Diurnal variation of corneal sensitivity

Abstract

Corneal sensitivity in young adults was measured at different times throughout the day. In one group measurements began in the morning and ended in the evening. In a second group one measurement was made in the evening and another the next morning. The results showed that corneal sensitivity was lowest in the morning and highest in the evening and that these findings were not due to habituation. An attempt is made to explain this fluctuation which is analogous to and may be related to that of the intraocular pressure. The corneal oedema when the subject is asleep may also help to account fox this fluctuation.