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1.
Artigo em Inglês | MEDLINE | ID: mdl-34770229

RESUMO

BACKGROUND: Do gender, age, body mass and height influence eye biometrical properties in young adults? METHODS: A total of 155 eyes (92 female, 63 male) of healthy subjects between the ages of 18 and 39 years were included in the study. The subjects' gender and age were recorded, and their body mass, height and biometrical properties of the eyes were measured. RESULTS: The male subjects had significantly thicker and flatter corneas and lower minimal rim-to-disk ratios than the female subjects did. In both genders, age showed strong, negative correlations with anterior chamber depth and pupil diameter and a positive correlation with lens thickness. We also found significant, negative correlations between body height and mass with keratometry measurements, negative correlations between body height and optic disk rim area and rim volume, and positive correlations between body mass and axial length in both genders. CONCLUSIONS: Biometric eye parameters differ among people. In addition to age and gender, which are usually taken into consideration when interpreting ocular biometry findings, we strongly suggest that body height and mass should be also routinely considered when interpreting eye biometry data, as these factors have an impact on ocular biometry.


Assuntos
Biometria , Cristalino , Adolescente , Adulto , Estatura , Estudos Transversais , Olho/anatomia & histologia , Feminino , Humanos , Masculino , Projetos Piloto , Adulto Jovem
2.
Sensors (Basel) ; 21(21)2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34770715

RESUMO

Iris biometric detection provides contactless authentication, preventing the spread of COVID-19-like contagious diseases. However, these systems are prone to spoofing attacks attempted with the help of contact lenses, replayed video, and print attacks, making them vulnerable and unsafe. This paper proposes the iris liveness detection (ILD) method to mitigate spoofing attacks, taking global-level features of Thepade's sorted block truncation coding (TSBTC) and local-level features of the gray-level co-occurrence matrix (GLCM) of the iris image. Thepade's SBTC extracts global color texture content as features, and GLCM extracts local fine-texture details. The fusion of global and local content presentation may help distinguish between live and non-live iris samples. The fusion of Thepade's SBTC with GLCM features is considered in experimental validations of the proposed method. The features are used to train nine assorted machine learning classifiers, including naïve Bayes (NB), decision tree (J48), support vector machine (SVM), random forest (RF), multilayer perceptron (MLP), and ensembles (SVM + RF + NB, SVM + RF + RT, RF + SVM + MLP, J48 + RF + MLP) for ILD. Accuracy, precision, recall, and F-measure are used to evaluate the performance of the projected ILD variants. The experimentation was carried out on four standard benchmark datasets, and our proposed model showed improved results with the feature fusion approach. The proposed fusion approach gave 99.68% accuracy using the RF + J48 + MLP ensemble of classifiers, immediately followed by the RF algorithm, which gave 95.57%. The better capability of iris liveness detection will improve human-computer interaction and security in the cyber-physical space by improving person validation.


Assuntos
COVID-19 , Teorema de Bayes , Biometria , Humanos , Iris , SARS-CoV-2 , Máquina de Vetores de Suporte
3.
J Refract Surg ; 37(11): 754-758, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34756144

RESUMO

PURPOSE: To compare the accuracy of the Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Kane, and SRK/T formulas for intraocular lens power calculation in patients with high axial myopia. METHODS: In this retrospective study, 175 eyes (175 patients) that underwent uneventful cataract surgery were enrolled. According to the axial length (AL), the eyes were divided into long AL (26 ⩽ AL < 28 mm), super long AL (28 ⩽ AL < 30 mm), and extremely long AL (⩾ 30 mm). The mean absolute prediction errors (MAE) 3 months postoperatively and the percentage of eyes within different prediction error were compared, followed by subgroup analysis. RESULTS: The MAE and percentage of eyes within ±0.50 diopters (D) of the five formulas were as follows: Barrett Universal II (0.342, 74.9%), EVO 2.0 (0.314, 82.3%), Haigis (0.336, 74.9%), Kane (0.318, 78.9%), and SRK/T (0.398, 69.7%) (P = .552 and .071, respectively). Although no significant difference was found among the five formulas in the super and extremely long AL groups (P = .792 and .227, respectively), the EVO 2.0 formula achieved the highest accuracy (88.9%, 72 of 81) in the long AL group (P = .049). Moreover, the accuracy of the EVO 2.0 and Haigis formulas was stable, regardless of AL. The SRK/T formula showed a negative trend in the long and super long AL groups, whereas the Barrett Universal II, Kane, and SRK/T formulas showed positive trends in the extremely long AL group. CONCLUSIONS: Overall, the EVO 2.0 and Kane formulas achieved better results in patients with high axial myopia, whereas the other three formulas showed slightly poor outcomes. [J Refract Surg. 2021;37(11):754-758.].


Assuntos
Lentes Intraoculares , Miopia , Facoemulsificação , Biometria , Humanos , Implante de Lente Intraocular , Miopia/cirurgia , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos
4.
Vestn Oftalmol ; 137(5): 14-21, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34726853

RESUMO

Purpose - to comparatively analyze the wavefront aberrations and biometric parameters of the eyes with various degrees of myopia. MATERIAL AND METHODS: The study included 134 eyes of 67 patients with mild, moderate and high myopia aged 7-28 (mean age 19.3±1.5 years). The following biometric parameters were examined: anterior chamber depth (ACD), lens thickness (LT), axial length (AL), as well as corneal and total aberrations. The parameters were studied on the Galilei G6 system (Ziemer Ophthalmic Systems AG, Switzerland) and the OPD-Scan III aberrometer (Nidek, Japan). Spherical aberration (SA) was estimated as the sum of Z4+Z8+Z12. RESULTS: As the refraction increased, the root mean square higher-order aberrations (RMS HOA) also increased significantly: from 0.24±0.02 µm in mild myopia to 0.45±0.03 µm in high myopia, and in eyes with AL of ≥27.0 mm - to 0.57±0.02 µm (p=0.01). An increase in vertical tilt, vertical coma and vertical trefoil were also observed. Total SA was positive and increased in eyes with moderate myopia compared to those with low myopia (from 0.02±0.01 µm to 0.06±0.02 µm, p=0.02), which coincided with changes in the internal optics of the eye: an increase in ACD and a decrease in LT. At the same time, no differences in corneal aberrations were observed among patients with low and moderate myopia. A significant decrease of SA occurred in high myopia (from 0.06 µm in low myopia to 0.015±0.02 µm in high myopia). The average value of SA was 0.005±0.01 µm in eyes with AL of ≥27.0 mm and appeared to be negative in 40% of cases. The average value of corneal SA was negative (-0.002±0.01µm) in eyes with AL of ≥27.0 mm. This group had predominantly patients with congenital myopia. CONCLUSION: An increase of total positive SA in patients with moderate myopia compared to those with low myopia is associated with changes in the internal optics of the eye (ACD, LT). Significant increase of higher-order aberrations and decrease of SA with the transition to negative values was observed in patients with high axial myopia.


Assuntos
Miopia , Adolescente , Adulto , Biometria , Córnea/diagnóstico por imagem , Topografia da Córnea , Humanos , Miopia/diagnóstico , Refração Ocular , Testes Visuais , Acuidade Visual , Adulto Jovem
5.
Yonsei Med J ; 62(12): 1117-1124, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34816642

RESUMO

PURPOSE: To evaluate the accuracy of the Kane formula for intraocular lens (IOL) power calculation in comparison with existing formulas by incorporating optional variables into calculation. MATERIALS AND METHODS: This retrospective review consisted of 78 eyes of patients who had undergone uneventful phacoemulsification with intraocular implantation at Severance Hospital in Seoul, Korea between February 2020 and January 2021. The Kane formula was compared with six of the existing IOL formulas (SRK/T, Hoffer-Q, Haigis, Holladay1, Holladay2, Barrett Universal II) based on the mean absolute error (MAE), median absolute error (MedAE), and the percentages of eyes within prediction errors of ±0.25D, ±0.50D, and ±1.00D. RESULTS: The Barrett Universal II formula demonstrated the lowest MAEs (0.26±0.17D), MedAEs (0.28D), and percentage of eyes within prediction errors of ±0.25D, ± 0.50D, and ±1.00D, although there was no statistically significant difference between Barrett Universal II-SRK/T (p=0.06), and Barrett Universal II-Kane formula (p<0.51). Following the Barrett Universal II formula, the Kane formula demonstrated the second most accurate formula with MAEs (0.30±0.19D) and MedAEs (0.28D). However, no statistical difference was shown between Kane-Barrett Universal II (p=0.51) and Kane-SRK/T (p=0.14). CONCLUSION: Although slightly better refractory outcome was noted in the Barrett Universal II formula, the performance of the Kane formula in refractive prediction was comparable in IOL power calculation, marking its superiority over many conventional IOL formulas, such as HofferQ, Haigis, Holladay1, and Holladay2.


Assuntos
Lentes Intraoculares , Facoemulsificação , Biometria , Humanos , Implante de Lente Intraocular , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos
6.
J Cataract Refract Surg ; 47(11): 1423-1429, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34675149

RESUMO

PURPOSE: To investigate the accuracy of intraocular lens (IOL) formulas for the prediction of postoperative refraction in lens subluxation in Marfan syndrome. SETTING: Eye and ENT Hospital of Fudan University, Shanghai, China. DESIGN: Consecutive retrospective clinical observational case series. METHODS: 60 eligible eyes with lens subluxation from 39 young patients with Marfan syndrome (8.53 ± 4.38 years) underwent phacoemulsification combined with single-eyelet modified capsular tension ring (MCTR) and IOL implantation. The prediction error values with mean zero out (relative prediction error) and their absolute values (AE) were calculated. RESULTS: Generally, the SRK/T formula with Wang-Koch (WK) adjustment had the lowest median AE at 0.418 diopters (D), and the Holladay 1 with WK adjustment had the lowest mean AE at 0.499 D. The median AE of the other 10 formulas, in order from lowest to highest, were Haigis with WK (0.494 D), Holladay 1 with WK (0.495 D), Hoffer Q with WK (0.508 D), Haigis (0.525 D), T2 (0.542 D), Hoffer Q (0.624 D), SRK/T and Holladay 1 (0.660 D), Super (0.680 D), and Barrett Universal II (0.714 D) formulas. Haigis formula was found to be statistically significantly different from SRK/T, Holladay 1, and Barrett Universal II (all 3 P < .001) but not Hoffer Q (P = .236) formula. CONCLUSIONS: The Haigis formula was recommended for young Marfan lens subluxation patients with in-the-bag IOLs and scleral-sutured single-eyelet MCTR implantation. WK adjustments were successful in those cases where the axial length was longer than 25.0 mm.


Assuntos
Subluxação do Cristalino , Lentes Intraoculares , Síndrome de Marfan , Facoemulsificação , Biometria , Criança , Pré-Escolar , China , Humanos , Implante de Lente Intraocular , Síndrome de Marfan/complicações , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos
7.
Niger J Clin Pract ; 24(10): 1551-1557, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34657025

RESUMO

Aim: To assess and compare ophthalmologic and morphologic outcomes between school-age children born moderate-to-late preterm and those born at term. Patients and Methods: Fifty children born moderate-to-late preterm (gestational age 32 weeks + 0 days to 36 + 6 days, age range 5-10 years) at a tertiary university hospital were age- and sex-matched to full-term controls. Visual acuity, refractive errors, ocular biometry, macular, and optic nerve assessments with optical coherence tomography were investigated and compared between cases and controls. Results: No differences in visual acuity or refraction were detected between the study groups. The difference in refractive error was not significant between the groups. Marked differences were observed in the anterior chamber depth, which was shallower in the preterm group (P = 0.044); however, no difference in total axial length was observed. The preterm and control groups significantly differed in terms of central macular thickness (247 ± 19 µm versus 235 ± 22 µm; P = 0.005 right eye); however, the groups did not significantly differ in foveal thickness. Central subfield thickness was also markedly greater in the preterm than in the control children (246.89 ± 19.1 µm versus 236.12 ± 23.3 µm, P = 0.015). No significant differences in mean parafoveal/perifoveal thicknesses or optic nerve parameters were observed between both groups. Conclusion: Significant differences between moderate to late preterm and full-term groups in regards to anterior chamber depth, central macular thickness, and central subfield thickness were found. It is important to recognize that being born preterm might have an impact on some ocular structures. Larger population-based studies should be conducted to study the long-term sequelae of moderate-to-late prematurity in our children.


Assuntos
Retinopatia da Prematuridade , Biometria , Criança , Pré-Escolar , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Retinopatia da Prematuridade/epidemiologia , Arábia Saudita/epidemiologia , Tomografia de Coerência Óptica , Acuidade Visual
8.
J Refract Surg ; 37(10): 686-692, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34661471

RESUMO

PURPOSE: To evaluate the accuracy of total corneal power calculation from a swept-source optical coherence tomography-based biometer and a rotating Scheimpflug tomographer for the Acrysof IQ Panoptix toric TFNT intraocular lens (IOL) (Alcon Labroatories, Inc). METHODS: A retrospective study was undertaken on 145 eyes implanted with the TFNT IOL. The accuracy of total corneal power calculation from a SS-OCT-based biometer (IOLMaster 700; Carl Zeiss Meditec AG; total keratometry [TK]) and a rotating Scheimpflug tomographer (Oculus Optikgeräte GmbH; total corneal refractive power at 3 mm [TCRP3] and at 4 mm [TCRP4]) were compared. The surgically induced astigmatism vector, difference vector, angle of vector, correction index, index of success, coefficient of adjustment, and flattening index were analyzed using the VectrAK analysis program (ASSORT). RESULTS: The index of success showed a significant difference between the three methods (P = .035, analysis of variance test). The mean ± standard deviation of the index of success was the best in TK (0.43 ± 0.20), followed by TCRP4 (0.47 ± 0.24, P = .400, Bonferroni HSD test) and TCRP3 (0.50 ± 0.22, P = .030, Bonferroni HSD test). The preoperative refractive astigmatism prediction error was within ±0.50 diopters (D) in 62 eyes (42.8%) when using TCRP4 and in 66 eyes (45.5%) when using TK. CONCLUSIONS: These study results suggest that the refractive accuracy of TFNT implantation using total corneal power from TCRP4 and TK was favorable. [J Refract Surg. 2021;37(10):686-692.].


Assuntos
Implante de Lente Intraocular , Facoemulsificação , Biometria , Topografia da Córnea , Humanos , Refração Ocular , Estudos Retrospectivos , Tomografia de Coerência Óptica
9.
J Refract Surg ; 37(10): 680-685, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34661474

RESUMO

PURPOSE: To compare the accuracy of the Kane, Hill-RBF 2.0, Barrett Universal II (BUII), and Emmetropia Verifying Optical (EVO) formulas in calculating intraocular lens power in extremely myopic eyes. METHODS: A total of 1,054 highly myopic eyes were included and divided into three groups according to axial length: control (⩾ 26 to < 28 mm), long (⩾ 28 to < 30 mm), and extreme axial length (⩾ 30 mm) groups. Prediction accuracies of the four formulas were compared and factors influencing the refractive errors were evaluated. RESULTS: The Hill-RBF 2.0 formula generated the largest percentage of eyes with refractive errors within ±0.50 and ±1.00 D (71.44% and 94.59%, respectively, compared to 63.38% and 92.31% for the Kane, 61.76% and 94.02% for the BUII, and 59.01% and 87.57% for the EVO formulas; P < .001). The mean absolute errors of the Kane, Hill-RBF 2.0, BUII, and EVO formulas were 0.46 ± 0.38, 0.40 ± 0.39, 0.44 ± 0.30, and 0.58 ± 0.68 D (P < .001). In the long axial length group, the Hill-RBF 2.0 formula had the smallest MAE (all P < .001), whereas the extreme axial length group only had a smaller MAE than the Kane and EVO formulas (both P < .001). The accuracy of the Kane and Hill-RBF 2.0 formulas was affected by corneal curvature and A-constant; the accuracy of the BUII and EVO formulas was affected by corneal curvature, axial length, and A-constant. CONCLUSIONS: The Hill-RBF 2.0 formula outperformed all three other formulas in eyes with axial lengths ⩾ 28 to < 30 mm, and outperformed the Kane and EVO formulas in eyes with axial lengths of 30 mm or greater. [J Refract Surg. 2021;37(10):680-685.].


Assuntos
Lentes Intraoculares , Miopia , Biometria , Emetropia , Humanos , Refração Ocular
10.
BMC Ophthalmol ; 21(1): 364, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645396

RESUMO

BACKGROUND: To evaluate the effects of pretreatment for dry eye disease (DED) on the accuracy of intraocular lens (IOL) power calculation. METHODS: Patients who underwent uneventful cataract surgery were included in the study. IOL power was determined using the SRK/T and Barrett Universal II (Barrett) formulas. The patients were divided into non-pretreatment and pretreatment groups, and those in the pretreatment group were treated with topical 0.5% loteprednol etabonate and 0.05% cyclosporin A for 2 weeks prior to cataract surgery. Ocular biometry was performed in all groups within 2 days before surgery. The mean prediction error, mean absolute error (MAE), and proportions of refractive surprise were compared between the non-pretreatment and pretreatment groups at 1 month postoperatively. Refractive surprise was defined as MAE ≥ 0.75D. RESULTS: In a total of 105 patients, 52 (52 eyes) were in the non-pretreatment group and 53 (53 eyes) in the pretreatment group. The MAE was 0.42 ± 0.33, 0.38 ± 0.34 (SRK/T, Barrett) and 0.23 ± 0.19, 0.24 ± 0.19 in the non-pretreatment and pretreatment groups, respectively (p < 0.001/=0.008). The number of refractive surprises was also significantly lower in the pretreatment group. [non-pretreatment/pretreatment: 9/2 (SRK/T); 8/1 (Barrett); p = 0.024/0.016]. Pretreatment of DED was related to a reduction in postoperative refractive surprise. [SRK/T/Barrett: OR = 0.18/0.17 (95% CI: 0.05-0.71/0.05-0.60), p = 0.014/0.006]. CONCLUSIONS: The accuracy of IOL power prediction can be increased by actively treating DED prior to cataract surgery.


Assuntos
Síndromes do Olho Seco , Lentes Intraoculares , Facoemulsificação , Biometria , Humanos , Implante de Lente Intraocular , Óptica e Fotônica , Refração Ocular , Estudos Retrospectivos
11.
Sensors (Basel) ; 21(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34640975

RESUMO

BACKGROUND: Biometric sensing is a security method for protecting information and property. State-of-the-art biometric traits are behavioral and physiological in nature. However, they are vulnerable to tampering and forgery. METHODS: The proposed approach uses blood flow sounds in the carotid artery as a source of biometric information. A handheld sensing device and an associated desktop application were built. Between 80 and 160 carotid recordings of 11 s in length were acquired from seven individuals each. Wavelet-based signal analysis was performed to assess the potential for biometric applications. RESULTS: The acquired signals per individual proved to be consistent within one carotid sound recording and between multiple recordings spaced by several weeks. The averaged continuous wavelet transform spectra for all cardiac cycles of one recording showed specific spectral characteristics in the time-frequency domain, allowing for the discrimination of individuals, which could potentially serve as an individual fingerprint of the carotid sound. This is also supported by the quantitative analysis consisting of a small convolutional neural network, which was able to differentiate between different users with over 95% accuracy. CONCLUSION: The proposed approach and processing pipeline appeared promising for the discrimination of individuals. The biometrical recognition could clinically be used to obtain and highlight differences from a previously established personalized audio profile and subsequently could provide information on the source of the deviation as well as on its effects on the individual's health. The limited number of individuals and recordings require a study in a larger population along with an investigation of the long-term spectral stability of carotid sounds to assess its potential as a biometric marker. Nevertheless, the approach opens the perspective for automatic feature extraction and classification.


Assuntos
Algoritmos , Identificação Biométrica , Auscultação , Biometria , Artéria Carótida Primitiva , Humanos
12.
BMC Ophthalmol ; 21(1): 374, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686183

RESUMO

AIM: To study the influence of media opacity due to cataract on the development of axial length in paediatric patients from North-East India, using optical biometry. METHOD: This is a prospective, observational study, including consecutive patients attending the paediatric ophthalmology clinic, over a period of 1 year. Patients with other ocular and systemic diseases, unfit for optical biometry measurements due to dense cataract, nystagmus and strabismus were excluded and rest divided into three groups after proper age matching - 1. Group A (Bilateral cataract) 2. Group B (Unilateral cataract) 3. Group C (Bilateral normal). The axial length of the various groups was analysed using independent sample test (for bilateral cataract group) and paired t-test (for unilateral cataract group). Linear regression analysis between age and axial length was done. RESULTS: A total of 177 patients were included.80 cases in Group A (bilateral cataract), 18 cases in Group B (unilateral cataract) and 79 in Group C (bilateral normal) The mean age of the patients in all the groups was 8.88 ± 3.51 years (range: 1-17 years). The bivariate analysis and simple linear regression revealed a statistically significant correlation between age and AL in case of cataractous eyes. (Pearson's coefficient: 0.341, p < 0.001). The mean AL was significantly longer (p = 0.013) in the cataractous eyes (mean = 23.38 ± 2.08 mm) of Group A(bilateral cataract) in the 7-12 years age group as compared to the bilaterally normal eyes (mean AL = 22.57 ± 0.70 mm) of patients in the same age group in Group C. The mean AL of cataractous eyes in group B (unilateral cataract) (mean = 22.46 ± 1.73 mm) as compared to the fellow normal eyes, (mean = 21.87 ± 0.97 mm) was not statistically significant. CONCLUSION: Cataractous eyes have an abnormal axial length development. The influence of media opacity due to cataract on development of axial length in paediatric eyes in the North-East Indian population is variable, in line with global data on the same. Although there is some influence of media opacity, the exact nature is not clearly understood and may have a crucial interaction with genetic and other environmental factors. Genetic testing integrated with biometric analysis is recommended for further understanding of the ocular growth and development.


Assuntos
Extração de Catarata , Catarata , Adolescente , Biometria , Catarata/diagnóstico , Criança , Pré-Escolar , Seguimentos , Humanos , Lactente , Estudos Prospectivos
13.
Comput Intell Neurosci ; 2021: 3110416, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691168

RESUMO

Surveillance remains an important research area, and it has many applications. Smart surveillance requires a high level of accuracy even when persons are uncooperative. Gait Recognition is the study of recognizing people by the way they walk even when they are unwilling to cooperate. It is another form of a behavioral biometric system in which unique attributes of an individual's gait are analyzed to determine their identity. On the other hand, one of the big limitations of the gait recognition system is uncooperative environments in which both gallery and probe sets are made under different and unknown walking conditions. In order to tackle this problem, we propose a deep learning-based method that is trained on individuals with the normal walking condition, and to deal with an uncooperative environment and recognize the individual with any dynamic walking conditions, a cycle consistent generative adversarial network is used. This method translates a GEI disturbed from different covariate factors to a normal GEI. It works like unsupervised learning, and during its training, a GEI disrupts from different covariate factors of each individual and acts as a source domain while the normal walking conditions of individuals are our target domain to which translation is required. The cycle consistent GANs automatically find an individual pair with the help of the Cycle Loss function and generate the required GEI, which is tested by the CNN model to predict the person ID. The proposed system is evaluated over a publicly available data set named CASIA-B, and it achieved excellent results. Moreover, this system can be implemented in sensitive areas, like banks, seminar halls (events), airports, embassies, shopping malls, police stations, military areas, and other public service areas for security purposes.


Assuntos
Processamento de Imagem Assistida por Computador , Reconhecimento Automatizado de Padrão , Biometria , Marcha , Humanos , Caminhada
14.
Ethiop J Health Sci ; 31(4): 823-830, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34703182

RESUMO

Background: The objective of the study was to report on the main parameters of ocular biometry and Intraocular lens (IOL)power of patients attending a cataract surgical campaign in Eastern Ethiopia. Methods: The study was a cross-sectional study on 765 eyes which were eligible for cataract surgery during a mass cataract surgical campaign conducted from April 04 to April 10, 2018 at Bisidimo Hospital, Eastern Ethiopia. Ocular biometric parameters were measured by automated keratorefractometer and Sonomed A-Scan (Model 300AP) using contact applanation method. Multiple linear regression analysis was done to determine association of ocular biometry components with socio demography of the study subjects. Results: The mean corneal curvature and anterior chamber depth (ACD, measured from corneal epithelium to lens) were found to be 7.61 mm and 2.88mm respectively. The mean axial length was estimated to be 22.98 mm. The mean refractive power of IOL was calculated to be 19.34D. The mean axial length in females was shorter than that of males by 0.24 (P - value = 0.01). The mean ACD in males was also larger than that of females by 0.1 (P - value = 0.001). Conclusion: This study provided a larger population based normative data on ocular biometry in Ethiopia. The female sex was a strong predictor of small axial length. Increasing age had no effect on axial length but was found to be a stronger predictor of shallow ACD.


Assuntos
Biometria , Catarata , Estudos Transversais , Etiópia/epidemiologia , Olho , Feminino , Humanos , Masculino , Refração Ocular
15.
Indian J Ophthalmol ; 69(11): 3190-3193, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34708770

RESUMO

Purpose: To calculate the intraocular lens power and to determine the relationship between ocular biometry and severity of diabetic retinopathy (DR) in patients with type II diabetes mellitus. Methods: The study group included 150 type II diabetic subjects with DR. The control group consisted of 150 type II diabetic subjects having no DR. Axial length (AL), corneal power, and anterior chamber depth were measured using LenStar. DR and diabetic macular edema were classified according to International DR Classification. Crystalline lens power was calculated using Barrett Universal II formula. AL to corneal radius ratio was calculated. Chi-square test was used for categorical variables. Results: In multivariate logistic models adjusting for age, sex, glycosylated hemoglobin, duration of diabetes, Mean age of patients in the study group was 62.45 ± 4.85 years, whereas in the control group, it was 63.37 ± 7.29 years. Of the eyes with DR, 117, 76, 69, and 38 had mild NPDR, moderate NPDR, severe NPDR, and PDR, respectively. The difference in the mean duration of diabetes mellitus and glycosylated hemoglobin in both study and control groups was found to be statistically significant. A progressive decrease in the mean AL and the anterior chamber depth was observed with increasing severity of DR, and difference was statistically significant. There was a progressive increase in intraocular lens power with increasing severity of DR, and difference was found to be statistically significant. Conclusion: In persons with diabetes mellitus, globe elongation plays quite an important role in protective effects against DR, with contribution from intraocular lens power and other refractive components.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Lentes Intraoculares , Edema Macular , Idoso , Biometria , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/complicações , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Humanos , Pessoa de Meia-Idade
16.
PLoS One ; 16(10): e0258761, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34665825

RESUMO

Knowledge of both the genetic diversity and geographical distribution of animal genetic resources is a prerequisite for their sustainable utilization, improvement and conservation. The present study was undertaken to explore the current morphological variability within the sheep population in Benin as a prelude for their molecular characterization. From November 2018 to February 2020, 25 quantitative linear body measurements and 5 qualitative physical traits were recorded on 1240 adult ewes from the 10 phytogeographic zones that comprise the three vegetation zones of Benin. Fourteen morphological indices were calculated based on the linear body measurements. The collected data were first analyzed using multiple comparisons of least-square means (LSmeans), followed by generalized linear model (GLM) procedures, to explore the relationships among the measured morphometric traits and the 10 phytogeographic zones. Next, the presence of any genetic sub-populations was examined using multivariate analytical methods, including canonical discriminant analysis (CDA) and ascending hierarchical clustering (AHC). Univariate analyses indicated that all quantitative linear body measurements varied significantly (P<0.05) across the phytogeographic zones. The highest values (LSmean± standard error) of withers height (68.3±0.47 cm), sternum height (46.0±0.35 cm), and rump height (68.8±0.47 cm) were recorded in the Mekrou-Pendjari zone, the drier phytogeographic zone in the North, whereas the lowest values, 49.2±0.34, 25.9±0.26, and 52.0±0.35 cm, respectively, were recorded in the Pobe zone in the South. Multivariate analyses revealed the prevalence of four distinct sheep sub-populations in Benin. The sub-population from the South could be assimilated to the short-legged and that from the North to the West African long-legged sheep. The two other sub-populations were intermediate and closer to the crossbreeds or another short-legged sub-breed. The proportion of individuals correctly classified in their group of origin was approximately 74%. These results uncovered a spatial morphological variation in the Beninese sheep population along a South-North phytogeographic gradient.


Assuntos
Ovinos/anatomia & histologia , Ovinos/classificação , Animais , Benin , Biometria , Demografia , Análise Discriminante , Hibridização Genética , Modelos Lineares , Análise Multivariada , Fenótipo , Filogenia
17.
PLoS One ; 16(10): e0258634, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669758

RESUMO

OBJECTIVE: To investigate whether fetuses with accelerated third trimester growth velocity are at increased risk of shoulder dystocia, even when they are not large-for-gestational-age (LGA; estimated fetal weight (EFW) >95th centile). METHODS: Fetal growth velocity and birth outcome data were prospectively collected from 347 nulliparous women. Each had blinded ultrasound biometry performed at 28 and 36 weeks' gestation. Change in EFW and abdominal circumference (AC) centiles between 28-36 weeks were calculated, standardised over exactly eight weeks. We examined the odds of shoulder dystocia with increasing EFW and AC growth velocities among women with 36-week EFW ≤95th centile (non-LGA), who went on to have a vaginal birth. We then examined the relative risk (RR) of shoulder dystocia in cases of accelerated EFW and AC growth velocities (>30 centiles gained). Finally, we compared the predictive performances of accelerated fetal growth velocities to 36-week EFW >95th centile for shoulder dystocia among the cohort planned for vaginal birth. RESULTS: Of the 226 participants who had EFW ≤95th centile at 36-week ultrasound and birthed vaginally, six (2.7%) had shoulder dystocia. For each one centile increase in EFW between 28-36 weeks, the odds of shoulder dystocia increased by 8% (odds ratio (OR [95% Confidence Interval (CI)]) = 1.08 [1.04-1.12], p<0.001). For each one centile increase in AC between 28-36 weeks, the odds of shoulder dystocia increased by 9% (OR[95%CI] = 1.09 [1.05-1.12], p<0.001). When compared to the rest of the cohort with normal growth velocity, accelerated EFW and AC velocities were associated with increased relative risks of shoulder dystocia (RR[95%CI] = 7.3 [1.9-20.6], p = 0.03 and 4.8 [1.7-9.4], p = 0.02 respectively). Accelerated EFW or AC velocities predicted shoulder dystocia with higher sensitivity and positive predictive value than 36-week EFW >95th centile. CONCLUSIONS: Accelerated fetal growth velocities between 28-36 weeks' gestation are associated with increased risk of shoulder dystocia, and may predict shoulder dystocia risk better than the commonly used threshold of 36-week EFW >95th centile.


Assuntos
Macrossomia Fetal/diagnóstico por imagem , Distocia do Ombro/epidemiologia , Adulto , Biometria , Feminino , Desenvolvimento Fetal , Macrossomia Fetal/complicações , Peso Fetal , Idade Gestacional , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Distocia do Ombro/etiologia , Ultrassonografia Pré-Natal , Circunferência da Cintura
18.
PLoS One ; 16(9): e0257654, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550998

RESUMO

AIMS: To compare the biometric data from partial coherence interferometry (PCI) and swept-source OCT (SS-OCT) in patients with age-related cataract and epiretinal membrane (ERM): ERM, ERM with foveoschisis and macular pseudohole. METHODS: 49 eyes of 49 subjects including 36 ERM, 9 ERM foveoschisis and 4 macular pseudohole were analysed to evaluate the axial length (AL) measurements and the presence of AL measurement errors, defined basing on the shape of the biometric output graphs and on the concordance of AL values between instruments. Eyes with ERM were divided in four stages according to OCT features (i.e. presence/absence of the foveal pit, presence of ectopic inner foveal layers, disrupted retinal layers). RESULTS: The devices provided similar mean AL measurements in all subgroups, with differences <0.1 mm in 41/49 cases (83.6%). AL measurement errors were observed in ERM stages 3 and 4, characterized by ectopic inner foveal layers, and were significantly more frequent with the PCI (8/17, 47%) as compared with the SS-OCT device (2/17, 12%), p = 0.02. The refractive prediction error in cases with AL measurement errors was significantly greater using the PCI compared to the SS-OCT device (p<0.05). CONCLUSION: Both devices provide reliable biometric data in the majority of patients and can be used in the preoperative assessment of patients with age-related cataract and ERM. In eyes with ectopic inner foveal layers, attention should be paid as AL measurement and refractive prediction errors may occur, more frequently with the PCI device.


Assuntos
Biometria , Catarata , Membrana Epirretiniana
19.
Sensors (Basel) ; 21(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34577245

RESUMO

Wireless medical sensor networks (WMSNs) are used in remote medical service environments to provide patients with convenient healthcare services. In a WMSN environment, patients wear a device that collects their health information and transmits the information via a gateway. Then, doctors make a diagnosis regarding the patient, utilizing the health information. However, this information can be vulnerable to various security attacks because the information is exchanged via an insecure channel. Therefore, a secure authentication scheme is necessary for WMSNs. In 2021, Masud et al. proposed a lightweight and anonymity-preserving user authentication scheme for healthcare environments. We discover that Masud et al.'s scheme is insecure against offline password guessing, user impersonation, and privileged insider attacks. Furthermore, we find that Masud et al.'s scheme cannot ensure user anonymity. To address the security vulnerabilities of Masud et al.'s scheme, we propose a three-factor-based mutual authentication scheme with a physical unclonable function (PUF). The proposed scheme is secure against various security attacks and provides anonymity, perfect forward secrecy, and mutual authentication utilizing biometrics and PUF. To prove the security features of our scheme, we analyze the scheme using informal analysis, Burrows-Abadi-Needham (BAN) logic, the Real-or-Random (RoR) model, and Automated Verification of Internet Security Protocols and Applications (AVISPA) simulation. Furthermore, we estimate our scheme's security features, computation costs, communication costs, and energy consumption compared with the other related schemes. Consequently, we demonstrate that our scheme is suitable for WMSNs.


Assuntos
Segurança Computacional , Telemedicina , Biometria , Simulação por Computador , Confidencialidade , Humanos
20.
Sensors (Basel) ; 21(18)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34577370

RESUMO

The large number of Internet-of-Things (IoT) devices that need interaction between smart devices and consumers makes security critical to an IoT environment. Biometrics offers an interesting window of opportunity to improve the usability and security of IoT and can play a significant role in securing a wide range of emerging IoT devices to address security challenges. The purpose of this review is to provide a comprehensive survey on the current biometrics research in IoT security, especially focusing on two important aspects, authentication and encryption. Regarding authentication, contemporary biometric-based authentication systems for IoT are discussed and classified based on different biometric traits and the number of biometric traits employed in the system. As for encryption, biometric-cryptographic systems, which integrate biometrics with cryptography and take advantage of both to provide enhanced security for IoT, are thoroughly reviewed and discussed. Moreover, challenges arising from applying biometrics to IoT and potential solutions are identified and analyzed. With an insight into the state-of-the-art research in biometrics for IoT security, this review paper helps advance the study in the field and assists researchers in gaining a good understanding of forward-looking issues and future research directions.


Assuntos
Identificação Biométrica , Internet das Coisas , Biometria , Segurança Computacional
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