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?

Revelle A Littlewood,John P Burke

doi:10.22599/bioj.171

Abstract

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.

Highlights

Congenital or early onset torticollis can result from both orthopaedic and ophthalmic related pathologies, and when prominent, can be disabling for a young child and distressing for parents
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? British and Irish Orthoptic Journal, 17(1), pp. 33–40
There exists experimental concern relating to the neurotoxicity risk of general anaesthesia in young children, and the risks are not fully understood (Clausen, Hansen & Disma 2019; Rappaport et al 2015), it appears prudent where practical to minimise the frequency of elective procedures in this age-group

Summary

Introduction

Congenital or early onset torticollis can result from both orthopaedic and ophthalmic related pathologies, and when prominent, can be disabling for a young child and distressing for parents. Unilateral, superior oblique muscle underaction (SOUA)/inferior oblique overaction (IOOA) is the commonest cause of vertical strabismus associated with a compensatory head-tilt (CHP) or torticollis, where the child assumes excessive lateral or side-flexion of the cervical spine towards the shoulder, the normal range being up to 45 degrees (Corrigan & Maitland 1983) with/without other malposition’s including face-turn and/or chin elevation/depression. Overtime, untreated CHPs’ lead to musculoskeletal sequelae that includes scoliosis and tight sternocleidomastoid (SCM) muscles, where SCM tightness can explain or contribute to residual torticollis following successful strabismus surgery (Lau et al 2009). Many more present as older children and adults with diplopia where torticollis is not the presenting symptom This frequently studied older group have more successful surgical outcomes than those presenting as infants/toddlers with severe torticollis. Neither study described superior oblique traction test (SOTT) findings or involved surgery on the superior oblique muscle

Results

Discussion

Conclusion