17 resultados para eye Biometric

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Purpose: To investigate the contribution of the individual ocular components, i.e. anterior chamber depth, lens thickness and vitreous chamber depth, to total axial length in patients with esotropic amblyopia. Methods: The study population consisted of 74 children, aged between 5 and 8 years: thirty-seven patients with esotropic amblyopia and 37 healthy volunteers (control group). The participants underwent a comprehensive ophthalmological examination, including cycloplegic refraction and A-scan ultrasonography. Anterior chamber depth, lens thickness, vitreous chamber depth and total axial length were recorded. Paired Student's t-tests were used to compare biometric measurements between amblyopic eyes and their fellow eyes and between right and left eyes in the control group. To evaluate the contribution of the ocular components to the total axial length, we report the individual components as a percentage of total axial length. Results: The comparison between amblyopic and fellow eyes regarding the individual contribution from ocular components to the total axial length revealed greater contribution from lens thickness (P=0.001) and smaller contribution from vitreous chamber depth (P=0.001) in amblyopic eyes, despite similar contribution from anterior chamber depth (P=0.434). The comparison between right and left eyes in the control group showed similar contributions from anterior chamber depth (P=0.620), lens thickness (P=0.721), and vitreous chamber depth (P=0.483). Conclusions: This study shows differences between amblyopic and non-amblyopic eyes when the total axial length is broken down into the individual contribution from the ocular components.

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PURPOSE: To evaluate the sulcus anatomy and possible correlations between sulcus diameter and white-to-white (WTW) diameter in pseudophakic eyes, data that may be important in the stability of add-on intraocular lenses (IOLs). SETTING: University Eye Hospital, Tuebingen, Germany. DESIGN: Case series. METHODS: In pseudophakic eyes, the axial length (AL) and horizontal WTW were measured by the IOLMaster device. Cross-sectional images were obtained with a 50 MHz ultrasound biomicroscope on the 4 meridians: vertical, horizontal (180 degrees), temporal oblique, and nasal oblique. Sulcus-to-sulcus (STS), angle-to-angle (ATA), and sclera-to-sclera (ScTSc) diameters were measured. The IOL optic diameter (6.0 mm) served as a control. To test reliability, optic measurements were repeated 5 times in a subset of eyes. RESULTS: The vertical ATA and STS diameters were statistically significantly larger than the horizontal diameter (P=.0328 and P=.0216, respectively). There was no statistically significant difference in ScTSc diameters. A weak correlation was found between WTW and horizontal ATA (r = 0.5766, P<.0001) and between WTW and horizontal STS (r = 0.5040, P=.0002). No correlation was found between WTW and horizontal ScTSc (r = 0.2217, P=.1217). CONCLUSIONS: The sulcus anatomy had a vertical oval shape with the vertical meridian being the largest, but it also had variation in the direction of the largest meridian. The WTW measurements showed a weak correlation with STS. In pseudophakic eyes, Soemmerring ring or a bulky haptic may affect the ciliary sulcus anatomy.

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Biometric relationships were recorded for 2431 male and female Panulirus echinatus sampled at Tamandare coastal reefs, Pernambuco, Brazil. The following body measurements were taken: carapace length and width, abdomen length and width, total length, third and fifth pereiopod length, cephalothorax-abdomen and total weight. Twelve relationships were studied to compare the biometric characteristics Of males and females. Eleven of them showed difference between the sexes. Comparing sexes with the same carapace length, males have a heavier cephalothorax and longer third and fifth pereiopods than females, whereas females are longer, wider, and have a heavier abdomen than males. For genders with the same total length, males are heavier and have a longer carapace than females, while females have a larger abdomen. For genders with the same abdomen length, males have a heavier abdomen than females. The relationships TWg/TL and A Wg/AL showed positive allometric growth for the males. All other relationships involving weight, presented negative allometric growth for both sexes.

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The human eye is sensitive to visible light. Increasing illumination on the eye causes the pupil of the eye to contract, while decreasing illumination causes the pupil to dilate. Visible light causes specular reflections inside the iris ring. On the other hand, the human retina is less sensitive to near infra-red (NIR) radiation in the wavelength range from 800 nm to 1400 nm, but iris detail can still be imaged with NIR illumination. In order to measure the dynamic movement of the human pupil and iris while keeping the light-induced reflexes from affecting the quality of the digitalized image, this paper describes a device based on the consensual reflex. This biological phenomenon contracts and dilates the two pupils synchronously when illuminating one of the eyes by visible light. In this paper, we propose to capture images of the pupil of one eye using NIR illumination while illuminating the other eye using a visible-light pulse. This new approach extracts iris features called "dynamic features (DFs)." This innovative methodology proposes the extraction of information about the way the human eye reacts to light, and to use such information for biometric recognition purposes. The results demonstrate that these features are discriminating features, and, even using the Euclidean distance measure, an average accuracy of recognition of 99.1% was obtained. The proposed methodology has the potential to be "fraud-proof," because these DFs can only be extracted from living irises.

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This study aimed at analyzing the relationship between slow- and fast-alpha asymmetry within frontal cortex and the planning, execution and voluntary control of saccadic eye movements (SEM), and quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 12 healthy participants performing a fixed (i.e., memory-driven) and a random SEM (i.e., stimulus-driven) condition. We find main effects for SEM condition in slow- and fast-alpha asymmetry at electrodes F3-F4, which are located over premotor cortex, specifically a negative asymmetry between conditions. When analyzing electrodes F7-F8, which are located over prefrontal cortex, we found a main effect for condition in slow-alpha asymmetry, particularly a positive asymmetry between conditions. In conclusion, the present approach supports the association of slow- and fast-alpha bands with the planning and preparation of SEM, and the specific role of these sub-bands for both, the attention network and the coordination and integration of sensory information with a (oculo)-motor response. (C) 2011 Elsevier B.V. All rights reserved.

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In the present study, mitochondrial (mt)DNA sequence data were used to examine the genetic structure of fire-eye antbirds (genus Pyriglena) along the Atlantic Forest and the predictions derived from the river hypothesis and from a Last Glacial Maximum Pleistocene refuge paleomodel were compared to explain the patterns of genetic variation observed in these populations. A total of 266 individuals from 45 populations were sampled over a latitudinal transect and a number of phylogeographical and population genetics analytical approaches were employed to address these questions. The pattern of mtDNA variation observed in fire-eye antbirds provides little support for the view that populations were isolated by the modern course of major Atlantic Forest rivers. Instead, the data provide stronger support for the predictions of the refuge model. These results add to the mounting evidence that climatic oscillations appear to have played a substantial role in shaping the phylogeographical structure and possibly the diversification of many taxa in this region. However, the results also illustrate the potential for more complex climatic history and historical changes in the geographical distribution of Atlantic Forest than envisioned by the refuge model. (c) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 900824.

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Purpose: To analyze the results of recall absent schoolchildren to eye health projects. Methods: Cross-sectional study. Visual screening was performed in schoolchildren attending 1st to 4th grades at public schools, from 7 to 10 years-old, to select and forward to complete ophthalmic evaluation. The projects were performed during weekends, at a public school, in the same municipality. Free transportation, food and eyeglasses were offered. A second opportunity of examination was offered to the students who were absent from the first call, with the same facilities. Results: 51,509 schoolchildren had their vision tested, 14,651 (28.4%) were referred for ophthalmic examination. Of these, 8,683 (59.3%) attended the first call, 2,228 (37.3%) attended the recall and 25.5% of parents did not take their children to ophthalmic examination. The need for eyeglasses for children who attended the examination was 23.8% and 32.0% in the first opportunity and recall, respectively. The recall increased the coverage in 15.2% (59.3% to 74.5%). Conclusion: An expressive number of parents (25.5%) did not bring their children to be examined, even at a second opportunity of exam. The facilities offered: access, free examination, transportation and glasses. Children who were absent in the first opportunity and appeared at recall had a greater need for eyeglasses. Recall increased the coverage in 15.2% (59.3% to 74.5%) and it is not recommended when financial resources are limited.

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The objective of this work was to study the morphology and biometry of the infraorbital foramen (FIO), variations in its shape, size and number as well as to obtain measurements of its location. 60 dry skulls were analyzed. The test of Qui-quadrant and the T Test were used in measurements with a 5% significance. On the right side, the FIO was measured at a distance of 6.49(+/- 1.68) mm from the lower, 39.65(+/- 3) mm from the upper, 17.7(+/- 2.97) mm from the medial and 20.46(+/- 2.9) mm from the lateral margin of the orbit; its pear-shaped opening distance was 13.67(+/- 2.17) mm. On the left side, the distance of the FIO to the lower margin of the orbit was 6.52(+/- 1.82) mm; to the upper margin was 39.9(+/- 2.62) mm and to the lateral and medial margin were 17.93(+/- 2.58) mm and 21.12(+/- 3) mm, respectively; its distance to the pear-shaped opening was 14.26(+/- 1.83) mm. It was found predominately in an oval shape, in 39 (65%) of the skulls, on both sides. Accessory foramens were present in 11 samples on the right and in 15 samples on the left side. The FIO was most frequently found on the side of, or laterally to the sagittal plane that passes through the middle of the supraorbital foramen/incisures, in 38 skulls (63.3%) on the right side and in 45 skulls (75%) on the left and middle to the zigomatic-maxillary suture, in 41 skulls (68.3%) on right and in 42 skulls (70%) on the left side, besides being most frequently found in a region between the first and second premolars, in 22 skulls (36.7%) on the right side and in 17 skulls (28.3%) on the left.

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We describe a girl with a phenotype characterized by frontonasal dysplasia, callosal agenesis, basal encephalocele, and eye anomalies who presents a 46,XX,r(21) karyotype. Array-comparative genomic hybridization using the Afflymetrix 100K DNA oligoarray set showed an interstitial deletion 21q22.3 of approximately 219?kb. Conventional karyotype of both parents was normal, and it was not possible to perform the molecular studies. In this report we raise the hypothesis that the deleted genes located at 21q22.3 could account to the phenotype. (C) 2012 Wiley Periodicals, Inc.

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Purpose: Fungi are a major cause of keratitis, although few medications are licensed for their treatment. The aim of this study is to observe the variation in commercialisation of antifungal eye drops, and to predict the seasonal distribution of fungal keratitis in Brazil. Methods: Data from a retrospective study of antifungal eye drops sales from the only pharmaceutical ophthalmologic laboratory, authorized to dispense them in Brazil (Opthalmos) were gathered. These data were correlated with geographic and seasonal distribution of fungal keratitis in Brazil between July 2002 and June 2008. Results: A total of 26,087 antifungal eye drop units were sold, with a mean of 2.3 per patient. There was significant variation in antifungal sales during the year (p < 0.01). A linear regression model displayed a significant association between reduced relative humidity and antifungal drug sales (R-2 = 0.17, p < 0.01). Conclusions: Antifungal eye drops sales suggest that there is a seasonal distribution of fungal keratitis. A possible interpretation is that the third quarter of the year (a period when the climate is drier), when agricultural activity is more intense in Brazil, suggests a correlation with a higher incidence of fungal keratitis. A similar model could be applied to other diseases, that are managed with unique, or few, and monitorable medications to predict epidemiological aspects.

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Introduction: The saccadic paradigm has been used to investigate specific cortical networks involving attention. The behavioral and electrophysiological investigations of the SEM contribute significantly to the understanding of attentive patterns presented of neurological and psychiatric disorders and sports performance. Objective: The current study aimed to investigate absolute alpha power changes in sensorimotor brain regions and the frontal eye fields during the execution of a saccadic task. Methods: Twelve healthy volunteers (mean age: 26.25; SD: +/- 4.13) performed a saccadic task while the electroencephalographic signal was simultaneously recorded for the cerebral cortex electrodes. The participants were instructed to follow the LEDs with their eyes, being submitted to two different task conditions: a fixed pattern versus a random pattern. Results: We found a moment main effect for the C3, C4, F3 and F4 electrodes and a condition main effect for the F3 electrode. We also found interaction between factor conditions and frontal electrodes. Conclusions: We conclude that absolute alpha power in the left frontal cortex discriminates the execution of the two stimulus presentation patterns during SEM. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

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Ocular enucleation produces significant morphological and physiological changes in central visual areas. However, our knowledge of the molecular events resulting from eye enucleation in visual brain areas remains elusive. We characterized here the transcription nuclear factor kappa-B (NF-kappa B) activation induced by ocular enucleation in the rat superior colliculus (SC). We also tested the effectiveness of the synthetic glucocorticoid dexamethasone in inhibiting its activation. Electrophoretic mobility shift assays to detect NF-kappa B indicated that this transcription factor is activated in the SC from 1 h to day 15 postlesion. The expression of p65 and p50 proteins in the nuclear extracts was also increased. Dexamethasone treatment was able to significantly inhibit NF-kappa B activation. These findings suggest that this transcriptional factor is importantly involved in the visual system short-term processes that ensue after retinal lesions in the adult brain. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

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A small supernumerary marker chromosome (sSMC) derived from chromosome 22 is a relatively common cytogenetic finding. This sSMC typically results in tetrasomy for a chromosomal region that spans the chromosome 22p arm and the proximal 2 Mb of 22q11.21. Using classical cytogenetics, fluorescence in situ hybridization, multiplex ligation-dependent probe amplification, and array techniques, 7 patients with sSMCs derived from chromosome 22 were studied: 4 non-related and 3 from the same family (mother, daughter, and son). The sSMCs in all patients were dicentric and bisatellited chromosomes with breakpoints in the chromosome 22 low-copy repeat A region, resulting in cat eye syndrome (CES) due to chromosome 22 partial tetrasomy 22pter -> q11.2 including the cat eye chromosome region. Although all subjects presented the same chromosomal abnormality, they showed a wide range of phenotypic differences, even in the 3 patients from the same family. There are no previous reports of CES occurring within 3 patients in the same family. Thus, the clinical and follow-up data presented here contribute to a better delineation of the phenotypes and outcomes of CES patients and will be useful for genetic counseling. Copyright (C) 2012 S. Karger AG, Basel

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Purpose: To report the clinical outcome of the treatment of dry eyes using 0.03% tacrolimus eye drops (olive oil + tacrolimus 0.03%) (Ophthalmos, Sao Paulo, Brazil). Methods: Sixteen eyes of 8 patients with Sjogren syndrome dry eyes (age, 51.13 +/- 9.45 years) were enrolled in this study (prospective noncontrolled interventional case series). Patients were instructed to use topical 0.03% tacrolimus eye drops twice a day (every 12 hours) in the lower conjunctival sac. Schirmer I test, break-up time, corneal fluorescein, and rose bengal staining score were performed in all patients 1 day before, and 14, 28, and 90 days after treatment with 0.03% tacrolimus eye drops. Results: The average fluorescein staining and rose bengal staining scores improved statistically significantly after 14 days of treatment and improved even more after 28 and 90 days. The average Schirmer I test did not improve statistically significantly after 28 days of treatment, although we did observe a significant improvement after 90 days of treatment with 0.03% tacrolimus eye drops. The average break-up time did not improve statistically after 14 days of treatment, although we observed a significant improvement after 28 and 90 days of treatment with 0.03% tacrolimus eye drops. Conclusions: Topical 0.03% tacrolimus eye drops successfully improved tear stability and ocular surface status in patients with dry eyes.

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OBJECTIVE: This study sought to compare the effects and outcomes of two ophthalmic viscosurgical devices, 1.6% hyaluronic acid/4.0% chondroitin sulfate and 2.0% hydroxypropylmethylcellulose, during phacoemulsification. METHODS: This prospective, randomized clinical trial comprised 78 eyes (39 patients) that received phacoemulsification performed by the same surgeon using a standardized technique. Patients were randomly assigned to receive either 1.6% hyaluronic acid/4.0% chondroitin sulfate or 2.0% hydroxypropylmethylcellulose on the first eye. The other eye was treated later and received the other viscoelastic agent. Preoperative and postoperative examinations (5, 24 and 48 hours; 7 and 14 days; 3 and 6 months) included measurements of the total volume of the ophthalmic viscosurgical device, ultrasound and washout times to completely remove the ophthalmic viscosurgical device, intraocular pressure, central corneal thickness and best-corrected visual acuity. The corneal endothelial cell count was measured at baseline and at six months postoperatively. ClinicalTrials.gov: NCT01387620. RESULTS: There were no statistically significant differences between groups in terms of cataract density or ultrasound time. However, it took longer to remove 2.0% hydroxypropylmethylcellulose than 1.6% hyaluronic acid/ 4.0% chondroitin sulfate, and the amount of viscoelastic material used was greater in the 2.0% hydroxypropylmethylcellulose group. In addition, the best-corrected visual acuity was significantly better in the hyaluronic acid/ chondroitin sulfate group, but this preferable outcome was only observed at 24 hours after the operation. There were no statistically significant differences between the two ophthalmic viscosurgical devices regarding the central corneal thickness or intraocular pressure measurements at any point in time. The corneal endothelial cell count was significantly higher in the hyaluronic acid/chondroitin sulfate group. CONCLUSION: The ophthalmic viscosurgical device consisting of 1.6% hyaluronic acid/4.0% chondroitin sulfate was more efficient during phacoemulsification and was easier to remove after IOL implantation than 2.0% hydroxypropylmethylcellulose. In addition, the corneal endothelial cell count was significantly higher following the use of hyaluronic acid/chondroitin sulfate than with hydroxypropylmethylcellulose, which promoted an improved level of corneal endothelium protection.