Bit more Info: After a routine eye test at the local Optometrist the puff test gave my pressures at 26/26. The Optom advised me to see my doc and he referred me to an Opthamologist. He tested my eye preesures with the "blue light test" which presses against the eye to measure the pressure and is considered much more accurate than the puff test. (And gave the pressures as 21/21) He also measured the thickness of my corneas. If they are thicker than normal then they are stiffer than normal and the pressure test will overread (and Vice versa for thinner than normal corneas.). Apparently the rule of thumb is that for every 50um > or< than 560um the thickness of the cornea is then the indicated pressures are reduced/increased by 2.5mmHg. (Bit like IAS/TAS) (This brought my actual pressures down to about 18/18)