Measurement of vertical deviations in different gaze positions in patients with a superior oblique palsy

Objective measurements in eight consecutive patients with an isolated congenital superior oblique palsy using a head tilt technique, with gaze directed toward a fixed distance target, and a second technique with gaze directed at a movable near object in different fields of gaze each identified the same oblique position of maximal vertical deviation. We call the latter technique "field-directed." In distinction to the controversy that exists as to which method correctly diagnoses an isolated superior oblique palsy, either technique can be used to direct the surgical correction of this palsy. Superimposing a head tilt on the field-directed technique affected measurements in 16 of the 20 instances where tested. Despite the necessity of avoiding an inadvertent head tilt the field-directed technique is considerably easier to perform and more comfortable for the patient to endure in determining the position of maximal vertical deviation.