Elements such as zinc, iron, copper, sulphur and phosphorus have been identified in retinal layers and implicated in vital retinal functions. Regarding mineral composition of epiretinal membranes ...(ERMs), literature is lacking. This study aimed to analyze both mineral composition and anatomical ultrastructure of ERMs to clarify the pathophysiology of this disease.
Twenty ERMs (10 diabetic ERMs and 10 idiopathic ERMs) from 20 patients were harvested during pars plana vitrectomy. Scanning Electron Microscopy (SEM) was used to investigate the anatomical ultrastructure of the peeled ERMs. Mineral composition was analyzed using energy-dispersive spectrometry (EDS). The most frequent elements were evaluated in relation to appearance of ERMs analyzed at SEM and at OCT images.
Sulphur was the most frequent element found (in 80% of the samples), followed by sodium (50%) and phosphorus (45%). The presence of these elements was not significantly different between diabetic and idiopathic ERMs (P >0.05). Using SEM we found a folded tissue in all ERMs, except in 4 ERMs, where we observed only a smooth tissue. There was a trend of sodium to be more frequent in ERMs with folded layers at SEM examination.
Several elements were identified in ERMs, and sulphur, sodium and phosphorus were the most frequent ones. This finding may help to understand their role in the physiopatology of epiretinal proliferation and in glial activation.
This review addresses the complexities of type 1 diabetes (T1D) and its associated complications, with a particular focus on diabetic retinopathy (DR). This review outlines the progression from ...non-proliferative to proliferative diabetic retinopathy and diabetic macular edema, highlighting the role of dysglycemia in the pathogenesis of these conditions. A significant portion of this review is devoted to technological advances in diabetes management, particularly the use of hybrid closed-loop systems (HCLSs) and to the potential of open-source HCLSs, which could be easily adapted to different patients' needs using big data analytics and machine learning. Personalized HCLS algorithms that integrate factors such as patient lifestyle, dietary habits, and hormonal variations are highlighted as critical to reducing the incidence of diabetes-related complications and improving patient outcomes.
Introduction/aims
Non-arteritic anterior ischemic optic neuropathy (NAION) is an acute infarction of the prelaminar anterior optic disc, resulting from the occlusion of posterior ciliary arteries. ...Here, we evaluated the correlation between structural and vascular features in a case of resolved NAION.
Methods
Observational case report.
Results
A 50-year-old male patient was referred at an Eye clinic due to an altitudinal visual field defect in the left eye, occurred 9 months before. Fundus examination was unremarkable, while structural SD-OCT reveals retinal nerve fiber layer (RNFL), ganglion cell complex (GCC) thinning associated with reduction of peripapillary vascular density at OCT Angiography.
Discussion
We found a precise spatial correlation among RNFL and GCC thinning, peripapillary vascular reduction and visual field defects. This case demonstrates that OCTA represents a new, valid and non-invasive imaging technique in the diagnosis and follow-up of NAION, even after the resolution of the acute phase, in the absence of clinical signs at fundus examination.
Tears are exceptionally rich sources of information on the health status of the eyes, as well as of whole body functionality, due to the presence of a large variety of salts and organic components ...whose concentration can be altered by pathologies, eye diseases and/or inflammatory processes. Surface enhanced Raman spectroscopy (SERS) provides a unique method for analyzing low concentrations of organic fluids such as tears. In this work, a home-made colloid of gold nanoparticles has been used for preparing glass substrates able to efficiently induce an SERS effect in fluid samples excited by a He⁻Ne laser ( λ = 633 nm). The method has been preliminary tested on Rhodamine 6G aqueous solutions at different concentrations, proving the possibility to sense substance concentrations as low as few μ M, i.e., of the order of the main tear organic components. A clear SERS response has been obtained for human tear samples, allowing an interesting insight into tear composition. In particular, aspartic acid and glutamic acid have been shown to be possible markers for two important human tear components, i.e., lactoferrin and lysozyme.
Objectives
To evaluate the retinal and choriocapillaris vascular networks in macular region and the central choroidal thickness (CCT) in patients affected by Huntington disease (HD), using optical ...coherence tomography angiography (OCTA) and enhanced depth imaging spectral-domain OCT (EDI SD-OCT).
Methods
We assessed the vessel density (VD) in superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) using OCTA, while CCT was measured by EDI SD-OCT.
Results
Sixteen HD patients (32 eyes) and thirteen healthy controls (26 eyes) were enrolled in this prospective study. No significant difference in retinal and choriocapillaris VD was found between HD patients and controls while CCT turned to be thinner in patients respect to controls. There were no significant relationships between OCTA findings and neurological parameters.
Conclusion
The changes in choroidal structure provide useful information regarding the possible neurovascular involvement in the physiopathology of HD. Choroidal vascular network could be a useful parameter to evaluate the vascular impairment that occurs in this neurodegenerative disease.
To assess the efficacy of vitrectomy in degenerative and tractional lamellar macular holes (LMHs) by meta-analysis of published studies.
PubMed, Medline and Embase databases were searched up to May ...2020. Included cohorts were divided into three groups: degenerative LMH group, lamellar hole associated epiretinal proliferation (LHEP) group and tractional LMH group. LHEP is likely to be associated with degenerative LMHs, but less commonly could be associated with mixed LMHs. To reduce risk of possible misclassification bias, eyes with LHEP which could not have been precisely classified by the authors, were included into the LHEP group. The primary outcome was to investigate the visual change following primary vitrectomy in the degenerative LMH and LHEP group versus the tractional LMH group. A sensitivity analysis excluding the LHEP group was also performed on the primary outcome. Mean difference (MD) in best corrected visual acuity between baseline and post-treatment was calculated, along with 95% confidence interval (CI). Rate of incidence of post-operative full-thickness macular hole (FTMH) was assessed as secondary outcome.
Thirteen studies were included. Pooled analyses including all groups showed a significant visual improvement following vitrectomy (pre-post MD = -0.17;95%CI = -0.22,-0.12;p<0.001), with no difference in visual improvement between the degenerative LMH and LHEP group and the tractional LMH group. The sensitivity analysis excluding LHEP group confirmed no difference in visual change between the degenerative LMH group (pre-post MD = -0.18;95%CI = -0.24,-0.12;p<0.001) and the tractional LMH group (MD = -0.16;95%CI = -0.26,-0.07;p<0.001). The incidence rate of post-operative FTMH was higher in the degenerative LMH and LHEP group than in the tractional LMH group (p = 0.002).
Primary vitrectomy for LMH ensured a favorable visual outcome, with no difference in visual gain between degenerative and tractional LMHs. However, a higher incidence of post-operative FTMHs was found in eyes with the degenerative LMH subtype.
To evaluate changes in anterior corneal optical density and the refractive index after photorefractive keratectomy (PRK) using a rotating Scheimpflug system.
Department of Ophthalmology, University ...Federico II, Naples, Italy.
Comparative case series.
Anterior corneal optical density was evaluated with a rotating Scheimpflug system at baseline and 3 months and 12 months after PRK in eyes with a refractive error between -6.00 diopters (D) and -12.00 D (study group). A control group of unoperated eyes with the same refraction range was used to calculate corneal optical density and the Gladstone-Dale constant in unoperated eyes using the Gladstone-Dale formula. In the study group, changes in the anterior corneal optical density were evaluated over time and variations in the anterior corneal refractive index were obtained using the Gladstone-Dale constant.
The study group comprised 37 eyes and the control group, 200 eyes. In the study group, the mean anterior corneal optical density and refractive index, respectively, were 27.71 ± 4.39 and 1.360 ± 0.05 at baseline, 37.812 ± 12.31 and 1.491 ± 0.16 after 3 months (P<.001 compared with baseline), and 26.29 ± 4.93 and 1.341 ± 0.06 after 12 months (P=.03 compared with baseline). The mean corneal optical density in the control group was 27.71 ± 4.31 (SD), and the resultant Gladstone-Dale constant was 0.013.
An early increase and a subsequent reduction in anterior corneal optical density and the refractive index were present in myopic eyes during 1 year after PRK.
Uveal melanoma is the most common primary intraocular malignancy. The aim of this retrospective study was to report the results after ruthenium-106 (Ru-106) plaque brachytherapy for uveal melanoma in ...terms of tumor control, visual acuity, radiation-related complications, tumor recurrence, metastases, and patients' survival rate during 4 years' follow-up. A total of 355 eyes from 355 patients have been treated with Ru-106 plaque brachytherapy for uveal melanoma between February 2011 and March 2020. Five patients were lost to follow-up, and then 350 eyes of 350 patients (mean age 58 ± 11 years) were enrolled in this retrospective study. All patients underwent a complete ophthalmic examination including echography and spectral domain-optical coherence tomography. The mean follow-up was 4 years (3 months to 9 years). After treatment, the mean tumor thickness was reduced to 1.75 ± 0.21 mm. Radiation complications were found in 63% of patients: 38% showed radiation maculopathy, 11% had optic neuropathy, and 14% developed cataracts. Cancer-free survival was 99%, 97%, and 85%, respectively, at 5, 7, and 9 years. Ru-106 plaque brachytherapy represents a reliable treatment of uveal melanoma. This technique is valid and safe with a low rate of ocular complications during a long-term follow-up.
Background
To determine the correlation between the area of morphological changes on the macular surface, the depth of intraretinal changes and the best-corrected visual acuity (BCVA) in patients ...with idiopathic epiretinal membrane.
Methods
In this prospective cross-sectional study, 38 patients underwent BCVA testing with a Snellen eye chart. The depth of traction, photoreceptor outer segment layer (PROS) thickness, central macular thickness (CMT) and presence of intraretinal cysts were measured using the Avanti RTVue XR and 3D Widefield Enface OCT instruments. Enface sections were performed at the inner limiting membrane (ILM) line level (ILM offset). Patients were categorized into two groups: in group 1 (
n
= 21), the depth of traction was within 90 μm from the ILM, and in group 2 (
n
= 17) it was beyond 90 μm from the ILM. The main outcome measure was the correlation between area of epiretinal traction and BCVA according to the depth of traction.
Results
In group 1, the depth of traction was 55.15 ± 14.28 μm, the area of traction was 38.95 ± 13.63 mm
2
, PROS thickness was 51.20 ± 7.23 μm, and CMT was 362.65 ± 41.08 μm. In group 2, the depth of traction was 112.24 ± 10.89 μm, the area of traction was 25.18 ± 4.07 mm
2
, PROS thickness was 50.24 ± 9.01 μm, and mean CMT was 534.29 ± 126.81 μm. Statistically significant differences in depth of traction, area of traction and CMT were found between the two groups (
P
< 0.001). The relationship between structure and function between the area of traction and BCVA was better explained in group 2 (
r
= 0.814,
P
< 0.001).
Conclusions
We found that intraretinal changes were induced by the ERM, and varied according to the depth of traction measured with en face analysis. In the case of traction deeper than 90 μm, we found a significant correlation between the inner area of the epiretinal traction and BCVA. We believe that retinal stress induced by epiretinal traction is better characterized by combining information provided by sagittal and transverse OCT scans, thus defining its prognostic significance in ERM.
The small Ras-related GTPase Rab-28 is highly expressed in photoreceptor cells, where it possibly participates in membrane trafficking. To date, six alterations in the
gene have been associated with ...autosomal recessive cone-rod dystrophies. Confirmed variants include splicing variants, missense and nonsense mutations. Here, we present a thorough phenotypical and genotypical characterization of five individuals belonging to four Italian families, constituting the largest cohort of
patients reported in literature to date. All probands displayed similar clinical phenotype consisting of photophobia, decreased visual acuity, central outer retinal thinning, and impaired color vision. By sequencing the four probands, we identified: a novel homozygous splicing variant; two novel nonsense variants in homozygosis; a novel missense variant in compound heterozygous state with a previously reported nonsense variant. Exhaustive molecular dynamics simulations of the missense variant p.(Thr26Asn) in both its active and inactive states revealed an allosteric structural mechanism that impairs the binding of Mg
, thus decreasing the affinity for GTP. The impaired GTP-GDP exchange ultimately locks Rab-28 in a GDP-bound inactive state. The loss-of-function mutation p.(Thr26Asn) was present in a compound heterozygosis with the nonsense variant p.(Arg137*), which does not cause mRNA-mediated decay, but is rather likely degraded due to its incomplete folding. The frameshift p.(Thr26Valfs4*) and nonsense p.(Leu13*) and p.(Trp107*) variants, if translated, would lack several key structural components necessary for the correct functioning of the encoded protein.
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