title: Less Invasive Corneal Transepithelial Electrical Resistance Measurement Method.
abstract: OBJECTIVE
  To evaluate acute corneal permeability changes after instillation of benzalkonium chloride (BAC) using a newly developed in vivo less invasive corneal transepithelial electrical resistance (TER) measurement method in animals and humans.
  
  
  METHODS
  We previously developed an in vivo method for measuring corneal TER using intraocular electrodes in animals. This method can be used to precisely measure the decline of the corneal barrier function after instillation of BAC. To lessen the invasiveness of that procedure, we further refined the method for measuring the corneal TER by developing electrodes that could be placed on the surface of the cornea and in the conjunctival sac instead of inserting them into the anterior chamber. Corneal TER changes before and after exposure to 0.02% BAC were determined in this study using the new device in both rabbits and humans.
  
  
  RESULTS
  There was a significant decrease in the corneal TER after exposure of the cornea to 0.02% BAC solution in both rabbits and humans (P<.01). The results of this new less invasive method agreed with those of formerly established anterior chamber methods in rabbit experiments.
  
  
  CONCLUSIONS
  This new less invasive corneal TER measurement method enables us for the first time to measure TER of the human cornea, allowing safe and reliable investigation of the direct effect of different eye drop treatments on the corneal epithelium.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan. Electronic address: uematsu1124@outlook.jp.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Uematsu
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan; Department of Ophthalmology, EL-Minia University Hospital, EL-Minia, Egypt.
authors.forename: Yasser Helmy
authors.initials: YH
authors.lastname: Mohamed
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Onizuka
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Ueki
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Inoue
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Azusa
authors.initials: A
authors.lastname: Fujikawa
authors.affiliation: Department of Hospital Pharmacy, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Sasaki
authors.affiliation: Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitaoka
mesh_terms: D000818:Animals; D001548:Benzalkonium Compounds / Q000493:pharmacokinetics*; D002463:Cell Membrane Permeability / Q000502:physiology*; D017097:Electric Impedance; D019573:Epithelium, Corneal / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D011310:Preservatives, Pharmaceutical / Q000493:pharmacokinetics; D011817:Rabbits
chemical_list: D001548:Benzalkonium Compounds; D011310:Preservatives, Pharmaceutical
keywords: benzalkonium chloride; cornea; transepithelial electrical resistance