Surgical and functional results of augmented superior oblique muscle Z-tenotomy in patients with superior oblique overaction and Brown's syndrome

■ BACKGROUND AND OBJECTIVE: To compare the effectiveness of augmented superior oblique Z-tenotomy (SOZT) with fixed standard SOZT in canceling preoperative superior oblique overaction associated with A pattern anisotropia or V pattern in Brown's syndrome. ■ PATIENTS AND METHODS: Sixteen consecutive patients with superior oblique overaction or Brown's syndrome were treated by removal of a triangular piece of the superior oblique tendon near its insertion (augmented SOZT). Outcome was compared with 20 consecutive historical controls after standard SOZT. ■ RESULTS: The decrease in superior oblique overaction in the right and left eyes and fundus intorsion and the collapse of A pattern anisotropia were more significant for patients with superior oblique overaction (P = .003, P = .007, P = .05, P = .0015, respectively) and patients with Brown's syndrome (P = .025, P = .03, and P = .05, respectively). No study patient with superior oblique overaction and A pattern anisotropia required reoperation compared with 5 of 14 controls (37.5%); rates for patients with Brown's syndrome were 0 for the study group and 3 of 6 (50%) for the control group. ■ CONCLUSIONS: Augmented SOZT is superior to standard SOZT for correcting superior oblique overaction, intorsion, A or V pattern, and stereopsis. It is not associated with complications or reoperation. The size of the Z-tenotomy can be modified according to the intraoperative assessment to achieve symmetric results.