Transactions 29th European Strabismological Association Meeting – de Faber (ed) © 2005 European Strabismological Association, ISBN 04 1537 211 9

A new scoring method for lees charts

M. Eliaçik, S. Akar, B. Yilmaz, B. Gökyig˘it & Ö.F. Yılmaz

Beyoglu Eye Research and Education Hospital, Istanbul, Turkey

ABSTRACT:

Aim: To evaluate lees screening test charts with a new graphic programme.

Method: 33 Patients with paralitic or restrictive diplopia gone into lees screening test had been observed by BEYOGLU EYE RESEARCH AND EDUCATION HOSPITAL STRABISMUS DEPARTMENT between August 2003 and February 2004.

Conclusions: The new method is an useful way to evaluate the lees charts objectively.

Lees charts provide a useful means analyzing and recording muscle imbalance in patients with diplopia. Lees screen test is used to find the orbital muscle or muscles affected by restrictive or paralitic disorders. However, their interpretation is subjective, and comparison between charts may be difficult. In Lees Screen eyes dissociated using two opalescent glass screens at right angles to each other bisected by a two sided plane mirror. (Pediatric Ophthalmology and Strabismus 2000–2001) The points on the chart are shown to patient one by one and told to show the projections of those points on the other side of the chart. The patients answers are checked on a paper by a specialist.(Fig. 1)

In Lees Charts there are 16 outer, 8 inner points and at the middle of the chart there is a central point. Scores for both horizontal and vertical deviations are calculated from the displacement of individual point on the lees chart, using weighting factors fot the center, inner, outer zones. (Sullivan TJ 1992, Fitzsimmons R & White J 1990, Woodruff G 1987) In 1992 G.W. ALYWARD and et al used a new scoring test to calculate the horizontal and vertical scores easily. (Aylward G. W 1992) The programme that they used, did not have an advanced graphical programme so they could not calculate the scores correctly. Their program measured the displacements only in linear mode. Also their program could not compare the tests that were done before at the same time on a screen (Fig. 2)

1MATERIALS AND EXPERIMENTAL METHODS

The scoring system was validated in a group of 33 patients with paralytic or restrictive diplopia who were undergoing surgery, 29 patients had paralitic disordersm 18 (57%) of them had sixth nerve palsy, 6 (19%) of them had third nerve palsy and the others (12%) had fourth nerve palsy,

Figure 1. Lees chart.

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Figure 2. Screenshot of Aylward G.W., McCarry B., Kousoulides L., Lee J.P., Fells P. (1992) “A Scoring Method for Hess charts” Moorfields Eye Hospital, London.

Figure 5. (4. nerve paralysis output).

4 patients had restrictive disorders, 2 (8%) of them had troid ophtalmopaty, one (2%) of them adorbital base fracture and the other (2%) had a diplopia after vitreoretinal surgery. Before and after strabismus surgery these patients had Lees Screen Test and their horizontal and vertical scores were calculated by using a new computer program. Our program software was written by professional pc programmer by using Dat Set 1.1 Microsoft Tech. And graphics were illustrated by

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using visual basic dat.net. (Visul Basic Net 2. Edition) Datas were collected by microsoft access. Datas were transferred between visual dat.net and microsoft access by C sharp software. The displacements of the points on charts were analyzed with fuzzy logic. The displacements of the points were made on program screen by computer mouse and the scores automatically were shown at the left side of the table. Figures 3–4 Also we could compare preoperative and postoperative tests on screen at the same time at the end of the observation we could print results as a special format Fig. 5 and put them patient files.

2CONCLUSION

In 1992 G.W. ALYWARD and et al wanted to calculate the horizontal and vertical scores by using a computer program but that one could not determine distances between the points. Their graphic programme could not show gradients between the points so it only used linear distances between them. In our recent study we used a new graphic programme to remove that problem. So we calculated the scores definitely. We used the same formulas with G.W. ALYWARD and et al. Our scoring system has applications in both research and clinical practice, allowing objective analysis of changes in muscle balance in a variety of motility disorders.

REFERENCES

1.Aylward GW, McCarry B, Kousoulides L, Lee JP, Fells P (1992) “A Scoring Method For Hess Charts” Moorfields Eye Hospital London 6. pp. 659–661

2.Fitzsimmons R & White J. “Functional scoring of the field of binocular single vision” Ophthalmology 1990, 97. pp. 33–35

3.Sullivan TJ, Kraft SP, Burack C, O’Reilly C “A functional scoring method for the field of binocular single vision” Ophthalmology 1992, 99. pp. 575–581

4.Pediatric Ophthalmology and Strabismus 2000–2001 (The Foundation of The American Academy section 6) pp. 64–67

5.Visual Basic Net 2. Edition

6.Woodruff G, O’Reilly C, Kraft SP “Functional scoring of the field of binocular single vision patients with diplopia”. Ophthalmology 1987, 94. pp. 1544–1561

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