Primary Motor Area Activity in Phantom Limb Imagery of Traumatic Unilateral Lower Limb Amputees With Phantom Limb Pain.

Introduction: Estimates of the worldwide increase in amputees raises the awareness to solve long-standing problems. Understanding the functional brain modifications after a lower limb amputation (LLA) is one of the first steps towards proposing new rehabilitation approaches. Functional modifications in the central nervous system due the amputation could be involved in prosthesis use failures and Phantom Limb Pain (PLP), increasing costs and overwhelming the health services. Objective: This study analyses orphan primary motor area (M1-Orphan) hemodynamic and metabolic behaviour, which previously controlled the limb that was amputated, in comparison with the M1-Preserved, responsible for the intact limb (IL) during phantom limb imagery moving during Mirror Therapy (MT), compared to Isolated Intact Limb Movement Task (I-ILMT). Methodology: A case-control study with unilateral traumatic LLA with moderate PLP who measured [oxy-Hb] and [deoxy-Hb] in the M1 area by Functional Near InfraredSpectroscopy (fNIRS) during the real (I-ILMT) and MT task. Results: Sixty-five patients, with 67.69% of men, young (40.32 ± 12.91), 65.63% amputated due motorcycle accidents, 4.71 ± 7.38 years ago, predominantly above the knee (57.14%). The M1 activation in the orphan cortex did not differ from the activation in the intact cortex during MT (P > .05). Conclusion: The perception of the Phantom limb moving or intact limb moving is metabolically equivalent in M1, even in the absence of a limb. In other words, the amputation does not alter the brain metabolism in control of phantom movement.

Relationship between nonperfusion area from widefield optical coherence tomography angiography and macular vascular parameters in diabetic retinopathy.

PURPOSE: To evaluate the relationship between the nonperfusion area (NPA) from widefield optical coherence tomography angiography (OCTA) and macular vascular parameters in diabetic retinopathy (DR). METHODS: In total, 51 eyes from 51 patients with proliferative DR (PDR) or moderate/severe non-PDR were included. Widefield OCTA using the Zeiss Plex Elite 9000 was performed. A semi-automatic algorithm calculated the percentages of the NPA within the total image. Macular OCTA (3 × 3 mm and 6 × 6 mm area) was scanned using the RTVue-XR Avanti. Vessel density (VD) was automatically separated into the superficial (SCP) and deep capillary plexus (DCP), and foveal avascular zone (FAZ) measurements were computed according to the parafoveal (1-3 mm) and perifoveal (3-6 mm) regions. RESULTS: A negative correlation was found between the average VD of the SCP and DCP obtained 3 × 3 mm and 6 × 6 mm area and the NPA. Multiple regression analysis revealed that the temporal-perifoveal region most negatively correlated with the NPA (r = - 0.55, p < 0.0001). No correlation was found between FAZ measurements and DR severity (area, p = 0.07; perimeter, p = 0.13). CONCLUSION: Diabetic macular nonperfusion was significantly associated with the NPA from widefield OCTA. In particular, the temporal-perifoveal DCP disorder may be a sensitive indicator of wide NPA.

Digital Platform for Continuous Monitoring of Patients Using a Smartwatch: Longitudinal Prospective Cohort Study.

BACKGROUND: Since the COVID-19 pandemic, there has been a boost in the digital transformation of the human society, where wearable devices such as a smartwatch can already measure vital signs in a continuous and naturalistic way; however, the security and privacy of personal data is a challenge to expanding the use of these data by health professionals in clinical follow-up for decision-making. Similar to the European General Data Protection Regulation, in Brazil, the Lei Geral de Proteção de Dados established rules and guidelines for the processing of personal data, including those used for patient care, such as those captured by smartwatches. Thus, in any telemonitoring scenario, there is a need to comply with rules and regulations, making this issue a challenge to overcome. OBJECTIVE: This study aimed to build a digital solution model for capturing data from wearable devices and making them available in a safe and agile manner for clinical and research use, following current laws. METHODS: A functional model was built following the Brazilian Lei Geral de Proteção de Dados (2018), where data captured by smartwatches can be transmitted anonymously over the Internet of Things and be identified later within the hospital. A total of 80 volunteers were selected for a 24-week follow-up clinical trial divided into 2 groups, one group with a previous diagnosis of COVID-19 and a control group without a previous diagnosis of COVID-19, to measure the synchronization rate of the platform with the devices and the accuracy and precision of the smartwatch in out-of-hospital conditions to simulate remote monitoring at home. RESULTS: In a 35-week clinical trial, >11.2 million records were collected with no system downtime; 66% of continuous beats per minute were synchronized within 24 hours (79% within 2 days and 91% within a week). In the limit of agreement analysis, the mean differences in oxygen saturation, diastolic blood pressure, systolic blood pressure, and heart rate were -1.280% (SD 5.679%), -1.399 (SD 19.112) mm Hg, -1.536 (SD 24.244) mm Hg, and 0.566 (SD 3.114) beats per minute, respectively. Furthermore, there was no difference in the 2 study groups in terms of data analysis (neither using the smartwatch nor the gold-standard devices), but it is worth mentioning that all volunteers in the COVID-19 group were already cured of the infection and were highly functional in their daily work life. CONCLUSIONS: On the basis of the results obtained, considering the validation conditions of accuracy and precision and simulating an extrahospital use environment, the functional model built in this study is capable of capturing data from the smartwatch and anonymously providing it to health care services, where they can be treated according to the legislation and be used to support clinical decisions during remote monitoring.

Noninvasive Red Laser Intervention before Radiotherapy of Triple-negative Breast Cancer in a Murine Model.

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.

Noninvasive Red Laser Intervention before Radiotherapy of Triple-negative Breast Cancer in a Murine Model.

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.

Digital Platform to Continuously Monitor Patients Using a Smartwatch: Preliminary Report.

BACKGROUND: Monitoring vital signs such as oximetry, blood pressure, and heart rate is important to follow the evolution of patients. Smartwatches are a revolution in medicine allowing the collection of such data in a continuous and organic way. However, it is still a challenge to make this information available to health care professionals to make decisions during clinical follow-up. OBJECTIVE: This study aims to build a digital solution that displays vital sign data from smartwatches, collected remotely, continuously, reliably, and from multiple users, with trigger warnings when abnormal results are identified. METHODS: This is a single-center prospective study following the guidelines "Evaluating digital health products" from the UK Health Security Agency. A digital platform with 3 different applications was created to capture and display data from the mobile phones of volunteers with smartwatches. We selected 80 volunteers who were followed for 24 weeks each, and the synchronization interval between the smartwatch and digital solution was recorded for each vital sign collected. RESULTS: In 14 weeks of project progress, we managed to recruit 80 volunteers, with 68 already registered in the digital solution. More than 2.8 million records have already been collected, without system downtime. Less than 5% of continuous heart rate measurements (bpm) were synchronized within 2 hours. However, approximately 70% were synchronized in less than 24 hours, and 90% were synchronized in less than 119 hours. CONCLUSIONS: The digital solution is working properly in its role of displaying data collected from smartwatches. Vital sign values are being monitored by the research team as part of the monitoring of volunteers. Although the digital solution proved unsuitable for monitoring urgent events, it is more than suitable for use in outpatient clinical use. This digital solution, which is based on cloud technology, can be applied in the future for telemonitoring in regions lacking health care professionals. Accuracy and reliability studies still need to be performed at the end of the 24-week follow-up.

Long-term functioning status of COVID-19 survivors: a prospective observational evaluation of a cohort of patients surviving hospitalisation.

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.

Long COVID outpatient rehabilitation: a call for action / Reabilitação ambulatorial da COVID longa: uma chamada à ação

COVID-19 has motor, cognitive, psychological and nutritional consequences that require rehabilitation. Objetive: To describe the outpatient rehabilitation program developed at the Instituto de Medicina Física e Reabilitação do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Method: We collected sociodemographic and clinical data of 12 adults with laboratory-confirmed COVID-19, severe and critical, who needed hospitalization in the acute phase. Functional assessments included Functional Independence Scale (FIM), EQ-5D-5L, World Health Organization Disability Assessment Schedule (WHODAS 2.0), Post-COVID-19 Functional Status scale (PCFS), Medical Research Council (MRC) dyspnea scale, visual analog scale (VAS) for pain, Douleur Neuropathique 4 (DN-4), Epworth sleepiness scale, Insomnia Severity Index, Montreal Ontario Cognitive Assessment (MoCA), Depression, anxiety and stress scale (DASS-21), nutritional assessment, Timed Up and Go test, 10-meter walking test (10 MWT), handgrip strength, MRC sum score, musculoskeletal ultrasound of the thigh.The outpatient rehabilitation program included electrical and musculoskeletal inductive magnetic stimulation, extracorporeal shockwave treatment, isokinetic exercises, emotional approach, cognitive stimulation, occupational performance stimulation, nutritional guidance, and educational program by COMVC mobile application. Individualized program was delivered twice a week until pre-stablished discharge criteria was achieved. Results: VAS and TUG presented statistically significant improvements (p <0.001). PCFS, FIM, handgrip strength, 10 MWT and DASS-21 anxiety presented slopes in the direction of improvement. Conclusion: The optimized, intensive, interdisciplinary and short-term outpatient rehabilitation program improves pain, mobility and anxiety in long COVID patients.

A COVID-19 tem consequências sensório motoras, cognitivas, psíquicas e nutricionais que necessitam de reabilitação. Objetivo: Descrever o programa de reabilitação ambulatorial desenvolvido no Instituto de Medicina Física e Reabilitação do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, otimizado, intensivo e de curta duração. Método: Obtivemos informações sociodemográficas e clínicas de 12 adultos com diagnóstico laboratorial de COVID-19, grave e crítica, que necessitaram de hospitalização na fase aguda. Avaliações funcionais: Escala de Medida de Independência Funcional (MIF), EQ- 5D-5L, World Health Organization Disability Assessment Schedule (WHODAS 2.0), Post- COVID-19 Functional Status scale, Medical Research Council (MRC) dyspnea scale, escala visual analógica (EVA) para dor, DN-4 (Douleur Neuropathique 4), escala de sonolência de Epworth, Índice de Gravidade da Insônia, Montreal Ontario Cognitive Assessment (MoCA), escala de Depressão, ansiedade e estresse (DASS-21), avaliação nutricional, Timed Up and Go, teste de caminhada de 10 metros, teste de preensão palmar, MRC sum score, ultrassonografia musculoesquelética da coxa antes, durante e após programa de reabilitação ambulatorial. Este incluiu estimulação magnética indutiva e elétrica musculoesquelética, tratamento por ondas de choque extracorpóreas, exercícios isocinéticos, abordagem emocional, estimulação cognitiva, estimulação do desempenho ocupacional, orientação nutricional e programa educacional por aplicativo COMVC. O tratamento foi realizado duas vezes por semana até atingir os critérios de alta pré-estabelecidos. Resultados: VAS e TUG proporcionaram melhora estatisticamente significante (p <0,001). PCFS, MIF, Handgrip, 10 MWT e DASS-21 domínio ansiedade apresentam tendências de melhora. Conclusão: O programa melhora a dor, mobilidade e ansiedade em pacientes com COVID longa.

Rehabilitation of patients after COVID-19 recovery: An experience at the Physical and Rehabilitation Medicine Institute and Lucy Montoro Rehabilitation Institute.

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.

Rehabilitation of patients after COVID-19 recovery: an experience at the physical and rehabilitation medicine Institute and Lucy Montoro Rehabilitation Institute

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.

Osteoporosis evaluation through full developed speckle imaging.

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 and mandible 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.

QUANTIFICATION OF RETINAL CAPILLARY NONPERFUSION IN DIABETICS USING WIDE-FIELD OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

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.

Retinal Nonperfusion Relationship to Arteries or Veins Observed on Widefield Optical Coherence Tomography Angiography in Diabetic Retinopathy.

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 × 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 venous-adjacent 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 = -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.

Controlling for Artifacts in Widefield Optical Coherence Tomography Angiography Measurements of Non-Perfusion Area.

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-OCT-signal 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.

Focus Tracking System for Femtosecond Laser Machining using Low Coherence Interferometry.

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.

Soldering mask laser removal from printed circuit boards aiming copper recycling.

Management of waste of electric and electronic equipment (WEEE) is a key issue for modern societies; furthermore, it contains valuable materials that can be recycled, especially in printed circuit boards (PCB), which have approximately one-third of their weight in copper. In this study we demonstrated the use of laser to strip the covering soldering mask on PCB's, thus exposing the copper underneath so that extraction techniques may take place. Using a Q-Switched Nd:YAG laser operating at 1064nm and 532nm we tested the procedure under different energy conditions. The laser stripping of the soldering mask was achieved with satisfactory results by irradiation with 225mJ at 1064nm. However, when using similar parameters at 532nm the process of the coating ejection was not promoted properly, leading to a faulty detachment. Infrared laser PCB stripping presents itself to be technically viable and environmental friendly, since it uses no chemicals inputs, offering one more option to WEEE treatment and recycling.

Antimicrobial photodynamic therapy combined to periodontal treatment: Experimental model.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) has been used as an adjuvant treatment for periodontitis. It combines a photosensitizer with a light source to induce reactive oxygen species and kill microbial cells. PpNetNI is a protoporphyrin derivative, and it has a chemical binding site at biofilm and great affinity to microbial cells. The aim of this study was to investigate the effects of aPDT as an adjuvant treatment for periodontitis. METHODS: Thirty healthy male rats Wistar (Rattus norvegicus) were used in this study (Approved by UNINOVE Ethical committee AN0029/2015). Periodontitis was induced by placing a cotton ligature around the first mandibular molar in a subgengival position. The contralateral mandibular first molar received neither a ligature nor any treatment, and was used as a control. After 7 days, the ligature was removed and all animals received scaling and root planing (SRP) and were divided according to the following treatments: SRP group (received SRP and irrigation with PpNetNI, 10µM) and aPDT group (PpNetNI 10µM followed by LED irradiation). aPDT was performed with a LED (630nm) with an output power of 400mW (fluence-rate 200mW/cm2; fluence 18J/cm2). Rats were euthanized at 24h, 48h and 7days postoperatively. The area of bone loss in vestibular region of the first molar was evaluated by Optical Coherence Tomography (OCT, THORLABS LTD., Ely, UK). Data were analyzed statistically (ANOVA and Tukey tests, p<0.05). RESULTS: The animals treated by aPDT showed bone gain of approximately 30% compared to the SRP group following 7days from the treatment. CONCLUSION: aPDT promoted bone recovery 7days after periodontal intervention.

Optical coherence tomography for blood glucose monitoring in vitro through spatial and temporal approaches.

As diabetes causes millions of deaths worldwide every year, new methods for blood glucose monitoring are in demand. Noninvasive approaches may increase patient adherence to treatment while reducing costs, and optical coherence tomography (OCT) may be a feasible alternative to current invasive diagnostics. This study presents two methods for blood sugar monitoring with OCT in vitro. The first, based on spatial statistics, exploits changes in the light total attenuation coefficient caused by different concentrations of glucose in the sample using a 930-nm commercial OCT system. The second, based on temporal analysis, calculates differences in the decorrelation time of the speckle pattern in the OCT signal due to blood viscosity variations with the addition of glucose with data acquired by a custom built Swept Source 1325-nm OCT system. Samples consisted of heparinized mouse blood, phosphate buffer saline, and glucose. Additionally, further samples were prepared by diluting mouse blood with isotonic saline solution to verify the effect of higher multiple scattering components on the ability of the methods to differentiate glucose levels. Our results suggest a direct relationship between glucose concentration and both decorrelation rate and attenuation coefficient, with our systems being able to detect changes of 65 mg/dL in glucose concentration.