Two patterns of the relationship between tonographic pressure and the facility of outflow have been shown using constant pressure applanation tonography. In one facility is constant, in the other facility decreases as pressure increases. The reason for the decrease in facility is not known.
Moses RA. Constant Pressure Applanation TonographyIII. The Relationship of Tonometric Pressure to Rate of Loss of Ocular Volume. Arch Ophthalmol. 1967;77(2):181-184. doi:10.1001/archopht.1967.00980020183007