1. Does high intraocular pressure indicate glaucoma? High intraocular pressure can indicate glaucoma, but it cannot be determined whether it is congenital or secondary, primary or mixed, which requires a clear diagnosis based on a comprehensive analysis of the clinical history and signs. Glaucoma cannot be ruled out even if the intraocular pressure is not high. Because there is a kind of glaucoma called normal intraocular pressure glaucoma. 2.What factors affect IOP? Factors affecting IOP include corneal thickness, optic disc sieve, intracranial pressure, emotion, body position, individual base pressure, etc. If you did not sleep well the day before, or drink a lot of water before the test, it will lead to inaccurate results of IOP measurement. 3.Do I need to measure corneal thickness before IOP measurement? Corneal thickness should be measured before the first IOP measurement (unless the corneal thickness has been measured correctly). Because the thickness of the cornea is positively correlated with the IOP, i.e. the thicker the cornea, the higher the IOP. 4.If the IOP is normal after consecutive measurements, does it mean that the IOP is not elevated? If the IOP is measured several times in a row and the results are normal, it does not mean that the IOP is not elevated, but we should pay more attention to the IOP amplitude. The IOP wave amplitude is more reflective of the characteristics of glaucoma. If the IOP wave amplitude exceeds 5mmHg, follow-up is needed; if the IOP wave amplitude exceeds 8mmHg, it is one of the diagnostic bases. 5.Reference value for glaucoma diagnosis The absolute value is not a reference value for glaucoma diagnosis, but its wave amplitude is a reference value for glaucoma diagnosis, and it is more a reference value for glaucoma efficacy assessment and controlling the degree of development during long-term monitoring of eye pressure, which is 1 or 2 times higher than the normal value. 6.Is it necessary to do IOP daily curve for glaucoma diagnosis? If you are diagnosed with glaucoma, you should also do the IOP daily curve and the IOP diurnal curve, which is helpful for guiding the time of medication of IOP-lowering drugs. Generally, we choose to do a 12-hour IOP curve as an outpatient or a 24-hour IOP curve as an inpatient. When glaucoma is poorly controlled, it is necessary to do 24-hour IOP curve in hospital. 7. Is there a big difference in IOP between both eyes? A large difference in pressure between the two eyes should be considered problematic. A pressure difference of more than 5 mmHg in both eyes requires follow-up; a pressure difference of more than 8 mmHg in both eyes is one of the diagnostic bases. Sometimes the IOP is high in the left eye and normal in the right eye, and sometimes it is the other way around, depending on the degree of IOP difference. IOP fluctuations within a certain range are normal, and IOP in normal people is not constant. IOP is fluctuating and curved like blood pressure, and appropriate fluctuations in IOP are within the normal range.