What is the normal difference in intraocular pressure between the two eyes?

Under normal circumstances, an intraocular pressure difference of no more than 5 mmHg between the two eyes is considered normal. The following provides a detailed explanation:

The intraocular pressure difference refers to the variation in pressure within the two eyeballs. Generally, in healthy individuals, the pressure difference between the two eyes does not exceed 5 mmHg. However, due to differences in individual physical conditions and duration of eye use, this value may fluctuate slightly and is not fixed. If there are no other abnormal symptoms, such fluctuations are usually considered normal. If the intraocular pressure difference exceeds 5 mmHg, it indicates elevated pressure within the eye, which may be caused by factors such as eye strain or inflammatory stimulation. Prolonged eye use can lead to abnormal dilation of blood vessels inside the eye, while conditions like conjunctivitis can cause inflammation factors to stimulate soft tissues, increasing tissue fluid and accelerating blood flow—both of which may result in an abnormally high pressure difference between the two eyes. It is recommended to visit a hospital for further related examinations to receive appropriate treatment based on the underlying cause.

In daily life, it is important to manage eye usage time wisely. Avoid reading or using electronic devices in dim lighting, and refrain from touching the eyeball directly with hands to prevent bacteria from entering the eye. If a significant difference in intraocular pressure between the two eyes is detected, prompt medical evaluation and further treatment at a hospital are essential.