LUCAS RAMOS DE PRETTO

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  • Artigo IPEN-doc 29026
    Long-term functioning status of COVID-19 survivors
    2022 - BATTISTELLA, LINAMARA R.; IMAMURA, MARTA; DE PRETTO, LUCAS R.; VAN CAUWENBERGH, SIMON K.H.A.A.; RAMOS, VINICIUS D.; UCHIYAMA, SABRINA S.T.; MATHEUS, DENISE; KUHN, FLAVIA; OLIVEIRA, ANA A.A. de; NAVES, GABRIELLA S.; MIRISOLA, ALINE R.; RIBEIRO, FERNANDO de Q.; SUGAWARA, ANDRE T.; CANTARINO, MAURICIO; CAVALCA, RAFAEL A.S.A.; PAGANO, VANESSA; MARQUES, MELINA V.; SILVA, ELIZABETH M. da; GOMES, ALESSANDRA P.; FREGNI, FELIPE
    Objectives The study investigated the long-term functional status of hospitalised COVID-19 survivors to explore and document their functional situation. Design This prospective observational study assessed 801 COVID-19 survivors at 3–11 months after hospital discharge. It analyses participants' sociodemographic background, COVID-19 clinical manifestations, and clinical and functional evaluations. Setting Tertiary-level university hospital in São Paulo, Brazil. Participants Study participants are COVID-19 survivors admitted to hospital care for at least 24 hours to treat acute SARS-CoV-2 infection. Outcome measures Epworth Sleepiness Scale, EuroQoL-5 Dimensions-5 Levels, Functional Assessment of Chronic Illness Therapy–Fatigue, Functional Independence Measure, Functional Oral Intake Scale, Handgrip Strength, Insomnia Severity Index, Medical Research Council (MRC) Dyspnea Scale, MRC sum score, Modified Borg Dyspnea Scale, pain Visual Analogue Scale, Post-COVID-19 Functional Status, Timed Up and Go, WHO Disability Assessment Schedule 2.0, 1-Minute Sit to Stand Test. Results Many participants required invasive mechanical ventilation (41.57%, 333 of 801). Mean age was 55.35±14.58 years. With a mean of 6.56 (SD: 1.58; 95% CI: 6.45 to 6.67) months after hospital discharge, 70.86% (567 of 800) reported limited daily activities, which were severe in 5.62% (45 of 800). They also reported pain and discomfort (64.50%, 516 of 800), breathlessness (64.66%, 514 of 795), and anxiety and depression (57.27%, 457 of 798). Daytime sleepiness and insomnia evaluations showed subthreshold results. Most (92.85%, 727 of 783) participants reported unrestricted oral intake. Data indicated no generalised fatigue (mean score: 39.18, SD: 9.77; 95% CI: 38.50 to 39.86). Assessments showed poor handgrip strength (52.20%, 379 of 726) and abnormal Timed Up and Go results (mean 13.07 s, SD: 6.49). The invasive mechanical ventilation group seemed to have a better handgrip strength however. We found no clear trends of change in their functional status during months passed since hospital discharge. Conclusions Muscle weakness, pain, anxiety, depression, breathlessness, reduced mobility, insomnia and daytime sleepiness were the most prevalent long-term conditions identified among previously hospitalised COVID-19 survivors.
  • Artigo IPEN-doc 28418
    Rehabilitation of patients after COVID-19 recovery
    2021 - IMAMURA, MARTA; MIRISOLA, ALINE R.; RIBEIRO, FERNANDO de Q.; DE PRETTO, LUCAS R.; ALFIERI, FABIO M.; DELGADO, VINICIUS R.; BATTISTELLA, LINAMARA R.
    OBJECTIVES: As patients recovering from the novel coronavirus disease 2019 (COVID-19) present with physical, respiratory, cognitive, nutritional, and swallowing-related impairments and mental health complications, their rehabilitation needs are complex. This study aimed to describe the demographic, clinical, and functional status after the discharge of COVID-19 survivors who underwent intensive multidisciplinary inpatient rehabilitation at the Physical and Rehabilitation Medicine Institute of the University of Sao Paulo Medical School General Hospital and Lucy Montoro Rehabilitation Institute. We determined the most important factors related to the length of inpatient rehabilitation treatment and present the functional outcomes. METHODS: This was a retrospective study based on electronic medical records. In addition to the severity of COVID-19 and length of hospital stay for the management of COVID-19 and comorbidities, we collected sociodemographic data including age, sex, height, and weight. Functional assessments were performed using the Functional Independence Measure (FIM); Short Physical Performance Battery; Montreal Cognitive Assessment; Depression, Anxiety and Stress Scale; Revised Impact of Events Scale; bioelectrical impedance; Functional Oral Intake Scale; oropharyngeal dysphagia classification; and nutritional assessment. RESULTS: There was a significant improvement in FIM before and after inpatient rehabilitation treatment (p<0.0001). Muscle strength and walking capacity were significantly improved (p<0.01). The most important factors related to the length of inpatient rehabilitation treatment were improvement in FIM scores (Spearman’s r=0.71) and gain in lean mass (Spearman’s r=0.79). CONCLUSIONS: Rehabilitation of patients after COVID-19 recovery improves their functional status and should be considered in the post-acute phase for selected patients with COVID-19.
  • Resumo IPEN-doc 27450
    Assessment of osteoporosis through laser speckle imaging
    2020 - AMARAL, M.M.; DEL-VALLE, M.; RAELE, M.P.; PRETTO, L.R. de; ANA, P.A.
  • Artigo IPEN-doc 27433
    Nondestructive evaluation of fused filament fabrication 3D printed structures using optical coherence tomography
    2020 - DE PRETTO, LUCAS R.; AMARAL, MARCELO M.; FREITAS, ANDERSON Z. de; RAELE, MARCUS P.
    Purpose – The quality of components under fused filament fabrication (FFF) is related to the correct filament spacing and bonding of successively deposited layers and is evaluated mainly by scanning electron microscopy (SEM). However, it is a destructive technique and real-time evaluation is not possible. Optical coherence tomography (OCT), on the other hand, is an optical method that acquires cross-sectional images non-invasively and in real-time. Therefore, this paper aims to propose and validate the use of OCT as a non-destructive quality evaluation tool for FFF using Polylactic Acid (PLA) filaments. Design/methodology/approach – PLA three-dimensional (3D) printed samples were made in a variety of nozzle temperatures and mesh spacing. These samples were fractured in liquid nitrogen and inspected using SEM (as a gold standard) to evaluate dimensions and morphology, then the samples were evaluated by OCT in the same area, allowing the results confrontation. Findings – Our results indicate a good correlation between OCT and SEM for the dimensional assessment of layers. When the filament was extruded in lower temperatures, the OCT images presented sharply defined interfaces between layers, in contrary to higher nozzle temperatures, denoting better fusion between them. However, higher extruding temperatures are incurred in greater deviations from nominal dimensions of the mesh. Finally, we demonstrate the advantage of a full 3D tomographic reconstruction to inspect within a FFF sample, which enabled the inspection of “hidden” information, not visible on a single cross-sectional cut. Originality/value – This paper proposes OCT as a novel and nondestructive evaluation tool for FFF.
  • Tese IPEN-doc 27274
    Desenvolvimento de técnicas diagnósticas quantitativas baseadas em decorrelação de speckle presente nos sinais de Tomografia de Coerência Óptica
    2019 - PRETTO, LUCAS R. de
    Segundo dados da Organização Mundial da Saúde (OMS), doenças crônicas não transmissíveis (DCNT), são uma das principais causas de morte no mundo, principalmente diabetes mellitus (DM). De particular importância para a DM, a manutenção de elevados níveis glicêmicos contribui de forma direta para o prejuízo das funções vasculares. Ainda, a DM impacta diretamente na qualidade de vida através de outros fatores associados à doença. Destaca-se a Retinopatia Diabética (RD), uma das principais causas de cegueira no mundo. A Tomografia por Coerência Óptica (OCT, do inglês, Optical Coherence Tomography) é uma modalidade de diagnóstico por imagem baseada em interferometria óptica que não utiliza radiação ionizante. Análise das flutuações de intensidade do sinal de OCT, devido ao padrão de ruído denominado speckle, possibilita análises angiográficas e de fluxo. Este estudo apresenta, então, o uso de OCT como ferramenta diagnóstica tanto para medir níveis glicêmicos no sangue de forma sem-contato, como para analisar in vivo a microvasculatura retinal. Desta maneira, novas técnicas diagnósticas para controle do nível glicêmico e para acompanhamento e estudo da retinopatia diabética são propostas. Os resultados de diferenciação da concentração de glicose no sangue obtidos, com métodos de análise espacial e temporal, são animadores e mostram boa sensibilidade do OCT para aplicações ex vivo, indicando uma potencial técnica de monitoramento glicêmico não-invasiva. Adicionalmente, as novas formas de análise microvascular da retina possibilitam um diagnóstico precoce da severidade da RD, o que possibilita melhor indicação do tratamento adequado a cada caso. Ainda, esta análise revela informações novas sobre a angiogênese da RD. É necessário, entretanto, um conhecimento adequado sobre as imagens adquiridas e métricas utilizadas, e um relatório sobre estes fatores foi desenvolvido. Com isto, esta tese demonstra a importância do desenvolvimento de técnicas de OCT para aplicações clínicas e para saúde dos pacientes com DM.
  • Artigo IPEN-doc 27141
    Osteoporosis evaluation through full developed speckle imaging
    2020 - AMARAL, MARCELLO M.; DEL-VALLE, MATHEUS; RAELE, MARCUS P.; DE PRETTO, LUCAS R.; ANA, PATRICIA A.
    Osteoporosis is a disease characterized by bone mineral density reduction, weakening the bone structure. Its diagnosis is performed using ionizing radiation, increasing health risk. Optical techniques are safer, due to non-ionizing radiation use, but limited to the analyses of bone tissue. This limitation may be circumvented in the oral cavity. In this work we explored the use of laser speckle imaging (LSI) to differentiate the sound and osteoporotic maxilla andmandible bones in an in vitro model. Osteoporosis lesions were simulated with acid attack. The samples were evaluated by optical profilometry and LSI, using a custom software. Two image parameters were evaluated, speckle contrast ration and patches ratio. With the speckle contrast ratio, it was possible to differentiate sound from osteoporotic tissue. From speckle patches ratio it was observed a negative correlation with the roughness parameter. LSI is a promissory technique for assessment of osteoporosis lesions on alveolar bone.
  • Artigo IPEN-doc 26892
    Quantification of retinal capillary nonperfusion in diabetics using wide-field optical coherence tomography angiography
    2020 - ALIBHAI, A.Y.; PRETTO, LUCAS R. de; MOULT, ERIC M.; OR, CHRIS; ARYA, MALVIKA; MCGOWAN, MITCHELL; CARRASCO-ZEVALLOS, OSCAR; LEE, BYUNGKUN; CHEN, SIYU; BAUMAL, CAROLINE R.; WITKIN, ANDRE J.; REICHEL, ELIAS; FREITAS, ANDERSON Z. de; DUKER, JAY S.; FUJIMOTO, JAMES G.; WAHEED, NADIA K.
    Purpose: To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR). Methods: Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm · 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion. Results: The mean percentage of nonperfused area was 0.1% (95% confidence interval: 0.0–0.4) in the eyes without DR; 2.1% (95% confidence interval: 1.2–3.7) in the nonproliferative DR eyes (mild, moderate, and severe), and 8.5% (95% confidence interval: 5.0–14.3) in the proliferative DR eyes. The percentage of nonperfused area increased in a statistically significant manner from eyes without DR, to eyes with nonproliferative DR, to eyes with proliferative DR. Conclusion: Capillary nonperfusion area in the posterior retina increases with increasing DR severity as measured by swept-source OCTA. Quantitative analysis of retinal nonperfusion on wide-field OCTA may be useful for early detection and monitoring of disease in patients with diabetes and DR.
  • Artigo IPEN-doc 26682
    Retinal nonperfusion relationship to arteries or veins observed on widefield optical coherence tomography angiography in diabetic retinopathy
    2019 - ISHIBAZAWA, AKIHIRO; PRETTO, LUCAS R. de; ALIBHAI, A. YASIN; MOULT, ERIC M.; ARYA, MALVIKA; SOROUR, OSAMA; MEHTA, NIHAAL; BAUMAL, CAROLINE R.; WITKIN, ANDRE J.; YOSHIDA, AKITOSHI; DUKER, JAY S.; FUJIMOTO, JAMES G.; WAHEED, NADIA K.
    PURPOSE. To evaluate whether retinal capillary nonperfusion is found predominantly adjacent to arteries or veins in eyes with diabetic retinopathy (DR). METHODS. Sixty-three eyes from 44 patients with proliferative DR (PDR) or non-PDR (NPDR) were included. Images (12 3 12-mm) foveal-centered optical coherence tomography (OCT) angiography (OCTA) images were taken using the Zeiss Plex Elite 9000. In 37 eyes, widefield montages with five fixation points were also obtained. A semiautomatic algorithm that detects nonperfusion in full-retina OCT slabs was developed, and the percentages of capillary nonperfusion within the total image area were calculated. Retinal arteries and veins were manually traced. Based on the shortest distance, nonperfusion pixels were labeled as either arterial-side or venous-side. Arterial-adjacent and venous-adjacent nonperfusion and the A/V ratio (arterial-adjacent nonperfusion divided by venous-adjacent nonperfusion) were quantified. RESULTS. Twenty-two eyes with moderate NPDR, 16 eyes with severe NPDR, and 25 eyes with PDR were scanned. Total nonperfusion area in PDR (median: 8.93%) was greater than in moderate NPDR (3.49%, P < 0.01). Arterial-adjacent nonperfusion was greater than venousadjacent nonperfusion for all stages of DR (P < 0.001). The median A/V ratios were 1.93 in moderate NPDR, 1.84 in severe NPDR, and 1.78 in PDR. The A/V ratio was negatively correlated with the total nonperfusion area (r ¼ 0.600, P < 0.0001). The results from the widefield montages showed similar patterns. CONCLUSIONS. OCTA images with arteries and veins traced allowed us to estimate the nonperfusion distribution. In DR, smaller nonperfusion tends to be arterial-adjacent, while larger nonperfusion tends toward veins.
  • Artigo IPEN-doc 26419
    Controlling for artifacts in widefield optical coherence tomography angiography measurements of non-perfusion area
    2019 - PRETTO, LUCAS R. de; MOULT, ERIC M.; ALIBHAI, A.Y.; CARRASCO-ZEVALLOS, OSCAR M.; CHEN, SIYU; LEE, BYUNGKUN; WITKIN, ANDRE J.; BAUMAL, CAROLINE R.; REICHEL, ELIAS; FREITAS, ANDERSON Z. de; DUKER, JAY S.; WAHEED, NADIA K.; FUJIMOTO, JAMES G.
    The recent clinical adoption of optical coherence tomography (OCT) angiography (OCTA) has enabled non-invasive, volumetric visualization of ocular vasculature at micron-scale resolutions. Initially limited to 3 mm × 3 mm and 6 mm × 6 mm fields-of-view (FOV), commercial OCTA systems now offer 12 mm × 12 mm, or larger, imaging fields. While larger FOVs promise a more complete visualization of retinal disease, they also introduce new challenges to the accurate and reliable interpretation of OCTA data. In particular, because of vignetting, wide-field imaging increases occurrence of low-OCT-signal artifacts, which leads to thresholding and/or segmentation artifacts, complicating OCTA analysis. This study presents theoretical and case-based descriptions of the causes and effects of low-OCTsignal artifacts. Through these descriptions, we demonstrate that OCTA data interpretation can be ambiguous if performed without consulting corresponding OCT data. Furthermore, using wide-field non-perfusion analysis in diabetic retinopathy as a model widefield OCTA usage-case, we show how qualitative and quantitative analysis can be confounded by low-OCT-signal artifacts. Based on these results, we suggest methods and best-practices for preventing and managing low-OCT-signal artifacts, thereby reducing errors in OCTA quantitative analysis of non-perfusion and improving reproducibility. These methods promise to be especially important for longitudinal studies detecting progression and response to therapy.
  • Artigo IPEN-doc 25775
    Focus tracking system for femtosecond laser machining using low coherence interferometry
    2019 - RAELE, MARCUS P.; DE PRETTO, LUCAS R.; ROSSI, WAGNER de; VIEIRA JUNIOR, NILSON D.; SAMAD, RICARDO E.
    We designed a real time, single-laser focus tracking system using low coherence properties of the machining femtosecond laser itself in order to monitor and correct the sample position relative to the focal plane. Using a Michelson Interferometer, the system collects data arising from part of the beam backscattered at the ablation spot. The data is analyzed by a custom software for position correction (employing an XYZ automated translation stage). With the focus tracking enabled we were able to etch channels with a stable cross-section profile on a bovine tooth with relief amplitude tens of times greater than the Rayleigh length of the system, keeping the sample inside the confocal parameter during most of the processing time. Moreover, the system is also capable of monitoring crater depth evolution during the ablation process, allowing for material removal assessment.