Article

Preoperative opacification of acrylic intraocular lenses in storage.

School of Chemical and Pharmaceutical Science, Kingston University, Penrhyn Road, Kingston Upon Thames, Surrey, KT1 2EE, United Kingdom.
Journal of Materials Science Materials in Medicine (Impact Factor: 2.38). 05/2007; 18(4):583-9. DOI: 10.1007/s10856-007-2305-5
Source: PubMed

ABSTRACT The preoperative opacification of acrylic intraocular lenses (IOLs) was investigated in order to determine its cause. Opacified IOLs were examined by energy dispersive X-ray (EDX), the buffer solutions were analysed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and the rubber seals used in the bottles in which the IOLs were stored were ashed and tested. The deposit covering the opacified lenses contained a significant amount of zinc, which was absent from fresh IOLs and buffer solution. The source of this was found to be the rubber seals used to seal the glass bottles in which the IOLs were stored. There were two types of rubber seals used, red and grey in colour. The buffer solutions in which opacification had occurred was also contaminated with zinc, but this was only noticeable when using the red seals. This contamination was reproduced by boiling red seals in fresh buffer solution for eighty minutes, to simulate autoclaving. It was concluded that zinc from the zinc oxide used as filler in the rubber seals was leaching into the buffer solution and causing the IOLs to become opacified. This was found to be much worse in the case of the red seals than for the grey ones. However, minute crystals were found on the IOLs stored using the grey ones, which could potentially act as nucleation points for postoperative opacification.

0 Bookmarks
 · 
220 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the prevalence, severity, and visual significance of glistenings seen in the AcrySof intraocular lens (IOL) and determine whether a large in-depth study of this lens is warranted. John Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Patients who had the AcrySof IOL implanted at 1 institution over the past 4 years were serially selected. Forty-two eyes that had phacoemulsification with implantation of the AcrySof IOL were evaluated. The examination consisted of visual acuity, glare, contrast sensitivity, and dilated fundus and dilated slitlamp evaluations. Glistenings in the IOL were graded at the slitlamp from trace to 4+. All 42 IOLs had some degree of lenticular glistenings. The glistenings were graded as trace in 27 IOLs (64%), 1+ in 5 (12%), 2+ in 5 (12%), 3+ in 3 (7%), and 4+ in 2 (5%). The Snellen acuity in eyes with severe glistenings (> or = 2+) was one-half line lower than in eyes with mild glistenings (+) (P =.01). In all eyes, the Brightness Acuity Tester score was a little more than one-half line lower than the Snellen acuity, and the difference was 1 full line in eyes with glistenings graded above 2+. Fourteen of 15 IOLs (93%) with glistenings graded greater than trace had been in the eye for more than 1 year. There was no evidence that contrast sensitivity was affected by the glistenings. Glistenings occurred frequently in AcrySof IOLs, with most cases mild. A larger study of this lens is needed to determine whether severe presentations affect visual function and to understand how glistenings change over time.
    Journal of Cataract and Refractive Surgery 05/2001; 27(5):728-33. DOI:10.1016/S0886-3350(00)00700-8 · 2.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To examine the effect of temperature change on the structural alteration and glistening formation in an AcrySof intraocular lens (IOL). Department of Chemical Science and Engineering, Faculty of Engineering, Kobe University, Kobe, Japan. The equilibrium water content of a Wagon-Wheel-packaged AcrySof IOL was determined at various temperatures by the gravimetrical method. Alterations in the microscopic structure of the lens were analyzed in situ with a reflecting microscope without staining, while the temperature of the lens was changed at different rates. Microvacuoles of 1.0 to 20.0 microm formed in the bulk of a swollen AcrySof IOL as the temperature decreased. The morphology of the vacuoles was similar to that of glistening particles observed in vivo. The size and density of the glistening-like vacuoles varied depending on the magnitude and rate of the temperature decrease. The glistening-like vacuoles were imprinted in the bulk of the IOL during the preceding cooling process in aqueous humor. Glistenings formed in the bulk of an AcrySof IOL as the medium temperature decreased. The mechanism may involve spinodal decomposition of the swollen polymer network, which initiates the formation of microvacuoles consisting of water and loosely packed network chains.
    Journal of Cataract and Refractive Surgery 10/2001; 27(9):1493-8. DOI:10.1016/S0886-3350(01)00895-1 · 2.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the incidence and progression of small refractile vacuoles in a consecutive series of patients implanted with the Surgidev B20/20 (Surgidev Corporations, Goleta, California) polymethylmethacrylate intraocular lens. Observational case series. A 4-year prospective study of the progression of glistenings in patients implanted with the Surgidev B20/20 intraocular lenses. In a consecutive series of 51 patients (73 eyes) that received the Surgidev B20/20 intraocular lens onset, number, and location of intraocular lens glistenings, best-corrected visual acuity, and associated ocular pathology were noted. With mean follow-up of 98 +/- 27 months (range, 48 to 176 months), 65 of 73 (89%) eyes had intraocular lens glistenings. Glistenings increased in frequency and size with increasing follow-up (P =.001). Glistenings may occur in polymethylmethacrylate intraocular lenses with long-term follow-up, and they are progressive.
    American Journal of Ophthalmology 12/2001; 132(5):783-5. DOI:10.1016/S0002-9394(01)01090-X · 4.02 Impact Factor

Full-text

Download
74 Downloads
Available from
May 20, 2014

Colin Pratt