Which instrument is rebound tonometer that does not require proparacaine?

• A. Tonopen
• B. Tonovet
• C. Pascal tonometer
• D. Schiotz tonometer

Answer: (B)

Rebound tonometry uses a tiny, lightweight probe that briefly contacts the cornea and then rebounds. The measurement relies on the probe’s deceleration and rebound behavior after a light touch, so the contact is very short and gentle. Because the interaction is so brief, corneal sensation is minimal and topical anesthesia is usually not required, making it quick and well tolerated, even in children or uncooperative patients.

Tonovet is the rebound tonometer designed for this approach and is typically used without proparacaine, giving rapid IOP readings without the need for anesthetic.

Other common tonometers involve longer or stronger corneal contact. Tonopen uses applanation, which tends to cause more discomfort and usually requires topical anesthesia. Pascal tonometer involves contact-based pressure sensing that also requires anesthesia. Schiotz tonometer is an indentation method with a plunger and weights, which similarly necessitates anesthesia for comfort and accuracy.

So, the rebound tonometer that does not require proparacaine is Tonovet.