title: Determination of the solubility of perfluorocarbon liquids in silicone oil in vitro and in vivo.
abstract: OBJECTIVE
  To investigate the solubility of perfluorocarbon liquids (PFCL) in silicone oil.
  
  
  METHODS
  Forty-eight samples of silicone oil (1,300 mPas, n = 22; 5,000 mPas, n = 26) were analyzed for dissolved fluorocarbon molecules after surgical removal from patients who had initially undergone vitreoretinal surgery with (n = 41) and as control without (n = 7) the use of perfluorodecalin in headspace gas chromatography. In vitro, the solubility of three different PFCL-perfluorooctane (PFO), perfluorodecalin (PFD), and fluoromethylcyclohexane (FMCH)-in silicone oil of various viscosities was determined. The diffusion phenomena during a direct exchange were studied.
  
  
  RESULTS
  In 39 of 41 silicone oil samples removed from patients who had undergone vitreoretinal surgery with the use of PFD, small amounts of dissolved perfluorocarbons could be detected. The mean value in 5,000-mPas silicone oil was 939.0 x 10-4 m/% and in 1,300-mPas silicone oil was 322.75 x10(-4) m/%. No perfluorocarbon molecules were found in seven control patients. In vitro, the following maximum solubilities in 1,000-mPas silicone oil were measured at room temperature: PFO, 3.2 m/%; PFD, 5.1 m/%; and FMCH, 10.3 m/%. The maximum values measured in 5,000-mPas silicone oil were PFO, 3.3 m/%; PFD, 5.7 m/%; and FMCH, 8.5 m/%; and in 100-mPas silicone oil were PFO, 2.4 m/%, and PFD, 5.1 m/%.
  
  
  CONCLUSIONS
  Perfluorocarbon liquids dissolve in silicone oil. This may lead to transient formation of "heavy silicone oil," but no stable heavy silicone oil can be created adding PFCL. Intraocularly, retained PFCL vanish in silicone oil and are removed during silicone oil removal.
authors.affiliation: Department of Ophthalmology, University of Lübeck, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Hoerauf
authors.forename: Frank
authors.initials: F
authors.lastname: Faude
authors.forename: Dirk-Henning
authors.initials: DH
authors.lastname: Menz
authors.forename: Joachim
authors.initials: J
authors.lastname: Dresp
authors.forename: Peter
authors.initials: P
authors.lastname: Wiedemann
authors.forename: Horst
authors.initials: H
authors.lastname: Laqua
mesh_terms: D002849:Chromatography, Gas; D004058:Diffusion; D004322:Drainage; D005466:Fluorocarbons / Q000737:chemistry*; D006801:Humans; D012163:Retinal Detachment / Q000601:surgery; D012167:Retinal Perforations / Q000601:surgery; D012827:Silicone Oils / Q000737:chemistry*; D012995:Solubility; D014783:Viscosity
chemical_list: D005466:Fluorocarbons; D012827:Silicone Oils