Surgical Innervational Effect In The Treatment Of Lateral Rectus Paresis: A Prospective Study

1. Dr. Savleen Kaur¹
2. Dr. Kamlesh¹
3. Dr. Anju Rastogi¹
4. Dr. Prem Vardhan¹
5. Dr. Shilpa Goel¹
6. Dr. Ashray Nayaka¹

¹Guru Nanak eye centre, New Delhi, India

Purpose: To compare the outcome of bilateral medial rectus recession (BMRr) for chronic lateral rectus paresis (LR paresis) based on Sherrington's law and the innervational effect by Horta Borbosa, (i.e. weakening of a muscle of the sound eye in order to increase the innervations to its paretic yoke muscle) with ipsilateral recession resection.

Method: 10 patients of chronic LR paresis were treated by ipsilateral recession resection (group A) and 10 with BMRr (group B) with a minimum follow up period of 6 months.

Result: In group A the mean deviation for distance was 40.10 and for group B was 41.70 pre operatively. Post operatively eight (80%) cases in Group A and nine (90%) cases in Group B achieved acceptable alignment (± 10 PD) in primary position, difference was not significant statistically. Compared to group A after surgery, all 10 patients in group B had better improvement in abduction with an expansion of their field of binocular single vision (BSV) consistent with the degree to which the eye was surgically straightened. (Field of BSV vision increased from a mean value of 70 % to 77.7 % in group A and from 68.8% to 79.2% in group B (p = 0.01)).Both the groups showed an elimination of diplopia in primary position with significant reduction in head turn.

Conclusion: BMRr is equally safe and effective option for chronic unilateral LR paresis and gives a better improvement in abduction hence a wider field of BSV as compared to ipsilateral recession resection surgery.