Genipin-Crosslinked Donor Sclera for Posterior Scleral Contraction/Reinforcement to Fight Progressive Myopia

Abstract

PURPOSE. Myopia has become a global public health problem, particularly in East Asia where myopic retinopathy has become one of the leading causes of blindness and visual impairment in the elderly population. The purpose of this study was to evaluate the efficacy of posterior scleral contraction/reinforcement (PSCR) surgery on controlling the progressive elongation of axial length of highly myopic eyes in young patients.METHODS. This is a prospective self-controlled interventional case series. Forty young patients (<18-years old) with progressive high myopia received PSCR with a genipin-crosslinked donor scleral strip for one eye and the fellow eye served as concurrent control without surgery. The main outcome measurement was the change of axial length over 2 to 3 years of follow-up. RESULTS.Immediately after the surgery, axial length was shortened and subsequently increased by 0.32 mm over the follow-up period. In contrast, axial length of the fellow eyes increased by 0.82 mm over the same period (P < 0.001, paired t-test). PSCR delayed axial elongation in eyes with or without staphyloma. No significant change of visual acuity, cornea refractive power, or retina thickness was noted between the surgery and fellow eyes. None of the patients lost visual acuity compared with the baseline. The procedure was well tolerated with only temporary corneal refractive axis shifts that recovered by the 6-month postsurgical visit.CONCLUSIONS. PSCR with genipin-crosslinked sclera is safe and effective to restrain eye globe elongation in young patients within a 2-to 3-year follow-up period.

International survey of contact lens fitting for myopia control in children

“…Overall, MC represented only 2.3% of all contact lens fits, notwithstanding the gradual increase in MC fitting throughout the survey period. Three factors that may have limited the uptake of contact lenses for MC are (1) the lack of on-label MC products for most of the survey period and in most parts of the world; (2) reservations and uncertainty as to the true efficacy of MC fitting [15], and (3) an apparent lack of awareness among parents of myopic children of the ocular health risks of myopia development and the potential benefits of MC [16]. Nevertheless, the gradual increase in MC fitting over the course of this survey possibly reflects a growing awareness among eye care practitioners of the importance of arresting myopia progression where possible [17].…”

“…There are four fundamental approaches to MCsurgical, pharmacological, behavioural, and optical. Surgical approaches have focused on posterior scleral cross-linking and appear to be applied to high levels of myopia [1][2][3]. Pharmacological approaches have centered around the use of the anti-muscarinic agents atropine [4] and pirenzepine [5]; these drugs have been demonstrated to partially arrest the progression of myopia in children, although the precise mechanism by which this occurs is unclear.…”

Understanding Myopia: Pathogenesis and Mechanisms

“…Scleral thinning may alter the tissue strength surrounding the optic nerve head, rendering myopic eyes more susceptible to glaucomatous damage [94,95]. Consequently, posterior reinforcement surgery using donor scleral tissue has been refined over the years to arrest further axial elongation and scleral thinning in highly myopic eyes [96,97]. Although anterior scleral thickness is similar between myopic and non-myopic eyes [98][99][100], there is growing evidence that the anterior sclera thins slightly during accommodation, particularly in myopic eyes [101,102], most likely due to biomechanical forces of the ciliary muscle.…”

Ethnopharmacology of Fruit Plants: A Literature Review on the Toxicological, Phytochemical, Cultural Aspects, and a Mechanistic Approach to the Pharmacological Effects of Four Widely Used Species

“…Through a mechanism still unknown, genipin ( 55 ) induces CXL by up to 7%, a result superior to that induced by treatment with riboflavin and UV light applied in the control group, which presented only 5.6% cross-linking. To achieve 7% cross-linking, 140 μL of 0.5% genipin ( 55 ) was administered every 1 h for 2 h [ 168 ]. The role of genipin ( 55 ) investigated in cattle suggests further studies in humans.…”

“…The sclera is a layer of fibrous, opaque and dense tissue that lines the eye, on which the cross-linking capacity of genipin was tested ( 55 ), which doubled the sclera resistance and increased by 30 % resistance to enzymatic degradation, which could promote sclera weakening. The study points out the efficacy and safety of PSCR with sclera cross-linked with genipin ( 55 ) to restrict axial elongation of the eyeball [ 168 ].…”