The Agreement of Intraocular Pressure Measurement in Healthy Merinos Sheep Using Rebound Tonometer (Tonovet®) and Applanation Tonometer (Tono-Pen VetTM)

The assessment of intraocular pressure (IOP) holds significant importance in ophthalmology as a crucial diagnostic tool for various ocular disorders. This study aimed to evaluate the agreement between rebound (TonoVet®, TV) and applanation (Tono-Pen Vet™, TPV) tonometers in measuring IOP in healthy Merino sheep. 155 healthy Merinos (80 males, 75 females) with a mean weight of 54.4±8.7 kg, aged 24±6 months, were included in the study. IOP was measured between 9:00 and 11:00 am using both the rebound and applanation tonometers. The rebound tonometer was used first, followed by the applanation tonometer. A total of 620 readings (310 readings for each tonometer) were obtained from the two devices. No statistical differences were noted between the mean IOP measurements of the right and left eyes for both tonometers (p>0.05). However, there was a significant difference in the mean IOP measurements between the TV (11.8±2.3 mmHg) and the TPV (13.9±2.9 mmHg) tonometers (p