Vertical transposition of the horizontal rectus muscles to correct head tilt because of infantile nystagmus syndrome – A case series

Purpose: Head tilt associated with infantile nystagmus syndrome (INS) can be corrected by (a) operating the oblique muscles, (b) horizontally transposing the vertical rectus muscles, or (c) vertically transposing the horizontal rectus muscles. We report three cases of INS with head tilt corrected by vertically transposing the horizontal rectus muscles in both the eyes. Methods: Three cases of head tilt with INS from an institutional practice operated by a single surgeon were retrospectively reviewed and analyzed. The intervention included full tendon width transposition (upward or downward) of all four horizontal rectus muscles to induce cyclotorsion in the direction of head tilt. The primary outcome measure was the correction of head tilt in the primary position. Results: Three patients (boys) of ages ranging from 4 to 7 years with a pre-operative head tilt of 30° were operated upon. Although one patient’s oblique muscles had been operated on to correct head tilt, another patient had an unmasked face turn after the surgery, which was corrected with a modified Anderson’s procedure. Post-operatively, all patients had a reduction of head tilt to a range of 0–10°. Conclusion: Vertical transposition of horizontal rectus muscles is a simple surgical option to correct head tilt in INS. However, the results may vary based on individual cases.