in two minutes, including the looking-up of the chart. Third objection, the instrument is so constructed that the weights drop off and the center piston falls on the floor. This I have never had happen and think that it is due to not recognizing the mechanical difficulty, which is easily overcome. The weights and center piston are held in by a bayonet catch. If only one-quarter turn is made after this is entered you will have no trouble; but with the perversity of inanimate objects if you attempt

to turn it several times round to insure its catching, one is certain to leave it in the position which will cause it to drop off. None of these objections are valid against its use and the only objection that can be raised against this method of tonometry is one which has nothing to do with the instrument itself; and that is that we have no means of knowing what the normal tension of the case we are testing is.

To explain this further, I mean that in a case in which we expect to find an increase of tension and find it to be 28, we have no means of knowing whether this is normal or abnormal. Schiötz says that the normal would vary between 15.5 to 25.0. One can easily see that if the normal of a patient was 18 and his tension was now 26, the diagnosis of hypertension would be more certain than if the normal was 22 and the same condition existed now. Unfortunately this doubt occurs in those cases in which we would like to depend most upon some mechanical means, e. g., those of primary simple glaucoma with but little cupping if any, and hardly an appreciable rise of tension as ascertained by palpation.

My technique is as follows, and I think it wise to adopt some method of doing it, that one may always get the same result. For instance, I use a solution of holocain 1%, rather than cocain, because of its supposed antiseptic action and its lessened deleterious effect on the corneal epithelium, besides probably affecting the tension less than the cocain, although I do not think this important. The main thing is to always use the same technique whatever it may be, thus insuring relative accuracy between one's own tests. After using this instrument we remove the weight, wipe it off and replace it in its place. The center piston is then washed in alcohol and allowed to dry thoroughly, the corneal cup and opening are thoroughly washed also with alcohol and allowed to dry. It is then put in the case and is ready for use on the next patient. I have not even used any special chair, the procedure being as follows: Two drops of the holocain solution are put in a few minutes apart, my assistant holds the patient's head, the latter looking up at the ceiling meanwhile; I then apply the instrument to the cornea and the number is read off. This can be done in one-half minute for each eye, with no pain or complaint from even the most nervous of patients, provided a certain dexterity is used, which is necessary in all operative procedures round the eye. The weights are numbered 5.5 gm., 7.5 gm., 10.0 gm. and 15.0 gm. These totals represent the weight of the rod, lever and the weight; the whole instrument weighs 12.0 gms. There is a

table of curves accompanying the instrument and one plots on that very readily the number of millimeters of mercury which corresponds to the reading of the instrument. I usually start with the smallest weight and then if the reading is anywheres between 3 and 6 consider it satisfactory; but if for instance it should be only 2, I would then put on the 7.5 gm. weight, which would register 5 or 6.

It has been especially useful to me in a large number of suspicious cases where I was not certain whether the diagnosis should be the beginning of chronic glaucoma or not. In these cases we have recorded the vision and will see them again in two or three months, thus having a very accurate record of not only the vision but the tension as well. I think it unnecessary to impress on you the fact that no one's fingers, with at most three or four divisions of tension, can be as accurate as this instrument, which can range from 15 mm. to a hundred; thus a most reliable and sensitive test is placed in our possession.

A number of interesting things have come out in the use of this instrument, especially as to the possibility of different drugs raising or lowering the tension. There is no question but that pilocarpin and eserin will reduce the tension, but whether cocain and atropin increase it does not seem to be so marked, except of course in marked cases of glaucoma. In normal eyes this effect is practically nil. It has been shown also that paralysis of the sympathetic does not have any effect, at least in one case, on the tension, one side being normal and the other paralyzed. Schiötz also found that absence of the iris and iridectomies did not prevent the diminution of tension, following pilocarpin and eserin, which is a most interesting statement, quite contrary to our usual ideas on the matter.

In my practice I am frequently seeing cases with internists, not only referring the cases to them for further treatment, but receiving them in turn to give advice concerning the sight. In these cases it is of the greatest importance to have a graphic, accurate method of recording tension; and from my cases I have chosen two which are particularly typical of the conditions. By looking in the column where the tension records are kept it will be seen that it steadily decreased under the use of miotics and dionin with appropriate treatment internally, and as the tension decreased the vision increased. The handling of this class of cases is quite another story, and I only speak of these two to show how useful this instrument is and how easily it can be applied.

The notes which are shown on the screen probably need a little explanation. S. V., a man aged 52, has been having failing vision since 1886. His vision blurs and he had a possible diagnosis of cataract made by another physician. The vision is as shown on the chart; he has a large cupping of the nerve-head and several spots of choroidal atrophy. He had gotten glasses of an optician about a year ago and these did not give him any relief. The left eye under the disc and about one and one-half disc-head from it, has a large atrophic spot of choroidal atrophy about one and onehalf times the size of the disc. His wife had consumption, of which she died, but otherwise the family history is good. The tension is very much elevated, as may be seen by reference to the chart. This man was put on mercurials on the possibility that the macular choroiditis was luetic and was also given dionin each day and a physostigmine solution. The vision steadily improved until on April 6th the vision in the right eye was 20-40, when on March 29th it had been 20-130. The blood pressure was also going down. About this time I temporarily abandoned the idea of an operation and the vision steadily improved until it was 20-28, the tension being reduced to 36 and 31 respectively. About this time he began to be careless and the last time I saw him, May 3d, the vision had remained the same but the tension was markedly increased, i. e., 51 and 42.5 respectively. He acknowledged that he had forgotten to put in the miotic, thinking he was cured He was then told to start with the miotic three times daily and to keep the pupils at pin-point. It is extremely difficult in this case to determine the causative factor, but the symptom-complex is that of arterial sclerosis with a possible luetic origin and secondary chronic glaucoma.

The next case, Mrs. J. P., age 52, complains of poor vision, headaches and a feeling as though someone were pushing her eyes out of her head. She has seen haloes and specks for some time. This is a woman whose hair is white and she looks easily seventy (70) years of age. A sister, sixty-one (61) years of age, has lost one eye from chronic glaucoma which later became acute, and has reduced vision in the other eye, on which I did an iridectomy. This early senility is a family characteristic which is an interesting observation on the etiology of these cases. The fundus in this patient shows some cupping of the disc; otherwise normal except for an edematous periphery. She has had her ankles swell and pit and dizziness and shortness of breath. The vision was as shown and the case was looked over carefully and in consultation with the family physician. It was

decided to put her on the infusion of digitalis. This improved her very much; her blood pressure has come steadily down, which you will note is not in accord with the older text books' belief in the use of digitalis, her dizziness has been relieved, her ankles swell slightly but do not pit, and her vision with her correction on is better than normal. This case should be watched closely and measurements taken at least every two months. If we can hold her vision where it is, it is better than an iridectomy. This is a case in which senile changes in the arteries are believed to be the causative factor of the glaucoma.

I have only shown the histories of these two cases, as, with slight variations, they spell the condition of a great many I have seen. I wish, too, to call your attention to the possible relationship between sclerotic changes in the circulatory system and increase of tension without inflammation.

The particular reason which I have in presenting this paper before this section is to ask as many of you as choose to do this work to employ some sort of routine, such as indicated above, in examining your cases for the next year. It is to be hoped that within a year or so we will be able to throw some light on the relationship between diseases of the circulatory system and glaucoma. Even if such a routine should give you nothing more than a correct, graphic record from time to time, your efforts will not have been wasted.

Examinations of urine in these two cases were negative, although I have in a number of cases found at times clouds of hyaline casts, and sometimes the granular form. It is interesting to note that with apparently normal kidney conditions, these interesting variations in pressure occur, not only of the general arterial system but of the intraocular contents as well.

211 Ontario Street.

Mrs. J. P., aet 52. "Headache and feeling as though eyes were being pushed out." See history card, No. 3558 P.

Date-2-9-11. Vision-20-33, 20-28. Tension, Schiötz-Holoc.*-O. D., 22.5 (5.5); O. S., 22.5 (5.5). Medication-Miotic. Dionin.

Date-2-11-11. Blood Pressure, R. R. Wide Cuff-162; 162. Tension, Schiötz-Holoc.-O. D., 25 (5.5); O. S., 22.5 (5.5). Medication-Cascara Sagrada.

Date-2-22-11. Vision-20-22, 20-25. Blood Pressure, R. R. Wide Cuff-148; 142; 144. Tension, Schiötz-Holoc.-O. D., 21 (5.5); O. S., 21 (5.5). Medication-Digitalis by home doctor.

Date-3-1-11. 20-20, 20-28. Pulse-72. Blood Pressure, R. R. Wide Cuff-168;168. Tension, O. D., 25 (5.5); O. S., 22.5 (5.5). MedicationDionin.

Date-3-11-11. Vision-20-28, 20-33. Pulse76; 74. Blood Pressure, R. R. Wide Cuff-158;