Ocular torsion as a complication of scleral buckle procedures for retinal detachments

Strabismus can occur in as many as 30% of patients after scleral buckle procedures for retinal detachments. Most previous case series have reported on horizontal and vertical deviations. This study examines the frequency of torsion after scleral buckle procedures, the abnormalities of extraocular muscles seen during strabismus surgery, and the surgical procedures effective in improving torsion.

A chart review examined the records of all patients coming to a strabismus referral practice with diplopia reported > or =6 months after scleral buckle procedures.

Forty-six percent of patients with diplopia after scleral buckle operations had torsion (88% extorsion, 12% intorsion). The 2 mechanisms that caused extorsion most frequently were inadvertent production of a superior oblique muscle palsy and tightening of the inferior rectus muscle from the underlying scleral buckle. Other mechanisms of extorsion were also seen. The mechanism for production of intorsion was scarring of the superior oblique muscle to the nasal border of the insertion of the superior rectus muscle. Surgical procedures were successful in reducing torsion 4 degrees or more in 59% of cases.

In patients undergoing surgery for torsion after a scleral buckle procedure, exploration of the superior oblique muscle and the inferior rectus muscle may yield information about the mechanism involved in the production of the torsion.