The definition and diagnostic criteria of dry eye disease (DED) proposed by the Japan Dry Eye Society and other countries are reviewed. The first definition and criteria of DED in Japan were proposed in 1995. In that report, DED was considered a disease of tears, which subsequently damaged ocular epithelia. The presence of subjective symptoms was not included in the criteria. In 2006, a new definition proposed that interactions between the tear film and ocular surface epithelia play important roles in DED. The presence of subjective symptoms, including visual disturbances, changes in tears, and epithelial damage were proposed to be major components of DED, and eyes positive for all three components were diagnosed as “definitive dry eye.” A third version was proposed in 2016, which emphasized unstable tear films as a core finding in DED. Following this guideline, eyes with an abnormally low tear film breakup time and the presence of subjective symptoms are considered to have DED. The current definition and criteria are different from those proposed in other countries. For example, the recently published DED definition by the Dry Eye WorkShop II (DEWS II) of the Tear Film and Ocular Surface Society (TFOS) focuses more on the underlying pathogenesis of DED, including inflammation, hyperosmolarity of tears, and neurosensory abnormalities, as well as unstable tear films.

Purpose: To present the results of a national survey on bullous keratopathy (BK) in Japan. Methods: A cross-sectional national survey was conducted for 963 eyes with BK seen between 1999 and 2001 by members of the Japan Cornea Society. Demographic characteristics, type of surgery, complications, and postoperative outcome were analyzed. Results: BK accounted for 24.2% (963 eyes) of total keratoplasties performed during the period. Graft clarity was maintained in 77.4% of cases, and immunologic rejection and elevated intraocular pressure was noted in 10.8% and 15.3%, respectively. Cataract surgery was the most common cause of BK (n = 428, 44.4%), and phacoemulsification and aspiration were performed in approximately 40% of cases. BK secondary to laser iridotomy (LI) was the second most common cause of BK (n = 225, 23.4%). LI was performed as a prophylactic measure in approximately one half of these cases. BK developed with a mean duration of 6.8 years after LI. Fuchs dystrophy was the cause of BK in 18 eyes (1.9%). Conclusions: The causes of BK in Japan are considerably different from those in other Western countries. LI-related BKs showed a remarkably high number, whereas Fuchs dystrophy was observed only rarely.

This study aimed to investigate the actual use of eye drops for dry eye disease (DED), the reasons for instillation behavior, and the relationship between instillation behavior and subjective symptoms. This web-based cross-sectional study collected data on instillation behavior, medication instruction, reasons for instillation behavior, and subjective symptoms. In total, 2645 participants were enrolled. The proportion of participants who instilled at the frequency specified in the package insert (the specified frequency) was 10.2%. The most common reason for not instilling at the prescribed frequency was as-needed instillation to alleviate subjective symptoms, and 61.3% of participants instilled when feeling symptoms. The improvement in the subjective symptoms score was significantly greater in the group that regularly instilled at the specified frequency than the other group (p = 0.0027), and patients in the other group were younger and had a higher rate of contact lens use and over-the-counter eye drops use. In conclusion, most participants did not instill the DED eye drops at the specified frequency to alleviate symptoms. In order to obtain the appropriate effect of eye drops, ophthalmologists need to impress upon patients the importance of regular instillation at the frequency specified in the package insert, while taking into account patient characteristics.