The pressure of the contents of the eye acting on the wall of the eye is called IOP. The statistically normal range of IOP is 10 to 21 mm Hg. IOP is measured by finger pressure measurement and by ophthalmometry. In general, IOP is increased in patients with glaucoma. 1, finger measurement method (finger measurement method) Let the patient gaze down at both eyes, the doctor will put the tip of the index finger of both hands on the skin surface of the upper lid, the two fingers alternately lightly press the eyeball, estimate the hardness of the eye, the normal IOP is recorded as Tn, with T+l, T+2, T+3 indicates mild, moderate or severe increase in IOP; with T-l, T-2, T-3 indicates mild, moderate or severe decrease in IOP. Patients can sometimes roughly determine high, moderate, or low IOP by touching their forehead, nose tip, and lips with their index finger. If the touch is like the tip of the nose, it is basically normal. 2, IOP meter measurement method Schiotz IOP meter and non-contact IOP meter measurement are commonly used in China. The former requires the patient to lie on his back with a low pillow and a drop of 0.5% to 1% bupivacaine or 1% to 2% lidocaine for surface anesthesia. The IOP meter pointer is calibrated to zero on the test plate and the base plate is disinfected. The patient is asked to look forward with both eyes fixed so that the cornea is kept in a median position. The surgeon holds the tonometer in the right hand and separates and fixes the upper and lower lids with the left hand. The base plate of the tonometer is placed vertically in the center of the cornea and the pointer scale is observed. When the measurement is completed, antibiotic eye drops are placed into the conjunctival sac and the patient is instructed not to rub the eye. Recording method: expressed as a fraction, for example, the weight is 5.5 g, the scale reading is 4, and the value of the conversion table is 20.55 mmHg, then the record is 5.5/4 = 20.55 mmHg. Schiotz tonometer is indentation type, and its measurement value is affected by the hardness of the eye wall. The non-contact IOP meter uses air pulse measurement, which is fast and avoids cross infection caused by contact with the cornea, but the measurement value is not accurate enough. the Goldmann IOP meter is indentation type, and the measurement is not affected by the hardness of the eye wall, which is more accurate. it is the current international standard IOP meter, which is rarely used in China.