Study of the Orthoptic Assessment in Refractive Eye Surgery

Purpose: The aim of our study was to assess the variations in fusion and stereopsis before and after refractive surgery. Methods: We conducted a retrospective study. 140 patients (78 M, 62 F) were selected, aged 20 - 59 years (mean age 36 ± 10 DS). All patients received a comprehensive ophtalmological and orthoptic examination. Surgery was performed using a MEL-80 excimer laser (Carl Zeiss Meditec, Jena, Germany). Results: Fusional convergence amplitudes after refractive eye surgery range from at near 18 - 20 PD in 42 (30%) patients; 25 - 30 PD in 56 (40%) patients; 35 - 40 PD in 42 (30%) patients, at far 20 - 25 PD in 84 (60%) patients; 30 - 40 PD in 56 (40%) patients, fusional divergence at near after refractive eye surgery range from at near 6 - 8 PD in 108 (75.7%) patients; 10 - 12 PD in 52 (37.1%), at far 6 - 8 PD in 126 (90%) patients; 10 - 12 PD in 14 (10%) patients. None of the patients developed any ocular deviations. NCP, on average, decreases from 9.4 ± 1.5 cm to 9.1 ± 0.9 cm after. None of these patients with a normal NCP before surgery developed an abnormal NCP after refractive surgery. Eighteen patients (12.8%) had a stereopsis higher than 60 s of arch before surgical intervention. Of these, in 2 cases (2.8%) stereopsis increased from 200 to 40 s of arch after surgery. In the rest of patients stereopsis remained unchanged. Conclusion: The increase in fusion at near appears to be considerably interesting, whereas there is no worsening of stereopsis. A careful pre-surgery orthoptic evaluation is extremely revelant for a safe refractive surgery, this reducing the risk of complications associated with fusion and stereopsis.