Recently, researchers at Columbia University in the United States have developed a new method for correcting vision with laser. It can solve various problems such as myopia, hyperopia and astigmatism without any invasiveness, and is safer and more convenient than the previous methods. At present, relevant research results have been published in the British journal Nature Photonics.
In recent years, more and more people have used laser pointer vision correction surgery, which uses laser to “cut” the cornea, which is located at the forefront of the eye, to change the curvature of the cornea in the pupil area and adjust the refractive performance. Wang Chao, the first author of the paper and a Chinese student at Columbia University, said that no matter how minimally invasive laser vision correction, it is an invasive surgery. The problem of adverse reactions and restrictions on population use is still obvious. If clinically proven, this new technology is expected to replace existing laser-corrected vision surgery.
The most advanced laser vision correction surgery is to use a femtosecond laser to process the cornea. Unlike the prior art, the new study does not use the femtosecond laser as a “knife”, but rather acts as a stimulus to cause the cornea to deform itself.
The researchers controlled the intensity of the femtosecond laser to a certain extent without cutting or burning the corneal tissue. Under certain conditions, the femtosecond laser pointer contacts the cornea and undergoes a series of photochemical reactions that ionize molecules such as water inside the cornea, producing a low-density plasma that generates oxygen-containing free radicals. These free radicals react with the collagen fibers in the cornea, producing a wonderful cross-linking effect that causes the cornea to change shape. The use of femtosecond lasers to produce photochemical effects eliminates the need for photosensitizers, does not cut the cornea, and does not harm tissues and cells. It is a true non-invasive technique. Currently, the technology is being evaluated by the US Food and Drug Administration and is scheduled to begin clinical trials by the end of this year.