Ocular Refraction at Birth and Its Development During the First Year of Life in a Large Cohort of Babies in a Single Center in Northern Italy

The purpose of this study was to investigate refraction at birth and during the first year of life in a large cohort of babies born in a single center in Northern Italy. We also aimed to analyze refractive errors in relation to the gestational age at birth. An observational ophthalmological assessment was performed within 24 h of birth on 12,427 newborns. Refraction was examined using streak retinoscopy after the administration of tropicamide (1%). Values in the range of between +0.50 ≤ D ≤ +4.00 were defined as physiological refraction at birth. Newborns with refraction values outside of the physiological range were followed up during the first year of life. Comparative analyses were conducted in a subgroup of babies with known gestational ages. The following distribution of refraction at birth was recorded: 88.03% of the babies had physiological refraction, 5.03% had moderate hyperopia, 2.14% had severe hyperopia, 3.4%, had emmetropia, 0.45%, had myopia, 0.94% had astigmatism, and 0.01% had anisometropia. By the end of the first year of life, we observed reductions in hyperopia and astigmatism, and stabilization of myopia. Preterm babies had a four-fold higher risk of congenital myopia and a three-fold higher risk of congenital emmetropia as compared to term babies. Refraction profiles obtained at birth changed during the first year of life, leading to a normalization of the refraction values. Gestational age at birth affected the incidence of refractive errors and amblyopia

Prevalance study of glaucoma in Malta and Gozo

A glaucoma survey was carried out in Malta and Gozo. Using non-contact pulseair tonometer, 2245 participants selected on a random basis, aged 40 years and above, were examined and 3.29% were found to have glaucoma. Among them 1.69% were newly detected glaucoma cases. The main risk factors were diabetes mellitus in the personal past history and glaucoma in the family history. Age was confirmed to be a risk factor, but arterial hypertension and myopia could not be proved as risk factors. About 4000 glaucoma cases were estimated to be present in Malta and Gozo at the time of the survey. Some other ocular conditions were also found in relatively high percentages: cataract -3.3%, myopic maculopathy -2.9% and diabetic retinopathy -1.5%.peer-reviewe

Myopes have significantly higher serum melatonin concentrations than non-myopes

Purpose Experimental animal models of myopia demonstrate that higher melatonin (Mel) and lower dopamine (DA) concentrations actively promote axial elongation. This study explored the association between myopia and serum concentrations of DA and Mel in humans. Methods Morning serum concentrations of DA and Mel were measured by solid phase extraction‐liquid chromatography‐tandem mass spectrometry from 54 participants (age 19.1 ± 0.81 years) in September/October 2014 (phase 1) and March/April 2016 (phase 2). Axial length (AL), corneal radii (CR) and spherical equivalent refraction (SER) were also recorded. Participants were defined as myopic if non‐cycloplegic spherical equivalent refractive error ≤−0.50 DS at phase 1. Results Nine participants were lost to follow up. Mel concentrations were measurable for all myopes (phase 1 n = 25, phase 2 n = 22) and non‐myopes (phase 1 n = 29, phase 2 n = 23). SER did not change significantly between phases (p = 0.51). DA concentrations were measurable for fewer myopes (phase 1 n = 13, phase 2 n = 12) and non‐myopes (phase 1 n = 23, phase 2 n = 16). Myopes exhibited significantly higher Mel concentrations than non‐myopes at phase 1 (Median difference: 10 pg mL−1, p < 0.001) and at phase 2 (Median difference: 7.3 pg mL−1, p < 0.001) and lower DA concentrations at phase 2 (Median difference: 4.7 pg mL−1, p = 0.006). Mel concentrations were positively associated with more negative SER (all r ≥ −0.53, all p < 0.001), longer AL (all r ≥ 0.37, all p ≤ 0.008) and higher AL/CR ratio (all r ≥ 0.51, all p < 0.001). Conclusion This study reports for the first time in humans that myopes exhibit higher serum Mel concentrations than non‐myopes. This may indicate a role for light exposure and circadian rhythm in the human myopic growth mechanism. Further research should focus on younger cohorts exhibiting more dynamic myopic progression and explore the profile of these neurochemicals alongside evaluation of sleep patterns in myopic and non‐myopic groups

Genome-wide analysis points to roles for extracellular matrix remodeling, the visual cycle, and neuronal development in myopia

Myopia, or nearsightedness, is the most common eye disorder, resulting primarily from excess elongation of the eye. The etiology of myopia, although known to be complex, is poorly understood. Here we report the largest ever genome-wide association study (43,360 participants) on myopia in Europeans. We performed a survival analysis on age of myopia onset and identified 19 significant associations (p < 5e-8), two of which are replications of earlier associations with refractive error. These 19 associations in total explain 2.7% of the variance in myopia age of onset, and point towards a number of different mechanisms behind the development of myopia. One association is in the gene PRSS56, which has previously been linked to abnormally small eyes; one is in a gene that forms part of the extracellular matrix (LAMA2); two are in or near genes involved in the regeneration of 11-cis-retinal (RGR and RDH5); two are near genes known to be involved in the growth and guidance of retinal ganglion cells (ZIC2, SFRP1); and five are in or near genes involved in neuronal signaling or development. These novel findings point towards multiple genetic factors involved in the development of myopia and suggest that complex interactions between extracellular matrix remodeling, neuronal development, and visual signals from the retina may underlie the development of myopia in humans

Posterior corneal surface stability after femtosecond laser-assisted keratomileusis

The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue

The Cone Dysfunction Syndromes

The cone dysfunction syndromes are a heterogeneous group of inherited, predominantly stationary retinal disorders characterised by reduced central vision, and varying degrees of colour vision abnormalities, nystagmus and photophobia. This review details the following conditions: complete and incomplete achromatopsia, blue-cone monochromatism, oligocone trichromacy, bradyopsia, and Bornholm eye disease. We describe the clinical, psychophysical, electrophysiological and imaging findings that are characteristic to each condition, in order to aid their accurate diagnosis, as well as highlight some classically held notions about these diseases that have come to be challenged over recent years. The latest data regarding the genetic aetiology and pathological changes observed in the cone dysfunction syndromes are discussed, and, where relevant, translational avenues of research, including completed and anticipated interventional clinical trials, for some of the diseases described herein will be presented. Finally, we briefly review the current management of these disorders

Human PrimPol mutation associated with high myopia has a DNA replication defect

PrimPol is a primase-polymerase found in humans, and other eukaryotes, involved in bypassing lesions encountered during DNA replication. PrimPol employs both translesion synthesis and repriming mechanisms to facilitate lesion bypass by the replisome. PrimPol has been reported to be a potential susceptibility gene associated with the development of myopia. Mutation of tyrosine 89 to aspartic acid (PrimPolY89D) has been identified in a number of cases of high myopia, implicating it in the aetiology of this disorder. Here, we examined whether this mutation resulted in any changes in the molecular and cellular activities associated with human PrimPol. We show that PrimPolY89D has a striking decrease in primase and polymerase activities. The hydrophobic ring of tyrosine is important for retaining wild-type extension activity. We also demonstrate that the decreased activity of PrimPolY89D is associated with reduced affinities for DNA and nucleotides, resulting in diminished catalytic efficiency. Although the structure and stability of PrimPolY89D is altered, its fidelity remains unchanged. This mutation also reduces cell viability after DNA damage and significantly slows replication fork rates in vivo. Together, these findings establish that the major DNA replication defect associated with this PrimPol mutant is likely to contribute to the onset of high myopia

Detection of pathological myopia by PAMELA with texture-based features through an SVM approach

10.1260/2040-2295.1.1.1Journal of Healthcare Engineering111-1