Wavefront aberrations in children with different types of amblyopia

The Eye ◽  
2020 ◽  
Vol 22 (129) ◽  
pp. 14-20
Author(s):  
Ekaterina Naumova ◽  
Elena Titarenko
Keyword(s):  
High Efficiency ◽  
Previous History ◽  
Higher Order ◽  
Control Group ◽  
Higher Order Aberrations ◽  
Unsuccessful Treatment ◽  
Different Types ◽  
Function Analyzer ◽  
Positive Treatment ◽  
Pre Treatment

Purpose. To quantify and characterize higher-order aberrations in eyes of children with amblyopia caused by different etiology factors; to evaluate the relationship between the wavefront profile and the effectiveness of the amblyopia treatment. Material and methods. This study involved 26 children (52 eyes) from 3 to 9 years old (average age 6.2±3 years) with different types of amblyopia: unilateral amblyopia due to impaired binocular vision and anisometropia, as well as unilateral or bilateral amblyopia caused by hyperopia. Patients were divided into four groups depending on the effectiveness of pleoptic treatment: 14 children (24 eyes) – with positive treatment results, 8 children (12 eyes) – with refractory amblyopia, 4 pre-treatment newly diagnosed patients (6 eyes) without previous history of optical correction, and 10 non-amblyopic contralateral eyes (control group). All patients had central fixation and didn`t have any severe systemic diseases. Higher-order aberrations were measured with iTrace Visual Function Analyzer (Tracey Technologies, Houston, TX) after instillation of 1% cyclopentolate eyedrops. Results and discussion. Wavefront profiles were significantly different in the studied groups. Total spherical aberrations and astigmatism were significantly higher in group with refractory amblyopia (-0.53±1.19 and 2.25±1.07, p=0.02) compared with all the other groups: the group of patients before pleoptic treatment (-0.17±0.23 and 1.79±1.47), group treated with high efficiency (-0.31±0.81 and 1.04±0.13) and with control group (-0.13±0.17 and 1.38±0.11). Total coma-like aberrations didn`t show statistically significant differences in all studied groups (р=0.06). The level of corneal higher-order aberrations (total, coma, spherical) in all three amblyopic groups was higher than in the control group without amblyopia. Conclusion. We revealed statistically significant differences in the wavefront profiles in children with amblyopia of various etiologies in comparison with the control group, including higher-order aberrations. The data obtained indicate that an amblyopic eye with hyperopia has higher level of spherical aberrations and astigmatism due to higher level of internal HOAs, particularly spherical aberrations and astigmatism, which is typical for patients with unsuccessful treatment. Therefore, that type of aberrations is likely to be the main cause of refractory amblyopia.

Changes in Higher Order Aberrations after Wavefront-Guided Prk for Correction of Low to Moderate Myopia and Myopic Astigmatism: Two-Year Follow-Up

2007 ◽  
Vol 17 (4) ◽  
pp. 507-514 ◽  
Author(s):  
D. Wygledowska-Promienska ◽  
I. Zawojska
Keyword(s):  
Visual Acuity ◽  
Excimer Laser ◽  
Spherical Aberration ◽  
Higher Order ◽  
Control Group ◽  
Higher Order Aberrations ◽  
Order Root ◽  
Group 2 ◽  
Myopic Astigmatism ◽  
Group 1

Purpose To assess efficacy, safety, and changes in higher order aberrations after wavefront-guided photorefractive keratectomy (PRK) in comparison with conventional PRK for low to moderate myopia with myopic astigmatism using a WASCA Workstation with the MEL 70 G-Scan excimer laser. Methods A total of 126 myopic or myopic-astigmatic eyes of 112 patients were included in this retrospective study. Patients were divided into two groups: Group 1, the study group; and Group 2, the control group. Group 1 consisted of 78 eyes treated with wavefront-guided PRK. Group 2 consisted of 48 eyes treated with spherocylindrical conventional PRK. Results Two years postoperatively, in Group 1, 5% of eyes achieved an uncorrected visual acuity (UCVA) of 0.05; 69% achieved a UCVA of 0.00; 18% of eyes experienced enhanced visual acuity of −0.18 and 8% of −0.30. In Group 2, 8% of eyes achieved a UCVA of 0.1; 25% achieved a UCVA of 0.05; and 67% achieved a UCVA of 0.00 according to logMAR calculation method. Total higher-order root-mean square increased by a factor 1.18 for Group 1 and 1.6 for Group 2. There was a significant increase of coma by a factor 1.74 in Group 2 and spherical aberration by a factor 2.09 in Group 1 and 3.56 in Group 2. Conclusions The data support the safety and effectiveness of the wavefront-guided PRK using a WASCA Workstation for correction of low to moderate refractive errors. This method reduced the number of higher order aberrations induced by excimer laser surgery and improved uncorrected and spectacle-corrected visual acuity when compared to conventional PRK.

scholarly journals Abnormal higher order aberrations in anisometropic amblyopia

2020 ◽  
Author(s):  
Lingyi Zhang ◽  
Meng Liao ◽  
Wenqiu Zhang ◽  
Longqian Liu
Keyword(s):  
Visual Acuity ◽  
Pearson Correlation ◽  
Higher Order ◽  
Control Group ◽  
Third Order ◽  
Higher Order Aberrations ◽  
Regular Treatment ◽  
Anisometropic Amblyopia ◽  
Pearson Correlation Test ◽  
Order Root

Abstract Background The study compared ocular higher-order aberrations (HOAs) between monocular anisometropic amblyopia children and similar anisometropia children with normal best-corrected visual acuity (BCVA). The amblyopia eyes could not reach the standard BCVA level of their age even after several months' regular treatment of amblyopia. We tried to find if these intractable amblyopia eyes have abnormal HOAs. Methods Fifty school-aged children (5–9 years) with hyperopic anisometropia were recruited at West China hospital clinic. Each subject shall be reexamined once every three months, four consecutive reexaminations for 12 months, of which only 25 subjects with normal BCVA after wearing glasses shall be included in the control group. The rest 25 subjects were treated by glasses and six months’ patching. Their interocular difference of visual acuity was still more than or equal to LogMAR 0.2, and the eyes with poor visual acuity did not reach the normal level in the twelfth month. These subjects were included in the amblyopia group. The BCVA, HOAs (5 mm pupil diameter), and axial length were recorded for all subjects. Results There were significant differences of higher order aberrations in C (3, -3) between the amblyopia eyes and the other three groups of eyes with normal BCVA (all p < 0.05). There were significant differences of higher-order aberrations in third-order root-mean-square aberrations(RMS) between the amblyopia eyes and the low-diopter eyes from two subject groups(both p < 0.05). Compared to high-diopter eyes in the control group, there were a significantly higher C(3,-3) in all amblyopia eyes and a significantly higher third-order RMS (p = 0.040) in the moderate-to-severe amblyopia group. In the Pearson correlation test, the C(3,-3) and third order RMS demonstrated statistically significant correlations with BCVA ( (r=-0.19, p = 0.04; r = 0.37, p < 0.01). Conclusions The anisometropic amblyopia eyes had different HOAs from the eyes with normal visual acuity. The third-order aberrations were the primary abnormal higher-order aberration in amblyopia eyes.

scholarly journals Potential and Risk of the Visible Light Assisted Photocatalytical Treatment of PRD1 and T4 Bacteriophage Mixtures

2020 ◽  
Vol 24 (3) ◽  
pp. 215-224
Author(s):  
Sandra Sakalauskaite ◽  
Neringa Kuliesiene ◽  
Deimante Galalyte ◽  
Simona Tuckute ◽  
Marius Urbonavicius ◽  
...  
Keyword(s):  
Visible Light ◽  
High Efficiency ◽  
Uv Light ◽  
Control Group ◽  
Treatment Efficiency ◽  
Untreated Control Group ◽  
Photocatalytic Inactivation ◽  
Different Types ◽  
T4 Bacteriophage ◽  
Self Repair

AbstractIn current study UV light and visible light activated photocatalytic inactivation treatment was applied to the less commonly studied subjects, namely bacteriophages PRD1, T4 and their mixture. By using UV light irradiation and high efficiency P25 TiO2 photocatalyst powders it was demonstrated that individually and in mixture PRD1 bacteriophage is particularly vulnerable to the photocatalytic inactivation and in just approximately 20 min its infectivity is reduced by 100 %. As for the T4 bacteriophage, it has been reported that under UV irradiation T4 triggers self-repair and replication mechanisms therefore under same photocatalytic inactivation conditions infectivity reduction reaches just 60 %. Surprisingly, by studying visible light photocatalytic treatment efficiency of PRD1 and T4 bacteriophage mixture we identified that T4 bacteriophage potentially triggers the same self-repair and replication mechanism as it does under UV light. Moreover, by using two different types of visible light activated photocatalysts we determined that when efficiency of the used photocatalyst is too small the overall infectivity of the T4 bacteriophage can significantly surpass the corresponding property of the untreated control group.

scholarly journals Influence of Overhanging Bleb on Corneal Higher-Order Aberrations after Trabeculectomy

2021 ◽  
Vol 11 (1) ◽  
pp. 177
Author(s):  
Yu Mizuno ◽  
Kazuyuki Hirooka ◽  
Yoshiaki Kiuchi
Keyword(s):  
Mitomycin C ◽  
Pupil Diameter ◽  
Glaucoma Surgery ◽  
Higher Order ◽  
Control Group ◽  
Higher Order Aberrations ◽  
Ocular Surgery ◽  
Conjunctival Flap ◽  
Single Center Study ◽  
History Of

Recent advances in ocular aberrometry have revealed that ocular surgery increases ocular and corneal higher-order aberrations. This retrospective single-center study aimed to examine the effects of the overhanging bleb on corneal higher-order aberrations using a wavefront analyzer. We included 61 eyes from 50 patients with overhanging bleb after trabeculectomy with a fornix-based conjunctival flap using mitomycin C (overhanging bleb group) and 65 eyes from 54 glaucoma patients with no history of glaucoma surgery (control group). Corneal higher-order aberrations (total higher-order aberrations, coma aberrations, coma-like aberrations, spherical aberrations, and spherical-like aberrations) on a 4 mm pupil diameter were measured using the TOPCON KR-1W wavefront analyzer. Corneal coma aberrations were higher in the overhanging bleb group than in the control group (0.16 ± 0.13 μm and 0.10 ± 0.05 μm, respectively; p = 0.042). Corneal coma-like aberrations were also higher in the overhanging bleb group than in the control group (0.31 ± 0.32 μm and 0.16 ± 0.09 μm, respectively; p = 0.022). With an increasing ratio of cornea covered by the bleb to the entire cornea, all corneal higher-order aberrations increased except for corneal coma-like aberrations. Overhanging bleb after trabeculectomy with a fornix-based conjunctival flap using mitomycin C and its size influenced corneal higher-order aberrations.

scholarly journals Monochromatic higher order aberrations in highly myopic eyes with Staphyloma

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Santiago Delgado-Tirado ◽  
Alberto López-Miguel ◽  
Yazmin Báez-Peralta ◽  
Lucía González-Buendía ◽  
Itziar Fernández ◽  
...  
Keyword(s):  
High Myopia ◽  
Spherical Aberration ◽  
Higher Order ◽  
Posterior Pole ◽  
Intraocular Lenses ◽  
Analysis Of Covariance ◽  
Control Group ◽  
Higher Order Aberrations ◽  
Posterior Staphyloma ◽  
Clinical Counselling

Abstract Background Prevalence of high myopia is continuously increasing, thus, patients affected with staphyloma are abundant worldwide. Assessment of the quality of vision in these patients is mandatory for a proper clinical counselling, specially when undergoing surgical procedures that require intraocular lenses implantation. Thus, the purpose of the study was to assess monochromatic higher order aberrations (HOAs) in highly myopic eyes with staphyloma with or without a dome-shaped macula. Methods Participants underwent spectral-domain optical coherence tomography, ocular axial biometry, dual Scheimpflug photography and integrated Placido disk topography, and Hartmann-Shack wavefront analysis. Five groups were evaluated: a low-moderate myopia control group (< 6.00 diopters, n = 31) and four high myopia (≥6.00 diopters) groups: eyes without staphyloma (n = 18), eyes with inferior staphyloma (n = 14), eyes with posterior staphyloma without dome-shaped macula (n = 15) and eyes with posterior staphyloma with dome-shaped macula (n = 17). Subsequently, two new groups (including all participants) were created to assess differences between myopia with and without staphyloma. One-way analysis of covariance was performed using age and lens densitometry as covariates. Results Statistically significant (p ≤ 0.05) differences in anterior corneal fourth-order HOAs were observed between the low-moderate myopia and no-dome-shaped macula (Mean: 0.16 μm) and dome-shaped macula posterior staphyloma groups (Mean: 0.12 μm) in younger patients (≤45 years old). The same groups also showed (p ≤ 0.05) significant differences for anterior corneal primary spherical aberration (Mean: 0.19 and 0.13 μm, respectively). In addition, anterior corneal tetrafoil was significantly higher (p = 0.04) in dome-shaped macula compared to no-dome-shaped macula (Mean: 0.18 vs 0.06 μm, respectively). When all participants were grouped together, significantly lower mean anterior corneal primary spherical aberration (0.15 μm vs. 0.27 μm, p = 0.004) and higher internal primary spherical aberration (0.04 μm vs. -0.06 μm, p = 0.04) was observed in staphyloma compared to no-staphyloma myopic patients. Conclusions Eyes with high myopia and staphyloma have less positive anterior corneal primary spherical aberration and less negative internal primary spherical aberration, suggesting that the anterior corneal surface tends to mimic in a specular fashion the posterior pole profile. This corneal behaviour appears to change in patients older than 45 years.

Bioethanol production from thermochemically pre-treated olive mill solid residues using the yeast Pachysolen tannophylus

2013 ◽  
Vol 14 (2) ◽  
pp. 118-124 ◽  
Keyword(s):  
Olive Oil ◽  
Ethanol Yield ◽  
Solid Residue ◽  
Residual Oil ◽  
Edible Fungi ◽  
Pachysolen Tannophilus ◽  
Three Phase ◽  
Different Types ◽  
Pre Treatment ◽  
Olive Mill

Olive oil mill solid residue (OMSR) is the solid waste generated during olive oil production process in three-phase olive mills. It consists of the remaining pulp of olive processing after the extraction of oil, as well as the cracked seeds of the olive fruits, containing thus mainly lignocellulose and residual oil. The commonly used practice for OMSR management is combustion, after having extracted the residual oil by secondary extraction using organic solvents. Other proposed ways of OMSR management are their exploitation as substrate for edible fungi production and compost, and as feedstock for biofuels generation such as methane and bioethanol. In the latter case, the complex carbohydrates (cellulose and hemicellulose) of the lignocellulose of OMSR have to be degraded towards their simple sugars and further fermented via microorganisms. The purpose of the present study was to investigate the effect of thermochemical pre-treatment of OMSR, on the final ethanol yield from the yeast Pachysolen tannophilus. Nine different types of OMSR-based substrates were tested i.e. raw OMSR, hydrolysates generated from pretreated OMSR with NaOH (0.5 %, 1.5 % w/v) and H2SO4 (0.5 %, 1.5 % v/v), and pretreated OMSR with NaOH (0.5 %, 1.5 % w/v) and H2SO4 (0.5 %, 1.5 % v/v) whole biomass. It was shown that in all cases pretreatment enhanced the consumption of carbohydrates as well as ethanol final yields.

Ocular higher-order aberrations in patients with various refractive errors

2017 ◽  
Vol 21 (3) ◽  
pp. 177-183
Author(s):  
Eman Morad ◽  
Mohamed Abd_ Elateef ◽  
Mohammad Mousa ◽  
Ismael Abdelatif
Keyword(s):  
Higher Order ◽  
Refractive Errors ◽  
Higher Order Aberrations

Research on the methods and means of action strength training in aerobics training

2021 ◽  
pp. 002072092110042
Author(s):  
Xiaona Yang ◽  
Yang Ji ◽  
Da Ke ◽  
Fang Li
Keyword(s):  
Strength Training ◽  
Team Member ◽  
High Efficiency ◽  
Colleges And Universities ◽  
The Body ◽  
Energy Output ◽  
Control Group ◽  
Experimental Sample ◽  
Training Method ◽  
Core Strength

Aerobics is a beautiful and rhythmic sport. In recent years, aerobics has developed rapidly, and has become one of the essential courses of physical education in Colleges and universities. But the existing aerobics courses in Colleges and universities are less involved in the training process of action strength. Lack of strength quality is a common shortcoming of Aerobics Athletes in Colleges and universities. Therefore, this paper puts forward the methods and means of action strength training in aerobics training. According to the characteristics of competitive aerobics, combined with the traditional training strategy of action strength, this paper formulates the method of action strength training suitable for College Aerobics athletes. In order to further verify the effectiveness of this method, this paper takes a university aerobics team as an experimental sample to carry out a comparative analysis of the effect of action strength training. Relevant studies have proved that core strength training has the following effects on aerobics players: 1. Helps the calisthenics team member stabilize the trunk, improve the body's control ability and balance ability. 2. It is conducive to completing difficult movements of calisthenics with high efficiency and low energy consumption. 3. Helps the aerobics team member to enhance the special strength. 4. It can effectively prevent sports injuries. 5. It can improve the direction change and displacement speed of the body. 6. It can improve the energy output of the core strength to the limbs and other muscle groups during movement, so that the movement can be completed more perfectly.According to the results of the experiment, the explosive force and endurance of the experimental group after 8 weeks of training have been significantly improved, and formed a more obvious difference with the control group. The aerobics training method developed in this paper can be divided into two stages: the initial stage and the middle stage, which can better meet the students with different physical qualities. At the end of this paper, a fast strength training method is introduced, and the characteristics of different training methods are analyzed.

scholarly journals The Effect of Different Types of Internal Curing Liquid on the Properties of Alkali-Activated Slag (AAS) Mortar

2021 ◽  
Vol 13 (4) ◽  
pp. 2407
Author(s):  
Guang-Zhu Zhang ◽  
Xiao-Yong Wang ◽  
Tae-Wan Kim ◽  
Jong-Yeon Lim ◽  
Yi Han
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Deionized Water ◽  
Internal Curing ◽  
Control Group ◽  
Alkali Activated Slag ◽  
Different Types ◽  
Naoh Solution ◽  
Activated Slag ◽  
Alkali Activated

This study shows the effect of different types of internal curing liquid on the properties of alkali-activated slag (AAS) mortar. NaOH solution and deionized water were used as the liquid internal curing agents and zeolite sand was the internal curing agent that replaced the standard sand at 15% and 30%, respectively. Experiments on the mechanical properties, hydration kinetics, autogenous shrinkage (AS), internal temperature, internal relative humidity, surface electrical resistivity, ultrasonic pulse velocity (UPV), and setting time were performed. The conclusions are as follows: (1) the setting times of AAS mortars with internal curing by water were longer than those of internal curing by NaOH solution. (2) NaOH solution more effectively reduces the AS of AAS mortars than water when used as an internal curing liquid. (3) The cumulative heat of the AAS mortar when using water for internal curing is substantially reduced compared to the control group. (4) For the AAS mortars with NaOH solution as an internal curing liquid, compared with the control specimen, the compressive strength results are increased. However, a decrease in compressive strength values occurs when water is used as an internal curing liquid in the AAS mortar. (5) The UPV decreases as the content of zeolite sand that replaces the standard sand increases. (6) When internal curing is carried out with water as the internal curing liquid, the surface resistivity values of the AAS mortar are higher than when the alkali solution is used as the internal curing liquid. To sum up, both NaOH and deionized water are effective as internal curing liquids, but the NaOH solution shows a better performance in terms of reducing shrinkage and improving mechanical properties than deionized water.

scholarly journals Variational Problems with Time Delay and Higher-Order Distributed-Order Fractional Derivatives with Arbitrary Kernels

Mathematics ◽  
2021 ◽  
Vol 9 (14) ◽  
pp. 1665
Author(s):  
Fátima Cruz ◽  
Ricardo Almeida ◽  
Natália Martins
Keyword(s):  
Time Delay ◽  
Fractional Derivatives ◽  
Variational Problems ◽  
Higher Order ◽  
Sufficient Optimality Conditions ◽  
Fractional Operator ◽  
Different Types ◽  
Generalized Fractional Derivatives ◽  
Necessary And Sufficient ◽  
Distributed Order

In this work, we study variational problems with time delay and higher-order distributed-order fractional derivatives dealing with a new fractional operator. This fractional derivative combines two known operators: distributed-order derivatives and derivatives with respect to another function. The main results of this paper are necessary and sufficient optimality conditions for different types of variational problems. Since we are dealing with generalized fractional derivatives, from this work, some well-known results can be obtained as particular cases.

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