How Successful is Combined Superior and Inferior Oblique Muscle Surgery in Young Children with Superior Oblique Underaction Presenting in Infancy with a Severe Head Tilt?

BACKGROUND/OBJECTIVE: To evaluate the success of combining ipsilateral inferior and superior oblique muscle surgery in young children with congenital unilateral superior oblique under action who present in infancy with a large socially noticeable head-tilt. METHODS: A consecutive retrospective case series of young children was analysed. The success of surgery in eliminating the head-tilt was evaluated by pre- and post-operative ocular motility assessment focusing on the vertical misalignment in primary position and downgaze, the magnitude of the head-tilt in degrees and the status of the superior oblique tendon. RESULTS: Five children had a mean age at first surgery of 41 (range 25–63) months, a mean primary position vertical deviation of 26 (25–30) prism dioptres, a head-tilt of 30 (20–35) degrees and a mean post-operative follow up of 24 (8–43) months. While there was a uniform surgical plan, nonetheless each operation required individualisation based on a spectrum of per-operative superior oblique tendon findings. The head tilt was eliminated in 40% and reduced in the remainder, to a mean of 7 (0–18) degrees and with a mean post-operative primary position vertical misalignment of 3 (range 0–10) and of 10 (range 0–40) prism dioptres in downgaze. CONCLUSION: Combined, ipsilateral oblique muscle surgery reduced the severe head tilt and primary position alignment to a psychosocially and functionally acceptable level. For the majority, the outcome was stable or associated with further decremental improvement. A persistent downgaze vertical tropia occurred in children with macroscopically abnormal superior oblique tendons but these cases were not identifiable clinically pre-operatively.