Laser-induced damage to transparent polymers: chemical effect of short-pulsed (Q-switched) Nd:YAG laser radiation on ophthalmic acrylic biomaterials. II. Study of monomer release from artificial intraocular lenses.
Commercial intraocular lenses and polymer specimens, both poly(methyl methacrylate) (PMMA) and poly(2-hydroxyethyl methacrylate) p(HEMA), were subjected to various levels of irradiation from a Q-switched Nd:YAG laser, and then to extraction and sample-enrichment techniques. The extracts were analysed by capillary gas chromatography. In PMMA samples, residual contents of 0.05-0.89% (wt) MMA were found and it appeared that the laser radiation did not cause a detectable increase of the monomer content. No residual HEMA could be found in p(HEMA) samples before or after laser bombardment. It is concluded that the accidental exposure of lenses to Nd:YAG laser cannot produce a significant release of monomers. Depolymerization induced by laser is a process unlikely to occur at the energy levels used in ophthalmic surgery.
Lions Eye Institute, Nedlands, Western Australia.
T V
TV
Chirila
G D
GD
Barrett
A V
AV
Russo
I J
IJ
Constable
P P
PP
van Saarloos
C I
CI
Russo
D008401:Gas Chromatography-Mass Spectrometry; D007834:Lasers; D007910:Lenses, Intraocular; D008422:Materials Testing; D008768:Methylmethacrylates / Q000032:analysis / Q000528:radiation effects*; D011102:Polyhydroxyethyl Methacrylate / Q000032:analysis / Q000528:radiation effects*; D011109:Polymethacrylic Acids / Q000528:radiation effects*
D008768:Methylmethacrylates; D011109:Polymethacrylic Acids; D011102:Polyhydroxyethyl Methacrylate