Surgical treatment and muscle protein analysis of V-pattern exotropia in craniosynostosis

The purpose of this study was to compare the differences of V-pattern exotropia in craniosynostosis and normal children. 39 children were included in this study, 19 craniosynostosis and 20 children in control group. They underwent comprehensive ocular examinations and received strabismus surgery. The extraocular muscle samples were analysed. Compared with the control group, craniosynostosis group had larger deviation in primary and up gaze, larger V pattern, and more severe inferior oblique overaction. For 20–40, and 50–60 prism diopter exotropia, the lateral recession in the craniosynostosis group was larger than that in the control group, 7.13 ± 0.44 mm vs 6.71 ± 0.47 mm, 8.90 ± 0.21 mm vs 7.75 ± 0.46 mm (p = 0.025, 0.000). The anterior transposition of craniosynostosis group was more anterior than that of control group, posterior 1.03 ± 1.24 vs 2.68 ± 0.94 mm (p = 0.000). Compared with the control group, the extraocular muscle abnormality in craniosynostosis was significant, 32% vs 5% (p = 0.031). There were 40 proteins in craniosynostosis group, which were different from those in control group. A larger V pattern and larger deviation is common in craniosynostosis children. For the same PD of deviation, it usually needs more recession in craniosynostosis because of the thinner and weaker extraocular muscles. Collagen related proteins were increased in craniosynostosis, and decreased contraction related protein tropomodulin might play key role for the weakness of EOMs.