ICL (Implantable Collamer Lens) is an implantable posterior chamber type ophthalmic refractive lens, which is an exclusive patented product of STAARSurgical in Switzerland, and it is because of this exclusivity that the surgery is very expensive. It is used to correct various refractive errors and is a new generation of refractive surgery product that has attracted the attention of ophthalmologists in recent years. it received CE certification in Europe in 1997, FDA certification in the United States in 2005, and SFDA approval in China in 2006. The material of ICL intraocular implantable lens is Collamer’s patented collagen polymer, which has a refractive index of 1.453 at 35 degrees Celsius and its refractive properties are very similar to the natural lens in the human eye. The polymer absorbs UV radiation and blocks more than 90% of UV radiation with wavelengths below 387 nm. At the same time, the polymer material is biocompatible with the normal tissues in the eye and can remain stable in the eye for a long period of time, which is exactly what can dispel the doubts of many myopic patients. In addition, the ICL lens has an anti-reflective surface that makes its refractive index progressive, allowing patients to see both far and near more comfortably after surgery, and significantly reducing nighttime glare, which is unmatched by excimer laser surgery in the treatment of high myopia. Some older adults who have undergone cataract surgery and have an IOL implanted in their eyes can experience significant reflections at night when light hits their eyes from a particular direction. A similar situation does not occur with ICL lenses. No one will know that you have an IOL implanted in your eye if you do not tell them yourself. Location of ICL IOL in the eye: green is the iris, blue is the ICL So, what are the suitable people for ICL surgery? 1. Adults aged 21 to 50 years old; 2. The refractive error is stable with a change of less than ±50 degrees one year prior to surgery, which is consistent with excimer laser surgery; 3. The anterior chamber depth (ACD) of the eye is greater than or equal to 2.8 mm, which is the linear distance from the corneal endothelium to the anterior surface of the clear lens, and can be measured with the Dr. Lund Orbscan Eye Ganglion Analysis System, or It can be measured with the Ocullu Pentacam Eye Ganglion Analysis System, and the Eye Ganglion OCT System. Patients with an anterior chamber depth lower than 2.8 mm cannot receive ICL surgery; 4. Correction range: myopia 200 degrees to 2000 degrees, astigmatism 100 degrees to 500 degrees, hyperopia 100 degrees to 1000 degrees; 5. Patients with high refractive error, thin cornea, severe dry eye, and oversized pupils are not suitable for excimer laser surgery, but can receive ICL lens implantation. Who cannot undergo ICL surgery? Patients with a history of uveitis, uveitis, endophthalmitis, glaucoma, or cataract in either eye; 2. Patients with progressive vision-threatening diseases or retinopathy; 3. Patients with low corneal endothelial cell counts, corneal endothelial dystrophy, or other corneal pathologies; 4. Patients who are pregnant or breastfeeding; 5. Patients with psychological disorders. Before ICL surgery, what tests and preparations do patients need to do? 1.For the preoperative examination, it is necessary to stop wearing soft contact lenses for at least 7 days and hard contact lenses for at least 3 weeks; 2.Detail the history of ocular and systemic diseases to the surgeon; 3.Computerized optometry, primary optometry, dilated optometry with adequate ciliary muscle paralysis; 4.Naked eye visual acuity, best corrected visual acuity; 5.Corneal topography, corneal curvature examination, to obtain relevant data for calculating the ICL lens prescription; 6.Corneal thickness, corneal thickness, and corneal curvature. 6.Corneal thickness measurement; 7.Measurement of the anterior chamber depth of the eye, which can be measured with the Dr. Lund Orbscan anterior segment analysis system, or with the Ocullu Pentacam anterior segment analysis system or the OCT system of the anterior segment; 8.Intraocular pressure measurement; 9.Anterior chamber angioscopy to observe the anterior chamber angle of the eye for lesions; 10.Slit lamp microscopy to examine the cornea, anterior chamber, pupil, lens, etc, 11, fundus retinal examination, especially peripheral retinal examination, to understand whether there is retinal pathology; 12, accurate measurement of the white to white distance of the horizontal meridian of the cornea (i.e. corneal diameter data), can be measured directly with calipers under the slit lamp microscope, or magnifying glass, or can be measured with the Dr. Lund Orbscan analysis system, but the measurement results need to be compared with However, the measurement results need to be compared with the caliper measurements to exclude differences in the measurement results of different instruments. Also, improper calibration of calipers can lead to deviations. The surgeon must be very careful when performing this vital measurement, as the exact corneal diameter determines the effectiveness and safety of the ICL lens implantation. 13. Peripheral iridotomy (PI), a laser iridotomy is required one to two weeks prior to the ICL implantation procedure. The laser is an anterior preoptic YAG laser, which is used to make two circumferential incisions at 11:00 and 13:30 above the peripheral portion of the mid-iris, respectively, separated at a 90 degree angle, with a circumferential incision of at least 0.8 mm in diameter. Some experienced surgeons may also choose to perform a circumferential iris incision at the same time as the procedure is performed. At this point, the iris is removed peripherally using microscissors rather than a laser.