Vincenz Fukala (1847–1911) and the early history of clear-lens operations in high myopia

Vincenz (Wincenty) Fukala, was born in 1847 in Zolkiew at Galicia in Poland, studied medicine and ophthalmology in Vienna in 1871. He was a pioneer in systematically extracting the clear crystalline lens in young patients with high myopia. He demonstrated the benefit to this group of increased visual acuity which enabled them to work and ophthalmologists gradually began to carry out surgery in high myopes worldwide. He persisted in operating despite the vigorous opposition of several authorities but, through sheer determination he convinced skeptics of the efficacy of his surgical method of lens dissection. He performed the first lens discission in 1887 and in 1894, he had successfully treated 44 patients. The late complication of retinal detachment, which was not understood until years later, eventually led surgeons to abandon the procedure until the recent improvements in both lenticular and retinal surgery techniques that led to better prognosis.     

Advances in the retinal regulation mechanism of form-deprivation myopia北大核心

形觉剥夺性近视(FDM)是由于视网膜接收不到清晰的物像,从而导致眼轴异常伸长,进而诱导近视发生。由于上睑下垂、先天性白内障、角膜混浊和玻璃体积血等原因导致的形觉剥夺引发的近视,其机制可能与在动物模型上观察到的FDM的机制类似。动物模型的研究已经证明了眼部生长和屈光发育的视觉引导以及视网膜调控的存在。视网膜是首先感知异常视觉信号的组织,探讨FDM发生发展机制的关键在于阐明异常的视觉信号输入如何被视网膜所感知并产生相应的生理病理改变。目前的研究已经确定了如多巴胺、视黄酸、血管活性肠肽、黑视蛋白等视网膜神经递质以及视网膜离子外排机制的重要作用。基因组学、蛋白质组学、代谢组学等技术发展使得从宏观层面了解形觉剥夺时视网膜发生的整体改变成为可能,为进一步探究FDM的视网膜调控机制提供了重要的数据支持。     

The efficacy and safety of modified Snyder–Thompson posterior scleral reinforcement in extensive high myopia of Chinese children

Background

To observe the efficacy and safety of modified Snyder–Thompson posterior scleral reinforcement in extensive high myopia of Chinese children. We had a retrospective design, and included a control group of children with natural progression of high myopia.

Methods

This study included 64 eyes in 41 Chinese children with extensive high myopia who underwent modified Snyder–Thompson posterior scleral reinforcement surgery (PSR group), and 17 eyes in 11 age- and myopia-matched children who wore spectacles (control group). The mean follow-up was 4.99?±?1.3 years in the PSR group and 4.48?±?1.3 years in the control group. Axial length, spherical equivalent (SE), uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA) and fundus examinations were recorded before and after treatment, and complications were noted.

Results

The mean change in SE at the end of the follow-up period was 1.5?±?1.44 diopters (D) and 3.02?±?1.57D in the PSR and control groups respectively. These changes were equivalent to an increase in axial length of 1.27?±?0.54 mm and 2.05?±?0.91 mm respectively. The PSR group showed less myopic progression and less eye elongation (p?<?0.001). A notable increase in UCVA was only found in the PSR group (p?=?0.0001). The improvement in BCVA was significantly greater in the PSR group (p?=?0.0354). There were no serious complications of PSR surgery.

Conclusion

The modified Snyder–Thompson PSR surgery was effective and safe in controlling extensive high myopia of Chinese children.     

Investigation of center–surround interaction in motion with reaction time for direction discrimination

How motion onset asynchrony (MOA) alters the effects of stimulus size on reaction time (RT) for direction discrimination of a drifting grating was examined. MOA is a delay from the stimulus onset to the onset of motion. Without MOA, RTs were found to increase as the stimulus size was increased at high contrast, but decrease with it at low contrast or at high noise levels. With MOA, however, RTs did not increase as the stimulus size increased even at high contrast. These results suggest that sudden stimulus onset evokes the increase of RTs with the increase of stimulus size at high contrast. RTs for direction discrimination of a drifting Gabor patch (the target) surrounded by a different drifting or a static grating as well as RTs for the target that was not surrounded by an additional grating were measured. The RTs for the target moving in the same or opposite direction as the motion of the surrounding grating were larger than those for the target with the static grating or no additional grating at moderate or high contrast. There was no significant difference between the RTs for the target moving in the same direction as the surrounding grating and the RTs for the target moving in the opposite direction. At low contrast and without MOA, however, the RTs for the target moving in the same direction as the surrounding grating were larger than those for the target moving in the opposite direction. These results suggest surround suppression at low contrast under some conditions. They also suggest that the decrease of RTs for discriminating motion direction of a drifting single Gabor patch with the increase of stimulus size at low contrast does not necessarily mean the absence of surround suppression.     

Who needs myopia control?

Myopia has become a major visual disorder among school-aged children in East Asia due to its rising prevalence over the past few decades and will continue to be a leading health issue with an annual incidence as high as 20%-30%. Although various interventions have been proposed for myopia control, consensus in treatment strategies has yet to be fully developed. Atropine and orthokeratology stand out for their effectiveness in myopia progression control, but children with rapid progression of myopia require treatment with higher concentrations of atropine that are associated with increased rates of side effects, or with orthokeratology that carries risk of significant complication. Therefore, improved risk assessment for myopia onset and progression in children is critical in clinical decision-making. Besides traditional prediction models based on genetic effects and environmental exposures within populations, individualized prediction using machine learning and data based on age-specific refraction is promising. Although emerging treatments for myopia are promising and some have been incorporated into clinical practice, identifying populations who require and benefit from intervention remains the most important initial step for clinical practice.     

Oculomotor function in nearwork-induced transiant and permanent myopia(Part Ⅱ)

2Nearwork-indutalpermanentmyopiaGenerally,itisaccePtedthatchildhoodm}opiapro-gressionisduetoaxialelongation,whichisnotcompen-satedbyreductionsincomealandcrystallinelenspow-ers[3,39,40,41].Untilrecenily,theomponentmechanismsthatpnduceLDMbecomeclear.Kent[70]reportedlongitu-dillaldata,foronesubject,showingthatcornealpowerin-creasedasmyopiaprogressedduringtheearyadultyears.GossandErickson[43]foundthatcorrelationsbetweencornealsteepeningandmyopiapropessionweresignificantinbothprincipalmeridians.…     

Progressing myopia in children: does it need treatment or not?

The purpose of the case study was to evaluate the remote consequences of a complex of laser and repeated surgical sclerorestorative procedures made in progressing myopia and its complications. Three hundred and forty-six children, aged 8-10, with rapidly progressing uncomplicated myopia of 4.25 to 9.5 D were shared between 2 groups. Two hundred and forty patients of the experimental group were made sclerorestorative procedures and transscleral low-energy laser stimulation of the ciliary muscle by means of infrared laser MACDEL-09. No such treatment was applied to patients of the control group. When indicated, preventive laser coagulation of the retina was made in both groups. The dynamic 10-year follow-up over the status of refraction and eye bottom showed that the complex scheme of repeated sclerorestorative procedures and low-energy laser treatment combined with preventive peripheral laser coagulation of the retina cut the rate of progressing myopia and prevented peripheral vitreoretinal dystrophy and retinal detachment in children and teenagers with progressing myopia.     

Progression and associated factors of lacquer cracks/patchy atrophies in high myopia: the Beijing Eye Study 2001–2011

Graefe's Archive for Clinical and Experimental Ophthalmology - To assess the development and progression of lacquer cracks/patchy atrophies (LCs/PAs) in high myopia. The case control study...     

How genetic is school myopia?

Myopia is of diverse aetiology. A small proportion of myopia is clearly familial, generally early in onset and of high level, with defined chromosomal localisations and in some cases, causal genetic mutations. However, in economically developed societies, most myopia appears during childhood, particularly during the school years. The chromosomal localisations characterised so far for high familial myopia do not seem to be relevant to school myopia. Family correlations in refractive error and axial length are consistent with a genetic contribution to variations in school myopia, but potentially confound shared genes and shared environments. High heritability values are obtained from twin studies, but rest on contestable assumptions, and require further critical analysis, particularly in view of the low heritability values obtained from parent-offspring correlations where there has been rapid environmental change between generations. Since heritability is a population-specific parameter, the values obtained on twins cannot be extrapolated to define the genetic contribution to variation in the general population. In addition, high heritability sets no limit to the potential for environmentally induced change. There is in fact strong evidence for rapid, environmentally induced change in the prevalence of myopia, associated with increased education and urbanisation. These environmental impacts have been found in all major branches of the human family, defined in modern molecular terms, with the exception of the Pacific Islanders, where the evidence is too limited to draw conclusions. The idea that populations of East Asian origin have an intrinsically higher prevalence of myopia is not supported by the very low prevalence reported for them in rural areas, and by the high prevalence of myopia reported for Indians in Singapore. A propensity to develop myopia in "myopigenic" environments thus appears to be a common human characteristic. Overall, while there may be a small genetic contribution to school myopia, detectable under conditions of low environmental variation, environmental change appears to be the major factor increasing the prevalence of myopia around the world. There is, moreover, little evidence to support the idea that individuals or populations differ in their susceptibility to environmental risk factors.     

Altered visual sensitivity in axial high myopia: a local postreceptoral phenomenon?

PURPOSE: The present study investigated retinal integrity in high myopia using spatial psychophysical tasks. METHODS: Ten axial high myopes (-8.5 to -11.5 D) and 10 age-matched control subjects (+/-1.0 D) were recruited. All participants underwent clinical examination and ocular biometry and demonstrated no visible macular disease with visual acuities better than 6/12. Foveal summation thresholds were determined for white and S-cone-isolating spots of various diameters up to 5.4 degrees and spatial contrast sensitivity to luminance sine wave gratings (0.5-9.7 cyc/deg). Data were analyzed after correction for the magnification induced by eye size and correcting lens power. RESULTS: Spatial summation for both white and S-cone-isolating spots showed a generalized loss of sensitivity at all spot sizes in myopes relative to control subjects (P = 0.01). Critical areas at maximum summation were significantly larger in myopes, for S-cone isolating spots only, after image size correction (P = 0.048). Sensitivity at maximum summation correlated negatively with vitreous chamber depth for both targets (P = 0.005). Sensitivities for S-cone and luminance spots also correlated (P < 0.001), indicating widespread dysfunction. Myopes displayed contrast sensitivity losses at high spatial frequencies (P 相似文献   

Macular Bruch’s membrane defects and other myopic lesions in high myopia

AIM: To compare the ocular fundus features of highly myopic eyes with and without macular Bruch’s membrane (BM) defects and investigate the associations between macular BM defects and other myopic lesions. METHODS: This retrospective, observational case series included 262 eyes (139 patients) with high myopia (HM) refractive error ≥-6.0 diopters (D) or axial length ≥26.5 mm from March 2019 to December 2019. The patients underwent a comprehensive ophthalmic examination, including swept-source optical coherence tomography (SS-OCT). The features of macular BM defects and other ocular fundus lesions were examined in OCT images. RESULTS: Totally 51 eyes (19.5%) were detected with macular BM defects, which were characterized by a lack of BM, retinal pigment epithelium (RPE), and an almost complete loss of photoreceptors or choriocapillaris. Eyes with macular BM defects had worse best-corrected visual acuity (BCVA) than those without (P<0.001). Dome-shaped macula (DSM, P=0.042), retinal cysts (P=0.006), choroidal neovascularization (CNV, P<0.001), choroidal defects and abnormality (P=0.003), scleral defects (P=0.015), scleral deformation (P=0.005), posterior staphyloma (P=0.011), and perforating vessels (P<0.001) occurred more frequently in eyes with macular BM defects. In multivariate analysis, the presence of macular BM defects remained the significant association with presence of DSM (P=0.013), scleral defects (P=0.015), posterior staphyloma (P=0.001), perforating vessels (P<0.001) and CNV (P=0.004). CONCLUSION: Macular BM defects has a prevalence of approximately 20% in HM and it has tight association with other myopic fundus lesions. BM might be crucial in the pathogenesis of myopic fundus lesions due to its biomechanical function. A comprehensive understanding of BM’s role is useful for further researches about myopic lesions.     

Matched optical quality comparison of 3-year results of PRK–MMC and phakic IOL implantation in the correction of high myopia

Aims

To compare 3-year results of PRK–MMC and phakic intraocular lens (PIOL) implantation in patients with >8.0 diopters (D) of myopia.

Methods

This study was conducted as a non-randomized clinical trial on 23 eyes treated with PIOL (Artiflex; group A) and 23 eyes treated with PRK–MMC (group B). This report compares 3-year treatment results in these two groups.

Results

At 3 years after surgery, uncorrected visual acuity was 0.02±0.06 LogMAR in group A and 0.04±0.07 LogMAR in group B (P=0.639). Mean best corrected visual acuity in group A (0.004±0.02) was better than group B (0.03±0.07 LogMAR) (P=0.035). Mean manifest refraction spherical equivalent was −0.16±0.21 and −0.09±0.20D (P=0.190), respectively. Mesopic contrast sensitivity (CS) in the spatial frequency of three cycle/degree (CS3) significantly decreased in both groups, but the reduction was significantly higher in group B (P=0.024). CS6 decreased significantly only in group B (P=0.019). Changes in CS12 and CS18 showed no significant inter-group difference. In group A, the increase in C6 trefoil (0.16±0.18 μm, P=0.003) and reduction in spherical aberration (SA; 0.16±0.08 μm, P<0.001) were statistically significant. In group B, the reduction in vertical coma (P=0.052), and increases in horizontal coma (P=0.044), coma (P<0.001), SA (P<0.001), and total higher order aberrations (P<0.001) were significant after surgery.

Conclusion

Based on 3-year results, PIOL implantation is a better choice than PRK–MMC for treating patients with >8.0D myopia. However, for patients with an inadequate aqueous depth, PRK–MMC can be an acceptable treatment option with a potential for decreased quality of vision.