In patients with glaucoma, there is a possibility of their eye pressure either fluctuating significantly or being outside the target range (as determined by their doctor). Both these changes are associated with worsening of glaucoma. Monitoring for these changes between office visits can help reassure the doctor and the patient that the therapy is adequate and that the patient is compliant with treatment. If the eye pressure is not stable, then the doctor can recommend additional treatment or tailor the eye drop regimen to stabilize the pressure before permanent loss of tissue or visual field occurs.