For tonometry is :
Tonometry is the method of measuring intraocular pressure using calibrated instruments. The normal range is 10 to 21 mm Hg.Schiotz tonometry, a drop of surface anaesthetic solution like 4%xylocaine is used. Ref :Greenberg R.D., Daniel K.J. (2011). Chapter 31. Eye Emergencies. In R.L. Humphries, C. Stone (Eds), CURRENT Diagnosis & Treatment Emergency Medicine, 7e.
4% xylocaine
3% xylocaine
2% xylocaine
1% xylocaine