Degree of Deviation Causing Amblyopia in Squint Patients
Background: Cases of EXO and ESO deviation in various age groups and different sexes having central and eccentric fixation were taken. Materials & Methods: Out of 53 cases, 28 were of ESO. Of all the strabismic cases maximum number of cases reported in age group of 11-20 with male preponderance. if the angle required for superimposition was zero a patient with orthophoria had NRC and with heterophora had harmonious ARC. Measurement of objective angle of deviation was done by Hirschbergs method of corneal reflex and subjective angle of deviation with Maddox Rod test with Maddox hand prisms. The angle of anomaly was calculated with Objective Angle- Subjective Angle.
Results: Maximum number of cases in up to 15 degrees were of unilateral esotropia and in 16 to 20 degrees also the cases of unilateral esotropia were maximum. However, in above 30 degree the maximum number of cases were of unilateral exotropia.
Conclusion: Amblyopia once has set in then it is very difficult to correct it even if the angle of deviation is up to 15 degree.
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