F R O M THE 2nd U N I V . EYE HOSPITAL, BUDAPEST

RESULTS WITH CONTACT LENSES; A COMPARATIVE STAT1 STICS.

By 1. Gyorffy.‘)

The best way to demonstrate the results and other con- tributions with contact lenses seems to be the statistical syn- thesis. The usefulness of this statistics can be increased by the application of other authors results on the same tables in a comparative manner.

The first publication concerning results of wearing contact lenses in a large number of cases is Sattler’s analysis (1938) describing in detail 120 cases, where patients wore mostly Zeiss lenses. Williamson-Noble’s results are equally from 1938, he describes 40 replies received on the 81 questionnaires.

In 1944 I have given an account of my results with indi- vidually moulded acrylic lenses by analysing 100 cases; I summed them up in detailed tables. Mann describes equally 100 patients in 1947. Ridley (1946,1948) and Williams (1948) publish iess detailed their results on the field of contact lenses.

Cross elaborates in tables 8 i 5 cases (1949). His statistics are the most resourceful by analysing the largest number of cases in the literature and examining the subject in every possible aspect. The statistics of Abraham & Shanedling (1950) are precious too, they compiled their tables describing 107 received replies.

The results of Graham have to he mentioned, but his publication (1949) about 407 corneal lens cases can not be analysed within the present article because of the differing character and the limited use of this lenses at present. On -__-

*) Received October 30th. 1951.

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the other hand I refer to the statistics of Berens - though who doesn’t discuss contact lenses as such - but tried to establish the number of those ophthalmic surgeons in the U. S. A. who work with these lenses. He was able to lay down of the 5 i 5 replies he received, that 3i3 of them used moulded lenses, 22 tangent cone-, 18 trial lenses, and 162 surgeons did not order lenses a t all. A braham’s investigation had the same purpose, among his 300 replies 62 surgeons ordered all to- gether 1407 pairs of lenses: 38 moulded-, 2 trial type, and 19 ophthalmologists did not communicate the type of lenses their prescribed.

Sly present analysis concerns 450 patients, i. e. 824 lenses ordered for them. The particulars for the inyestigation were risen during the past year from questionnaires, correspondence and personal connections. The investigation was closed in Au- gust 1951 after the necessary material of the 450 cases was gathered.

M y fitting method is as follows: The patients arc supplied with individually fitted acrylic lenses, with a dioptric power. The form of the eye is determined by a haptic shell, which is selected from a haptic trial set containing 150 pairs of contact lenses from different form and different size. The type of the ordered lenses is a transition between the glove-fit and the tangent-cone, i. e. they are approximately exactly fitted to the eyeball, but the pressure of the haptic part is not even, it is maximally 2-3 mm. from the limbus and diminishes equally towards the limbus and the edges. Corneal apex confacf is let only if the tolerance allows it, in conical cornea possibly al- ways. If i t does not disturbe the vision I prefer to leave a larger limbal clearance with a bubble. In such cases the cen- tral corneal contact makes the use of a fluid superflous and the veiling is completely omitted. Sometimes I even perforate the shells a t the limbus, but I experienced rarely further im- provement in the tolerance. The number of sessions employed in fitting was 3-8, the fitting process takes place once or n h e n urged twice a day.

The diameter of the lenses are proportional to the size of. the eyeball. The scleral rim alternates between 5-8 mm.,

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temporal between 8-13 mni. The lens has the same ino\-e- ment as the eye, it does not slip out of its place even by looking on the side. To prevent the deposit of sebum on the outer sur- face of the lens the wetting of the lens with the own saliva before inserting is found to be a very successful method.

M y results in statistics are the following:

1. N u m b e r of cases:

450 patients ' fitted on both eye: 84 %

fitted on one eye : 1 7 % I- (824 lenses) I

2. Sex:

Males 53.6 46.7 46.0 63.0 36.5 24.0 Females 46.4 53.3 54.0 37.0 63.5 76.0

3. The uge of pa t i en t s w h e n contac t lenses were ordered:

19)- 15 1.; 16 - 20 14.7

1 .o } 8.0 16.0

21 - 30 39.0 37.0 65.0 50.0 31 - 40 33 --.. 3 ma Jority 19.0 20.0 ?0.0

'" } 14.0 41 - 50 16.2 15.0 51 - 60 4.0 12.0 61 -((80'1 2.2 4.0

4. D o m i c i k : Budapeht 6 2 rc CountrJ- 31 5% Foreign countries 7 %

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5. Occupat ion:

Sattler I Hlum Ahraliani

Official Housewife Student Fabric workman Sport champion Salesman Tradesman Artist Musician Teacher, writer Farmer, farmlabourer Soldier, patrolman, seaman Doctor, pharmacist Engineer Driver, mechanic Different

18.7 13.0 11.5 11.0 8.7

5.6 s** } 4.7 1.6 3.6 5.5 2.0 2.0 1.1 1.3 1.3

32.0 29.0 20.0

20.0 20.0 30.0

20.0

] 6.5

10.0

50.0 12.5 50.0

F. T h e percen tage of persons who w e a r the ir lenses espec ia l ly f o r spor t .

(50 patients: 11 %-lo0 %).

% % football 34 boxing 4

handball 8 wrestling 2

icehockey 6 skiing 2

waterpolo 20 table tennis 2 swimming 10 lawn-hockey 2

gasketball 6 motor racing 2

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7. O c u l a ~ conditions f o r w h i c h contact lenses were ordered:

~-

Fitted cases 450 120 40 100 200 875 38 ~ . - __ - - _- ~

0,o I 010 0 010 010 010 010

Myopia low myopia 1-3 D. middle )) 3-10 D. high )) 10- D.

Keratoconus Irregular astigmatism Hypermetropia

low hm. 1- 3 D. middle )) 3-10 D. high x 10- D.

Aphakia High regular as-

tigmatism High myopia + Cen-

tral choroid. atrophy Ast. after corneal

transplantation Mustard gas keratitis

60.2 66.0 12.0 25.3 22.7 18.9 10.0 9.8 4.0 5.0 2.0 1.5 0.4 3.6 13.0

1.3

1 .8

2 cases -

4’7.5 61.0 93.0? 59.0 48.0

P O 2 11.0 10.0 21.0 7.8 0.5 1 case 7.0 3.0

10.0 4.0 1 case

0.5

17.5 1 case

14.0

8. T h e ? , i i v i B e r . of years , si t ice the leiises were f i t ted:

8.0 22.0 17.0

13.6 10.0 12.9 8.0

20.0 1.0

~ .. ~ -~ -~ ~

- 1 1 - 2 2 - 3 3 - 4 4 - 5

5 - 10 17.3 10 - 13 12.7 30 Oio

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9. Previous exainiiiation of the suitabili ty for coritact Eetises, aspect the ocula?. and netuot ic conditions.

I suitable 1 unsuitable

1949 52 % 48 % 1950 58 % 42 %

37 % 1951 63 %

RidIey 1948 80 % '70 % -~ - -____ . . ~- -

10. The results of zoearings:

I oio I Mann /Cross/ Abraham

55 55 31 9 12 38

Every day Occasionally No 13 23 33 31

I

gt } 8i'

11. The auerage period f o r which contact lenses are worn ( * 8 7 % = 100%)

hours I Ol0 1 Cross Abraham

'2 - 3 18 16 26 4 - 5 23 '75 40 6 - 8 26 8 5-: 23 8 - 23 30

18 variable - - -

12. Total n u m b e r of hours, the lenses are w o r n dicriug a day ( * 8 7 % = 100%)

hours I oiO I Mann ' Ridley Cross i Bluni 1

- - - - '70 - 2 - 2 - 4 14 - 32 5

4 - 6 16 - '70 10 16 47 86 18

6 - 8 24 8 - variable -

- -

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13. Are y o u satisfied with y o u r lenses? Would y o u go in f o r contact lenses again? (From those who wore their lenses regularly and occasionally).

I 0,io 1 Mann 1 Ridley ~ Cross /Abraham

Yes 68 64 70 88 51 NO 8 19 30 3 37 Uncertain 24 17 - 9 12

14. The type of lenses which are made:

Individual fitted (moulded) ........................ 93.0 % Zeiss type ........................................... 3.1 % Fenestrated .......................................... 2.7 % Lenses with toric dioptry (at lenticular astigmatism) 1.2 %

Discussion.

Table 1. In 20 % of the cases I fitted for one eye only, mostly because the other eye was uncorrectable, exceptionally because the other was perfect (monocular aphakia! .

Table 2. In contrary to the precedent statistics - except the one of Ridley - in my practice m e n were in majority.

Table 3. Concerning the age of the patients the youngest was a girl of 9 years, the oldest a woman of 80 years. The peak period were between 21-30 years.

Table 5. As for the >)occupation<< grouping the literature gives us few details. The percentage of students is, however, high in every statistics.

Table 6. Among sportsmen the football players and water- sportsmen are represented with the highest number.

Table 7. In the diagnosis group the myopics are in majo- rity. The proportion of conical cornea cases are between 10- 'LO %. The monocular aplzakia is not separately discussed, I fitted five cases aiming the improvement of the binocular vi- sion, in 4 cases with much success. In high myopia connected with central choroidal atrophy I could exploit the ocular image enlarging effect of the lens, and so I could reach a sight improvement of 20-30 % compared to ordinary spectacles. Mustard gas keratitis cases I had none.

Acta Ophthalmol., Val. 30, 111. 22

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Table 8. *I3 of the lenses were fitted during the last 5 years, ‘13 mere fitted previously.

As demonstrated in table 10, among the patients are re- latively few who had given up wearing their lenses. To com- ment upon this fact I have to say, that before fitting the patients are examined as regards their aptitude to tolerate lenses (table 9.), and the fitting starts only when the com- ponents of the possible sight improvement, the eye’s anatomi- cal construction, the physical and neurotic factors seems to predict favourable circumstances for the wearing. Further, the majority of the lenses are ordered on medical prescription, aiming the improvement of the eyesight or have professional causes. The cosmetic purpose is relatively rare. The ,occasion- ally<< group is larger then normally, because the sportsmen artists, and generally the >>professionally<< wearers change often the lens after work to spectacles.

As shown in tables 11 and 12, 50 7% of the patients wear their lenses uninterrupted during a period of 4-8 hours, 25 % longer than 8 hours. The daily tolerance is more than 8 hours in 46 %. These results are generally in accordance with the statistics of other authors, excepted the one of Blum, where the daily wearing period is much longer, i. e. the double of the arerage.

Summary.

There are published results with contact lenses based on the investigation of 450 patients. A review is given about the fitting method, and the particulars of the fitted lenses, further follows a detailed statistics composed in tables. For com- parative purposes the tables contain the parallel data of other statistics published in the literature. The results can be easily established out of the figures.

REFERENCES

-4bmltam & Shanedling (1950): Amer. J. Ophthal. 33: 933. Berens, C. (1949): Journ. Amer. Med. Assoc. 140: 602. Blum, J . D. (1949) : Ophthalmologica 11’7: 214.

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Cross, A. G. (1949): Brit. Journ. Opht. 33: 421. Graham, R . (1949): Amer. J. Optometry 26: 75. G y o r f f y , I . (1944) : Ophthalmologica 108: 44. Mann, I. (1947): Brit. Journ. Opht. 31: 565. Ridley, F. (1946): Proc. Roy. SOC. Med. 39: 842.

(1948): Modern trends in ophthal. 11. 427. Sattler, C. H . (1938): Klin. Monbl. 1938: 172. Will iams, D. (1948): Med. Journ. Australia 2: 419. 7YilZiamson-NobEe 11938): Trans. Opht. SOC. U. K. 58: 11: 535.

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