Scleral Reinforcement Research Articles

Efficacy of Posterior Scleral Reinforcement in Treating Anisometropic Amblyopia Associated With Unilateral High Myopia in Children.

The aim of this study is to examine the effectiveness and safety of posterior scleral reinforcement (PSR) for treating anisometropic amblyopia and myopia associated with high myopia in children. Children with unilateral high myopia (uHM) and anisometropic amblyopia who underwent PSR in their highly myopic eyes were included in this study. The treated eye was designated as the PSR group, whereas the healthier eye served as the control, and paired comparisons were made. Thirteen patients (13 eyes in each group) were included, with an average age of 5.85±2.08 years. Cross-sectional comparisons between the groups showed that within 2 to 3 years after surgery, the PSR group had a significantly greater increase in best-corrected visual acuity per month compared with the control group (P=0.03), a significantly lower increase in axial length per month (P=0.007), and a significantly smaller absolute value of the increase in SE per month (P=0.002). Temporal longitudinal comparisons within the PSR group indicated that the increase in axial length per month 2 to 3 years after surgery was significantly slower than 1 year before surgery (P=0.045). The increase in best-corrected visual acuity per month was higher than 1 year before surgery, although not significantly (P=0.859). PSR is a safe and effective treatment for refractory anisometropic amblyopia caused by uHM, and for controlling axial length and the degree of myopia.

Posterior scleral reinforcement surgery effectively slows the rate of high myopic progression in children

To investigate the rate of axial length elongation and high myopia progression in operated eyes before and after posterior scleral reinforcement (PSR) surgery. This was a retrospective study. Children with pathological myopia treated with PSR at Beijing Tongren Hospital between May 2013 and May 2020 were recruited into the PSR surgery group. Children matched for age and myopia were recruited into the control group. All children underwent comprehensive ophthalmologic examinations. The presurgical and postsurgical rates of axial length elongation and myopic (spherical equivalent) progression were calculated. A total of 35 PSR patients were included in the study. The mean age was 6.5±3.0years (range 2 to 14years). Mean follow-up was 544days (range 216 to 1657days). The rate of axial length elongation was significantly less after posterior scleral reinforcement surgery (0.505±0.048mm per year prior to surgery; 0.382±0.045mm per year after surgery, P<0.001). The rate of myopic progression decreased after posterior scleral reinforcement surgery (1.162±0.118D per year prior to surgery; 0.153±0.437D per year after surgery, P=0.0239). There was no statistically significant difference in axial length elongation or myopic progression between pre-inclusion and post-inclusion in the control group. Moreover, the children's best-corrected visual acuity was significantly improved after posterior scleral reinforcement surgery (P<0.001). Posterior scleral reinforcement surgery effectively decreased the rate of high myopic progression and axial length elongation in children.

The feasibility and safety of biomaterials for posterior scleral reinforcement in rabbits

To explore the feasibility and safety of biomaterials for posterior scleral reinforcement (PSR) in rabbits. Decellularization and genipin crosslink were applied to the fresh bovine pericardium and porcine endocranium, and then mechanical properties, suture retention strength, and stability were tested. PSR operation was performed on 24 rabbit eyes using treated biological materials. Ophthalmic examination was performed regularly before and after PSR operation (1 week, 1 month, 3 months, 6 months). To evaluate the effectiveness, A ultrasound, diopter, and optical coherence tomography were conducted. General condition, fundus photograph, and pathological examination were recorded to evaluate the safety. Compared with genipin crosslinked bovine pericardium (Gen-BP) (21.29 ± 13.29 Mpa), genipin crosslinked porcine endocranium (Gen-PE) (34.85 ± 3.67 Mpa,P< 0.01) showed a closer elastic modulus to that of genipin crosslinked human sclera. There were no complications or toxic reactions directly related to the materials. Capillary hyperplasia, inflammatory cell infiltration, and collagen fiber deposition were observed, and the content of type I collagen fibers increased after PSR. Overall, the choroidal thickness of treated eyes was significantly thickened at different time points after PSR, which were 96.84 ± 21.08 μm, 96.72 ± 22.00 μm, 90.90 ± 16.57 μm, 97.28 ± 14.74 μm, respectively. The Gen-PE group showed changes that were almost consistent with the overall data. Gen-BP and Gen-PE are safe biological materials for PSR. The Gen-PE group demonstrated more significant advantages over the Gen-BP group in terms of material properties.

Surgical Outcomes, Ocular Safety and Tolerability of Bio-Interventional Cyclodialysis with Allograft Scleral Reinforcement: Clinical Experience of More than 240 Cases.

Background: To report the surgical safety of reinforced bio-interventional cyclodialysis with scleral allograft reinforcement. Methods: This was a consecutive case series of 243 eyes with open-angle glaucoma who underwent a bio-scaffolded cyclodialysis (BSC) procedure for uveoscleral outflow enhancement using allogeneic bio-spacers to maintain patency of the internal filtration conduit. Results: 79% of the eyes underwent concomitant phacoemulsification cataract surgery prior to BSC intervention, while the remaining eyes underwent stand-alone BSC surgery. All patients had a postoperative surgical safety period of at least 30 days. There were no sight-threatening or serious ocular adverse events. There was one case of prolonged iritis beyond 30 days, which resolved with topical treatment. Two cases (0.8%) of intraoperative and five (2%) of postoperative non-sight-threatening hyphema were without clinical sequelae, which resolved with conservative management. There were 11 cases of IOP elevation and one case of numeric hypotony without maculopathy, which resolved within the study period. The rate of secondary surgical intervention for IOP control was low, and overall, IOP for the cohort improved in the postoperative period, with 78.6% of eyes achieving IOP ≤ 18 mmHg without an increase in medications. Conclusions: Allogeneic biotissue for cyclodialysis intervention demonstrates a biocompatible ocular profile as an implantable material for internal scleral reinforcement during uveoscleral outflow enhancement surgery.

Advancements in Myopic Macular Foveoschisis Research.

Presently, the global prevalence of myopia and high myopia reaches approximately 1.95 billion and 277 million individuals, respectively. Projections suggest that by 2050, the number of people with myopia may rise to 4.758 billion and those with high myopia to 938 million. In highly myopic eyes, the occurrence of MF is reported to be as high as 8-33%. This review comprehensively addresses the classification, pathogenesis, natural progression, concomitant pathologies, and therapeutic strategies for macular foveoschisis in highly myopic patients. In recent years, macular foveoschisis has emerged as a prevalent complication in individuals with high myopia, primarily resulting from the combination of inward traction by vitreoretinal adhesions and outward traction exerted by posterior scleral staphyloma on the retina. While some maintain partial visual stability over an extended period, others may progress to macular holes or even retinal detachment. For highly myopic patients with macular foveoschisis, the mainstay procedures are vitrectomy, macular buckle, and posterior scleral reinforcement. However, there is controversy about whether to perform inner limiting membrane peeling and gas filling.

Clinical outcomes of posterior scleral reinforcement in Chinese high myopia children

We aim to observe the posterior scleral reinforcement (PSR) clinical outcomes of children with high myopia and analyze the retinal vessel alteration before and after PSR by using angiography optical coherence tomography (angio-OCT). Fifty-six pediatric participants (112 eyes) clinically diagnosed high myopia were recruited and were treated by PSR in Shanghai Children’s Hospital from June 1, 2021 to May 1, 2023. The average age ranged from 5.42 to 14.83 years (mean 8.83 years) and mean follow up duration was 8.7 months (3–24 months). The axial length (AL) was significantly shortened after PSR (p < 0.05). The spherical equivalent (SE) and the best-corrected visual acuity (BCVA) were also improved without severe rejection in the follow-up. Compared with baseline, angio-OCT parafoveal vessel indices including vascular area density (VAD) and vascular skeleton density (VSD) on the superficial capillary plexus layer (SCPL), as well as VAD and vessel perimeter index (VPI) on the deep capillary plexus layer (DCPL), were significantly increased after PSR surgery (p < 0.05). VPI on the SCPL, vascular diameter index (VDI) and VSD on the DCPL were also improved without statistical difference after PSR. The VSD on SCPL, VAD on DCPL of the right eyes and the VPI on SCPL of the left eyes were significantly increased after PSR (p < 0.05). PSR surgery can shorten the AL and can stable BCVA and SE in high myopia children. The angio-OCT parameters indicated that the retinal microcirculation supply was significantly improved after PSR.

The Evolving Surgical Paradigm of Scleral Allograft Bio-Tissue Use in Ophthalmic Surgery: Techniques and Clinical Indications for Ab-Externo and Ab-Interno Scleral Reinforcement.

To review the latest surgical advances and evolving clinical use of scleral bio-tissue for reinforcement in the eye and review the published literature on novel surgical applications of scleral allograft bio-tissue. Conventional surgical procedures for scleral reinforcement using homologous scleral allograft have been traditionally ab-externo interventions comprising of anterior or posterior reinforcement of the sclera for clinical indications such as trauma, scleromalacia, glaucoma drainage device coverage, scleral perforation, buckle repair as well as posterior reinforcement for pathologic myopia and staphyloma. There have been a few novel ab-interno uses of scleral bio-tissue for reinforcement in both retina and glaucoma. Over the last decade, there has been an increase in peer-reviewed publications on scleral reinforcement, reflecting more interest in its clinical applications. With favorable biological and biomechanical properties, scleral allograft may be an ideal substrate for an array of new applications and surgical uses.

Long-term outcomes of anti-vascular endothelial growth factor therapy with and without posterior scleral reinforcement on myopic maculopathy in myopic choroidal neovascularization eyes

BackgroundAnti-vascular endothelial growth factor (anti-VEGF) therapy is used for myopic choroidal neovascularization (mCNV). Patchy chorioretinal atrophy (pCRA) enlargement has been reported in mCNV cases associated with vision loss. Our aim was to compare the long-term effectiveness of anti-VEGF therapy alone versus anti-VEGF followed by posterior scleral reinforcement (PSR) in controlling myopic maculopathy in mCNV eyes.MethodsWe performed a retrospective review of the medical records of 95 high myopia patients (refractive error ≥ 6.00 diopters, axial length ≥ 26.0 mm) with mCNV. Patients were treated with anti-VEGF alone (group A) or anti-VEGF followed by PSR (group B). The following data were collected: refractive error, best corrected visual acuity (BCVA), ophthalmic fundus examination, ocular coherence tomography and ocular biometry at 12 and 24 months pre- and postoperatively. The primary outcomes were changes in pCRA and BCVA.ResultsIn 26 eyes of 24 patients, the mean pCRA size significantly increased from baseline (0.88 ± 1.69 mm2) to 12 months (1.57 ± 2.32 mm2, t = 3.249, P = 0.003) and 24 months (2.17 ± 2.79 mm2, t = 3.965, P = 0.001) postoperatively. The increase in perilesional pCRA in group B (n = 12) was 98.2% and 94.2% smaller than that in group A (n = 14) at 12 and 24 months (Beta 0.57 [95% CI 0.01, 191 1.13], P = 0.048). In group B, 7 eyes (58.3%) gained more than 2 lines of BCVA compared with only 4 eyes (28.6%) in group A at 24 months.ConclusionAnti-VEGF therapy followed by PSR achieved better outcomes than anti-VEGF therapy alone in controlling the development of myopic maculopathy in mCNV and may constitute a better treatment option by securing a better long-term VA outcome.

Effect and safety posterior scleral reinforcement on controlling myopia in children: a meta-analysis

PurposeThe aim of this meta-analysis was to assess the efficacy of posterior scleral reinforcement (PSR) on the control of pediatric myopia. Electronic databases were systematically searched.MethodsStandardized mean differences (SMDs) of outcomes were calculated. Eight studies with 357 patients with pediatric myopia were included. The SMD for the increase in mean axial length (AL) in the PSR and control group was − 1.19 (95% CI − 1.71, − 0.68). ResultsThe SMD for decrease of best-corrected visual acuity (BCVA) LogMAR in the PSR and control group was 0.85 (95% CI 0.28, 1.43). The SMD for change in intraocular pressure (IOP) at the time of surgery and at the end of the follow-up period in the PSR group was − 0.01 (95% CI − 0.48, 0.47).ConclusionThis meta-analysis indicates that PSR surgery may be an effective therapeutic strategy to control the progression of myopia in childhood with acceptable adverse effects.

Gradient myopic defocus causes scleral tissue reinforcement and structural scleral remodelling

Aims/Purpose: To determine histological effects of lens induced refractive change on scleral remodelling in chicks.Methods: 18 Ross‐Ross chicks were raised for 14 days on a 14 hr light/10 hr dark cycle. 6 chicks were allowed to develop normally. 6 chicks wore conventional ‐10D lenses for the full 14 days. 6 chicks wore conventional ‐10D lenses for the first 7 days and myopia progression control (MPC) lenses or the next 7 days. MPC lenses had a central power of ‐10D and a gradient power rise at pupil edge (+ 2.75D). Birds were euthanized after 14 days and eyes were routinely processed for histopathological evaluation. Whole mount H&amp;E‐stained tissue sections were microscopically analysed using bright field microscopy.Results: All lens treated birds developed significant myopia as expected Total scleral thickness was significantly reduced in the group wearing conventional ‐10 lenses (p &lt; 0.05), but remained comparable to the normal control group for the MPC lenses treated birds. New appositional growth of the cartilaginous sclera was observed in all MPC lenses treated eyes and only in those eyes. The thickness of the cartilaginous component of the sclera was 135 ± 6, 153 ± 5, 125 ± 8 μm for conventional myopic, MPC lenses treated, and control birds respectively. There was a significant increase in the cartilaginous scleral thickness in the MPC lenses treated birds compared to the other two groups (p &lt; 0.03), but not between the conventional ‐10D lens treated and control birds (p &gt; 0.05).Conclusions: It is possible to induce appositional growth in hyaline cartilage in the chick sclera. In our study, this has only been achieved by using MPC lenses to reverse previously induced experimental myopia with conventional minus lenses. Our finding suggests that gradient decrease in peripheral lens power and the resulting differential level of defocus it causes could be a potential trigger of scleral reinforcement through stimulation of cartilage growth in the chick sclera.

Analysis of morphological and quantitative changes in pathological myopia and perioperative changes in posterior scleral reinforcement using three-dimensional magnet resonance imaging.

Objective: To compare the morphological and quantitative changes in pathological myopia (PM) and the perioperative changes in posterior scleral reinforcement (PSR) using three-dimensional magnetic resonance images (3D MRI). Methods: A total of 49 patients with high myopia (HM; 98 eyes), 15 with pathological myopia (PM; 19 eyes), and 10 without high myopia (NORM; 20 eyes) were recruited between September 2019 and July 2021. The patients underwent measurements of refractive error and axial length, as well as 3D MRI of the eyeball. Python was used to analyze the 3D MRI images, calculate the vitreous volume, establish a topography of the height of the eyeball posterior surface, and calculate the rate of change in height (H). For the PM group undergoing PSR, changes in vitreous volume and the highest point of the eyeball posterior surface in four quadrants (temporal, subtemporal, nasal, and subnasal) were compared before and after PSR. Results: The vitreous volume was smaller in the NORM group compared to the HM and PM groups (p < 0.01). The PM group had a larger volume than the HM group (p < 0.01). The H for the PM group was higher than that of the NORM and HM groups (p < 0.01). After PSR in the PM group, the total vitreous volume, as well as the volume in the subnasal and supratemporal quadrants, decreased (p < 0.05). Additionally, the highest point of the eyeball's posterior surface was generally shifted to the upper nasal side. Finally, the shape and position of the scleral band after PSR were plotted. Conclusion: 3D MRI is capable of a quantitative description of the eyeball morphology in PM and PSR. It allows for precise calculations of changes in vitreous volume and the H of the posterior surface. It also facilitates a meticulous analysis of the specific details of the scleral band following PSR.

Observation of the effect of posterior scleral reinforcement combined with orthokeratology and 0.01% atropine in the treatment of congenital myopia: a case report

BackgroundMyopia has recently emerged as a significant threat to global public health. The high and pathological myopia in children and adolescents could result in irreversible damage to eye tissues and severe impairment of visual function without timely control. Posterior scleral reinforcement (PSR) can effectively control the progression of high myopia by limiting posterior scleral expansion, improving retrobulbar vascular perfusion, thereby stabilizing the axial length and refraction of the eye. Moreover, orthokeratology and low concentrations of atropine are also effective in slowing myopia progression.Case presentationA female child was diagnosed with binocular congenital myopia and amblyopia at the age of 3 and the patient’s vision had never been rectified with spectacles at the first consultation. The patient’s ophthalmological findings suggested, high refractive error with low best corrected visual acuity, longer axial length beyond the standard level of her age, and fundus examination suggesting posterior scleral staphyloma with weakened hemodynamics of the posterior ciliary artery. Thereby, PSR was performed to improve fundus health and the combination of orthokeratology and 0.01% atropine were performed to control the development of myopia. Following up to 8 years of clinical treatment and observations, the progression of myopia could be well controlled and fundus health was stable.ConclusionIn this report, 8-year of clinical observation indicated that PSR could improve choroidal thickness and hemodynamic parameters of the retrobulbar vessels, postoperative orthokeratology combined with 0.01% atropine treatment strategy may be a good choice for myopia control effectively.

Evaluation of new robust silk fibroin hydrogels for posterior scleral reinforcement in rabbits.

Background: Currently, there is no ideal material available for posterior scleral reinforcement (PSR) to prevent the progression of high myopia. In this study, we investigated robust regenerated silk fibroin (RSF) hydrogels as potential grafts for PSR in animal experiments to evaluate their safety and biological reactions. Methods: PSR surgery was performed on the right eye of twenty-eight adult New Zealand white rabbits, with the left eye serving as a self-control. Ten rabbits were observed for 3 months, while 18 rabbits were observed for 6 months. The rabbits were evaluated using intraocular pressure (IOP), anterior segment and fundus photography, A- and B-ultrasound, optical coherence tomography (OCT), histology, and biomechanical tests. Results: No complications such as significant IOP fluctuation, anterior chamber inflammation, vitreous opacity, retinal lesion, infection, or material exposure were observed. Furthermore, no evidence of pathological changes in the optic nerve and retina, or structural abnormalities on OCT, were found. The RSF grafts were appropriately located at the posterior sclera and enclosed in fibrous capsules. The scleral thickness and collagen fiber content of the treated eyes increased after surgery. The ultimate stress of the reinforced sclera increased by 30.7%, and the elastic modulus increased by 33.0% compared to those of the control eyes at 6months after surgery. Conclusion: Robust RSF hydrogels exhibited good biocompatibility and promoted the formation of fibrous capsules at the posterior sclera in vivo. The biomechanical properties of the reinforced sclera were strengthened. These findings suggest that RSF hydrogel is a potential material for PSR.

A case report: Marfan syndrome with X trisomy and FBN1 and SDHB mutations

BackgroundMarfan syndrome (MFS) is a rare autosomal dominant connective tissue disorder affecting the cardiovascular, skeletal, and ophthalmic systems. This report aimed to describe a novel genetic background and treatment prognosis of MFS.Case presentationA proband was initially diagnosed with bilateral pathologic myopia and suspected MFS. We performed whole exome sequencing and found a pathogenic nonsense FBN1 mutation in the proband, which confirmed the diagnosis of MFS. Notably, we identified a second pathogenic nonsense mutation in SDHB, which increased the risk of tumours. In addition, the proband karyotype was X trisomy, which may cause X trisomy syndrome. At the 6-month follow-up after posterior scleral reinforcement surgery, the proband's visual acuity improved significantly; however, myopia was still progressing.ConclusionsWe report a rare case of MFS with a X trisomy genotype, a mutation in FBN1 and a mutation in SDHB for the first time, and our findings could be helpful for the clinical diagnosis and treatment of this disease.

Clinical Feasibility and Safety of Scleral Collagen Cross-Linking by Riboflavin and UltravioletA in Pathological Myopia Blindness: A Pilot Study.

To investigate the feasibility and safety of scleral ultravioletA (UVA) cross-linking (scleral CXL) on pathologically blindness. This was a prospective, observational clinical study. Five patients with monocular blindness due to pathological myopic maculopathy were enrolled. Eyes with best corrected visual acuity (BCVA) under 0.05 were defined as experimental eyes. The fellow eyes were defined as control eyes. Patients first underwent posterior scleral reinforcement (PSR) surgery in the control eye. Thereafter, scleral CXL surgery was performed in the experimental eye on the same day. Visual acuity, BCVA, slit lamp biomicroscopic examination, intraocular pressure measurement, corneal specula microscopies, axis length measurement, funduscopy with pupil dilation, color fundus photography, full-field flash electroretinography, optical coherence tomography, and color Doppler flow imaging were performed at baseline, 1week, 1month, 3months, 6months, and 12months after surgery. No signs of inflammation were observed after operation and throughout the follow-up period. Retinoschisis was improved, while choroidal neovascularization fibrosis and retinal and choroidal atrophy were unchanged after scleral CXL. There were no statistically significant differences in the ophthalmic artery, central retinal artery, and posterior ciliary artery parameters of color Doppler flow imaging or in retinal thickness, within experimental and control eyes, at baseline, 1week, 1month, 3months, or 12months (P > 0.05). This pilot study verified the feasibility and safety of scleral CXL on human blindness. The UVA-CXL on the sclera of human eyes seems to have the same effect as PSR in preventing progressive pathological myopia in the future. Chinese Clinical Trial Registry (ChiCTR2100042422).

Posterior scleral reinforcement for the treatment of myopic traction maculopathy

BackgroundThis study aimed to investigate the clinical effectiveness of posterior scleral reinforcement(PSR) for the treatment of myopic traction maculopathy (MTM).MethodsThis was a prospective study of 32 eyes from 20 patients with MTM treated with PSR using genipin-cross-linked donor sclera. The length of the scleral strip used for the surgery was designed to be 1.5-times the axial length of the eye, whereas its width was 0.4-times the axial length of the eye. The optical coherence tomography images, spherical equivalent of refractive error, axial length, best corrected visual acuity, electroretinogram findings, and intraocular pressure of the patients were assessed postoperatively.ResultsThe mean duration of follow-up was 17.80 ± 8.74 months. The differences between the spherical equivalent of refractive error, best corrected visual acuity, axial length, and electroretinogram findings recorded preoperatively and those measured postoperatively were statistically significant (p < 0.05). The final reduction in axial length was 1.64 ± 0.85 mm. At the end of the follow-up, optical coherence tomography showed essential foveal reattachment in 30 eyes (93.75%), partial reattachment in two eyes (6.25%), and closure of macular holes in seven eyes (77.78%). No retinal detachment, vitreous haemorrhage, or other serious complications occurred following the surgery.ConclusionsPosterior scleral reinforcement with genipin-cross-linked sclera showed safe and effective outcomes for the treatment of MTM during a follow-up period of at least one year.Trial registration11\\12\\2018, ChiCTR1800020012.

Long-term outcome of pathologic myopic foveoschisis treated with posterior scleral reinforcement followed by vitrectomy.

To report the long-term outcome of posterior scleral reinforcement (PSR) followed by vitrectomy for pathologic myopic foveoschisis (MF). The records of 27 patients (44 eyes) treated with posterior scleral reinforcement (PSR) followed by vitrectomy for pathologic MF were retrospectively reviewed. The best-corrected visual acuity (BCVA), refractive error, axial length, and spectral-domain optical coherence tomography findings and complications were analyzed. Forty-four eyes of 27 patients were included in this study. The follow-up period was 47.98±18.23mo (24-83mo). The mean preoperative BCVA (logMAR) was 1.13±0.63, and the mean postoperative BCVA was 0.30±0.33 at the last visit. There showed a significant improvement in BCVA postoperatively (P<0.001). Postoperative BCVA in 41 eyes (93%) was improved compared with the preoperative one. Forty-two eyes (95.45%) got total resolution of the MF after surgery. The remaining two eyes (4.55%) got partial resolution of foveoschisis. The preoperative foveal thickness was 610.45±217.11 µm and the postoperative foveal thickness at the last visit was significantly reduced to 177.64±55.40 µm (P<0.001). The preoperative axial length was 29.60±1.71 mm, and the postoperative axial length was 29.74±1.81 mm at the last visit. There was no significant increase in axial length within 47.98±18.23mo of follow-up (P=0.562). There was no recurrence of foveoschisis or occurrence of full-thickness macular hole during the whole follow-up period. For pathologic MF, PSR followed by vitrectomy is an effective procedure to improve the visual acuity and the anatomical structure of macula. It can also stabilize the axial length for a long time.

Efficacy of Posterior Scleral Reinforcement in Children with High Myopia: A Systematic Review and Meta-Analysis

Purpose: The purpose of this meta-analysis is to evaluate the effect of posterior scleral reinforcement (PSR) on axial length (AL), spherical equivalents (SE) and best corrected visual acuity (BCVA) in children with high myopia. Methods: The databases PubMed, EMBASE, Wanfang Database, CNKI, CSTJ and Cochrane Library from inception to March 2021 were searched to identify the relevant studies which evaluated the efficacy of PSR for patients under 18 years old with high myopia. The main parameters include AL, SE and BCVA. Revman software version 5.3 was used to perform the statistical analyses. Results in proportion with 95% confidence interval were calculated using dersimonian-laird model. Results: 8 studies including 383 PSR treated and 281 control eyes were finally included. Our analysis indicated that PSR could slow down the increase of AL and the loss of vision loss (P&lt;.01). However, in the subgroup with a follow-up period shorter than three years, there was no statistical difference in BCVA changes between the PSR and control groups (WMD=-0.02, 95%CI -0.07 to 0.04, P=.58, I2=0%). The BCVA changes is significant after 3 years follow up (WMD=-0.13, 95%Cl -0.21 to -0.05, P=0.007). Conclusion: PSR can benefit children in controlling the growth of AL, SE and decrease of visual acuity. 3 years after PSR may be a critical time point. Given the limitations in our study, more research with larger sample sizes and more accurate data are required to reach a firmer conclusion.

Biomechanical Considerations of Patching Material for Posterior Scleral Reinforcement Surgery.

PurposeTo characterize biomechanical properties of genipin-crosslinked human dura mater as reinforcing material for posterior scleral reinforcement (PSR) and to compare it with crosslinked human sclera.MethodsDonor dura mater and sclera were crosslinked in the same optimized genipin solution. Resistance to enzyme degradation for both materials were investigated by exposing the materials to accelerated enzyme degrading. Elastic modulus and tensile strength were measured by biomechanics testing equipment. Crosslinked human dura mater was used as reinforcing patch in PSR on 57 adult pathologic myopic eyes. The patients were followed up for an average 3 years. The main outcome was eye globe axial length change and safety profile of the reinforcing material.ResultsCrosslinked dura mater demonstrated similar percentage weight loss to crosslinked sclera when exposed to enzymatic solution. Dura mater has higher density than sclera. The retaining elastic modulus after enzyme exposure was 72.02 MPa for crosslinked dura mater while 53.88 MPa for crosslinked sclera, 34% greater for crosslinked dura mater, P = 0.0186). At the end of 3 years follow-up, the mean globe axis of the surgery eyes was reduced by 1.29 mm (from 30.81 to 29.51 mm, P < 0.0001, paired t-test). Visual acuity (BCVA logMar) improved by 0.10 logMar unit which is an improvement of five letters (P = 0.0184, paired t-test). No material specific complication was noted.ConclusionCrosslinked human dura mater may be superior to crosslinked human sclera as reinforcing material for PSR to manage progression of high myopia. This material was well tolerated on human eye.

Myopia: Pathogenesis and Actual Methods of Control. Literature Review

This literature review analyzed of current information about prevalence, pathogenesis and methods of controlling the progression of myopia. Bibliographic research of scientific publications was carried out in the following databases: Medline, Pubmed, Cochrane, eLibrary. Languages of publications: Russian and English. Analysis of Russian and foreign literature has demonstrated that the prevalence of myopia is increasing extensively worldwide. All the main methods of controlling myopia are divided into measures aimed at changing the child’s lifestyle, drug therapy, optical correction and surgical methods. The most debatable issue remains the surgical methods of controlling myopia, in particular, posterior scleral reinforcement and UV-A-crosslinking of the sclera.