To evaluate hyperreflective retinal spots (HRS), in normal subjects and diabetic patients without and with macular edema (diabetic macular edema, DME), on linear B-scans and corresponding en face ...image of spectral-domain optical coherence tomography.
Retrospective evaluation of images of 54 eyes/subjects (16 normal subjects, 19 diabetic patients without DME, and 19 with DME). On horizontal B-scan spectral-domain optical coherence tomography, passing through the center of the fovea, the following characteristics of HRS were evaluated: location (inner retina or outer retina), size (≤30 or >30 μm), reflectivity (similar to nerve fiber layer or to retinal pigment epithelium-Bruch complex), and presence or absence of back shadowing. On en face spectral-domain optical coherence tomography, the following patterns were evaluated: 1) isolated HRS (not corresponding to any visible lesion); 2) HRS corresponding to a segment of retinal capillary or microaneurysm wall; and 3) HRS corresponding to hard exudate. All gradings were performed twice by two graders in a masked fashion.
Size ≤30 μm, reflectivity similar to nerve fiber layer, and absence of back shadowing were associated with absence of vessels or any other lesion on en face image (P = 0.0001 for all). Size >30 μm, reflectivity similar to retinal pigment epithelium-Bruch complex, presence of back shadowing, and location in the outer retina were all associated with presence of hard exudate on en face imaging (P < 0.0001 for all). Multiple logistic regression analysis showed that HRS present in the inner retina (P < 0.0001), size >30 μm (P = 0.0029), and presence of back shadowing (P < 0.0001) are directly associated with presence of microaneurysms on en face image. Intragrader and intergrader repeatability were excellent for all evaluations.
Hyperreflective retinal spots ≤30 μm, reflectivity similar to nerve fiber layer, and absence of back shadowing may represent activated microglial cells; HRS >30 μm, reflectivity similar to retinal pigment epithelium-Bruch complex, presence of back shadowing, and location in the outer retina may represent hard exudate; HRS >30 μm, presence of back shadowing, and location in the inner retina may represent microaneurysms. These hypotheses may be tested in further studies.
•Repolarization alternans is an ECG phenomenon only qualitatively defined.•Each method relies on its implicit definition to quantify repolarization alternans.•With a simulation, we highlighted the ...quantitative definitions of each method.•Such knowledge helps interpretation of differences among studies.
The qualitative definition of repolarization alternans (RA) as an every-other-beat alternation of the repolarization amplitude allows several possible quantitative characterizations of RA. In the absence of a standardization, any correct comparison among quantitative outputs by different automatic methods requires knowledge of the differences in the RA parameterization at the basis of their algorithms. Thus, aim of the present study was to investigate the kind of information provided by five methods, namely the fast Fourier spectral method (FFTSM), the complex demodulation method (CDM), the modified moving average method (MMAM), the Laplacian likelihood ratio method (LLRM) and the heart-rate adaptive match filter method (AMFM) when characterizing RA in terms of its amplitude and location. Eight synthetic ECG recordings affected by stationary RA with uniform and triangular profiles localized along the ST segment, over the T wave, at the end of the T wave and all along the JT segment, respectively, were considered. Results indicate that quantitative RA characterization is method dependent. More specifically, the FFTSM and the LLRM provide a measure that matches the root mean square of the RA profile over the JT segment. Instead, the CDM and the AMFM compute RA amplitude as the mean value of the RA profile over the JT segment. Eventually, the MMAM provides the maximum amplitude difference between consecutive beats along repolarization. RA location is homogeneously among methods, since they all provide the time instant in correspondence of which the center of mass of the alternation occurs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Obese adults frequently exhibit a low-grade inflammation and insulin resistance, which have been hypothesized to be established early in childhood. Aim of this study was to evaluate the age-dependent ...relationships between inflammatory state and insulin resistance in obese adolescents and adults. Clinical and metabolic parameters, circulating adipokines (TNF-α, adiponectin, and leptin), ghrelin, their leukocyte receptors (TNFR1, ADIPOR2, OBRL and GHSR1a), and acute phase reactants (CRP and white blood cells) were assessed in lean and obese adolescents compared with the adult counterparts. Only obese adults had higher HOMA-IR, insulin, and triglycerides compared to the lean group. An inflammatory state was present in obese adolescents and adults, as demonstrated by the higher values of CRP and neutrophils. There were no group differences in circulating levels of TNF-α and leukocyte expression of TNFR1. Adiponectin concentrations and leukocyte expression of ADIPOR2 were higher in the lean groups than in the corresponding obese counterparts. For leptin and leukocyte expression of OBRL, the results were opposed. Circulating levels of ghrelin were higher in lean adolescents and adults than the related lean groups, while there was a higher leukocyte expression of GHSR1a in (only) lean adults than obese adults. When the analysis was performed in (lean or obese) adults, TNF-α, neutrophils, leptin, and GHSR1a were predictors of HOMA-IR. None of the considered independent variables accounted for the degree of insulin resistance in the adolescent group. In conclusion, a dissociation between the low-grade inflammation and insulin resistance is supposed to exist in the early phases of obesity.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Purpose
To evaluate functional changes (retinal sensitivity and fixation characteristics) determined by microperimetry in patients with early and intermediate AMD over 6 years.
Methods
Prospective, ...longitudinal follow-up (FU) study of 16 patients (29 eyes) with early and intermediate AMD (AREDS 2 and AREDS 3 classification). All eyes underwent: complete ophthalmic examination with best corrected visual acuity (BCVA) determination, color fundus photo (CFP), optical coherence tomography and microperimetry. All CFP were evaluated by two retinal specialists masked to functional data for changes in severity of clinical features over the course of FU.
Results
Of 17 eyes graded as AREDS 2 at baseline, 14 (82.35 %) remained stable, and 3 (18.75 %) progressed to AREDS 3. Of 12 eyes graded as AREDS 3 at baseline, 10 remained stable (83.33 %), and 2 (16.67 %) progressed to AREDS 4. Mean BCVA significantly deteriorated in both AREDS 2 (
p
= 0.006) and AREDS 3 (
p
= 0.016), with greater decrease in AREDS 3 (
p
= 0.01)6. Mean retinal sensitivity (RS) significantly decreased over time in both AREDS 2 (
p
< 0.0001) and AREDS 3 grou
p
(
p
= 0.002), with greater decrease in AREDS 3 (
p
= 0.006). The mean number of dense scotomas did not change in AREDS 2 (
p
= 0.3), but significantly increased in the AREDS 3 group (
p
= 0.035). Points with decreased RS were located in all but the central point (
p
< 0.0001 for all), without significant differences in number among rings. In the AREDS 2 group, fixation stability remained unchanged. In the AREDS 3 group, four eyes deteriorated from stable to unstable fixation at FU (
p
= 0.045).
Conclusion
A significant deterioration in RS is reported in early and intermediate AMD eyes, whereas fixation stability changed only in intermediate AMD (AREDS 3) over long-term follow-up. Microperimetry examination can become a new functional biomarker in early and intermediate AMD patients.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract An association between heterogeneity of repolarization alternans (RA) and cardiac electrical instability has been reported. Characterization of RA in health and identification of ...physiological RA heterogeneity may help discrimination of abnormal RA cases more likely associated to arrhythmic events. Thus, aim of the present study was the identification of a physiological RA region in terms of mean temporal location (MRAD) with respect to the T apex, and mean amplitude (MRAA), by application of our heart-rate adaptive match filter method to clinical ECG recordings from 51 control healthy (CH) subjects and 43 acute myocardial infarction (AMI) patients. Results indicate that RA occurring within the first half of the T wave is dominant in both CH and AMI populations (74.5% and 53.5% of cases, respectively; P < 0.05). Definition of physiological RA region in the MRAD vs. MRAA plane (−83 ms ≤ MRAD ≤ 23 ms, 0 ≤ MRAA ≤ 30 μV) provided 0% and 32.6% abnormal RA cases among the CH subjects and AMI patients, respectively. We conclude that myocardial infarction may associate with an RA occurring early (MRAD < −83 ms) or late (MRAD > 23 ms) along the JT segment, in addition or in alternative to an abnormally high RA amplitude (MRAA > 30 μV).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Purpose:
To describe, retrospectively, the visual outcome, feasibility, and safety of cataract surgery in a pediatric population affected by iatrogenic cataract, secondary to systemic oncological ...treatment for malignancies other than retinoblastoma.
Methods:
Young patients, affected by radiation-induced cataract, who were referred to the San Paolo Ophthalmic Center in Padova between 2010 and 2017, were included in the study. All patients had previously received radiotherapy and/or chemotherapy treatment for malignancies, between 2004 and 2013. All medical records of infants who underwent cataract surgery were accurately reviewed.
Results:
Eighteen eyes out of 11 patients included in the study underwent cataract surgery. The mean age at surgery was 9.7 ± 3.6 years. The interval between tumor diagnosis and cataract development was around 3 years. Mean follow-up after surgery was 15.4 ± 6.3 months. All eyes underwent posterior chamber intraocular lens implantation, posterior capsulotomy, and anterior vitrectomy in one time surgery. No intraoperative complications were shown. Post-operatively, only one eye received laser capsulotomy due to posterior capsule opacification. At the end of follow up, best-corrected visual acuity was 20/20 (LogMAR 0) in all eyes and significantly improved (p < 0.01) compared to baseline.
Conclusions:
Iatrogenic-cataract surgery in pediatric oncological patients is a safe and effective way to improve visual acuity. Posterior capsulotomy and anterior vitrectomy at the time of surgery reduce the rate of posterior lens opacification and guarantee an excellent visual acuity in these patients.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Abstract Microvolt T-wave alternans (TWA), consisting of every-other-beat changes in ECG T-wave morphology, is an index of susceptibility to malignant ventricular arrhythmias, requiring automatic ...techniques to be identified. Five of these, namely, fast-Fourier-transform spectral method (FFTSM), complex-demodulation method (CDM), modified-moving-average method (MMAM), Laplacian-likelihood-ratio method (LLRM) and adaptive-match-filter method (AMFM), were applied here to simulated and sample clinical data. The aim was to compare individual methods ability to properly identify stationary and time-varying TWA, avoiding false-positive detections. The MMAM provided false-positive TWA when applied to simulated ECGs affected by amplitude variability, but TWA. Stationary TWA was properly quantified by the MMAM and, occasionally, underestimated by all other methods. The AMFM properly identified time-varying TWA. By contrast, the FFTSM detected not-stationary TWA as stationary, the MMAM introduced a time-delay in the estimated TWA-amplitude signal, while the CDM and LLRM were reliable only in the presence of slow-varying TWA. Altogether, the AMFM accomplished the best compromise between the needs to avoid false-positive TWA and to detect and characterize true-positive TWA. Results of our simulation approach were useful to explain different TWA levels measured by each competing methods applied to sample Holter ECGs from healthy subjects and coronary artery disease patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract The aim was to investigate the effect of interferences surviving preprocessing (residual noise, baseline wanderings, respiration modulation, replaced beats, missed beats and T-waves ...misalignment) on automatic identification of T-wave alternans (TWA), an ECG index of risk for sudden cardiac death. The procedures denominated fast-Fourier-transform spectral method (FFTSM), complex-demodulation method (CDM), modified-moving-average method (MMAM), Laplacian-likelihood-ratio method (LLRM), and adaptive-match-filter method (AMFM) were applied to interferences-corrupted synthetic ECG tracings and Holter ECG recordings from control-healthy subjects (CH-group; n = 25) and acute-myocardial-infarction patients (AMI group; n = 25). The presence of interferences in simulated data caused detection of false-positive TWA by all techniques but the FFTSM and AMFM. Clinical applications evidenced a discrepancy in that the FFTSM and LLRM detected no more than one TWA case in each population, whereas the CDM, MMAM, and AMFM detected TWA in all CH-subjects and AMI-patients, with significantly lower TWA amplitude in the former group. Because the AMFM is not prone to false-positive TWA detections, the latter finding suggests TWA as a phenomenon having continuously changing amplitude from physiological to pathological conditions. Only occasional detection of TWA by the FFTSM and LLRM in clinics can be ascribed to their limited ability in identifying TWA in the presence of interferences surviving preprocessing.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To determine if aqueous humour (AH) concentrations of Retinal Pigment Epithelium (RPE)'s biomarkers are modified after subthreshold micropulse laser (SMPL) treatment of diabetic macular edema (DME).
...Naïve DME and healthy subjects were enrolled. All DME patients received SMPL treatments (577-nm yellow light, 5% duty cycle of 0.2 s, power 250 mW), according to study protocol. AH of DME eyes was sampled at baseline and periodically after first SMPL treatment. Control eyes were sampled before cataract surgery. Pigment Epithelium Derived Factor (PEDF) and Erythropoietin (EPO) were quantified with glass-chip protein array.
Eighteen DME patients (central retinal thickness ≤ 400 μm on Spectral Domain Optical Coherence Tomography (SD-OCT)) and ten controls were enrolled. The main exclusion criteria were high refractive error, proliferative diabetic retinopathy, glaucoma and neurodegenerative disorders. PEDF concentration was decreased in DME patients at baseline versus controls (
=0.012), while EPO was increased (
=0.029). Both molecules' concentrations remained stable during follow-up after treatments, compared with DME-baseline.
: The AH concentrations of RPE biomarkers were significantly different in DME treatment-naïve eyes versus controls. The expression of PEDF and EPO remained unchanged after treatments with SMPL in DME eyes. These data are relevant for future research and applications of SMPL.
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