Ocular Torsion Reveals the Mechanisms of Cyclovertical Strabismus The Weisenfeld Lecture

In the mid 1970s, during my ophthalmology training at Johns Hopkins, the mechanisms involved in the common horizontal misalignments of the eyes (horizontal strabismus) were reasonably well understood. At least the muscles involved were known. But even the common forms of cyclovertical strabismus were poorly understood: overacting /underacting oblique muscles, “A ” and “V ” patterns, dissociated vertical deviation, and congenital superior oblique paresis. Over the course of my career, the key to understanding the mechanisms involved in these forms of cyclovertical strabismus has been ocular torsion. This is a chronologic story of how I came to appreciate ocular torsion, learned how to measure it, and with a succession of colleagues have been able to use the torsional positions and torsional movements of the eyes to gain useful insight into the mechanisms involved in these forms of cyclovertical