The purpose of this study is to investigate how much selective trabeculoplasty (SLT) influences intraocular pressure (IOP) fluctuations measured with iCare Home rebound tonometry (RTHome) in patients with primary open-angle glaucoma (POAG) or pseudo-exfoliation glaucoma (PEX).

Sixty glaucoma patients (POAG and PEX) planned for SLT will be recruited.

At baseline, patients will be trained to use the iCare Home tonometer, a handheld device based on rebound tonometry and designed for patients to use at home. After the training session and when patients feel confident, a measurement will be recorded. Thereafter, a new measurement will be obtained by the study staff (an optometrist or a nurse) using the same device. No IOP values will be visible for the examiner at that point. Thereafter, a single IOP measurement will be obtained by the same study staff using Goldmann applanation tonometry (GAT). Patients will then borrow the iCare Home tonometer to meaure their IOP at 06 and 10 am, and at 2, 6 and 10 pm during three consecutive days to obtain an IOP curve. Patients will come for a second visit where new measurements will be made in the same way as at baseline.

Two months after SLT, a new IOP curve will be obtained following the same procedure as pre-operatively. Patients' daily activities (diet, motion or sleeping habits) will not be controlled.

Inclusion Criteria:

• POAG
• PXG

Exclusion Criteria:

• previous SLT
• reduced hand and arm mobility (e.g. due to rheumatism)

Consecutive male and female patients, older than 18 y.o., at St Erik's Eye Hospital in Stockholm, Sweden, diagnosed with POAG or PXG and listed for a SLT.