ABSTRACT
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)
1 MATERIALS 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,
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
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.
