EyeWorld Asia-Pacific September 2020 Issue

40 EWAP SEPTEMBER 2020 CORNEA So-Hyang Chung, MD Professor, Seoul St. Mary’s Hospital, the Catholic University of Korea Seocho-Gu, Seoul, South Korea chungsh@catholic.ac.kr ASIA-PACIFIC PERSPECTIVES U ntil now, treatment options for keratoconus have focused on the halt of progression and delay of corneal transplantation. This autologous adult stem cell treatment is quite an innovative attempt to restore the corneal stroma with evidence of keratocyte proliferation and new collagen production in advanced keratoconus. The study of 14 patients by Dr. Alio demonstrated good results in terms of visual acuity and corneal thickness without any complications. Of interest, only the injections of adult stem cells in the stromal pocket resulted in immediate and significant improvement of uncorrected visual acuity during the first month, showing the maintenance of visual acuity and corneal transparency throughout the first year. Although insertion of the decellularized corneal stroma lamina with stem cells increased corneal thickness significantly, early onset of corneal haziness and edema might draw relatively fair results in visual acuity over the first year. Further studies for a larger number of cases are definitely needed for proper statistical analysis. However, I believe that adult stem cell injection treatments might be also effective in moderate keratoconus and provide improvement of visual acuity. Editors’ note: Prof. Chung is a consultant for Hoya Medical. by Rich Daly Contributing Writer Contact information Nattis: asn516lu@gmail.com Karamichos: Dimitrios.Karamichos@unthsc.edu This article originally appeared in the May 2020 issue of EyeWorld . It has been slightly modified and appears here with permission from the ASCRS Ophthalmic Services Corp. Adult stem cells treat advanced keratoconus R esearch has found adult stem cells to be “moderately effective” in treating advanced keratoconus. A prospective, interventional, nonrandomized series showed that intrastromal implantation of autologous adipose-derived adult stem cells (ADASC), with or without sheets of decellularized donor human corneal stroma, was moderately effective for the treatment of advanced keratoconus and did not result in complications at 1 year of follow up. The study 1 included 14 consecutive patients who were divided into those that received implantation of autologous ADASC alone, decellularized donor 120-μm thick corneal stroma lamina alone, and recellularized donor lamina with autologous ADASC with another layer of cells at the time of the surgery. The ADASC were obtained by elective liposuction. Implantation was performed in the corneal stroma through a femtosecond laser-assisted 9.5- mm diameter lamellar dissection under topical anesthesia. In addition to the lack of complications, there were no lines of visual acuity lost among the participants. Corrected distance visual acuity improved by 0.231, 0.264, and 0.094 Snellen lines, respectively. In the latter two groups, sphere improved by 2.35 D and 0.625 D, respectively. Corneal thickness improved by a mean of 14.5 μm in the first group and 116.4 μm in the latter two groups. New collagen production was observed at the surgical plane in the first group. The results are preliminary, and larger follow-up studies are needed to further analyze the safety and efficacy of this technique as well as long-term results. “Although techniques such as crosslinking and corneal transplantation are good for treatment of keratoconus, to have [other] techniques available, which may be able to help patients who do not qualify for crosslinking or transplantation, can add to our ‘tool box’ as a way of treating our patients,” said Alanna Nattis, DO, adding that more data is needed to ensure corneas remain stable over several years, without any evidence of rejection, late scarring, haze, or increased ectasia. Dimitrios Karamichos, PhD, who studies corneal surgery, said the results were “significant” and “different” but warned that the results were not compared to available crosslinking options. “We need a treatment, but those patients need the option of the cornea transplant once they get to this stage, so what continued on page 42