Study links refractive error to ciliary muscle thickness in children
Posterior ciliary muscle fibers were thicker in children with myopia, while the apical region of the ciliary muscle was thicker in hyperopes, according to a study.
“This is likely the first evidence suggesting that accommodative workload is associated with a specific region of the muscle, which is largely comprised of circular and some radial fibers,” the study authors said.
The prospective study included 269 children with a mean age of 8.71 years.
Investigators used anterior segment optical coherence tomography to measure cycloplegic ciliary muscle thicknesses at 1 mm (CMT1), 2 mm (CMT2) and 3 mm (CMT3) posterior to the scleral spur and to assess maximum ciliary muscle thickness. They used autorefraction to assess spherical equivalent refractive error.
Study results showed significant linear relationships only between refractive error and CMT2 (P = .0008) and CMT3 (P = .007).
There was a statistically significant linear relationship between refractive error and apical fibers at CMT1 and maximum CMT (both P < .0001).
CMT values increased with age in all muscle regions, the authors said.
Disclosure: See the study for a full list of all authors’ relevant financial disclosures.