Factors associated with 1-year outcomes and transient intraocular pressure elevation in minimally invasive glaucoma surgery using Kahook Dual Blades

In this retrospective case–control study, we aimed to investigate the mid- to long-term outcomes and factors involved in minimally invasive glaucoma surgery using the Kahook Dual Blade. Of the 229 cases since 2018 in which the dual blades were used for glaucoma surgery at the Tenri Hospital, 133 eyes of 98 patients who followed up for more than 3 months were included. Intraocular pressure (IOP), number of drops score, and need for reoperation were evaluated on day 1 and at 1, 3, 6, 9, and 12 months postoperatively. Intraocular pressure spikes occurred in 25 patients postoperatively (18.8%), occurring at approximately 4.5 days (1–10.25). The preoperative number of eye drops used and ocular axial length were found to be associated with the occurrence of spikes (OR = 1.45, 95% CI 1.02–2.06; P = 0.025 and OR = 1.41, 95% CI 0.98–1.25; P = 0.072, respectively). At the 12-month mark, no significant relationship was found between the presence of spikes or incisional extent scores and the amount of change in IOP and number of drops scores. Patients with severe visual field impairment, high preoperative IOP and drop scores, and long ocular axial length may require more frequent follow-ups after surgery to check for spikes.