[Symptomatologic value of dissociated vertical divergence in concomitant strabismus]

D.V.D. is an opto-motor anomaly which is likely starting from the retina. D.V.D. is seldom isolated and it is most often found in congenital strabismus or in early onset strabismus (with or without alterared fusion) with an horizontal deviation most often associated with a vertical syndrome. The clinical assessment of D.V.D. is of major importance in the pre and post-operative examination. The simultaneous horizontal and vertical surgery reduces the amplitude of D.V.D by re-establishing a central or peripherical fusion.