Cellular retention on diagnostic contact lenses: an evaluation of current cleaning protocol.
OBJECTIVE
To compare cellular contamination of diagnostic contact lenses after two different cleaning methods.


METHODS
Twenty-five used diagnostic contact lenses were cleaned by two different methods and the material retained on their contact surface examined for cells. Two diagnostic contact lenses were examined using electron microscopy and surface debris was subjected to x-ray photoelectron spectroscopy.


RESULTS
Significantly more cells were present on used lenses compared with controls (P<0.001). There was no significant difference in total cell count between the lenses subjected to the two cleaning strategies but the lenses simply wiped clean retained marginally more nucleated cells than controls (P=0.039). Electron microscopy showed the majority of the debris on or close to the rim of the lens. X-ray photoelectron spectroscopy confirmed the presence of proteinaceous material.


CONCLUSIONS
Regardless of cleaning method, significant cellular debris is retained on the surface of diagnostic contact lenses after use.
MacRae
M
M
Department of Opthalmology, Princess Alexandra Eye Pavilion, Chalmers Street, Edinburgh, UK. mary.macrae@doctors.org.uk
Bax
G
G
Dhillon
B
B
D002452:Cell Count; D003261:Contact Lenses; D003315:Cornea / Q000166:cytology; D003666:Decontamination / Q000379:methods*; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation; D004202:Disinfectants / Q000494:pharmacology; D004577:Electron Probe Microanalysis / Q000379:methods; D004847:Epithelial Cells / Q000166:cytology; D004866:Equipment Contamination; D017743:Equipment Reuse; D006801:Humans; D008855:Microscopy, Electron, Scanning; D012973:Sodium Hypochlorite / Q000494:pharmacology; D013499:Surface Properties
D004202:Disinfectants; D012973:Sodium Hypochlorite