Equilibrium water content and glistenings in acrylic intraocular lenses

J Cataract Refract Surg. 2004 Aug;30(8):1768-72. doi: 10.1016/j.jcrs.2003.12.038.


Purpose: To investigate the possible relationship between temperature and water absorption in acrylic intraocular lenses (IOLs).

Setting: Laboratory setting, Miyata Eye Clinic, Hiroshima, Japan.

Methods: The equilibrium water content (amount of water absorbed per weight of the resin x 100) in 2 hydrophobic acrylic IOLs (AcrySof MA60BM [Alcon] and Sensar AR40 [AMO]) was calculated at 30 degrees C, 40 degrees C, and 50 degrees C. The 2 IOLs were also subjected to 3 changes in temperature: from 37 degrees C to 35 degrees C, 39 degrees C to 35 degrees C, and 41 degrees C to 35 degrees C. They were incubated in physiological saline at the higher temperature for 2 hours and at the lower temperature for 30 days before being examined for glistening formation.

Results: The water content was higher in the AR40 IOL than in the MA60BM IOL at all temperatures. A temperature-dependent increase in water content was seen in both IOLs, greater in the MA60BM. With a temperature change from 37 degrees C to 35 degrees C, glistening formation was not observed in either IOL. With a temperature change from 39 degrees C to 35 degrees C, glistenings were observed in the MA60BM IOL, and with a temperature change from 41 degrees C to 35 degrees C, they were observed in both IOLs.

Conclusion: The change in the equilibrium water content caused by temperature changes between 30 degrees C and 40 degrees C is an important factor in glistening formation, and thus an IOL featuring less temperature-dependent water absorption is less likely to form glistenings.

Publication types

  • Comparative Study

MeSH terms

  • Absorption
  • Acrylic Resins*
  • Hot Temperature*
  • Hydrophobic and Hydrophilic Interactions
  • Lenses, Intraocular*
  • Water / metabolism*


  • Acrylic Resins
  • Water