Dr Ka Wai KAM; Prof Alvin L. YOUNG
Department of Ophthalmology & Visual Sciences, The Chinese University of Hong Kong
Prince of Wales Hospital & Alice Ho Miu Ling Nethersole Hospital
Do you know that the first corneal transplantation in Hong Kong was performed just over 60 years ago?[1] The surgery for sight restoration, being the most performed of all transplantation operations, was first accomplished in 1961 at Tung Wah Eastern Hospital, led by a group of expatriate surgeons. These ophthalmologists brought fresh corneae from overseas Eye Banks due to the lack of local facilities of the time. This momentous occasion led to the inception of the Hong Kong Eye Bank in 1962 subsequently. As the general public began to appreciate the potential benefits of a corneal transplantation and the prospect of restored vision, the procedure quickly gained attention and became sought-after by patients who suffered from corneal blindness living in darkness. However, during the early years, local donors were rare and Hong Kong had to rely on Sri Lanka for imported grafts in order to meet the soaring demands. Over the last few decades, with the combined effort from ophthalmologists, vision scientists, dedicated staff of the eye bank and support from the government, not only was there a steady rise in the number of local donors, but also a marked improvement in the quality of the locally harvested corneal grafts. Nevertheless, the demand for cornea continued to exceed the number of grafts available per year and on average, patients in Hong Kong as of 2022 still have to wait for about a year or more for a corneal graft.
In Hong Kong, the majority of corneal transplantations are performed with the aim to improve vision. Occasionally, a corneal graft may be required for repairing a badly damaged eye due to traumatic injury, fulminant infections or severe & or recurrent inflammation. While full-thickness corneal transplantations are still being performed in a similar way to how the original surgery was developed more than a century ago, surgeons have now acquired the skills to selectively replace a diseased corneal layer with the help of better microsurgical instruments, techniques and wetlab training. In recent years, the Hospital Authority Eye Bank has been providing even thinner corneal grafts (Descemet’s Stripping Automated Endothelial Keratoplasty [DSAEK] and Descemet Membrane Endothelial Keratoplasty [DMEK]) allowing for better visual outcomes and faster recovery over a conventional full-thickness corneal transplantation. These grafts are suitable for patients who have impaired function of the most posterior layer of the cornea – either from inherited conditions, secondary to infections, injury or previous intraocular surgery.[2] Nowadays, these lamellar grafts can be prepared at the Eye Bank and delivered to the surgeon on the day of transplantation. This shortens the overall surgical time in theatre, and also reduces the risk of inadvertent graft damage & wastage during manual dissection by greener less experienced surgeons.
The Eye Bank also provides tissues for artificial cornea (keratoprosthesis) and limbal stem cell transplantations, which further expands the number of potential beneficiaries who require something more than a conventional corneal transplantation.[3,4] Indeed, we are living in an exciting era as corneal surgeons and we are most thankful to the support for corneal donors over the last sixty years in Hong Kong. Your support to the cause of organ donation would continue to help us in this battle against corneal blindness and other life-threatening conditions needing solid organ transplantations. Hopefully, more patients would then have a second chance to live a full life and see our world again.
References
1. Kam KW, Wong VWY, Chow VWS, Yiu EPF, Young AL. Celebrating 60 years of corneal transplant in Hong Kong. Hong Kong Med J 2021 Dec;27(6):458-60. https://www.hkmj.org/abstracts/v27n6/458.htm
2. Young AL. 眼角膜後層移植可減低排斥 助患者重見光明. On.cc 2021. https://hk.on.cc/hk/bkn/cnt/news/20211014/bkn-20211014025142346-1014_00822_001.html
3. Kam KW, Young AL. 淺談簡易角膜緣表皮移植. Hong Kong Economic Journal 2022. https://www1.hkej.com/dailynews/culture/article/3031394
4. Kam KW, Young AL. 人工角膜──角膜失明現曙光. Hong Kong Economic Journal 2020. https://www1.hkej.com/dailynews/culture/article/2357492
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