The Reister Tonometer is a handheld instrument designed for the precise measurement of intraocular pressure. It employs the applanation principle, where a small flat disk gently touches the cornea to determine the pressure within the eye. The instrument is named after its inventor, Swiss ophthalmologist Dr. Emil Huber Reister, who developed the tonometer to provide a more accurate and reliable method for IOP measurement. Gently place the tonometer on the cornea, ensuring proper alignment. The device's flat disk should make even contact with the cornea for accurate readings. For reliability, it is common to take multiple measurements and calculate an average to account for potential variations. The Reister Tonometer stands as a reliable and widely used tool for measuring intraocular pressure, contributing significantly to the diagnosis and management of ocular conditions. With its precision, ease of use, and portability, it continues to be an integral part of comprehensive eye care, aiding clinicians in providing optimal treatment for their patients, particularly those at risk for or diagnosed with glaucoma. Proper training and adherence to best practices ensure accurate and consistent results, promoting better eye health outcomes.Top of Form