1. Articles from scielo.br

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    1. Evaluation of toxic retinopathy caused by antimalarial medications with spectral domain optical coherence tomography

      Evaluation of toxic retinopathy caused by antimalarial medications with spectral domain optical coherence tomography

      Purpose: To investigate the frequency of toxic retinopathy in patients with lupus erythematosus and rheumatoid arthritis with long-term use of chloroquine diphosphate or hydroxychloroquine through spectral domain optical coherence tomography and the outcomes of ophthalmological exams (visual acuity - Snellen’s table, color vision test - Ishihara’s table, fundoscopy, and retinography - red-free). Methods: A cross-sectional study was carried out involving the ophthalmologic evaluation of patients using regular chloroquine diphosphate or hydroxychloroquine for a period of 1 year or longer. The patients completed a questionnaire on their opinions and treatment regularity. The same patients underwent ophthalmologic examination and spectral domain optical coherence ...

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    2. Optical coherence tomography (OCT) angiography of central retinal artery occlusion in the patent cilioretinal artery: a case report

      Optical coherence tomography (OCT) angiography of central retinal artery occlusion in the patent cilioretinal artery: a case report

      Here we report the case of a 78-year-old male patient with a 2-day history of low visual acuity and fundus and who was diagnosed with central retinal artery occlusion. In addition, the patient had an allergy to fluorescein. A fundus examination of the left eye found a pink optic disc with blurred margins, diffuse pallor in the retina with arterial attenuation, and a normal band of the retinal area in the macular region. Optical coherence tomography revealed increased thickness of the inner retina. Optical coherence tomography angiography (OCT-A) revealed a decreased flow signal in the superficial layers, with reduced flow ...

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    3. Evaluation of a birth-related foveal hemorrhage in an infant using optical coherence tomography

      Evaluation of a birth-related foveal hemorrhage in an infant using optical coherence tomography

      During the routine ophthalmologic examination of a 38-day old female infant, indirect ophthalmoscopy revealed a dense hemorrhage on the fovea and a couple of superficial hemorrhages in the nasal retina of the left eye. No hemorrhage was observed in the right eye. A hand-held spectral domain optical coherence tomography (SD-OCT) was used at the time of diagnosis. The hemorrhage at the nasal retina resolved in the first week of follow-up, and the foveal hemorrhage resolved 12 weeks after birth. Spectral domain optical coherence tomography was repeated once the foveal hemorrhage had resorbed, and it showed that the foveal contour had ...

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    4. Normative values for optical coherence tomography parameters in healthy children and interexaminer agreement for choroidal thickness measurements

      Normative values for optical coherence tomography parameters in healthy children and interexaminer agreement for choroidal thickness measurements

      Purpose: To (a) determine the normative values for optical coherence tomography (OCT) parameters such as central macular thickness, retinal nerve fiber layer thickness, and choroidal thickness in healthy children; (b) investigate the relationships of these parameters with axial length, central corneal thickness, refractive errors, and intraocular pressure; and (c) determine interexaminer agreement for choroidal thickness measurements. Methods: In this cross-sectional study, 120 healthy children aged 8-15 years underwent detailed ophthalmological examination and OCT measurements. Choroidal thickness was measured at three separate locations by two independent examiners. Results: The mean global retinal nerve fiber layer thickness was 98.75 ± 9.45 ...

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    5. Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis

      Anterior segment optical coherence tomography findings in type I Boston keratoprosthesis

      Purpose: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). Methods: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure. Results: Preoperative diagnoses included chemical burn (55%), failed corneal transplant (36%), and Stevens-Johnson syndrome (9%). The mean postoperative follow-up duration ...

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    6. Evaluation of adaptation of ceramic inlays using optical coherence tomography and replica technique

      Evaluation of adaptation of ceramic inlays using optical coherence tomography and replica technique

      Optical coherence tomography (OCT) has generally been used as a nondestructive technique to evaluate integrities of composite restorations. We investigated marginal and internal adaptations of ceramic inlay restorations with OCT and compared them to results with the silicone replica technique. Round-shaped class I cavities were prepared on 16 human maxillary first premolar teeth. Ceramic inlays were fabricated. Silicone replicas from inlays were obtained and sectioned to measure marginal and internal adaptations with a stereomicroscope (Leica Dfc 295, Bensheim, Germany). Inlays were cemented on respective teeth. Marginal and internal adaptations were then measured with the OCT system (Thorlabs, New Jersey, USA ...

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      Mentions: Thorlabs Leica
    7. Repeatability and reproducibility of automatic segmentation of retinal layers in healthy subjects using Spectralis optical coherence tomography

      Repeatability and reproducibility of automatic segmentation of retinal layers in healthy subjects using Spectralis optical coherence tomography

      Purpose: To evaluate the repeatability and reproducibility of automatic segmentation in healthy subjects using a Spectralis optical coherence tomography (OCT) system. Methods: A total of 60 eyes from 60 patients were included in this prospective study. Spectral-domain optical coherence tomography images were generated using the Spectralis OCT system. An automated algorithm was used to segment the macular retina into nine layers and evaluate the thickness of each layer in the foveal, inner, and outer Early Treatment Diabetic Retinopathy Study (ETDRS) subfield rings. The eyes were imaged three times by an examiner to assess intraobserver repeatability and imaged once by a ...

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    8. Optical coherence tomography angiography artifactual choroidal neovascularization in optic disc pit maculopathy

      Optical coherence tomography angiography artifactual choroidal neovascularization in optic disc pit maculopathy

      This case report describes a 19-year-old Caucasian man presented with decreased visual acuity in the right eye for 3 months. Dilated funds exam revealed optic disk pit associated with serous macular detachment. Optical coherence tomography identified communication between the optic disk pit and the macular serous detachment, and optical coherence tomography angiography displayed a subfoveal area suggestive of subfoveal choroidal neovascularization. However, there was no evidence of leakage in the fluorescein angiogram and no evidence of choroidal neovascularization in optical coherence tomography in the area corresponding to the suspicious subfoveal choroidal neovascularization. The patient underwent 23-gauge pars plana vitrectomy in ...

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    9. Choroidal neovascularization silent on optical coherence tomography: report of two cases

      Choroidal neovascularization silent on optical coherence tomography: report of two cases

      Herein, we report two cases of vision loss after successful cataract surgery, associated with drusenoid retinal pigment epithelial detachment without features of choroidal neovascularization on optical coherence tomography along with angiographic examinations suggestive of choroidal neovascularization in which anatomical and functional improvements were achieved with intravitreal injections of anti-vascular endothelial growth factor.

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    10. En face and OCT angiography findings in macular retinoschisis

      En face and OCT angiography findings in macular retinoschisis

      The diagnosis of macular retinoschisis is often complex and demands complementary exams to be confirmed. This is the report of a case of a 27 years old man diagnosed with macular retinoschisis, in which En face OCT and OCT angiography were used to identify and demonstrate the typical patterns of the disease, as well as distinguish them from the findings of cystoid macular edema.

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    11. Structure-functional correlation using adaptive optics, OCT, and microperimetry in a case of occult macular dystrophy

      Structure-functional correlation using adaptive optics, OCT, and microperimetry in a case of occult macular dystrophy

      We report retinal functional and structural changes of a 40-year-old man diagnosed with occult macular dystrophy. Comprehensive ophthalmological evaluation was performed, followed by spectral-domain optical coherence tomography (SD-OC - Heidelberg) and image acquisition using an adaptive optics (AO) camera (RTX1, Imagine Eyes) for photoreceptor density analysis. Functional tests included full-field ERG (ERG) and multifocal electroretinography (mfERG) (Diagnosys, LLC) and microperimetry with scanning laser ophthalmoscope (SLO) fixation controlled (MAIA, CenterVUE). OCT revealed a line of discontinuity corresponding to cone outer-segment photoreceptors associated with a loss of cone density, highlighted by a dark blue spot on the AO co ne-density map on the ...

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    12. Comparison of optical coherence tomographic findings between Behcet disease patients with and without ocular involvement and healthy subjects

      Comparison of optical coherence tomographic findings between Behcet disease patients with and without ocular involvement and healthy subjects

      ABSTRACT Purpose: We aimed to compare the retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, and the choroid thickness between patients with Behcet disease and healthy subjects by using spectral domain optical coherence tomography (SD-OCT). Methods: Ninety eyes of 45 healthy subjects and 104 eyes of 52 patients with Behcet disease were included in this study. Rheumatoid factor and C-reactive protein levels were measured by blood testing in the patients. Results: The mean thickness of the retinal nerve fiber layer, ganglion cells layer, and inner plexiform layer were significantly lower in patients with Behcet's disease than in ...

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    13. Comparisons of choroidal nevus measurements obtained using 10- and 20-MHz ultrasound and spectral domain optical coherence tomography

      Comparisons of choroidal nevus measurements obtained using 10- and 20-MHz ultrasound and spectral domain optical coherence tomography

      Purpose: To compare measurements of lesions clinically diagnosed as choroidal nevi using spectral domain optical coherence tomography (SD-OCT) and 10- and 20-MHz ultrasound (US). Methods: This prospective study, which was conducted between May 2011 and December 2011, evaluated eyes diagnosed with choroidal nevus via photographic documentation using 10- or 20-MHz A- and B-mode US (experienced examiner using both the transpalpebral technique and direct contact) or SD-OCT in the enhanced depth imaging mode (performed by a different examiner blinded to the US results). Anteroposterior (AP) and transverse (T) US sections corresponded to sections adjusted perpendicularly on SD-OCT. Results: We evaluated 14 ...

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    14. Large colloid drusen analyzed with structural en face optical coherence tomography

      Large colloid drusen analyzed with structural en face optical coherence tomography

      Drusen are extracellular deposits between the basal lamina of the retinal pigment epithelium (RPE) and the inner collagenous layer of Bruch's membrane. Large colloid drusen (LCD) are located below the RPE and are characterized by multiple, large, dome-shaped RPE detachments, with marked attenuation of the ellipsoid zone overlaying the drusen. This report presents the structural en face optical coherence tomography (OCT) findings of LCD and relates them to findings from fluorescein and indocyanine green angiography. We describe the case of a 55-year-old woman who presented with the chief complaint of a 5-year history of progressively worsening vision. Her best-corrected ...

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    15. Optical coherence tomography in congenital Zika syndrome

      Optical coherence tomography in congenital Zika syndrome

      Dear Editor: I read with interest the article by Campos et al. ( 1 ) on optical coherence tomography (OCT) findings in congenital Zika virus infection or congenital Zika syndrome (CZS). Six months after the onset of a Zika virus outbreak, there was an unusual 20-fold increase in microcephaly cases in newborns in Brazil ( 2 ) . Ventura et al. ( 2 ) were the first to report ocular involvement in CZS in the form of loss of foveal reflex and macular pigmentary mottling in three infants. One infant also had a well-defined patch of retinal atrophy at the macula ( 2 ) . In another report ( 3 ) , Ventura ...

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    16. Approaches to segment stent area from Intravascular Optical Coherence Tomography

      Approaches to segment stent area from Intravascular Optical Coherence Tomography

      Introduction Cardiovascular diseases (CVD) have been the focus of research in recent years due to its high mortality rate. It is estimated that 17.5 million people died of CVD in 2012, from which 7.4 million were due to coronary heart disease (CHD). In order to monitor CHD patients and avoid waste of specialists' time, this study proposes the development of a method that segments the area contained by stent struts from Frequency Domain Intravascular Optical Coherence Tomography (the latest technology to view vessels internally) of coronary arteries. Methods The novelty of this study is to find areas comprised ...

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    17. Optical coherence tomography of macular atrophy associated with microcephaly and presumed intrauterine Zika virus infection

      Optical coherence tomography of macular atrophy associated with microcephaly and presumed intrauterine Zika virus infection

      This case report describes the retinal optical coherence tomography (OCT) findings in a microcephalic infant with macular atrophy presumably caused by intrauterine Zika virus infection. OCT demonstrated atrophy of the outer retinal layers and choriocapillaris, including the outer nuclear layer and ellipsoid zone, associated with retinal pigment epithelium hyper-reflectivity and increased OCT penetration into deeper layers of the choroid and sclera. A major concern associated with this infection is the apparent increased incidence of microcephaly in fetuses born to mothers infected with the Zika virus. It is becoming increasingly difficult to ignore the upsurge in congenital microcephaly observed in Brazil ...

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    18. Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography

      Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography

      Purpose: To assess the effect of hemodialysis on retinal and choroidal thicknesses using spectral-domain optical coherence tomography (SD-OCT). Methods: In this prospective interventional study, 25 hemodialysis patients (17 male, 8 female) were enrolled. All participants underwent high-speed, high-resolution SD-OCT (λ=840 mm; 26.000 A-scans/s; 5 µm resolution) before and after hemodialysis. Choroidal thickness was measured perpendicularly from the outer edge of the retinal pigment epithelium to the choroid-sclera boundary at the fovea and at five additional points: 500 µm and 1000 µm nasal to the fovea and 500 µm, 1000 µm, and 1500 µm temporal to the fovea. Two ...

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    19. Enhanced depth imaging optical coherence tomography of choroidal osteoma with secondary neovascular membranes: report of two cases

      Enhanced depth imaging optical coherence tomography of choroidal osteoma with secondary neovascular membranes: report of two cases

      We report enhanced depth imaging optical coherence tomography (EDI-OCT) features based on clinical and imaging data from two newly diagnosed cases of choroidal osteoma presenting with recent visual loss secondary to choroidal neovascular membranes. The features described in the two cases, compression of the choriocapillaris and disorganization of the medium and large vessel layers, are consistent with those of previous reports. We noticed a sponge-like pattern previously reported, but it was subtle. Both lesions had multiple intralesional layers and a typical intrinsic transparency with visibility of the sclerochoroidal junction.

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    20. Spontaneous coronary artery dissection and healing documented by optical coherence tomography

      Spontaneous coronary artery dissection and healing documented by optical coherence tomography

      An otherwise healthy 57-year-old female patient with no risk factors for coronary artery disease presented to the emergency room with acute chest pain. The patient had been taking appetite suppressant (dimethylamylamine, Oxyelite Pro, (USP Labs) for the last 7 days. 1 , 2 Electrocardiography showed no abnormalities although both serum creatinine kinase-MB (3.59ng/mL) and troponin I (8,310pg/mL) were elevated. Coronary angiography revealed extensive and abrupt lumen narrowing in the obtuse marginal with a subtle intraluminal defect within the distal part of the vessel ( Figure 1 ). Optical coherence tomography (OCT), which is a novel near-infrared light based intravascular ...

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    21. A robust fully automatic lumen segmentation method for in vivo intracoronary optical coherence tomography

      A robust fully automatic lumen segmentation method for in vivo intracoronary optical coherence tomography

      Introduction: Intravascular optical coherence tomography (IVOCT) is an in-vivo imaging modality based on the introduction of a catheter in a blood vessel for viewing its inner wall using electromagnetic radiation. One of the most developed automatic applications for this modality is the lumen area segmentation, however on the evaluation of these methods, the slices inside bifurcation regions, or with the presence of complex atherosclerotic plaques and dissections are usually discarded. This paper describes a fully-automatic method for computing the lumen area in IVOCT images where the set of slices includes complex atherosclerotic plaques and dissections. Methods The proposed lumen segmentation ...

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    22. Effectiveness of fluoride sealant in the prevention of carious lesions around orthodontic brackets: an OCT evaluation

      Effectiveness of fluoride sealant in the prevention of carious lesions around orthodontic brackets: an OCT evaluation

      Objective: This article aimed to evaluate in vitro the efficiency of Pro Seal fluoride sealant application in the prevention of white spot lesions around orthodontic brackets. Material and Methods: Brackets were bonded to the buccal surface of bovine incisors, and five groups were formed (n = 15) according to the exposure of teeth to oral hygiene substances and the application of enamel sealant: G1 (control), only brushing was performed with 1.450 ppm fluoride; G2 (control) brushing associated with the use of mouthwash with 225 ppm fluoride; G3, only Pro Seal sealant application was performed with 1.000 ppm fluoride; G4 ...

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    23. Quantitative analysis of iris parameters in keratoconus patients using optical coherence tomography

      Quantitative analysis of iris parameters in keratoconus patients using optical coherence tomography

      Purpose: To investigate the relationship between quantitative iris parameters and the presence of keratoconus. Methods: Cross-sectional observational study that included 15 affected eyes of 15 patients with keratoconus and 26 eyes of 26 normal age- and sex-matched controls. Iris parameters (area, thickness, and pupil diameter) of affected and unaffected eyes were measured under standardized light and dark conditions using anterior segment optical coherence tomography (AS-OCT). To identify optimal iris thickness cutoff points to maximize the sensitivity and specificity when discriminating keratoconus eyes from normal eyes, the analysis included the use of receiver operating characteristic (ROC) curves. Results: Iris thickness and ...

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    24. Photonic Imaging with Optical Coherence Tomography for Quality Monitoring in the Poultry Industry: a Preliminary Study

      Photonic Imaging with Optical Coherence Tomography for Quality Monitoring in the Poultry Industry: a Preliminary Study

      A photonic imaging method that gives the possibility to measure egg quality was applied. Since the method is non-contact and non-destructive we believe that this photonic imaging method may be successfully integrated in the automated inspection systems in the poultry industry. The method involves scanning an invisible infrared light beam over the eggshell, allowing to detect possible cracks and reveal information about the structure of the eggshell. The high resolution, high quality measurements obtained through optical coherence tomography (OCT) make it feasible to be utilized as part of an automated inspection system. In this paper we present an OCT scan ...

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    1-24 of 53 1 2 3 »
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