The Effects of Intense Pulsed Light on Tear Osmolarity in Dry Eye Disease

Purpose: In this prospective study we show the influence of Intense Pulsed Light Therapy (IPL) on tear osmolarity, an increasingly important metric of dry eye disease. Previous studies have measured the effectiveness IPL has had on other metrics including tear break up time (TBUT), lipid layer grade (LLG), tear evaporation rate (TER), tear meniscus height (TMH), and subjective responses from patients. Methods: Single center prospective study included 16 patients and 32 eyes. Patient ages ranged from 18 to 90 years old with 75% of participants being female. All patients had an at least one eye with a tear osmolarity of 308 mOsm/L or greater, or had an inter-eye difference in tear osmolarity of 11 mOsm/L or greater. Tear osmolarity was measured bilaterally before a single IPL treatment followed by one drop of topical NSAID. Bilateral tear osmolarity was then measured again one month later. Results: Average tear osmolarity pre-treatment OD was 309 mOsm/L and OS was 306.75 mOsm/L. Average tear osmolarity post-treatment was OD 296.75 mOsm/L and OS 296.06 mOsm/L. Paired t tests were performed showing the change in tear osmolarity to be statistically significant in each eye, OD p=0.0029 and OS p=0.0011. Average inter-eye difference in osmolarity went from 11.81 mOsm/L to 6.81 mOsm/L, statistically significant with p=0.0148. Conclusions: A statistically significant decrease in tear osmolarity from abnormal to normal range as well as a reduction in inter-eye difference demonstrates an improvement in tear film quality after one treatment with IPL, thus suggesting IPL's effectiveness at treating dry eye disease.