Retinal organoids from human-induced pluripotent stem cells: From studying retinal dystrophies to early diagnosis of Alzheimer's and Parkinson's disease.

Human-induced pluripotent stem cells (hiPSCs) have provided new methods to study neurodegenerative diseases. In addition to their wide application in neuronal disorders, hiPSCs technology can also encompass specific conditions, such as inherited retinal dystrophies. The possibility of evaluating alterations related to retinal disorders in 3D organoids increases the truthfulness of in vitro models. Moreover, both Alzheimer's (AD) and Parkinson's disease (PD) have been described as causing early retinal alterations, generating beta-amyloid protein accumulation, or affecting dopaminergic amacrine cells. This review addresses recent advances and future perspectives obtained from in vitro modeling of retinal diseases, focusing on retinitis pigmentosa (RP). Additionally, we depicted the possibility of evaluating changes related to AD and PD in retinal organoids obtained from potential patients long before the onset of the disease, constituting a valuable tool in early diagnosis. With this, we pointed out prospects in the study of retinal dystrophies and early diagnosis of AD and PD.

An automated approach for real-time informative frames classification in laryngeal endoscopy using deep learning.

PURPOSE: Informative image selection in laryngoscopy has the potential for improving automatic data extraction alone, for selective data storage and a faster review process, or in combination with other artificial intelligence (AI) detection or diagnosis models. This paper aims to demonstrate the feasibility of AI in providing automatic informative laryngoscopy frame selection also capable of working in real-time providing visual feedback to guide the otolaryngologist during the examination. METHODS: Several deep learning models were trained and tested on an internal dataset (n = 5147 images) and then tested on an external test set (n = 646 images) composed of both white light and narrow band images. Four videos were used to assess the real-time performance of the best-performing model. RESULTS: ResNet-50, pre-trained with the pretext strategy, reached a precision = 95% vs. 97%, recall = 97% vs, 89%, and the F1-score = 96% vs. 93% on the internal and external test set respectively (p = 0.062). The four testing videos are provided in the supplemental materials. CONCLUSION: The deep learning model demonstrated excellent performance in identifying diagnostically relevant frames within laryngoscopic videos. With its solid accuracy and real-time capabilities, the system is promising for its development in a clinical setting, either autonomously for objective quality control or in conjunction with other algorithms within a comprehensive AI toolset aimed at enhancing tumor detection and diagnosis.

EMG-driven control in lower limb prostheses: a topic-based systematic review.

BACKGROUND: The inability of users to directly and intuitively control their state-of-the-art commercial prosthesis contributes to a low device acceptance rate. Since Electromyography (EMG)-based control has the potential to address those inabilities, research has flourished on investigating its incorporation in microprocessor-controlled lower limb prostheses (MLLPs). However, despite the proposed benefits of doing so, there is no clear explanation regarding the absence of a commercial product, in contrast to their upper limb counterparts. OBJECTIVE AND METHODOLOGIES: This manuscript aims to provide a comparative overview of EMG-driven control methods for MLLPs, to identify their prospects and limitations, and to formulate suggestions on future research and development. This is done by systematically reviewing academical studies on EMG MLLPs. In particular, this review is structured by considering four major topics: (1) type of neuro-control, which discusses methods that allow the nervous system to control prosthetic devices through the muscles; (2) type of EMG-driven controllers, which defines the different classes of EMG controllers proposed in the literature; (3) type of neural input and processing, which describes how EMG-driven controllers are implemented; (4) type of performance assessment, which reports the performance of the current state of the art controllers. RESULTS AND CONCLUSIONS: The obtained results show that the lack of quantitative and standardized measures hinders the possibility to analytically compare the performances of different EMG-driven controllers. In relation to this issue, the real efficacy of EMG-driven controllers for MLLPs have yet to be validated. Nevertheless, in anticipation of the development of a standardized approach for validating EMG MLLPs, the literature suggests that combining multiple neuro-controller types has the potential to develop a more seamless and reliable EMG-driven control. This solution has the promise to retain the high performance of the currently employed non-EMG-driven controllers for rhythmic activities such as walking, whilst improving the performance of volitional activities such as task switching or non-repetitive movements. Although EMG-driven controllers suffer from many drawbacks, such as high sensitivity to noise, recent progress in invasive neural interfaces for prosthetic control (bionics) will allow to build a more reliable connection between the user and the MLLPs. Therefore, advancements in powered MLLPs with integrated EMG-driven control have the potential to strongly reduce the effects of psychosomatic conditions and musculoskeletal degenerative pathologies that are currently affecting lower limb amputees.

Transoral laser microsurgery: feasibility of a new exoscopic HD-3D system coupled with free beam or fiber laser.

In the last decades, new technological devices and instruments have been developed to overcome the technical limits of transoral laser microsurgery. The recent introduction of 3D endoscopy seems to be a promising tool in the field of diagnostic and operative laryngology as an alternative to the traditional microlaryngoscopy. Our work aims to present a novel transoral microsurgical setting that expands the use of exoscopic systems (in this case the VITOM® 3D-HD) as an alternative to the standard operating microscope. A customized support arm and an adaptor to firmly connect the VITOM® 3D-HD camera to the laser micromanipulator were specially designed. This setup was used as an alternative to the standard operating microscope in a cohort of 17 patients affected by suspicious early to intermediate pharyngo-laryngeal neoplasms. A historical cohort of patients treated with the traditional setting and matching the same inclusion criteria was used as a reference for the duration of surgical procedures. The surgical procedures comprised 7 cordectomies, 2 endoscopic partial supraglottic laryngectomies, 4 tongue base resections, and 4 lateral oropharyngectomies or hypopharyngectomies. In 6 cases (35%), a simultaneous neck dissection was performed. The low rate of positive deep (6%) or superficial (12%) margins reinforced the safety of this platform, and the results obtained in terms of operating time were comparable to the control group (p > 0.05), which confirms the feasibility of the system. Our surgical setting setup is a convincing alternative to traditional transoral laser microsurgery for early to intermediate pharyngo-laryngeal neoplasms. The main advantages of this system are comfortable ergonomics for the first surgeon and a potential benefit in terms of teaching if applied in university hospitals, since the entire surgical team can view the same surgical 3D-HD view of the first operator. Further work is still needed to objectively compare the traditional and new technique, and to validate our preliminary clinical findings.

Use of Artificial Intelligence as an Innovative Method for Liver Graft Macrosteatosis Assessment.

The worldwide implementation of a liver graft pool using marginal livers (ie, grafts with a high risk of technical complications and impaired function or with a risk of transmitting infection or malignancy to the recipient) has led to a growing interest in developing methods for accurate evaluation of graft quality. Liver steatosis is associated with a higher risk of primary nonfunction, early graft dysfunction, and poor graft survival rate. The present study aimed to analyze the value of artificial intelligence (AI) in the assessment of liver steatosis during procurement compared with liver biopsy evaluation. A total of 117 consecutive liver grafts from brain-dead donors were included and classified into 2 cohorts: ≥30 versus <30% hepatic steatosis. AI analysis required the presence of an intraoperative smartphone liver picture as well as a graft biopsy and donor data. First, a new algorithm arising from current visual recognition methods was developed, trained, and validated to obtain automatic liver graft segmentation from smartphone images. Second, a fully automated texture analysis and classification of the liver graft was performed by machine-learning algorithms. Automatic liver graft segmentation from smartphone images achieved an accuracy (Acc) of 98%, whereas the analysis of the liver graft features (cropped picture and donor data) showed an Acc of 89% in graft classification (≥30 versus <30%). This study demonstrates that AI has the potential to assess steatosis in a handy and noninvasive way to reliably identify potential nontransplantable liver grafts and to avoid improper graft utilization.

Learning-based keypoint registration for fetoscopic mosaicking.

PURPOSE: In twin-to-twin transfusion syndrome (TTTS), abnormal vascular anastomoses in the monochorionic placenta can produce uneven blood flow between the two fetuses. In the current practice, TTTS is treated surgically by closing abnormal anastomoses using laser ablation. This surgery is minimally invasive and relies on fetoscopy. Limited field of view makes anastomosis identification a challenging task for the surgeon. METHODS: To tackle this challenge, we propose a learning-based framework for in vivo fetoscopy frame registration for field-of-view expansion. The novelties of this framework rely on a learning-based keypoint proposal network and an encoding strategy to filter (i) irrelevant keypoints based on fetoscopic semantic image segmentation and (ii) inconsistent homographies. RESULTS: We validate our framework on a dataset of six intraoperative sequences from six TTTS surgeries from six different women against the most recent state-of-the-art algorithm, which relies on the segmentation of placenta vessels. CONCLUSION: The proposed framework achieves higher performance compared to the state of the art, paving the way for robust mosaicking to provide surgeons with context awareness during TTTS surgery.

A novel affordable user interface for robotic surgery training: design, development and usability study.

Introduction: The use of robotic systems in the surgical domain has become groundbreaking for patients and surgeons in the last decades. While the annual number of robotic surgical procedures continues to increase rapidly, it is essential to provide the surgeon with innovative training courses along with the standard specialization path. To this end, simulators play a fundamental role. Currently, the high cost of the leading VR simulators limits their accessibility to educational institutions. The challenge lies in balancing high-fidelity simulation with cost-effectiveness; however, few cost-effective options exist for robotic surgery training. Methods: This paper proposes the design, development and user-centered usability study of an affordable user interface to control a surgical robot simulator. It consists of a cart equipped with two haptic interfaces, a VR visor and two pedals. The simulations were created using Unity, which offers versatility for expanding the simulator to more complex scenes. An intuitive teleoperation control of the simulated robotic instruments is achieved through a high-level control strategy. Results and Discussion: Its affordability and resemblance to real surgeon consoles make it ideal for implementing robotic surgery training programs in medical schools, enhancing accessibility to a broader audience. This is demonstrated by the results of an usability study involving expert surgeons who use surgical robots regularly, expert surgeons without robotic surgery experience, and a control group. The results of the study, which was based on a traditional Peg-board exercise and Camera Control task, demonstrate the simulator's high usability and intuitive control across diverse user groups, including those with limited experience. This offers evidence that this affordable system is a promising solution for expanding robotic surgery training.

Real-Time Laryngeal Cancer Boundaries Delineation on White Light and Narrow-Band Imaging Laryngoscopy with Deep Learning.

OBJECTIVE: To investigate the potential of deep learning for automatically delineating (segmenting) laryngeal cancer superficial extent on endoscopic images and videos. METHODS: A retrospective study was conducted extracting and annotating white light (WL) and Narrow-Band Imaging (NBI) frames to train a segmentation model (SegMENT-Plus). Two external datasets were used for validation. The model's performances were compared with those of two otolaryngology residents. In addition, the model was tested on real intraoperative laryngoscopy videos. RESULTS: A total of 3933 images of laryngeal cancer from 557 patients were used. The model achieved the following median values (interquartile range): Dice Similarity Coefficient (DSC) = 0.83 (0.70-0.90), Intersection over Union (IoU) = 0.83 (0.73-0.90), Accuracy = 0.97 (0.95-0.99), Inference Speed = 25.6 (25.1-26.1) frames per second. The external testing cohorts comprised 156 and 200 images. SegMENT-Plus performed similarly on all three datasets for DSC (p = 0.05) and IoU (p = 0.07). No significant differences were noticed when separately analyzing WL and NBI test images on DSC (p = 0.06) and IoU (p = 0.78) and when analyzing the model versus the two residents on DSC (p = 0.06) and IoU (Senior vs. SegMENT-Plus, p = 0.13; Junior vs. SegMENT-Plus, p = 1.00). The model was then tested on real intraoperative laryngoscopy videos. CONCLUSION: SegMENT-Plus can accurately delineate laryngeal cancer boundaries in endoscopic images, with performances equal to those of two otolaryngology residents. The results on the two external datasets demonstrate excellent generalization capabilities. The computation speed of the model allowed its application on videolaryngoscopies simulating real-time use. Clinical trials are needed to evaluate the role of this technology in surgical practice and resection margin improvement. LEVEL OF EVIDENCE: III Laryngoscope, 134:2826-2834, 2024.

Placental vessel segmentation and registration in fetoscopy: Literature review and MICCAI FetReg2021 challenge findings.

Fetoscopy laser photocoagulation is a widely adopted procedure for treating Twin-to-Twin Transfusion Syndrome (TTTS). The procedure involves photocoagulation pathological anastomoses to restore a physiological blood exchange among twins. The procedure is particularly challenging, from the surgeon's side, due to the limited field of view, poor manoeuvrability of the fetoscope, poor visibility due to amniotic fluid turbidity, and variability in illumination. These challenges may lead to increased surgery time and incomplete ablation of pathological anastomoses, resulting in persistent TTTS. Computer-assisted intervention (CAI) can provide TTTS surgeons with decision support and context awareness by identifying key structures in the scene and expanding the fetoscopic field of view through video mosaicking. Research in this domain has been hampered by the lack of high-quality data to design, develop and test CAI algorithms. Through the Fetoscopic Placental Vessel Segmentation and Registration (FetReg2021) challenge, which was organized as part of the MICCAI2021 Endoscopic Vision (EndoVis) challenge, we released the first large-scale multi-center TTTS dataset for the development of generalized and robust semantic segmentation and video mosaicking algorithms with a focus on creating drift-free mosaics from long duration fetoscopy videos. For this challenge, we released a dataset of 2060 images, pixel-annotated for vessels, tool, fetus and background classes, from 18 in-vivo TTTS fetoscopy procedures and 18 short video clips of an average length of 411 frames for developing placental scene segmentation and frame registration for mosaicking techniques. Seven teams participated in this challenge and their model performance was assessed on an unseen test dataset of 658 pixel-annotated images from 6 fetoscopic procedures and 6 short clips. For the segmentation task, overall baseline performed was the top performing (aggregated mIoU of 0.6763) and was the best on the vessel class (mIoU of 0.5817) while team RREB was the best on the tool (mIoU of 0.6335) and fetus (mIoU of 0.5178) classes. For the registration task, overall the baseline performed better than team SANO with an overall mean 5-frame SSIM of 0.9348. Qualitatively, it was observed that team SANO performed better in planar scenarios, while baseline was better in non-planner scenarios. The detailed analysis showed that no single team outperformed on all 6 test fetoscopic videos. The challenge provided an opportunity to create generalized solutions for fetoscopic scene understanding and mosaicking. In this paper, we present the findings of the FetReg2021 challenge, alongside reporting a detailed literature review for CAI in TTTS fetoscopy. Through this challenge, its analysis and the release of multi-center fetoscopic data, we provide a benchmark for future research in this field.

Towards OCT-Guided Endoscopic Laser Surgery-A Review.

Optical Coherence Tomography (OCT) is an optical imaging technology occupying a unique position in the resolution vs. imaging depth spectrum. It is already well established in the field of ophthalmology, and its application in other fields of medicine is growing. This is motivated by the fact that OCT is a real-time sensing technology with high sensitivity to precancerous lesions in epithelial tissues, which can be exploited to provide valuable information to clinicians. In the prospective case of OCT-guided endoscopic laser surgery, these real-time data will be used to assist surgeons in challenging endoscopic procedures in which high-power lasers are used to eradicate diseases. The combination of OCT and laser is expected to enhance the detection of tumors, the identification of tumor margins, and ensure total disease eradication while avoiding damage to healthy tissue and critical anatomical structures. Therefore, OCT-guided endoscopic laser surgery is an important nascent research area. This paper aims to contribute to this field with a comprehensive review of state-of-the-art technologies that may be exploited as the building blocks for achieving such a system. The paper begins with a review of the principles and technical details of endoscopic OCT, highlighting challenges and proposed solutions. Then, once the state of the art of the base imaging technology is outlined, the new OCT-guided endoscopic laser surgery frontier is reviewed. Finally, the paper concludes with a discussion on the constraints, benefits and open challenges associated with this new type of surgical technology.

Toward a navigation framework for fetoscopy.

PURPOSE: Fetoscopic laser photocoagulation of placental anastomoses is the most effective treatment for twin-to-twin transfusion syndrome (TTTS). A robust mosaic of placenta and its vascular network could support surgeons' exploration of the placenta by enlarging the fetoscope field-of-view. In this work, we propose a learning-based framework for field-of-view expansion from intra-operative video frames. METHODS: While current state of the art for fetoscopic mosaicking builds upon the registration of anatomical landmarks which may not always be visible, our framework relies on learning-based features and keypoints, as well as robust transformer-based image-feature matching, without requiring any anatomical priors. We further address the problem of occlusion recovery and frame relocalization, relying on the computed features and their descriptors. RESULTS: Experiments were conducted on 10 in-vivo TTTS videos from two different fetal surgery centers. The proposed framework was compared with several state-of-the-art approaches, achieving higher [Formula: see text] on 7 out of 10 videos and a success rate of [Formula: see text] in occlusion recovery. CONCLUSION: This work introduces a learning-based framework for placental mosaicking with occlusion recovery from intra-operative videos using a keypoint-based strategy and features. The proposed framework can compute the placental panorama and recover even in case of camera tracking loss where other methods fail. The results suggest that the proposed framework has large potential to pave the way to creating a surgical navigation system for TTTS by providing robust field-of-view expansion.

Artificial Intelligence for Upper Aerodigestive Tract Endoscopy and Laryngoscopy: A Guide for Physicians and State-of-the-Art Review.

OBJECTIVE: The endoscopic and laryngoscopic examination is paramount for laryngeal, oropharyngeal, nasopharyngeal, nasal, and oral cavity benign lesions and cancer evaluation. Nevertheless, upper aerodigestive tract (UADT) endoscopy is intrinsically operator-dependent and lacks objective quality standards. At present, there has been an increased interest in artificial intelligence (AI) applications in this area to support physicians during the examination, thus enhancing diagnostic performances. The relative novelty of this research field poses a challenge both for the reviewers and readers as clinicians often lack a specific technical background. DATA SOURCES: Four bibliographic databases were searched: PubMed, EMBASE, Cochrane, and Google Scholar. REVIEW METHODS: A structured review of the current literature (up to September 2022) was performed. Search terms related to topics of AI, machine learning (ML), and deep learning (DL) in UADT endoscopy and laryngoscopy were identified and queried by 3 independent reviewers. Citations of selected studies were also evaluated to ensure comprehensiveness. CONCLUSIONS: Forty-one studies were included in the review. AI and computer vision techniques were used to achieve 3 fundamental tasks in this field: classification, detection, and segmentation. All papers were summarized and reviewed. IMPLICATIONS FOR PRACTICE: This article comprehensively reviews the latest developments in the application of ML and DL in UADT endoscopy and laryngoscopy, as well as their future clinical implications. The technical basis of AI is also explained, providing guidance for nonexpert readers to allow critical appraisal of the evaluation metrics and the most relevant quality requirements.

Electric Bioimpedance Sensing for the Detection of Head and Neck Squamous Cell Carcinoma.

The early detection of head and neck squamous cell carcinoma (HNSCC) is essential to improve patient prognosis and enable organ and function preservation treatments. The objective of this study is to assess the feasibility of using electrical bioimpedance (EBI) sensing technology to detect HNSCC tissue. A prospective study was carried out analyzing tissue from 46 patients undergoing surgery for HNSCC. The goal was the correct identification of pathologic tissue using a novel needle-based EBI sensing device and AI-based classifiers. Considering the data from the overall patient cohort, the system achieved accuracies between 0.67 and 0.93 when tested on tissues from the mucosa, skin, muscle, lymph node, and cartilage. Furthermore, when considering a patient-specific setting, the accuracy range increased to values between 0.82 and 0.95. This indicates that more reliable results may be achieved when considering a tissue-specific and patient-specific tissue assessment approach. Overall, this study shows that EBI sensing may be a reliable technology to distinguish pathologic from healthy tissue in the head and neck region. This observation supports the continuation of this research on the clinical use of EBI-based devices for early detection and margin assessment of HNSCC.

Engineering and Development of a Tissue Model for the Evaluation of Microneedle Penetration Ability, Drug Diffusion, Photothermal Activity, and Ultrasound Imaging: A Promising Surrogate to Ex Vivo and In Vivo Tissues.

Driven by regulatory authorities and the ever-growing demands from industry, various artificial tissue models have been developed. Nevertheless, there is no model to date that is capable of mimicking the biomechanical properties of the skin whilst exhibiting the hydrophilicity/hydrophobicity properties of the skin layers. As a proof-of-concept study, tissue surrogates based on gel and silicone are fabricated for the evaluation of microneedle penetration, drug diffusion, photothermal activity, and ultrasound bioimaging. The silicone layer aims to imitate the stratum corneum while the gel layer aims to mimic the water-rich viable epidermis and dermis present in in vivo tissues. The diffusion of drugs across the tissue model is assessed, and the results reveal that the proposed tissue model shows similar behavior to a cancerous kidney. In place of typical in vitro aqueous solutions, this model can also be employed for evaluating the photoactivity of photothermal agents since the tissue model shows a similar heating profile to skin of mice when irradiated with near-infrared laser. In addition, the designed tissue model exhibits promising results for biomedical applications in optical coherence tomography and ultrasound imaging. Such a tissue model paves the way to reduce the use of animals testing in research whilst obviating ethical concerns.

[From community pharmacies to big pharmacy chains: private provision of medicines, health system, and financialization of the Brazilian retail pharmacy market]. / Das farmácias comunitárias às grandes redes: provisão privada de medicamentos, sistema de saúde e financeirização no varejo farmacêutico brasileiro.

The provision of medicines in Brazil is marked by the predominance of private expenditures and supply in pharmacies and by the historically liberal regulation of retail drug sales. The first two decades of the 21st century witnessed the expansion and concentration of the retail pharmaceutical sector and growing financialization of the health sector. The article analyzes the characteristics of financialization of Brazilian retail pharmaceutical companies, considering the following three crosscutting dimensions: ownership structure, financial/accounting, and political. Quantitative and qualitative data from various sources were analyzed including ownsership and account informations of the ten biggest Brazilian retail pharmacies chains and political action of four business associations. The information collected was stored in the source project database. The ownership structure dimension revealed verticalization, diversification, capitalization via financial and shareholding operations, intensification of mergers and acquisitions, opening of pharmacy branches, entry of investors, and changes in internal management and organization. The financial/accounting dimension revealed an increase in size (revenues, assets, net worth) and good performance (return on equity capital, capital turnover, and third-party capital) of the networks compared to Brazilian companies and health companies. The policy arena revealed both clashes and collaborations between representative associations and government (Executive, Legislative, and Judiciary), depending on the issue, with outcomes that were generally favorable to the pharmaceutical sector and leadership by the Brazilian Association of Pharmacy and Drugstore Networks (Abrafarma). The financialization of the retail pharmaceutical companies' accumulation pattern and the strengthening of their political action proved relevant for understanding the changes in the provision of medicines and in the pharmaceutical market.

No Brasil a provisão de medicamentos é marcada pelo predomínio dos gastos e da oferta privada em farmácias e pela regulação historicamente liberal sobre a comercialização. Nos anos 2000 e 2010 houve expansão e concentração do varejo farmacêutico e crescente financeirização no setor saúde. O artigo analisa as expressões da financeirização em empresas do varejo farmacêutico brasileiro considerando três dimensões transversais: patrimonial, contábil-financeira e política. Foram analisados dados quantitativos e qualitativos de variadas fontes sobre as dimensões patrimonial e contábil das 10 maiores redes de farmácias brasileiras e à dimensão política da ação de quatro entidades representativas do subsetor. As informações coletadas foram reunidas no banco de dados da pesquisa fonte (Banco de Dados sobre Empresariamento na Saúde - BDES). Na dimensão patrimonial, identificou-se verticalização, diversificação, capitalização por operações financeiras e patrimoniais, intensificação de fusões e aquisições, abertura de farmácias, entrada de investidores, mudanças na gestão e organização interna. Na contábil-financeira, constatou-se aumento de porte (receitas, ativos, patrimônio) e bom desempenho (retorno sobre capital próprio, giro do ativo e capitais de terceiros) das redes em comparação à empresas brasileiras e da saúde. Na política houve embates e colaborações entre entidades e o poder público (Executivo, Legislativo e Judiciário) a depender da pauta, com desfechos geralmente favoráveis ao subsetor e protagonismo da Associação Brasileira de Farmácias e Drogarias (Abrafarma). A financeirização do padrão de acumulação de empresas do varejo farmacêutico e o fortalecimento de sua atuação política se mostraram relevantes para compreensão das mudanças na provisão de medicamentos e no setor farmacêutico.

En Brasil la provisión de medicamentos está marcada por el predominio de los gastos y oferta privada en farmacias, así como por la regulación históricamente liberal sobre su comercialización. En los años 2000 y 2010 hubo una expansión y concentración de la red minorista farmacéutica y una creciente financiarización en el sector salud. El artículo analiza las expresiones de la financiarización en empresas de la red minorista farmacéutica brasileña, considerando tres dimensiones transversales: patrimonial, contable-financiera y política. Se analizaron datos cuantitativos y cualitativos de variadas fuentes, reunidos en el banco de datos del estudio fuente, relacionados con las dimensiones patrimonial y contable de las diez mayores redes de farmacias brasileñas, y con la dimensión de la actuación política de cuatro entidades representativas del subsector. En la dimensión patrimonial, se identificaron: verticalización, diversificación, capitalización por operaciones financieras y patrimoniales, intensificación de fusiones y adquisiciones, apertura de farmacias, entrada de inversores, cambios en la gestión y organización interna. En la contable-financiera, se constató un aumento de tamaño (ingresos, activos, patrimonio) y buen desempeño (rendimiento sobre capital propio, rotación del activo y capitales de terceros) de las redes, en comparación con empresas brasileñas y de salud. En política hubo enfrentamientos y colaboraciones entre entidades y poder público (Ejecutivo, Legislativo y Judicial) dependiendo de la agenda de cada uno, con desenlaces generalmente favorables al subsector y protagonismo de la Asociación Brasileña de Farmacias y Droguerías (Abrafarma). La financiarización del patrón de acumulación de empresas en la red minorista farmacéutica y el fortalecimiento de su actuación política fueron relevantes para la comprensión de los cambios en la provisión de medicamentos y en el sector farmacéutico.

[Financialization, accumulation, and shareholding changes in companies and corporate groups in the Brazilian health sector]. / Financeirização, acumulação e mudanças patrimoniais em empresas e grupos econômicos do setor saúde no Brasil.

This study aims to analyze the shareholding dimension of changes in companies and corporate groups in the Brazilian health sector from 2008 to 2017. The idea was to understand the strategies of accumulation in a context of financialization, defined as a systemic pattern of wealth in contemporary capitalism. The shareholding changes were submitted to descriptive and exploratory analysis based on different sources. We studied 58 companies from the subsectors of health plans, pharmacies, hospitals, diagnostics, pharmaceutical industry, and social organizations. Data were collected on the legal structure, ownership, and control, equity operations, and economic and patient care activities. Despite the heterogeneity of the companies and their strategies, the results point to an increase in the presence of domestic and international investors, changes in internal organization, capital, financing, and diversification of activities. The companies that stood out were actively pursuing capitalization via foreign investments, purchase and share of assets and shares, and mergers and acquisitions, accelerating the process of expansion, accumulation, and shareholding and financial appreciation. The result is an increase in capital flows and growing integration of economic and patient care structures in the Brazilian health sector with financial circuits, thereby linking peripheral intermediate companies to an expanded process of accumulation under financial dominance. The findings corroborate striking aspects of corporate dynamics in financialization that increasingly influence health systems in Brazil and the world.

O objetivo deste trabalho é analisar a dimensão patrimonial de mudanças em empresas e grupos econômicos do setor saúde no Brasil entre 2008 e 2017. Busca-se compreender as estratégias de acumulação em um contexto de financeirização, compreendida como padrão sistêmico da riqueza no capitalismo contemporâneo. As mudanças patrimoniais foram analisadas de forma descritiva e exploratória a partir de diferentes fontes. Foram estudadas 58 empresas dos subsetores de planos de saúde, farmácias, hospitais, diagnóstico, indústria farmacêutica e organizações sociais. Foram coletados dados sobre forma jurídica, propriedade e controle; operações patrimoniais; atividades econômicas e assistenciais. A despeito da heterogeneidade das empresas e suas estratégias, os resultados apontam o aumento da presença de investidores nacionais e internacionais, mudanças na organização interna, na estrutura do capital, no financiamento e diversificação de atividades. As que mais se destacam buscaram ativamente a capitalização a partir de investimentos externos, compra e venda de ativos e ações, fusões e aquisições aceleram o processo de expansão, acumulação e valorização patrimonial-financeira. O resultado é o aumento do fluxo de capitais e a crescente integração das estruturas econômicas e assistenciais do setor saúde brasileiro aos circuitos financeiros, tornando as empresas intermediárias periféricas articuladas a um processo ampliado de acumulação sob dominância financeira. Os achados convergem com aspectos marcantes da dinâmica das corporações na financeirização, que influenciam cada vez mais os sistemas de saúde no Brasil e do mundo.

El objetivo de este trabajo es analizar la dimensión patrimonial de cambios en empresas y grupos económicos del sector salud en Brasil entre 2008 y 2017. Se busca comprender las estrategias de acumulación en un contexto de financiarización, comprendida como un patrón sistémico de la riqueza en el capitalismo contemporáneo. Los cambios patrimoniales fueron analizados de forma descriptiva y exploratoria a partir de diferentes fuentes. Se estudiaron 58 empresas de los subsectores de planes de salud, farmacias, hospitales, diagnóstico, industria farmacéutica y organizaciones sociales. Se recogieron datos sobre forma jurídica, propriedad y control; operaciones patrimoniales; actividades económicas y asistenciales. A pesar de la heterogeneidad de las empresas y sus estrategias, los resultados apuntan el aumento de la presencia de inversores nacionales e internacionales, cambios en la organización interna, estructura del capital, financiación y diversificación de actividades. Las que más se destacan buscaron activamente la capitalización a partir de inversiones externas, compra y venta de activos y acciones, fusiones y adquisiciones aceleraron el proceso de expansión, acumulación y valorización patrimonial-financiera. El resultado es el aumento del flujo de capitales y la creciente integración de las estructuras económicas y asistenciales del sector salud brasileño en los circuitos financieros, haciendo que las empresas intermediarias periféricas se coordinaran con un proceso ampliado de acumulación, auspiciado por el dominio financiero. Los resultados convergen con aspectos marcantes de la dinámica de las corporaciones en la financiarización, que influencian cada vez más los sistemas de salud en Brasil y en el mundo.

[Economic crisis and disparities in spending, supply, and use of public and private health services in Brazil from 2011 to 2019]. / Crise econômica e disparidades no gasto, oferta e utilização de serviços públicos e privados de saúde no Brasil no período entre 2011 e 2019.

This study sought to analyze the repercussions of the economic crisis on the public and private sectors of the Brazilian health system and perform a trend analysis of economic and care indicators, based on secondary data from official public sources related to spending, the economic performance of health plans and insurance, and the supply and use of services. The results showed stagnation of public spending on health, as well as reduction of per capita public spending and of access to public health services. On the contrary, in a context of falling income and employment, health plans retained customers, increased revenues, profits, and their care production. The positive performance of companies, before and after the crisis, can be explained by the trend of maintaining public subsidies for the private sector and by financialized business strategies. We conclude that the actions of the Brazilian government during the crisis deepened the restriction of resources to the public sector and favored the expansion of private services, which thus contributed to increase the discrepancy in access to public and private health services in the country.

Buscou-se analisar as repercussões da crise econômica sobre os setores público e privado do sistema de saúde brasileiro e realizar uma análise de tendência de indicadores econômicos e assistenciais, elaborados a partir de dados secundários de fontes públicas oficiais, relacionados ao gasto, ao desempenho econômico de planos e seguros de saúde, à oferta e utilização de serviços. Os resultados demonstraram estagnação do gasto público em saúde, redução do gasto público per capita e do acesso aos serviços públicos de saúde. Contrariamente, em um contexto de queda da renda e do emprego, os planos de saúde mantiveram clientes, ampliaram as receitas, os lucros e a produção assistencial. O desempenho positivo das empresas, antes e a partir da crise, pode ser explicado pela tendência de manutenção de subsídios públicos para o setor privado e pelas estratégias empresariais financeirizadas. Conclui-se que a atuação do Estado brasileiro durante a crise aprofundou a restrição de recursos ao setor público e favoreceu a expansão dos serviços privados, o que contribuiu para aumentar a discrepância no acesso a serviços públicos e privados de saúde no país.

Se pretende analizar las repercusiones de la crisis económica en los sectores público y privado del sistema de salud brasileño y realizar un análisis de tendencia de los indicadores económicos y asistenciales, con base en datos secundarios de fuentes públicas oficiales relacionados con el gasto, el desempeño económico de los planes y seguros de salud, a la oferta y uso de servicios. Los resultados mostraron estancamiento del gasto público en salud, reducción del gasto público per cápita y del acceso a los servicios públicos de salud. Por el contrario, en un contexto de descenso de ingresos y de empleo, los seguros médicos mantuvieron sus clientes, aumentaron los ingresos, las ganancias y la producción asistencial. El buen desempeño de las empresas antes y después de la crisis se debe a la tendencia a mantener los subsidios públicos en el sector privado y a las estrategias empresariales financiarizadas. Se concluye que las acciones del Estado brasileño durante la crisis profundizaron la restricción de recursos al sector público y favorecieron la expansión de los servicios privados, lo que contribuyó a aumentar la discrepancia en el acceso a los servicios de salud públicos y privados en el país.

[Financialization of the health sector in Brazil: theoretical and methodological challenges to the investigation of companies and business groups]. / Financeirização do setor saúde no Brasil: desafios teóricos e metodológicos à investigação de empresas e grupos empresariais.

The article describes the history of the response to the theoretical and methodological challenges in research on companies and corporate groups in the Brazilian health sector that reorganized their shareholding structures, diversified their activities, and expanded their financial operations. Such movements in corporate concentration and expansion were analyzed with an approach to the frame of reference for financialization in contemporary capitalism in the analysis of selected companies and corporate groups. Corporate strategies were classified in three dimensions: shareholding, financial, and accounting structure and influence on the public agenda and the respective indicators orienting the organization of information from diverse sources for companies and corporate groups from 2008 and 2017. The study provides a profile of the intense and complex process of corporate reorganization in the health sector. Still, the study's exploratory design and difficulties in access to information and selection of companies and corporate groups mean that the observations are necessarily preliminary.

O artigo descreve a trajetória percorrida para responder aos desafios teóricos e metodológicos da pesquisa sobre empresas e grupos empresariais do setor saúde no Brasil que reorganizaram suas estruturas societárias, diversificaram atividades e ampliaram operações financeiras. Tais movimentos de concentração e expansão empresarial foram analisados mediante a aproximação do referencial da financeirização do capitalismo contemporâneo à análise de empresas e grupos empresariais selecionados. As estratégias empresariais foram classificadas em três dimensões: estrutura patrimonial societária, financeira contábil e influência na agenda pública. Seus respectivos indicadores orientam a organização de informações de distintas fontes para empresas e grupos empresariais no período de 2008 a 2017. O estudo traça um perfil do intenso e complexo processo de reorganização empresarial do setor saúde. Contudo, a natureza exploratória da investigação, bem como as dificuldades de acesso a informações e seleção de empresas e grupos empresariais tornam suas constatações necessariamente provisórias.

El artículo describe la trayectoria recorrida para responder a los desafios teóricos y metodológicos de la investigación sobre empresas y grupos empresariales del sector de salud en Brasil, que reorganizaron sus estructuras societarias, diversificaron actividades y ampliaron operaciones financieras. Tales movimientos de concentración y expansión empresarial fueron analizados mediante la aproximación al marco de referencia de la financiarización del capitalismo contemporáneao, así como al análisis de empresas y grupos empresariales seleccionados. Las estrategias empresariales fueron clasificadas en tres dimensiones: estructura patrimonial societaria, financiera contable e influencia en la agenda pública, así como sus respectivos indicadores que orientan la organización de la información de las distintas fuentes en empresas y grupos empresariales durante el período 2008 a 2017. El estudio traza un perfil del intenso y complejo proceso de reorganización empresarial del sector de salud. No obstante, la naturaleza exploratoria de la investigación, así como las dificultades de acesso a la información, selección de empresas y grupos empresariales convierten sus constataciones en necesariamente provisionales.

Deep Learning Applied to White Light and Narrow Band Imaging Videolaryngoscopy: Toward Real-Time Laryngeal Cancer Detection.

OBJECTIVES: To assess a new application of artificial intelligence for real-time detection of laryngeal squamous cell carcinoma (LSCC) in both white light (WL) and narrow-band imaging (NBI) videolaryngoscopies based on the You-Only-Look-Once (YOLO) deep learning convolutional neural network (CNN). STUDY DESIGN: Experimental study with retrospective data. METHODS: Recorded videos of LSCC were retrospectively collected from in-office transnasal videoendoscopies and intraoperative rigid endoscopies. LSCC videoframes were extracted for training, validation, and testing of various YOLO models. Different techniques were used to enhance the image analysis: contrast limited adaptive histogram equalization, data augmentation techniques, and test time augmentation (TTA). The best-performing model was used to assess the automatic detection of LSCC in six videolaryngoscopies. RESULTS: Two hundred and nineteen patients were retrospectively enrolled. A total of 624 LSCC videoframes were extracted. The YOLO models were trained after random distribution of images into a training set (82.6%), validation set (8.2%), and testing set (9.2%). Among the various models, the ensemble algorithm (YOLOv5s with YOLOv5m-TTA) achieved the best LSCC detection results, with performance metrics in par with the results reported by other state-of-the-art detection models: 0.66 Precision (positive predicted value), 0.62 Recall (sensitivity), and 0.63 mean Average Precision at 0.5 intersection over union. Tests on the six videolaryngoscopies demonstrated an average computation time per videoframe of 0.026 seconds. Three demonstration videos are provided. CONCLUSION: This study identified a suitable CNN model for LSCC detection in WL and NBI videolaryngoscopies. Detection performances are highly promising. The limited complexity and quick computational times for LSCC detection make this model ideal for real-time processing. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:1798-1806, 2022.