title: [Observation of physiological change in the human ciliary body using an ultrasound biomicroscope during accommodation].
abstract: OBJECTIVE
  To evaluate changes in the ciliary body during accommodation using an ultrasound biomicroscope (UBM).
  
  
  METHODS
  Eleven healthy persons, aged from 24 to 33 years, served as subjects. They were asked to lie in the supine position and to fixate a target placed on the ceiling 2 m above with the left eye. A concave lens with the power of -6 to -8 diopters was then placed before the fixating left eye. The thickness of the ciliary body in the right eye was measured by UBM in the nonaccommodative and accommodative states.
  
  
  RESULTS
  The anterior chamber in the right eye became significantly shallow during accommodation. The thickness of the ciliary body significantly increased during accommodation at 0.5 mm and 1.0 mm posterior to the scleral spur. It significantly decreased at 2.0 mm, 2.5 mm and 3.0 mm posterior to the scleral spur.
  
  
  CONCLUSIONS
  During induced accommodation in the left eye, the anterior portion of the ciliary body in the right eye increased and the posterior portion decreased in thickness. The findings imply that the circular ciliary muscles are mainly involved in accommodation and not the longitudinal muscles.
authors.affiliation: Department of Ophthalmology, Osaka Kouseinenkin Hospital, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kano
authors.forename: Y
authors.initials: Y
authors.lastname: Kuwayama
authors.forename: S
authors.initials: S
authors.lastname: Mizoue
authors.forename: T
authors.initials: T
authors.lastname: Hashitani
authors.forename: Y
authors.initials: Y
authors.lastname: Sasamoto
authors.forename: K
authors.initials: K
authors.lastname: Horimoto
authors.forename: H
authors.initials: H
authors.lastname: Okamoto
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000328:Adult; D002924:Ciliary Body / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans