title: Laser scanning analysis of cold cataract in young and old bovine lenses.
abstract: OBJECTIVE
  This research involves the use of a laser scanning instrument to evaluate the formation of cold cataracts in young and older bovine lenses.
  
  
  METHODS
  Bovine lenses from 18 (n=14) week old calf eyes and approximately 10 (n=7) year old animals were extracted in a sterile environment. The lenses were placed in a specialized glass chamber with temperature controlled circulating culture medium. The temperature cycle inside the chamber started at 37 degrees C, slowly cooled to 4 degrees C, and then warmed back up to 37 degrees C. A laser scanning system (ScanTox) was used to analyze the optical quality of bovine lenses during a cooling and warming cycle.
  
  
  RESULTS
  The relative light transmittance was measured as a function of pixel excitation caused by refracted beams and compared to pre-treatment measures. Each lens from each age group showed a significant decrease in transmittance at 4 degrees C, which recovered when the lenses were warmed to 37 degrees C. Lenses from young eyes showed less loss of refracted beam intensity than lenses from older eyes (32% versus 34%), although the difference was not significant.
  
  
  CONCLUSIONS
  The results of the present study indicate cold cataracts can be induced in both old and young bovine lenses, as shown by using a scanning laser instrument.
authors.affiliation: School of Optometry, University of Waterloo, Waterloo Ontario, Canada.
authors.forename: Alice
authors.initials: A
authors.lastname: Banh
authors.forename: Jacob G
authors.initials: JG
authors.lastname: Sivak
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002386:Cataract / Q000175:diagnosis / Q000209:etiology* / Q000378:metabolism; D002417:Cattle; D003080:Cold Temperature / Q000009:adverse effects*; D003459:Crystallins / Q000378:metabolism; D005615:Freezing; D007834:Lasers; D007908:Lens, Crystalline / Q000378:metabolism* / Q000473:pathology
chemical_list: D003459:Crystallins