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1.
Medicine (Baltimore) ; 98(50): e18026, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852065

RESUMO

The purpose of this study is to evaluate the biometric parameters of crystalline lens components and to find effective factors for predicting postoperative intraocular lens (IOL) position. This retrospective study included 97 eyes from 97 patients with a mean age of 63.00 ± 12.38 (SD) years. The biometric measurements were performed by means of a 3-dimensional optical coherence tomography (3D-OCT) device. Specifically, anterior chamber depth (ACD), aqueous depth (AD), lens thickness (LT), lens meridian parameter (LMP), white-to-white diameters (WTW), anterior segment length (ASL), the anterior part of lens (aLT), and the posterior part of lens (pLT) were measured. Additionally, axial length (AL) and corneal radius (CR) were measured by the partial coherence interferometry. Ninety-seven eyes were divided into thin lens group (LT < 4.5 mm) and thick lens group (LT ≥ 4.5 mm). The differences between the above two groups were also analyzed. Postoperative IOL position was measured by 3D-OCT at 3 months postoperatively and regression formulas for predicting postoperative IOL position were developed by various combinations of preoperative factors. As lens thickened, ACD and AD became shallow (all P < .001). AD, ACD, ASL, aLT, and pLT showed statistically significant differences between two subgroups classified on the basis of LT (all P < .001). Meanwhile, the value obtained by subtracting aLT from pLT did not show any association with the other biometric measurements. The combination of ACD, aLT, pLT, AL, CR, and WTW showed the highest correlation with postoperative IOL position (R = 0.536, P < .001). In conclusion, pLT-aLT was an independent factor not affected by any other variables and did not show significant difference between thin lens group and thick lens group. The subdivision of the lens structure using 3D-OCT helps to predict postoperative IOL position.


Assuntos
Segmento Anterior do Olho/diagnóstico por imagem , Biometria/métodos , Extração de Catarata/métodos , Terapia a Laser/métodos , Lentes Intraoculares , Tomografia de Coerência Óptica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Cristalino/diagnóstico por imagem , Cristalino/cirurgia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Retrospectivos
2.
Ophthalmic Physiol Opt ; 39(6): 451-458, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31696541

RESUMO

PURPOSE: To determine the differences in mean ocular dimensions between urban and rural children and identify possible influencing factors. METHODS: This work uses previously published data from the Shandong Children Eye Study, which was based on a random cluster sampling applied to a cross-sectional school-based study design in the rural Guanxian County and Weihai city. All children underwent auto-refractometry and biometry under cycloplegia. RESULTS: The study included 3290 children (aged 9.35 ± 2.93 years), consisting of 888 pairs of boys and 757 pairs of girls matched by sex, age and refractive error (each pair matching one child from urban cohort with one from the rural cohort). Overall urban children were significantly taller and heavier than rural children (t-test; p < 0.001), which was confirmed for all age groups for weight. Urban ocular axial lengths were significantly longer by 0.23 mm compared to the rural population (t-test; p < 0.001), mostly in younger children and boys. Meanwhile, corneal curvatures were flatter in the urban cohort by 0.08 mm (p < 0.001). This association of axial length with urban vs rural region was reduced in magnitude by 69.7% after accounting for height. CONCLUSIONS: For the same, matched refractive error, children from urban regions had significantly longer eyes and flatter corneal curvature than rural children. Since corneal curvature is defined during the first 2 years of life, early environmental factors may be the source of these differences in ocular dimensions.


Assuntos
Biometria/métodos , Córnea/fisiopatologia , Refração Ocular/fisiologia , Erros de Refração/diagnóstico , População Rural , População Urbana , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Córnea/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Erros de Refração/epidemiologia , Erros de Refração/fisiopatologia
3.
Cochrane Database Syst Rev ; 9: CD012544, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31476798

RESUMO

BACKGROUND: Gestational diabetes mellitus (GDM) is a common medical condition that complicates pregnancy and causes adverse maternal and fetal outcomes. At present, most treatment strategies focus on normalisation of maternal blood glucose values with use of diet, lifestyle modification, exercise, oral anti-hyperglycaemics and insulin. This has been shown to reduce the incidence of adverse outcomes, such as birth trauma and macrosomia. However, this involves intensive monitoring and treatment of all women with GDM. We propose that using medical imaging to identify pregnancies displaying signs of being affected by GDM could help to target management, allowing low-risk women to be spared excessive intervention, and facilitating better resource allocation. OBJECTIVES: We wanted to address the following question: in women with gestational diabetes, does the use of fetal imaging plus maternal blood glucose concentration to indicate the need for medical management compared with glucose concentration alone reduce the risk of adverse perinatal outcomes? SEARCH METHODS: We searched Cochrane Pregnancy and Childbirth's Trials Register (29 January 2019), ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP) (both on 29 January 2019), and reference lists of retrieved studies. SELECTION CRITERIA: Randomised controlled trials, including those published in abstract form only. Studies using a cluster-randomised design and quasi-randomised controlled trials were both eligible for inclusion, but we didn't identify any. Cross-over trials were not eligible for inclusion in our review.We included women carrying singleton pregnancies who were diagnosed with GDM, as defined by the trials' authors. The intervention of interest was the use of fetal biometry on imaging methods in addition to maternal glycaemic values for indicating the use of medical therapy for GDM. The control group was the use of maternal glycaemic values alone for indicating the use of such therapy. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors extracted data and checked them for accuracy. MAIN RESULTS: Three randomised controlled trials met the inclusion criteria for our systematic review - the studies randomised a total of 524 women.We assessed the three included studies as being at a low to moderate risk of bias; the nature of the intervention made it difficult to achieve blinding of participants and personnel and none of the trial reports contained information about methods of allocation concealment (and were therefore assessed as being at an unclear risk of selection bias).In all studies, the intervention was the use of fetal biometry on ultrasound to identify fetuses displaying signs of fetal macrosomia, and the use of this information to indicate the use of medical anti-hyperglycaemic treatments. Those pregnancies were subject to more stringent blood glucose targets than those without signs of fetal macrosomia.Maternal outcomesThe use of fetal biometry in addition to maternal blood glucose concentration (compared with maternal blood glucose concentration alone) may make little or no difference to the incidence of caesarean delivery (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.59 to 1.10; 2 trials, 428 women; low-certainty evidence). We are unclear about the results for hypertensive disorders of pregnancy (RR 0.80, 95% CI 0.34 to 1.89; 2 trials, 325 women) due to very low-certainty evidence. The included trials did not report on development of type 2 diabetes in the mother or maternal hypoglycaemia.Fetal and neonatal outcomesThe use of fetal biometry may make little or no difference to the incidence of neonatal hypoglycaemia (RR 0.90, 95% CI 0.57 to 1.42; 3 trials, 524 women; low-certainty evidence). Very low-certainty evidence means that we are unclear about the results for large-for-gestational age (RR 0.81, 95% CI 0.38 to 1.74; 3 trials, 524 women); shoulder dystocia (RR 0.33, 95% CI 0.01 to 7.98; 1 trial, 96 women); a composite measure of perinatal morbidity or mortality (RR 1.00, 95% CI 0.21 to 4.71; 1 study, 96 women); or perinatal mortality (RR 0.33, 95% CI 0.01 to 7.98; 1 trial, 96 women). AUTHORS' CONCLUSIONS: This review is based on evidence from three trials involving 524 women. The trials did not report some important outcomes of interest to this review, and the majority of our secondary outcomes were also unreported. The available evidence ranged from low- to very low-certainty, with downgrading decisions based on limitations in study design, imprecision and inconsistency.There is insufficient evidence to evaluate the use of fetal biometry (in addition to maternal blood glucose concentration values) to assist in guiding the medical management of GDM, on either maternal or perinatal health outcomes, or the associated costs.More research is required, ideally larger randomised studies which report the maternal and infant short- and long-term outcomes listed in this review, as well as those outcomes relating to financial and resource implications.


Assuntos
Biometria/métodos , Diabetes Gestacional/terapia , Macrossomia Fetal/prevenção & controle , Complicações na Gravidez/prevenção & controle , Feminino , Humanos , Insulina/uso terapêutico , Gravidez , Resultado da Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Eur. j. anat ; 23(5): 355-359, sept. 2019. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-183865

RESUMO

The crista terminalis (CT) is a well-defined fibromuscular crest formed by the union of the venous sinus and the primitive right auricle, which extends along the posterolateral face of the right atrial wall. The pectinate muscles (PM) are muscular crests which extend anterolaterally from the CT to the auricle and may present in a series of variable shapes and sizes. The biggest and most prominent PM is called the taenia sagittalis (TS). PM with highly trabeculated muscle fibres predispose patients to the occurrence of arrhythmias. The present article is a descriptive study of the anatomical and biometric characteristics of the right atrium. We studied 30 hearts of adult Chilean individuals, aged between 18 and 84 years, of both sexes, with no apparent cardiac pathology, belonging to the Normal Human Anatomy Unit of the Basic Sciences Department of Universidad de La Frontera. The samples were washed with distilled water and immediately placed in formalin at 10%. The atria were first separated from the ventricles, then opened perpendicularly through the intercaval zone to give access to the interior. The distribution of pectinate muscles found, according to the classification of Loukas et al. (2008) and Siddiqui et al. (2013), was as follows: Type I, 20%; Type II, 23.3%; Type III, 23.3%; Type IV, 6.7%; Type V, 6.7%; Type VI, 20%. TS was found to be present in 46.6% of the hearts examined, two or more TS in 29.8% and no TS in 23.6%. The length of the pectinate muscles is variable; the shortest are located on the medial wall. Six types of pectinate muscle patterns were observed


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Coração/anatomia & histologia , Átrios do Coração/anatomia & histologia , Átrios do Coração/parasitologia , Taenia , Biometria/métodos , Estudos Transversais , Chile
5.
Anim Reprod Sci ; 208: 106113, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31405472

RESUMO

Testicular volume (TV) is one of the most important traits used in evaluation of the reproductive capacity of male animals. The levelled-container used in the present study was found to be reliable instrument to measure TV, based on a water displacement method. Sperm-associated antigen 11 (SPAG11) is an important gene that affects male reproductive performance. An objective of the present study, therefore, was to determine if single nucleotide polymorphisms (SNPs) in a fragment of the SPAG11 gene could be used to determine associations with values of testicular biometric variables in Boer goats. Primers were designed to amplify the full length of the first two exons of SPAG11. The targeted fragment was generated using a molecular cloning technique. As the result, four SNPs, [g.1256A > G(ss19199134542), g.1270C > T(ss19199134541), g.1325A > G(ss19199134540) and g.1327 G > A (ss19199134543)], were detected using a single-base extension (SBE) method. Two of these SNPs were synonymous (ss19199134540 and ss19199134542). The other two SNPs were nonsynonymous, thus, there were changes in amino acid in the resulting protein: threonine to isoleucine (for ss19199134541) and arginine to glutamine (for ss19199134543). The SNP ss19199134543 was the only locus detected that was associated with TV (P = 0.002). None of the testes dimensions nor TW were associated with detected SPAG11 gene SNPs. Most likely, the ss19199134543 locus affects tissue structures adjacent to the testes, causing the change in TV. In conclusion, among the studied testicular biometric variables, TV had the greatest potential for preselecting of bucks with desirable semen quality. The use of the levelled-container as a TV measurement approach was an accurate and reliable method.


Assuntos
Antígenos de Superfície/genética , Biometria/métodos , Glicoproteínas/genética , Cabras , Polimorfismo de Nucleotídeo Único , Testículo/anatomia & histologia , Animais , Biometria/instrumentação , Regulação da Expressão Gênica/fisiologia , Masculino , Testículo/fisiologia
6.
BMC Ophthalmol ; 19(1): 169, 2019 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-31376834

RESUMO

BACKGROUND: Accurate alignment of toric intraocular lens (TIOL) to steep corneal astigmatic axis is important to achieve effective postoperative results. The authors compare the accuracy of astigmatism correction using automated and manual marking in TIOL implantation during cataract surgery. METHODS: One hundred thirty-two eyes with nuclear density from Grade 2 to 4 were randomly subdivided into 2 groups (automated and manual marking). All patients underwent manual marking and the steep axis was compared to SensoMotoric Instruments (SMI). After phacoemulsification, 62 patients underwent toric IOL implantation using the SMI and 70 patients underwent toric IOL implantation using manual marking. Intraoperative measurement was the steep axis difference. Clinical measurements included preoperative and postoperative best corrected visual acuity (BCVA), and TIOL axis. RESULTS: The intraoperative steep axis difference between SMI and manual marking was 7.86 ± 6.4 degrees. The difference between the preoperative steep axis and the postoperative TIOL axis using SMI (3.63 ± 1.12 degrees) was significantly lower than that using manual marking (8.29 ± 2.23 degrees) (P < 0.05). CONCLUSIONS: The steep axis measurements may be different when using SMI vs. manual marking. The SMI is more accurate than manual marking for TIOL implantation during cataract surgery. TRIAL REGISTRATION: Current Controlled Trials ISRCTN12294725 , Retrospectively registered, on 20 July 2018.


Assuntos
Automação/métodos , Catarata/fisiopatologia , Lentes Intraoculares , Cuidados Pré-Operatórios/métodos , Refração Ocular/fisiologia , Acuidade Visual , Biometria/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese
7.
Acta Clin Croat ; 58(1): 87-94, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31363329

RESUMO

The aim of the study was to assess biometric factor aberrations and differences among groups of eyes with cataract and pseudoexfoliative syndrome, cataract and pseudoexfoliative glaucoma, and cataract and primary open-angle glaucoma (POAG), and to determine biometric factors of the eye specific for the group of glaucomatous patients with pseudoexfoliative syndrome by use of optical low-coherence reflectometry. This retrospective study included 72 patients, and the study sample of 102 eyes was divided into the following three groups according to diagnosis: 29 eyes with pseudoexfoliative syndrome and cataract; 36 eyes with POAG and cataract; and 37 eyes with pseudoexfoliative glaucoma and cataract. Data on biometric measurements (central corneal thickness, pupillary diameter, anterior chamber depth, lens thickness, axial length, retinal thickness, astigmatism and white-to-white) obtained by use of optical low-coherence reflectometry on a Lenstar LS 900® (Haag-Streit International) were collected and analyzed by thorough survey of medical documentation of patients scheduled for cataract surgery at Department of Ophthalmology, Sveti Duh University Hospital in Zagreb, Croatia. Comparative analysis of the groups yielded statistically significant differences in central corneal thickness (F2/99=7.066; p=0.001) and lens thickness (F2/96=5.133; p=0.008). The group of eyes diagnosed with pseudoexfoliative glaucoma and cataract had a significantly thinner cornea as compared with the other two groups and a significantly thicker lens as compared with the group of eyes with POAG and cataract. In conclusion, optical low-coherence reflectometry revealed differences in biometric factors among the three groups of eyes, with a statistically significantly thinner cornea and thicker lens in the group of glaucomatous patients with pseudoexfoliative syndrome.


Assuntos
Biometria/métodos , Catarata/diagnóstico , Glaucoma/diagnóstico , Tomografia de Coerência Óptica/métodos , Idoso , Croácia , Técnicas de Diagnóstico Oftalmológico , Feminino , Humanos , Cristalino/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Retina/patologia , Estudos Retrospectivos
8.
Indian J Ophthalmol ; 67(8): 1353-1356, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31332141

RESUMO

A 54-year-old patient presented with cataract, 5 years after undergoing SMILE for high myopia in both eyes. He was motivated in achieving spectacle free vision and his post SMILE-induced aberrations were minimal, due to which he was found suitable for a trifocal IOL implant. Of the various methods considered, the IOL power predicted by a novel combined telecentric keratometry and swept source OCT-based method was finally selected. One month post-operatively, the patient achieved a binocular UDVA of 20/20p and near vision of N.6, suggesting that newer IOL formulae could be superior in providing satisfactory outcomes in post refractive patients.


Assuntos
Substância Própria/cirurgia , Cirurgia da Córnea a Laser/métodos , Implante de Lente Intraocular , Lentes Intraoculares Multifocais , Miopia Degenerativa/cirurgia , Facoemulsificação , Biometria/métodos , Sensibilidades de Contraste/fisiologia , Topografia da Córnea , Humanos , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Período Pós-Operatório , Pseudofacia/fisiopatologia , Visão Binocular/fisiologia , Acuidade Visual/fisiologia
9.
Comput Methods Programs Biomed ; 177: 269-275, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31319955

RESUMO

BACKGROUND AND OBJECTIVE: In this paper, we introduce a new R package goftte for goodness-of-fit assessment based on cumulative sums of model residuals useful for checking key assumptions in the Cox regression and Fine and Gray regression models. METHODS: Monte-Carlo methods are used to approximate the null distribution of cumulative sums of model residuals. To limit the computational burden, the main routines used to approximate the null distributions are implemented in a parallel C++ programming environment. Numerical studies are carried out to evaluate the empirical type I error rates of the different testing procedures. The package and the documentation are available to users from CRAN R repositories. RESULTS: Results from simulation studies suggested that all statistical tests implemented in goftte yielded excellent control of the type I error rate even with modest sample sizes with high censoring rates. CONCLUSIONS: As compared to other R packages goftte provides new useful method for testing functionals, such as Anderson-Darling type test statistics for checking assumptions about proportional (sub-) distribution hazards. Approximations for the null distributions of test statistics have been validated through simulation experiments. Future releases will provide similar tools for checking model assumptions in multiplicative intensity models for recurrent data. The package may help to spread the use of recent advocated goodness-of-fit techniques in semiparametric regression for time-to-event data.


Assuntos
Biometria/métodos , Cirrose Hepática Biliar/diagnóstico , Modelos de Riscos Proporcionais , Software , Algoritmos , Bilirrubina/análise , Simulação por Computador , Bases de Dados Factuais , Humanos , Cirrose Hepática Biliar/sangue , Método de Monte Carlo , Linguagens de Programação , Tempo de Protrombina , Análise de Regressão
10.
Sensors (Basel) ; 19(13)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31266251

RESUMO

Hand pose estimation is a critical technology of computer vision and human-computer interaction. Deep-learning methods require a considerable amount of tagged data. Accordingly, numerous labeled training data are required. This paper aims to generate depth hand images. Given a ground-truth 3D hand pose, the developed method can generate depth hand images. To be specific, a ground truth can be 3D hand poses with the hand structure contained, while the synthesized image has an identical size to that of the training image and a similar visual appearance to the training set. The developed method, inspired by the progress in the generative adversarial network (GAN) and image-style transfer, helps model the latent statistical relationship between the ground-truth hand pose and the corresponding depth hand image. The images synthesized using the developed method are demonstrated to be feasible for enhancing performance. On public hand pose datasets (NYU, MSRA, ICVL), comprehensive experiments prove that the developed method outperforms the existing works.


Assuntos
Biometria/métodos , Mãos/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Interface Usuário-Computador , Algoritmos , Aprendizado Profundo , Mãos/diagnóstico por imagem , Humanos
11.
Sensors (Basel) ; 19(13)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277389

RESUMO

Sensors provide the foundation of many smart applications and cyber-physical systems by measuring and processing information upon which applications can make intelligent decisions or inform their users. Inertial measurement unit (IMU) sensors-and accelerometers and gyroscopes in particular-are readily available on contemporary smartphones and wearable devices. They have been widely adopted in the area of activity recognition, with fall detection and step counting applications being prominent examples in this field. However, these sensors may also incidentally reveal sensitive information in a way that is not easily envisioned upfront by developers. Far worse, the leakage of sensitive information to third parties, such as recommender systems or targeted advertising applications, may cause privacy concerns for unsuspecting end-users. In this paper, we explore the elicitation of age and gender information from gait traces obtained from IMU sensors, and systematically compare different feature engineering and machine learning algorithms, including both traditional and deep learning methods. We describe in detail the prediction methods that our team used in the OU-ISIR Wearable Sensor-based Gait Challenge: Age and Gender (GAG 2019) at the 12th IAPR International Conference on Biometrics. In these two competitions, our team obtained the best solutions amongst all international participants, and this for both the age and gender predictions. Our research shows that it is feasible to predict age and gender with a reasonable accuracy on gait traces of just a few seconds. Furthermore, it illustrates the need to put in place adequate measures in order to mitigate unintended information leakage by abusing sensors as an unanticipated side channel for sensitive information or private traits.


Assuntos
Algoritmos , Biometria/métodos , Marcha/fisiologia , Monitorização Fisiológica/instrumentação , Dispositivos Eletrônicos Vestíveis , Acelerometria/instrumentação , Fatores Etários , Bases de Dados Factuais , Aprendizado Profundo , Feminino , Humanos , Masculino , Cadeias de Markov , Modelos Biológicos , Fatores Sexuais
12.
Sensors (Basel) ; 19(13)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284418

RESUMO

Multimodal systems are a workaround to enhance the robustness and effectiveness of biometric systems. A proper multimodal dataset is of the utmost importance to build such systems. The literature presents some multimodal datasets, although, to the best of our knowledge, there are no previous studies combining face, iris/eye, and vital signals such as the Electrocardiogram (ECG). Moreover, there is no methodology to guide the construction and evaluation of a chimeric dataset. Taking that fact into account, we propose to create a chimeric dataset from three modalities in this work: ECG, eye, and face. Based on the Doddington Zoo criteria, we also propose a generic and systematic protocol imposing constraints for the creation of homogeneous chimeric individuals, which allow us to perform a fair and reproducible benchmark. Moreover, we have proposed a multimodal approach for these modalities based on state-of-the-art deep representations built by convolutional neural networks. We conduct the experiments in the open-world verification mode and on two different scenarios (intra-session and inter-session), using three modalities from two datasets: CYBHi (ECG) and FRGC (eye and face). Our multimodal approach achieves impressive decidability of 7.20 ± 0.18, yielding an almost perfect verification system (i.e., Equal Error Rate (EER) of 0.20% ± 0.06) on the intra-session scenario with unknown data. On the inter-session scenario, we achieve a decidability of 7.78 ± 0.78 and an EER of 0.06% ± 0.06. In summary, these figures represent a gain of over 28% in decidability and a reduction over 11% of the EER on the intra-session scenario for unknown data compared to the best-known unimodal approach. Besides, we achieve an improvement greater than 22% in decidability and an EER reduction over 6% in the inter-session scenario.


Assuntos
Biometria/métodos , Bases de Dados Factuais , Eletrocardiografia , Olho , Face , Processamento de Imagem Assistida por Computador , Olho/anatomia & histologia , Face/anatomia & histologia , Feminino , Humanos , Iris/anatomia & histologia , Masculino , Adulto Jovem
13.
Semin Ophthalmol ; 34(5): 392-397, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257972

RESUMO

Silicone oil (SO) is used mainly when managing complex retinal detachments, commonly with proliferative vitreoretinopathy, as well as a hemostatic agent in proliferative diabetic retinopathy. Combined lens exchange and pars plana vitrectomy remains preferred by many surgeons; however, sequential surgery might be advantageous to minimize the postoperative anterior chamber inflammatory response, particularly in proliferative diabetic retinopathy or retinal detachment. The aim of the study was to evaluate the optimal method of intraocular lens (IOL) calculation in eyes filled with SO. Different techniques are employed for axial length assessment in eyes filled with SO, including preoperative A-scan applanation or immersion biometry, partial coherence interferometry (PCI), or less commonly computed tomography, magnetic resonance imaging, or intraoperative retinoscopy/biometry after SO removal. PCI might provide better refractive outcomes compared to ultrasound measurements, however, the quality of presented evidence is low. Bias in calculation may be a result of limited vitreous base removal during vitrectomy, partial filling of the vitreous chamber with SO and measurements in supine position, macular edema or detachment, selection of an inappropriate IOL calculation formulas and sulcus IOL placement. Clinicians should consider that even when employing optical biometry and correct calculation formulas only a third of eyes filled with silicone oil might achieve ± 1.0 D of target refraction, compared to 97.2% of normal eyes. We would recommend performing optical biometry before the application of SO; if this is impossible, measurement of the second eye or biometry after SO removal is an alternative. Implantation of a convex-plano monofocal polymethyl methacrylate or foldable hydrophobic acrylic IOL with large optic diameter is advised in these patients.


Assuntos
Biometria/métodos , Implante de Lente Intraocular/métodos , Lentes Intraoculares , Erros de Refração/diagnóstico , Descolamento Retiniano/cirurgia , Óleos de Silicone/administração & dosagem , Humanos
14.
Spine (Phila Pa 1976) ; 44(13): E766-E773, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31205169

RESUMO

STUDY DESIGN: Reliability study. OBJECTIVE: To evaluate the applicability and reliability of 9.4T magnetic resonance imaging (MRI) in the assessment of degenerative disc disease compared with 3T MRI. SUMMARY OF BACKGROUND DATA: MRI is a reliable indicator of biochemical changes in the intervertebral disc (IVD) including hydration status, proteoglycan content, and disc degeneration compared with anatomical and histological studies. High-field 9.4T MRI has been shown to provide superior resolution and anatomical detail. However, it has not been tested against current standard MRI techniques. METHODS: Disc degeneration was initiated in 36 skeletally mature ewes 6 months prior to necropsy via validated surgical IVD injury models using either scalpel injury or drill-bit injury techniques at lumbar spine levels L2/3 and L3/4 with L1/2, L4/5, and L5/6 serving as control discs. All ex vivo IVDs were examined with 9.4T MRI and 3T MRI. All scans were analyzed using the Pfirrmann grading system by four independent observers. Intra- and interobserver reliability was assessed using kappa statistics and Spearman correlation. RESULTS: Inter- and intraobserver agreement for 9.4T MRI was excellent, both at κ 0.91 (P < 0.001). Comparatively, 3T interobserver reliability demonstrated substantial agreement at κ 0.61 (P < 0.001). Complete agreement was obtained in 92.7% to 100% of discs at 9.4T compared with 69.7% to 83.1% at 3T. A difference of one grade or more occurred in 6.7% at 9.4T and 39.3% at 3T. 9.4T MRI scored 97.3% of discs as grade 1 to 2 compared with 71.3% at 3T. 3T MRI tended to over-score the extent of disc degeneration with 28.6% of discs scored as grade 3 or higher compared with 2.7% at 9.4T MRI. CONCLUSION: 9.4T MRI study of IVD degeneration using the Pfirrmann grading system demonstrated excellent inter- and intraobserver reliability. Comparatively, 3T MRI demonstrated a tendency to over score the extent of disc degeneration. This improved reliability of 9.4T MRI holds great potential for its clinical applications. LEVEL OF EVIDENCE: 3.


Assuntos
Degeneração do Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Animais , Biometria/métodos , Feminino , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/patologia , Imagem por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Ovinos
15.
J Med Syst ; 43(7): 214, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154541

RESUMO

Today the multimodal biometric system has become a major area of study that is identified with applications of a large size in a recognition system. The feature selection is probably found to be the best factor to be optimized and is an on-going challenge in the midst of the optimization problems in the human recognition system. The feature selection aspires to bring down the number of the features, remove all types of redundant data and noise which result in a very high rate of recognition. The step further effects on the human recognition system and its performance. The work further presents a newer biometric system of verification that was multimodal and based on three different features which are the face, the hand vein, and the ear. This has today emerged as an extensively researched topic which spans various disciplines like signal processing, pattern recognition, and also computer vision. The features have been extracted by making use of the Incremental Principal Component Analysis (IPCA). Further, the work presented another novel algorithm of feature selection which was based on the Multi-Objective Modified Genetic Algorithm (MOM-GA). The Genetic Algorithm (GA) had been modified by means of introducing a levy search as opposed to a process of mutation. The algorithm has also proved to be an effective method of computation in which the search space is found to be highly dimensional. A classifier that makes use of the K-Nearest Neighbour (KNN) for classifying all accurate features is used. There were some investigations that were carried out and these results proved that this MOM-GA feature selection algorithm had been found as that which can generate certain excellent results using a minimal set of chosen features.


Assuntos
Algoritmos , Biometria/métodos , Processamento de Sinais Assistido por Computador , Orelha/anatomia & histologia , Face/anatomia & histologia , Mãos/anatomia & histologia , Mãos/irrigação sanguínea , Humanos , Análise de Componente Principal
16.
Indian J Ophthalmol ; 67(7): 1068-1072, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31238413

RESUMO

Purpose: To prospectively evaluate the biometric changes in Indian pediatric cataract and postoperative refractive status. Methods: A total of 147 patients were recruited into three groups: age <6 months, age between 7 months and 18 months, and age between 19 and 60 months and prospectively observed for 6 months. Exclusion criteria were preterm birth, microphthalmia, microcornea, megalocornea, uveitis, glaucoma, and traumatic or complicated cataract. Axial length and keratometry, the primary outcome measures, were taken preoperatively under general anesthesia before surgery. These children were followed up for 6 months to look for refractive and biometric changes. T-test and linear regression with the logarithm of independent variables were done. Results: All unilateral cataractous eyes (n = 25) and randomly selected bilateral cases (n = 122) were included in the analysis, for a total of 147 eyes. Mean age was 17.163 ± 13.024 months; axial length growth was 0.21, 0.18, 0.06 mm/month, and keratometry decline was 0.083, 0.035, 0.001 D/month in age groups 0-6, 7-18, and 19-60 months, respectively. The visual acuity improved in log MAR from 1.020 to 0.745 at 6 months postoperatively. There was statistically significant (Spearman's correlation coefficient = -0.575, P < 0.001) between age and postoperative refraction. There were no intraocular lens (IOL)-related complications seen in the immediate postoperative period. Peripheral opacification was seen in 102 eyes and central opacification in 1 eye at a 6-month follow-up. Conclusion: Indian eyes have a lower rate of axial length growth and keratometry change in comparison with western eyes implying smaller undercorrection in emmetropic IOL power for Indian pediatric eyes to achieve a moderate amount of hyperopia.


Assuntos
Comprimento Axial do Olho/fisiopatologia , Biometria/métodos , Extração de Catarata/efeitos adversos , Catarata/epidemiologia , Lentes Intraoculares , Refração Ocular/fisiologia , Erros de Refração/fisiopatologia , Pré-Escolar , Feminino , Seguimentos , Humanos , Incidência , Índia/epidemiologia , Lactente , Masculino , Complicações Pós-Operatórias , Estudos Prospectivos , Erros de Refração/epidemiologia , Erros de Refração/etiologia
17.
Graefes Arch Clin Exp Ophthalmol ; 257(9): 2049-2056, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183540

RESUMO

PURPOSE: To determine optical biometry data criteria for the detection of abnormal refraction in preschool children, and to evaluate the accuracy of these criteria for detecting amblyopia refractive risk factor (ARF), as defined in the 2013 guidelines of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS). METHODS: The present study included 200 eyes of 100 preschool children with normal eyes for the experimental determination of criteria and 142 eyes of 71 preschool children for validation of these criteria. Statistical data from normal eyes were used to determine both "high sensitivity failure criterion" and "high specificity failure criterion" associated with corneal astigmatism, interocular difference in axial length, and the prediction interval of a regression formula for predicting corneal power from axial length. Ophthalmological examination of children for validation included testing cycloplegic refraction and optical biometry testing. Outcomes from optical biometry criteria were compared with determination via ophthalmological examination, and the accuracy of the criteria for detecting ARF was evaluated. RESULTS: Sensitivity of the "high sensitivity failure criterion" for detecting 2013 AAPOS ARF was 100%, while the specificity was 80.5%. The sensitivity of the "high specificity failure criterion" was 93.3%, while the specificity was 95.1%. CONCLUSIONS: The criteria derived from optical biometry data in this study exhibited excellent sensitivity and specificity for detecting ARF. This study may lead to a new approach to vision screening in preschool children.


Assuntos
Ambliopia/diagnóstico , Biometria/métodos , Córnea/diagnóstico por imagem , Refração Ocular/fisiologia , Seleção Visual/métodos , Acuidade Visual , Ambliopia/fisiopatologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Reprodutibilidade dos Testes , Fatores de Risco
18.
J Refract Surg ; 35(6): 362-368, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31185101

RESUMO

PURPOSE: To compare the accuracy of intraocular lens (IOL) power calculation based on standard keratometry (K) and the new Total Keratometry (TK). METHODS: A post-hoc analysis of study data based on 145 pseudophakic astigmatic eyes was conducted. The absolute prediction error (APE) of spherical equivalent (SE) and cylinder (CYL) was calculated based on K and TK (including posterior corneal surface) data recorded 6 weeks after IOL implantation. APE was calculated as the difference between the postoperative refraction and the refractive error predicted by three classic IOL calculation methods (Haigis/Haigis-T, Barrett Universal II, Barrett Toric Calculator) and two new formulas developed for TK (Barrett TK Universal II, Barrett TK Toric). For APE in SE, the Haigis-T (K versus TK) and Barrett Universal II (K) versus Barrett TK Universal II (TK) were compared. For APE in CYL, the Haigis-T (K versus TK) and Barrett Toric Calculator (K) versus Barrett TK Toric formula (TK) were compared. RESULTS: Mean APE in SE and CYL was lower based on TK values compared to K, with a mean APE difference (K - TK) of 0.011 ± 0.107 diopters (D) (SE Haigis-T; 95% confidence interval [CI]: -0.004 to infinity), 0.016 ± 0.113 D (SE: Barrett Universal II versus Barrett TK Universal II; 95% CI: 0.0005 to infinity), 0.103 ± 0.173 D (CYL: Haigis-T; 95% CI: 0.0791 to infinity), and 0.020 ± 0.148 D (CYL: Barrett Toric versus Barrett TK Toric; 95% CI: -0.0002 to infinity). APE in SE was within ±0.50 D in 86% (Barrett TK Universal II) versus 84% (Barrett Universal II) of eyes. APE in CYL was within ±0.50 D in 58% (Haigis from TK) versus 44% (Haigis from K) of eyes. CONCLUSIONS: In comparison to standard K, a higher prediction accuracy can be expected by using TK values along with the two newly developed formulas. TK values are compatible with standard IOL power calculation formulas and existing optimized IOL constants. [J Refract Surg. 2019;35(6):362-368.].


Assuntos
Astigmatismo/fisiopatologia , Córnea/fisiopatologia , Lentes Intraoculares , Nomogramas , Óptica e Fotônica , Idoso , Idoso de 80 Anos ou mais , Biometria/métodos , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Facoemulsificação , Estudos Prospectivos , Pseudofacia/fisiopatologia , Refração Ocular/fisiologia , Reprodutibilidade dos Testes , Testes Visuais
19.
Gen Dent ; 67(3): 32-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31199742

RESUMO

The new-patient visit includes examination, diagnosis, and establishment of a treatment plan. This process must include an evaluation of the dental occlusion and stomatognathic system, including the temporomandibular joints. This clinical case describes the use of biometric aids, including T-Scan, BioJVA, and JT-3D, in the digital evaluation of a patient with signs and symptoms of occlusal stress. These technologies provide clinicians with additional information that can help in the examination and diagnostic processes.


Assuntos
Biometria/métodos , Planejamento de Assistência ao Paciente , Radiografia Dentária , Oclusão Dentária , Humanos , Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/diagnóstico
20.
Sensors (Basel) ; 19(12)2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31207911

RESUMO

The term "plenoptic" comes from the Latin words plenus ("full") + optic. The plenoptic function is the 7-dimensional function representing the intensity of the light observed from every position and direction in 3-dimensional space. Thanks to the plenoptic function it is thus possible to define the direction of every ray in the light-field vector function. Imaging systems are rapidly evolving with the emergence of light-field-capturing devices. Consequently, existing image-processing techniques need to be revisited to match the richer information provided. This article explores the use of light fields for face analysis. This field of research is very recent but already includes several works reporting promising results. Such works deal with the main steps of face analysis and include but are not limited to: face recognition; face presentation attack detection; facial soft-biometrics classification; and facial landmark detection. This article aims to review the state of the art on light fields for face analysis, identifying future challenges and possible applications.


Assuntos
Face/anatomia & histologia , Reconhecimento Facial , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Biometria/métodos , Humanos
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