True and simulated superior oblique tendon sheath syndromes.

Abstract

Summary The superior oblique tendon sheath syndrome can be divided into two groups—true and simulated. The true cases have positive forced-duction tests and are caused by a congenitally short anterior sheath of the superior oblique tendon. Simulated cases are caused by a congenital structural anomaly of the posterior tendon or by an abnormal firm attachment of the sheath to the posterior tendon, or to both. Acquired and intermittent sheath syndromes are of inflammatory origin and subject to spontaneous recovery. An operation is not indicated in the absence of a disfiguring head tilt or a vertical atropia, but the operative techniques are described for appropriate cases.