Effect of wearing multifocal rigid corneal contact lens on binocular visual function in patients with myopia

Abstract

AIM: To investigate the effect of rigid contact lenses with multifocal design on binocular visual function in myopic patients. METHODS: A self-control study before and after. Fifteen myopic students of North Sichuan Medical College were recruited as test persons between July and August 2020. The subjects first wore framed glasses for binocular visual function examination, then wore single vision and multifocal rigid contact lenses(1wk apart), and binocular visual function examination was performed after wearing each lens for 2wk. One-way analysis of variance was used to compare the binocular visual function of multifocal rigid contact lens, single vision rigid contact lens and frame glasses.RESULTS: There were no significant differences among the three lenses in stereopsis, far horizontal phoria, far positive fusional vergence, far negative fusional vergence, near negative fusional vergence, convergence and dispersion flexibility, convergence near point, adjustment magnitude, adjustment flexibility and negative relative adjustment(P>0.05). Compared with frame glasses, multifocal rigid contact lenses had significant difference in near horizontal phoria, near positive fusional vergence, accommodation lag, positive relative accommodation increased and AC/A decreased(P=0.023,0.048,0.001,0.013,0.046); Compared with single vision rigid contact lenses, multifocal rigid contact lenses had significant difference in near horizontal phoria, accommodation lag, positive relative accommodation increased and AC/A decreased(P=0.014,<0.001,0.001,0.009).CONCLUSION:Wearing multifocal rigid contact lenses can lead to near horizontal phoria, accommodation lag, positive relative accommodation increase and AC/A decrease, which may have some influence on proximal use of eyes. These expected changes should be considered in clinical application in order to evaluate and manage patients correctly.

Keywords

• multifocal corneal contact lenses
• binocular vision function
• accommodation response