title: Fluid dynamics simulation of aqueous humour in a posterior-chamber phakic intraocular lens with a central perforation.
abstract: BACKGROUND
  A modified implantable collamer lens (ICL) with a central hole (diameter, 0.36 mm), a "Hole-ICL", was created to improve aqueous humour circulation. The aim of this study was to investigate the fluid dynamic characteristics of aqueous humour in a Hole-ICL using computational fluid dynamics.
  
  
  METHODS
  Fluid dynamics simulation using an ICL was performed with thermal-hydraulic analysis software FloEFD V5 (Mentor Graphics Corp.). For the simulation, three-dimensional eye models based on a modified Liou-Brennan model eye with conventional ICL (Model ICM, STAAR SURGICAL) and a Hole-ICL were used. Both ICLs were -9.0 diopters (D) and 12.0 mm in length, with an optic of 5.5 mm. The vaulting was 0.50 mm. The quantity of aqueous humour produced by the ciliary body was set at 2.80 μl/min. Flow distribution between the anterior surface of the crystalline lens and the posterior surface of the ICL was also calculated, and trajectory analysis was performed.
  
  
  RESULTS
  The flow velocity 0.25 mm in front of the centre of the crystalline lens was 1.52 × 10(-1) mm/sec for the Hole-ICL and 1.21 × 10(-5) mm/sec for the conventional ICL. Outward flow from the hole in the Hole-ICL was confirmed by trajectory analysis.
  
  
  CONCLUSIONS
  These results suggest that Hole-ICLs improve the circulation of aqueous humour to the anterior surface of the crystalline lens.
authors: Department of Orthoptics and Visual Science, Kitasato University School of Allied Health Sciences, 1-15-1 Kitasato, Minami-ku, Sagamihara City, Kanagawa, Japan 252-0373, kawa2008@kitasato-u.ac.jp
authors: Takushi
authors: T
authors: Kawamorita
authors: Hiroshi
authors: H
authors: Uozato
authors: Kimiya
authors: K
authors: Shimizu
mesh_terms: D001082:Aqueous Humor / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D057446:Hydrodynamics; D019654:Lens Implantation, Intraocular; D007908:Lens, Crystalline / Q000502:physiology; D008954:Models, Biological; D054120:Phakic Intraocular Lenses; D011474:Prosthesis Design