The Clinical Characteristics of Dissociated Vertical Deviation Combined with Exotropia

ABSTRACT

PURPOSE: The clinical characteristics and post-operative prognosis of dissociated vertical deviation (DVD) combined with exotropia was evaluated. METHOD & MATERIALS The clinical appearance such as the frequency of DVD, vision, amount of deviation, stereoacuity, sensory abnormality, the presence of latent nystagmus, head tilting and operation results were evaluated in patients who were diagnosed with comitant exotropia followed by surgical correction with 3 month follow-up. RESULTS: Eight (16.0%) patients had exotropia combined with DVD, the combined DVD showed an angle of vertical deviation 15.88+/-7.26 delta, for the right eye and 13.50+/-6.55 deltafor the left eye in the primary position. All but 1 patient showed subnormal stereoacuity in the Titmus stereopsis test and most showed suppression in near and far in the Worth 4 dot test. Four (50%) patients were associated with latent nystagmus and one (12.5%) patient showed head tilting. Three months after the operation, all patients showed a residual DVD under 8 delta. CONCLUSION: DVD is frequently combined with exotropia and is associated with decreased stereoacuity, latent nystagmus, head tilting, inferior oblique overaction (IOOA), and superior oblique overaction (SOOA). DVD showed no relation to the amount of deviation of exotropia but was usually associated with a small angle of exotropia ( or =50 delta). The correction of DVD with exotropia showed satisfactory results.