Individual patients may experience elevated intraocular pressure after ICL implantation surgery, which is explained here. Generally speaking, transient acute IOP elevation after surgery is usually due to intraoperative viscoelastic residue, which is usually relieved within 24-48 hours by temporary IOP lowering treatment, so patients should not worry too much. The exception is a special case where the width of the ICL is significantly wider than the width of the patient’s ciliary sulcus to ciliary sulcus, resulting in acute angle-closure glaucoma caused by a high ICL arch, where the secreted atrial fluid cannot be discharged through the atrial angle but flows into the vitreous, leading to a vicious circle. These are the most common causes of elevated IOP within 24 hours after surgery. If IOP is normal on the first postoperative day and normal a week after surgery, but then slowly rises after 1 week, you usually need to pay attention to the presence of hormonal glaucoma. Because highly myopic patients are hormone-sensitive, they are prone to IOP elevation after using hormonal eye drops and therefore need to be aware of it. If elevated IOP is detected, the medication should be discontinued promptly and IOP-lowering treatment should be given. The literature reports that the average IOP after ICL implantation usually peaks around one month, so patients should pay special attention to follow the doctor’s instructions for regular follow-up. In addition, there are some special cases. Very rarely, patients who have undergone YAG laser iridostomy will experience recurrent episodes of perirhinal hole occlusion, resulting in elevated IOP. This condition requires removal of the ICL if repeated treatment is ineffective.Urrets-Zavalia syndrome: intermittent pupillary block with a sharp increase in IOP, resulting in ischemia of the iris sphincter and an inelastic pupil, and the patient’s pupil is dilated. In this case, the ICL can be removed without consideration, and conservative treatment with some NSAID drugs such as Pernambuccin and Diflucan, together with YAG laser to enlarge the circumferential cut hole, will usually improve.