Intraocular pressure changes following topical ocular hypotensive medications washout

Background To review the changes in intraocular pressure (IOP) following topical hypotensive medications washout in patients with primary open angle glaucoma (POAG), ocular hypertension (OHT) and uveitic glaucoma (UG)/OHT. Methods The study included 120 patients with POAG, OHT and UG recruited from prospective clinical trials between February 2013 and July 2017. We excluded 20 eyes with IOP of ≤21 mm Hg, 11 eyes with previous incisional surgery and 17 eyes with incomplete data. UG eyes with active inflammation and on steroid treatment were excluded. Participants underwent a 1-month washout period from topical ocular hypotensive medications before IOP phasing. Comparisons were made between pre/post-washout IOP, and highest-recorded (peak) and post-washout IOP. Results A total of 110 eyes with POAG, 33 eyes with OHT and 43 eyes with UG were included for analysis. The mean pre-washout IOP was 18.1±3.3 mm Hg in POAG, 18.8±3.3 mm Hg in OHT and 17.9±8.8 mm Hg in UG; the mean post-washout IOP was 26.6±4.8 mm Hg, 26.4±3.9 mm Hg, 23.1±10.1 mm Hg in POAG, OHT and UG, respectively. The mean increase in IOP after washout was significantly lower in UG compared with POAG and OHT eyes (p=0.01). The percentage of eyes with post-washout IOP <22 mm Hg was 12.7% in POAG, 6.1% in OHT and 51.2% in UG. Conclusion Active inflammation and steroid treatment contributes to elevated IOP in uveitis. Therefore, IOP may revert to normal once inflammation subsides. We recommend ocular hypotensive treatment washout to be considered in UG eyes that have IOP under control in the absence of recurrence of uveitis.