유통시 노출 가능한 온도에서의 써클콘택트렌즈 표면 및 파라미터 변화

Purpose: In the present study, changes in the surface and parameters of circle contact lenses (cosmetic colored contact lenses, hereafter referred to as circle lenses) used for cosmetic purposes were investigated when the lenses were exposed to various changes of temperature during their distribution. Methods: Three types of sealed circle lenses were respectively placed at temperatures of −20, 20, 50, and 80°C for 4 hours, and subsequently stabilized for 20 hours; this procedure was repeated once, 3 times, and 5 times. Changes in the pigmentation pattern and parameters of the lenses were then measured. Results: The change of parameters was observed in all of the etafilcon A circle lenses made by using the sandwich method, and hilafilcon B and methafilcon A lenses with pigmentation on their surfaces; however, the degree of change caused by the different temperatures was different according to the type of circle lens. There were some cases in which a statistically significant change in each parameter was noted for each circle lens, and there were also parameters that exceeded the range of standard error stipulated by Ministry of Food and Drug Safety. The cracks of the pigmentation pattern and small holes were observed in a circle lens with the dye on its surface at −20°C, and the large or small aggregation of dye was observed at −80°C. Conclusions: In the present study, changes in the parameters and pigmentation pattern of circle lenses were found at different temperature conditions during distribution. These changes can cause problems related to vision and comfort. Thus, it is suggested that the establishment of the temperature standard for distributing lenses, and further evaluation of the stability against heat that may occur during the pigmentation process are necessary.