The Quantitative Measurement of Oblique Muscle Action by Digital Videographic Method

Jeong, Chang Woog; Han, Sueng Han; Lee, Jong Bok

Abstract

PURPOSE: The overaction or underaction of oblique muscle is generally evaluated by grossly observingmaximal ductional eye movements, therefore, leading to various results among practioners. This study is to attain objective and accurate muscle function tests by digital videographic method and to verify its accuracy.
METHODS
15 patients with inferior oblique overaction and 7 patients with superior oblique underaction were involved. The subjects were examed by both the gross and digital method and the results were compared.
RESULTS
The average difference between gross and videographic analysis was ranging from 0.01 to 1.18. A difference of less than 0.5 was found in 12 patients and 2 patients showed a difference of greater than 1.0. The linear regression curve between digital and gross analysis methods was y=0.93 x -0.10(x=gross method, y=videographic method). The coefficiency of variation to verify its reproducibility for measurements of total variability in 22 patients was 19.66% in gross method and 6.93% in videographic method.
CONCLUSIONS
There didn't appear to be significant difference between the results by gross and digital method of analysis but, appeared to be significant difference between the coefficiency of variation by gross and digital method of analysis. Digital videographic measurement, therefore, may be an objective method of examining supraduction and infraduction in oblique muscle which requires further effort in its standardization and precision.