title: Effect of exposure to balanced salt solution upon the hardness of the crystalline lens.
abstract: BACKGROUND
  The nucleus confers most of the hardness upon the lens, water content decreases towards the centre of the nucleus and a relative dehydration accompanies increased hardness in some cataractous lenses. It is a possibility that exposure and incubation of the inner layers of the nucleus to balanced salt solution (BSS) can result in the softening of the nucleus.
  
  
  OBJECTIVE
  This study aimed to investigate the effect of BSS upon the lens hardness.
  
  
  METHODS
  Nuclear colour element of cataract was graded biomicroscopically. Following extracapsular cataract surgery the lens nucleocortex was divided into two equal parts and each half was allocated randomly to incubation in BSS or air for 5 min before the hardness of each section was assessed by an automated guillotine.
  
  
  RESULTS
  Following incubation with BSS the mean force necessary to bisect the lens was 0.50 N and in the control air group the mean force was 0.64 N. The lenses in the BSS-treated group were consistently softer than those in the control group, with a mean softening of 18.3% (P=0.001). The amount of softening was not related to the nuclear colour (P=0.6) or age (P=0.1).
  
  
  CONCLUSIONS
  Softening of the lens through physical disruption has previously been reported. This study describes the phenomenon of nuclear softening following exposure to BSS, indicating that lens softening can occur through biochemical means.
authors.affiliation: Department of Ophthalmology, St. George's Hospital, London, UK.
authors.forename: H
authors.initials: H
authors.lastname: Tabandeh
authors.forename: A
authors.initials: A
authors.lastname: Karim
authors.forename: G M
authors.initials: GM
authors.lastname: Thompson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004548:Elasticity / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D007908:Lens, Crystalline / Q000187:drug effects* / Q000503:physiopathology; D008875:Middle Aged; D018918:Phacoemulsification / Q000379:methods; D012965:Sodium Chloride / Q000494:pharmacology*
chemical_list: D012965:Sodium Chloride