Mansouri K, Gillmann K, Rao HL, et al. - Researchers conducted this prospective, open-label, multicentre observational study to better understand seasonal and weekday intraocular pressure (IOP) variations, long-term daily IOP measurements were evaluated in glaucoma patients using an intraocular telemetric sensor. The IOP variation patterns were analyzed in 22 patients (22 eyes) with primary open-angle glaucoma (67.8 ± 6.8 years, 36.4% female) who had undergone placement of an intraocular telemetric sensor at the time of cataract surgery. Each enrolled patient recorded daily measurements of IOP for an average duration of 721 days. This research confirms previously observed changes in the seasonal IOP. IOP in winter was significantly higher than in summer months. IOP was also lower on Friday relative to other days. The rationale for these results is unclear.