|
KMID : 1011420220270040253
|
|
Journal of Korean Ophthalmic Optics Society
2022 Volume.27 No. 4 p.253 ~ p.262
|
|
|
Effects of Repeated Exposure to Low Temperatures on Circle Soft Contact Lenses
|
|
Jung Won-Young
Yoon Sun-Mi
Lee Joo-Yeon
Kim So-Ra
Park Mi-Jung
|
|
|
Abstract
|
|
|
Purpose: This study aimed to find out the pigmentation patterns, elution, and changes in lens parameters that appear when a circle soft contact lens is exposed repeatedly to low temperatures.
Methods: Four types of circle lenses with different materials and pigmentation methods were repeatedly exposed 3 times: 24 hour-low temperature exposure at 0, ?10 and ?20°C and 2 hourroom temperature stabilization. After repeated exposure, the center thickness, refractive power, total diameter, base curve, visible light transmittance, and absorbance were measured. The pigmentation pattern and elution were observed through scanning electron microscopy and the difference was compared to the control group without low-temperature exposure.
Results: For three types of circle lenses except for etafilcon A, changes in pigmentation pattern and elution were observed from 0°C, and more distinct changes were observed with lower temperature exposure. Only in the hilafilcon B, was the absorbance higher at other temperatures during repeated exposure at ?20°C. The total diameter and base curve showed a change outside the tolerance range set by the Ministry of Food and Drug Safety (MFDS) when exposed to temperatures below 0°C in etafilcon A and hilafilcon B, and some significant changes were noted at 0°C and ?10°C. In the case of refractive power and visible light transmittance, some significant changes were observed due to the repeated low-temperature exposure but not consistent changes, all of which were within the MFDS tolerance range.
Conclusions: When repeatedly exposed to low temperatures according to the pigmentation method and material of the circle lens, a significant parameter change occurred from 0°C, and the total diameter and base curve exceeded the allowable error of the MFDS. Therefore, it is necessary to be careful not to fall below 0°C when storing and distributing circle lenses in winter and to create standards for storing and distributing circle lenses.
|
|
|
KEYWORD
|
|
|
Circle contact lenses, Repeated exposure to low temperatures, Pigmentation methods, Parameter changes
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|