Purpose
Keratoconus is a potentially blinding condition that slowly deforms the cornea in young people. Despite the increasing prevalence of keratoconus, the exact aetiology of the condition is ...unknown. This first systematic review examines the evidence of eye rubbing and its association with keratoconus and presents the findings of the meta-analysis.
Methods
Two independent reviewers searched the electronic databases for all potential articles published from 1st of January 1900 to 31st of July 2020 on eye rubbing and keratoconus. The researchers assessed the methodological quality of the studies using the Newcastle-Ottawa scale for observational studies. The assessment for statistical heterogeneity was estimated using chi-square and
I
-square (
I
2
) tests. A
p
value of < 0.05 was considered as statistically significant and
I
2
< 30% as homogenous. Begg funnel plot was used to interpret the asymmetry or small study effects.
Results
Eight case-control studies were included in this systematic review. Two studies assessed eye rubbing without odds ratios and thus were excluded. The pooled odds ratios for the six remaining studies included in the meta-analysis was 6.46 (95% CI 4.12–10.1). The study results were heterogenous (
I
2
= 71.69 95% CI 35.14–87.88). All the studies scored moderate quality methodology on the Newcastle-Ottawa scale. Begg funnel plot showed asymmetry supporting heterogeneity.
Conclusion
Eye rubbing showed consistent association with keratoconus. However, the current evidence is limited to only a small number of case-control studies which present as heterogeneous and of sub-optimal methodological quality. Additionally, the cause-effect temporal relationship cannot be determined. Further studies are needed to address this intricate relationship of eye rubbing and its induction, ongoing progression, and severity of keratoconus.
The growth of highly inhomogeneous samples is presented as a suitable way to investigate the continuous evolution of self-assembled InAs quantum dots as a function of the thickness of deposited ...material. A single specific sample allowed a direct comparison of the structural and optical properties of the strained islands using atomic-force microscopy and low-temperature photoluminescence.
This study aimed to evaluate and compare visual outcomes, spectacle independence, and patient satisfaction on bilaterally implanted Vivity extended depth-of-focus (EDOF) or monofocal intraocular ...lenses (IOLs) after cataract surgery in patients with early glaucoma.
In this retrospective, non-randomized, interventional cohort study, patients with early glaucoma undergoing cataract surgery received bilateral implantation of either EDOF (AcrySof IQ Vivity; Alcon) or monofocal (Clareon/SN6ATx/SN60WF; Alcon) IOLs. The primary outcome was monocular uncorrected intermediate visual acuity (UIVA). The secondary outcomes were monocular uncorrected distance (UDVA) and near (UNVA) visual acuity, spectacle independence, patient satisfaction, and photic phenomena. Fifty-eight eyes from 29 patients, including 32 eyes in the EDOF group and 26 eyes in the monofocal group, were included in the study.
UIVA (0.06 ± 0.16 versus 0.39 ± 0.10 LogMAR; P < 0.001) and UNVA outcomes (0.29 ± 0.10 versus 0.55 ± 0.18 LogMAR; P < 0.001) were significantly better in the EDOF group than in the monofocal group, respectively. There was no difference in UDVA and corrected distance visual acuity outcomes between the groups (P > 0.05), but both spectacle independence and patient satisfaction scores were significantly higher in the EDOF group (P < 0.001 and P < 0.05, respectively). There was no difference in self-reported photic phenomena.
Bilaterally implanted EDOF IOLs provided excellent distance vision and better intermediate and near vision than monofocal IOLs in patients with early glaucoma. Spectacle independence and patient satisfaction were significantly higher in patients who received EDOF IOLs. Photic phenomena were rare and seldom bothersome.
We present a systematic investigation of the capacitance–voltage measurements and Raman scattering on a multilayer InAs/GaAs self-assembled quantum dots system annealed at different temperatures. We ...observed a decrease of the electrical coupling of the electrons trapped in the dots located in the different layers. Raman scattering revealed the modifications of the dots morphology which influenced on the observed increase of the localization of electrons in the dots after the annealing process. We also observed that the annealing at 600°C altered the plane of the dots into layers of an In
x
Ga
1-
x
As alloy.
Purpose: A comparison of axial length estimates using applanation A‐scan ultrasound and the Zeiss IOLMaster was conducted. The accuracy in predicting postoperative refraction determined by each ...method was also compared.
Methods: A cross‐sectional study was performed on 51 eyes in 46 patients presenting to clinical practice for cataract surgery assessment. Preoperative measurement of axial length was performed with applanation ultrasound and the IOLMaster. The IOLMaster measurements were used to determine the intraocular lens power based on the SRK/T formula. Postoperative refractive outcomes were obtained and spherical equivalent calculated and compared to the predicted refractive error with each biometric method.
Results: On average the axial lengths measured by the IOLMaster were longer by 0.15 mm compared to ultrasound biometry (P < 0.01). Using the IOLMaster over applanation ultrasound biometry significantly improved the postoperative refractive outcome from 0.65 D to 0.42 D (P = 0.011).
Conclusions: The IOLMaster provides an accurate axial length measurement and results in accurate intraocular lens power calculation based on the SRK/T formula. It is quick and easy to use and provides a non‐contact technique with no risk of infection or corneal abrasion.
Quantum Hall effect in a wide parabolic well Gusev, G.M; Leite, J.R; Olshanetskii, E.B ...
Physica. B, Condensed matter,
April 2001, 2001-04-00, Letnik:
298, Številka:
1-4
Journal Article
Recenzirano
We examine the activated conductivity for Landau levels at filling factors N=1,2 in a parabolic AlxGa1−xAs well down to 30mK. We assume that the possible mechanism of transport is a hopping ...conductivity in the middle between overlapping levels. These results demonstrate that the plateau at N=1,2 in quantum Hall effect are due to the energy gaps between electric subbands.
The electrical characteristics of the self-assembled quantum dots embbeded in GaAs wells of the GaAs/AlAs superlattices were studied by capacitance spectroscopy and were compared with results ...obtained for the dots embbeded in bulk GaAs. A much stronger electron localization was detected for the quantum dots embedded in the superlattice in comparison with those embedded in bulk GaAs. As a consequence, the electrical characteristics of the structures with quantum dots grown in superlattices were found to be significantly thermo-stabilized. It was shown that these structures present different strengths of the localization of electrons caused by the effective increase of the heights of the barriers when the dots were grown in the superlattices.