Abstract
Purpose :
Unicoronal craniosynostosis (UCS) patients often show a head tilt, of which the origin is still uncertain in many UCS patients. The tilt may arise from sternocleidomastoid muscle contraction or is ocular caused. This study aims to establish the prevalence of an ocular head tilt (OHT) in non-syndromic UCS patients and explore possible associated ocular features. Also, MRI was employed to investigate changes in the extraocular muscles in these individuals.
Methods :
This cross-sectional study retrospectively reviewed medical records from 1994 to 2022 for non-syndromic UCS patients treated at a university hospital in the Netherlands. Patients were included if their data mentioned: visual acuity, binocular single vision (BSV), type of strabismus, ocular motility, alphabetical patterns, refractive error, amblyopia, presence and direction of a head tilt. Patients were categorized as having an OHT based on their ophthalmic and orthoptic diagnosis. MRI brain data were obtained with a 1.5T Unit (General Electronic Healthcare, Chicago, IL, USA), including T1 and T2 sequences.
Results :
Data of 146 patients was included (mean age at initial examination was 3.5 years (SD 4.4)) of whom 57 showed a head tilt, with an ocular cause identified in 54 cases. Age of initial head tilt identification was 2.9 years (SD 2.7). The prevalence of OHT was 37% (n=146; 95% CI [0.292-0.454]). The primary cause of the head tilt was incomitant strabismus (n=47; 87%) followed by concomitant strabismus (n=6; 11%) and congenital nystagmus (n=1, 2%). Pseudo-superior oblique palsy was the most common subtype (n=34; 59.6%). Significant associations were found between OHT and ocular motility abnormalities (p<0.001), alphabetical patterns (p<0.001), strabismus (p<0.001) and amblyopia (p=0.002). In a subset of 24 patients with pre-craniofacial surgery MRI scans, all extraocular and oblique muscles were present. The ipsilateral side of the closed suture exhibited a smaller and asymmetric superior oblique muscle.
Conclusions :
One in three UCS patients has an AHT. The head tilt in UCS patients is predominantly ocular related. Important to note was that the head tilt manifested at different ages. MRI analysis revealed a reduced volume of the superior oblique muscle on the side of the closed suture. These findings highlight the importance of including ophthalmic and orthoptic assessments in the treatment strategy for non-syndromic UCS patients.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.