Low intraocular pressure, in the case of primary hypotony, is clinically rare, the cause is unknown, and may be genetically related. Normal eye tissues and function without any uncomfortable symptoms do not require treatment. Most patients have secondary hypotony, which is caused after eye trauma, surgery or eye disease, and may experience varying degrees of vision loss and soreness and swelling of the eye. If the eye pressure is low for a long time, it may cause changes in the structure and function of the eye, such as corneal edema manifesting as cloudy black eyes, or accompanied by congestion in the eyes. In addition, routine eye examinations reveal cloudy crystals, cloudy vitreous, folds and edema in the fundus, choroidal detachment, etc. Therefore, if not treated in a timely and symptomatic manner, it is likely to lead to atrophy of the eye and complete blindness.