Whenever I encounter patients with retinitis pigmentosa (RP) in the clinic, I am overwhelmed with pain: they watch this wonderful world disappear from their eyes little by little, but there is nothing they can do about it, and the pain is desperate; and as an ophthalmologist, I feel deeply guilty for being unable to do anything about it! Therefore, we have been working hard in the hope of finding the ultimate solution that can really save them from the darkness. The five technology systems (retinal transplantation, visual prosthesis implantation, drug therapy, stem cell and gene therapy) have been the most promising directions for future breakthroughs, and researchers all over the world are actively exploring them, and we are constantly seeing new breakthroughs. For example, it was recently reported that embryonic stem cells have artificially grown a prototype structure of the retina: Japanese researchers have artificially grown a prototype structure of the retina, the most complex physiological tissue ever artificially grown, using embryonic stem cells from laboratory rats, according to a new Nature article. Researchers at the Center for Developmental Biology at the RIKEN Institute of Science and Chemistry and other institutions report that embryonic stem cells from laboratory rats gradually and automatically formed a structure called the optic cup in a special culture medium. The optic cup is a retinal structure in the early stages of embryonic development, similar in shape to a wine glass, which gradually develops photoreceptor cells, nerve cells, and so on to form the retina. The researchers said the artificially grown optic cup is similar in structure to the naturally occurring optic cup, and the researchers are now testing the function of the artificially grown optic cup, i.e., to see if it can really sense light and transmit the relevant neural signals to the brain of the experimental rats. The eye is the most sophisticated organ in humans and many animals, and this research is the most complex physiological tissue ever artificially grown. If further research can confirm the function of the artificially cultivated optic cup, it will be very helpful for the research and treatment of ophthalmic diseases, such as providing solutions for repairing damaged retinas. We have been working hard on this!