TY  - JOUR
PY  - 1977//
TI  - Material and thickness: the important factors in the impact resistance of spectacle lenses
JO  - Canadian journal of ophthalmology
A1  - Christianson, M. D.
A1  - Parker, J. A.
A1  - Arndt, J.
SP  - 300
EP  - 303
VL  - 12
IS  - 4
N2  - The identify the population at risk of permanent visual impairment from injuries associated with spectacles, we analysed 446 cases of penetrating ocular injury occurring over a ten year period. Sixteen injuries (3.6%) were due to spectacles; 40% of these were adult male amateur athletes. We used the drop-ball test to determine the important factors in the resistance to impact of 177 used spectacle lenses (29 plastic C39, 40 heat-tempered glass, 108 non-tempered glass). We found that material and thickness were the most important. The plastic lenses were the most impact resistant and non-tempered glass lenses the least, with heat-tempered glass lenses falling between. Plastic lenses of adequate centre thickness mounted in plastic frames are recommended for all children and all adults involved in athletics.<p /> <p>Language: en</p>
LA  - en
SN  - 0008-4182
UR  - http://dx.doi.org/
ID  - ref1
ER  -