Cataracts left unoperated for a long time may induce lens dissolving glaucoma, allergic uveitis and secondary glaucoma by the over mature stage, which may lead to permanent irreversible visual impairment. As we all know, cataracts cannot be put off all the time without surgery. So, when is the most appropriate time for cataract patients to have surgery?
If we use one sentence to explain it, it is: for all types of cataracts, as long as the vision loss affects the life, it is time to operate, without waiting for the so-called “maturity”.
Why do some people have the concept that “cataracts must be mature before they can be operated on”? This begins with the history of cataract surgery equipment and technology. From the 1960s to the 1980s, before ultrasound emulsifiers were perfected, cataract surgery was generally performed by making a large incision (1/2 the circumference of the cornea) in the eye to open the eye, freezing the cloudy lens and its capsule with a freezing tip and then pulling it off. If the cataract is not mature, it will take longer time to freeze it, which will increase the risk of surgery; moreover, if the suspensory ligament of the lens is not loose enough, it will be difficult to pull it off. Therefore, ophthalmologists at that time would generally advise cataract patients to wait until the mature stage before undergoing surgery.
After several decades, cataract surgery techniques and equipment have been updated and perfected. Since the 1990s, when cataract ultrasonic emulsion aspiration combined with IOL implantation became popular worldwide, the safety and effectiveness of cataract surgery have been greatly improved, and patients do not have to wait until they are completely blind before undergoing surgery. Cataract patients no longer have to endure the pain of not being able to see for a long time or even not being able to see.
Generally speaking, if the best corrected visual acuity with glasses is below 0.5 due to cataract, the ophthalmologist will recommend the patient to have surgery; if the visual acuity is below 0.3, early surgery will be recommended. In developed countries, even corrected visual acuity of 0.8 or 1.0 will be performed by experienced physicians as long as there is a decrease in contrast sensitivity and the patient subjectively requests surgery.
Although cataract is a major surgery in ophthalmology because it is, after all, an inner eye surgery. However, because the ultrasound emulsifier has been very well developed, the stability of the anterior chamber can be well maintained during surgery, and other related auxiliary techniques and equipment are very well matched, the surgical incision can be controlled to about 3mm or even smaller, and the surgery can be completed under the conditions of anterior chamber confinement without opening the eye during the surgery, so modern small incision ultrasound emulsion cataract surgery is very safe. Moreover, because cataract cannot be controlled and cured by medication under existing conditions, surgery is the only effective treatment option, so patients with cataract are advised to undergo surgery when appropriate.