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Usefulness of the preoperative prism adaptation test in patients with intermittent exotropia
Subhash Dadeya1, Kamlesh, Sanjive Naniwal
1Squint and Orthoptic Section, Guru Nanak Eye Centre, Maulana Azad Medical College, Delhi, India.
Purpose:
To investigate whether the preoperative prism adaptation test is useful in patients with intermittent exotropia.
Methods:
Sixty-five consecutive patients with basic-type intermittent exotropia <40 prism diopters (PD) comprised the study population in this prospective study. Patients were divided into two groups based on the results of the prism adaptation test. Patients with a negative response comprised group 1 and patients with a positive response comprised group 2. Group 1 patients (n=26) underwent surgery according to the original angle, and group 2 patients (n=27) underwent surgery in accordance with the change in the angle of deviation with prisms.
Results:
Satisfactory motor alignment (+/- 5 PD of orthophoria) was achieved in 14 (53.8%) group 1 patients and 24 (88.8%) group 2 patients (P=.01). Mean residual deviation was 9.8 PD in group 1 and 4.5 PD in group 2 (P < or = .05).
Conclusion:
The prism adaptation test may be helpful in achieving a favorable surgical outcome in intermittent exotropia.
