Clinical study on camera-assisted measurement for measuring squint angle of concomitant strabismus / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate camera-assisted measurement in evaluating the accuracy of Hirschberg Test in measuring squint angle of concomitant strabismus.<p>METHODS:The clinical data of 105 patients with concomitant strabismus who were admitted to the hospital during the period from January 2016 to January 2018 were collected. After admission, they were given traditional Hirschberg Test and picture Hirschberg Test for squint angle examination.Taking the prism cover test as golden standard, the deviation values between squint angle measured by golden standard and those measured by the traditional Hirschberg Test and the picture Hirschberg Test were recorded.The influence of Kappa angle on the deviation value was analyzed.The application value of camera-assisted measurement in squint angle of concomitant strabismus was analyzed.<p>RESULTS:There was a significant difference in the value of squint angle measured by traditional Hirschberg Test, picture Hirschberg Test and prism cover test test(<i>P</i><0.05), and the squint angle measured byprism cover test test was higher than that of picture Hirschberg Test method(<i>P</i><0.05), and the angle in picture Hirschberg Test method was higher than that in traditional Hirschberg Test method(<i>P</i><0.05), and the consistency of picture Hirschberg Test method and prism cover test test in measuring squint angle was higher than that of Traditional Hirschberg Test method(<i>P</i><0.05).There were significant differences in the deviation values of squint angle measured by traditional Hirschberg Test among the 4 examiners(<i>P</i><0.05).The deviation values of all examiners measured by traditional Hirschberg Test were higher than those by picture Hirschberg Test(<i>P</i><0.05).The deviation degree of picture Hirschberg Test was lower than that of traditional Hirschberg Test in terms of the examination of squint angle in patients with positive and negative Kappa angle(<i>P</i><0.05).<p>CONCLUSION: The deviation of camera-assisted measurement picture Hirschberg Test is lower than that of traditional Hirschberg Test for the measurement of squint angle of concomitant strabismus, and it is more suitable for young patients who cannot cooperate with.

Measurement of Angle Deviation Using Digital Photographs

PURPOSE: The prism-cover test has been known to be the most accurate method in measuring ocular angle deviation, but the Hirschberg test is used in poorly cooperative patients. To enhance the accuracy of Hirschberg test, we designed a geometric model using digital photographs. METHODS: Fifty normal volunteers were included in this study, who had no ocular disorders. Digital photographs were obtained in the subjects seated 2 m in front of the fixation targets and the camera was set 1 m in front of subjects. In each photograph, the apparent width of the cornea and the distance from the corneal light reflex to the limbus were measured using computer program for calculation of angle deviation. Then we compared the calculated angle deviation with the actual one. RESULTS: Calculated angle deviations with digital image photographs were corresponded to the actual ones from esodeviation 40delta to 10delta (p>0.05), whereas in esodeviation 60delta, 70delta and exodeviation, the larger the deviation angle, the larger the calculated angle composed with the actual one. CONCLUSIONS: Angle deviation measurement using digital photographs appears to be relatively precise and its clinical application will be available in measuring angle deviation of esodeviation.

Comparison of Hirschberg Test with Prsim and Alternate Cover Test in Measuring the Ocular Deviation

Measurements of ocular deviation were obtained from 45 exotropes and 31 esotropes, using Hirschberg corneal reflex test, and prism and alternate cover test respectively. The mean angle of devation in exotropes was 27.42 +/- 8.60 delta by Hirschberg test, 27.80 +/- 8.11 delta by prism and alternate cover test. There was no significant difference between these two groups (p>0.05). The mean angle of deviation in esotropes was 28.55 +/- 12.92 delta by Hirschberg test, 31.58 +/- 13.08 delta by prism and alternate cover test. The difference between these two groups was significant (p<0.05). In patients whose angle kappa was zero and exotropes whose angle kappa was positive, there was no significant diHerence between the two tests. In esotropes whose angle kappa was positive, the mean angle of deviation was 29.74 +/- 15.59 delta by Hirschberg test, and 33.47 +/- 15.91 delta by prism and alternate cover test. The difference between the two groups was significant (p