An adjustable superior oblique tendon spacer with the use of nonabsorbablesuture

Purpose: Philip Knapp described a method, sometimes referred to as the "chi cken suture," of securing a loose nonabsorbable suture to the cut ends of t he superior oblique tendon to facilitate future reversal. The purpose of th is study is to describe a modification of Knapp's technique to achieve part ial, reversible, and intraoperatively adjustable superior oblique weakening . Methods: The superior oblique tendon was exposed, 2 polyester nonabsorbab le sutures were placed 4 mm apart, and the tendon was cut. With the use of a slip knot, the cut ends of the tendon were separated by 2 to 8 mm. Tendon separation was adjusted intraoperatively according to the exaggerated trac tion test and, in some cases, fund us torsion. Medical records of all patie nts who underwent surgery with this technique were reviewed and the outcome s tabulated. Results: Twelve patients (16 eyes) were treated for superior o blique overaction and 3 patients (3 eyes) for Brown syndrome. Follow-up was 2 to 46 months (mean, 17 months). Mean superior oblique overaction improve d from +1.3 before surgery to +0.3 after surgery, mean A pattern improved f rom 20 PD to 2 PD, and fundus intorsion improved from +1.2 to +0.3. In Brow n syndrome, the mean elevation in adduction improved from -3.8 to -1.0. One patient from each group developed an overcorrection. None of the patients developed recurrence. The patients with Brown syndrome continued to improve over a 1-year period. Conclusions: The superior oblique tendon suture spac er is effective, intraoperatively adjustable, and technically easier to per form than a silicone expander procedure. This technique should be considere d as an alternative for patients requiring superior oblique weakening.