scholarly journals Evaluation of Corneal Higher- Order Aberrations in Adults with Different Refractive Status: تقييم الزّوغانات القرنيّة عالية التّرتيب عند البالغين في مختلف الحالات الانكساريّة

Author(s):  
Omar Khaled Yaseer, Taym Darwish, Najwa Kurdogly Omar Khaled Yaseer, Taym Darwish, Najwa Kurdogly

Purpose: The aim of this study is to evaluate the root mean square error (RMS) of corneal higher- order aberrations in Syrian adult population in different refractive status (emmetropia, myopia, hyperopia and simple myopic astigmatism). Methods: This cross- sectional study was conducted at Tishreen University Hospital in Latakia, Syrian Arab Republic. A total of 420 patients (840 eyes), ages 18- 40 years, participated in the study. Refraction was measured with an autorefractor keratometer and expressed as a spherical equivalent. Total corneal higher- order aberrations (Coma, Spherical Aberration, Trefoil) were measured using Sirius Corneal Topography at a pupil diameter of 5 mm. Results: RMS of Coma and Spherical aberrations peaked in the hyperopia group (0.18 ± 0.08, 0.11 ± 0.02) respectively. Whereas, Trefoil was higher in the severe myopia and simple myopic astigmatism groups (0.25 ± 0.05, 0.25 ± 0.08) respectively. Conclusions: Among a Syrian population, some types of refractive status were associated with certain types of higher- order aberrations, with a significant increase in trefoil in severe myopia and simple myopic astigmatism.

Healthcare ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1643
Author(s):  
Chia-Yi Lee ◽  
Wei-Chi Wu ◽  
Ling Yeung ◽  
Hung-Chi Chen ◽  
Kuan-Jen Chen ◽  
...  

We aim to evaluate magnitudes of higher order aberrations (HOAs) from 3rd-6th order after scleral buckling (SB) for rhegmatogenous retinal detachment (RRD). A retrospective cross-sectional study of 19 patients with RRD who received SB (six receiving encircling SB, thirteen receiving segmental SB) was conducted. A wavefront analysis for surveying HOAs and other ophthalmic parameters were collected. Data between operated and fellow eyes, and a subgroup analysis of operated eyes, were analyzed by the Mann–Whitney U test, while a generalized linear model was applied to evaluate the correlation of HOAs to best-corrected visual acuity (BCVA) and optical symptoms. BCVA in the operated eyes was significantly worse (LogMAR: 0.18 ± 0.23 versus 0.05 ± 0.07, p = 0.001). Tilt (0.32 ± 0.14 versus 0.13 ± 0.08, p = 0.004), defocus (1.78 ± 0.47 versus 1.05 ± 0.17, p = 0.019) and coma (0.43 ± 0.11 versus 0.27 ± 0.09, p = 0.016) were significantly increased after SB. All root mean square (RMS), including RMS-3, RMS-4 and total RMS, were higher in operated eyes (all p < 0.05). Regarding Zernike terms, a significant elevation of vertical coma in the operated eyes was found (p = 0.038). In addition, tilt (0.41 ± 0.10 versus 0.17 ± 0.12, p = 0.007), defocus (2.27 ± 0.58 versus 0.82 ± 0.39, p = 0.001) and coma (0.59 ± 0.17 versus 0.11 ± 0.10, p = 0.015) were higher in the segmental subgroup, whereas spherical aberration (SA) was higher in the encircling subgroup (0.22 ± 0.04 versus 0.40 ± 0.15, p = 0.024) and RMS-4 and total RMS were increased in the segmental subgroup (both p < 0.05). Besides, tilt was correlated to worse BCVA (p = 0.036), whereas all four HOAs were correlated to the presence of optical symptoms (all p < 0.05). In conclusion, SB may increase HOAs, which could be associated with unfavorable postoperative visual outcomes and subject symptoms.


2007 ◽  
Vol 17 (4) ◽  
pp. 507-514 ◽  
Author(s):  
D. Wygledowska-Promienska ◽  
I. Zawojska

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.


2020 ◽  
Vol 8 (14) ◽  
pp. 850-850 ◽  
Author(s):  
Jiaqing Zhang ◽  
Guangming Jin ◽  
Ling Jin ◽  
Xiaoting Ruan ◽  
Xiaoxun Gu ◽  
...  

2021 ◽  
Author(s):  
Xuan Liao ◽  
Mei-Jie Wang ◽  
Qing-Qing Tan ◽  
Chang-Jun Lan

Abstract Purpose To evaluate the repeatability of wavefront aberration measurements and the correlation between corneal aberration and pupil size in normal eyes using a wavefront-based autorefractor (i.ProfilerPlus; Carl Zeiss Vision, Germany). Methods A prospective cross-sectional study. Wavefront aberrations, including SA (Z40), coma (Z3 − 1, Z31), trefoil (Z3 − 3, Z33) and total higher-order aberrations (tHOA), were measured at different pupil diameters. The repeatability was evaluated using one-way ANOVA method, and statistical indicators including within-subject standard deviation (Sw), test-retest repeatability (TRT), and intra-class correlation coefficient (ICC). The correlations between corneal aberrations and pupil sizes were evaluated by Pearson correlation analysis. Results A total of 96 healthy young volunteers were enrolled. Corneal and ocular higher-order aberrations (HOA) measured by i.Profiler showed Sw<0.01µm, TRT < 0.10µm, ICC > 0.90. There was a linear positive correlation between the corneal HOA and pupil size. The correlation coefficient between SA and tHOA was the largest (r = 0.996, P < 0.001). Conclusions The measurements of wavefront aberrations by i.Profiler are highly repeatable. Corneal HOA is significantly dependent on pupil size. SA is the most influential aberration for visual quality.


2016 ◽  
pp. 59-65 ◽  
Author(s):  
Van Mao Nguyen

Background: Lymphoma is one of the most ten common cancers in the world as well as in Vietnam which has been ever increasing. It was divided into 2 main groups Hodgkin and non – Hodgkin lymphoma in which non-Hodgkin lymphoma appeared more frequency, worse prognosis and different therapy. Objectives: - To describe some common characteristics in patients with non – Hodgkin lymphoma; - To determine the proportion between Hodgkin and non- Hodgkin lymphoma, histopathological classification of classical Hodgkin by modified Rye 1966 and non-Hodgkin lymphoma by Working Formulation (WF) of US national oncology institute 1982. Materials and Method: This cross-sectional study was conducted on 65 patients with Hodgkin and non- Hodgkin lymphoma diagnosed definitely by histopathology at Hue Central Hospital and Hue University Hospital. Results:. The ratio of male/female for the non-Hodgkin lymphoma was 1.14/1, the most frequent range of age was 51-60 accounting for 35%, not common under 40 years. Non - Hodgkin lymphoma appeared at lymph node was the most common (51.7%), at the extranodal site was rather high 48.3%. The non - Hodgkin lymphoma proportion was predominant 92.3% comparing to the Hodgkin lymphoma only 7.7%; The most WF type was WF7 (53.3%), following the WF6 18,3% and WF5 11,7%; The intermediate malignancy grade of non- Hodgkin lymphoma was the highest proportion accouting for 85%, then the low and the high one 8.3% and 6.7% respectively. Conclusion: The histopathological classification and the malignant grade of lymphoma for Hodgkin and non - Hodgkin lymphoma played a practical role for the prognosis and the treatment orientation, also a fundamental one for the modern classification of non - Hodgkin lymphoma nowadays. Key words: lymphoma, Hodgkin lymphoma, non-Hodgkin lymphoma, classication, grade, histopathology, lymph node


2020 ◽  
Vol 20 (5) ◽  
pp. 748-751
Author(s):  
Seyed Ali Dehghan Manshadi ◽  
Neda Alijani ◽  
Mohammadreza Salehi ◽  
Omid Dadras ◽  
SeyedAhmad SeyedAlinaghi ◽  
...  

Introduction: The aim of this study was to determine the prevalence of exposure to hepatitis A by means of serologic markers in chronic hepatitis B patients, with the secondary aim of finding the best prevention method for hepatitis A infection in susceptible groups of our setting. Methods: During the period between 2016 and 2017, we recruited 403 hepatitis B patients aged more than 14 years and regularly attending the infectious diseases clinic at a referral university hospital, Tehran, Iran. A blood sample was collected from all the patients and tested for hepatitis A IgG. The data was analyzed by SPSS v.19. Results: Although none of the patients had previously received hepatitis A vaccine, the results for serologic level of hepatitis A IgG, demonstrated positive results in 379 (94%) cases. The mean age of patients with negative and positive IgG was 29.17 and 42.46 years, respectively; the difference was statistically significant (P≤0.001). The majority of seronegative patients were young adults aged < 25 years and 25 to 35 years (P <0.001). Conclusion: Seroprevalence of hepatitis A in chronic HBV patients in Iran is high. As HBV infected patients younger than 35 years could be seronagative for HAV infection, evaluation of these patients for HAV infection and vaccination of seronegative patients would be a reasonable approach.


2019 ◽  
Vol 19 (6) ◽  
pp. 803-808 ◽  
Author(s):  
Luigi Vimercati ◽  
Luigi De Maria ◽  
Francesca Mansi ◽  
Antonio Caputi ◽  
Giovanni M. Ferri ◽  
...  

Background: Thyroid diseases occur more frequently in people exposed to ionizing radiation, but the relationship between occupational exposure to ionizing radiation and thyroid pathologies still remains unclear. Objective: To evaluate the prevalence of thyroid diseases in healthcare workers exposed to low-level ionizing radiation compared with a control group working at the University Hospital of Bari, Southern Italy, and living in the same geographical area, characterized by mild iodine deficiency. Methods: We ran a cross-sectional study to investigate whether healthcare workers exposed to ionizing radiation had a higher prevalence of thyroid diseases. Four hundred and forty-four exposed healthcare workers (241 more exposed, or “A Category”, and 203 less exposed, or “B Category”) and 614 nonexposed healthcare workers were enrolled during a routine examination at the Occupational Health Unit. They were asked to fill in an anamnestic questionnaire and undergo a physical examination, serum determination of fT3, fT4 and TSH, anti-TPO ab and anti-TG ab and ultrasound neck scan. Thyroid nodules were submitted to fine needle aspiration biopsy when indicated. Results: The prevalence of thyroid diseases was statistically higher in the exposed workers compared to controls (40% vs 29%, adPR 1.65; IC95% 1.34-2.07). In particular, the thyroid nodularity prevalence in the exposed group was approximately twice as high as that in the controls (29% vs 13%; adPR 2.83; IC95% 2.12-3.8). No statistically significant association was found between exposure to ionizing radiation and other thyroid diseases. Conclusion: In our study, mild ionizing radiation-exposed healthcare workers had a statistically higher prevalence of thyroid diseases than the control group. The results are likely due to a closer and more meticulous health surveillance programme carried out in the ionising radiation-exposed workers, allowing them to identify thyroid alterations earlier than non-exposed health staff.


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