[Vertical deviation in strabismus in children]

Cyclovertical deviations represent a major diagnostic and therapeutic problem in strabology. In this paper 4 topics are discussed. Long term evolution of strabismus after surgery shows that the patient's residual threshold for a residual vertical factor is very weak; its correction is of the utmost importance. Indeed, if some degree of binocular vision is to be recovered, the residual vertical factor should not be greater than 4 D in esotropia. There are many different varieties of vertical deviation but 3 are particularly common: oblique muscles overactions, DVD and alphabetical syndromes. There are several arguments against sagittalization during oblique muscles development. The author then presents an epidemiological survey of vertical factors based on a randomized study of 1500 consecutive cases of strabismus. In the last section, the problem of vertical factors in accommodative strabismus is discussed; there are many arguments against Gobin and Berard's ideas on the role and management of optical correction in accommodative squint.