Clinical observation on binocular vision in patients with vertical muscle paralysis

Abstract

A retrospective clinical study was conducted to observe the changes of the binocular vision in patients with vertical muscle paralysis . All patients were examined by using synotophore and stereoscopic vision chart. The results were analyzed by SPSS( statistical product and service solutions) and the variations of synotophore and stereoacuity were mainly observed. Our study revealed that out of 50 patients, 45 (90%) maintained the stereocauity, and all the 50 had fusion function, but with horizontal fusion range smaller than the normal, and their vertical fusion ranges were greater than the normal, showing there was statistically significant difference ( P 0. 05). Among those with vertical deviation ≤10△, as comparing with those > 10△ ( chi-square test P 0. 05). It suggested that all cases with vertical muscle paralysis might maintain the fusion function, while 90% cases keep the stereoscopic vision. The angle of vertical deviation might affect the near stereopsis, showing that increasing vertical fusion range shouled be a compensation for maintaining the binocular vision caused by vertical deviation. Key words: Strabismus; Depth perception