COVID-19 Computed tomography patterns in renal replacement therapy patients / Padrões de tomografia computadorizada da COVID-19 em pacientes em terapia renal substitutiva

ABSTRACT Introduction: Lung diseases are common in patients with end stage kidney disease (ESKD), making differential diagnosis with COVID-19 a challenge. This study describes pulmonary chest tomography (CT) findings in hospitalized ESKD patients on renal replacement therapy (RRT) with clinical suspicion of COVID-19. Methods: ESKD individuals referred to emergency department older than 18 years with clinical suspicion of COVID-19 were recruited. Epidemiological baseline clinical information was extracted from electronic health records. Pulmonary CT was classified as typical, indeterminate, atypical or negative. We then compared the CT findings of positive and negative COVID-19 patients. Results: We recruited 109 patients (62.3% COVID-19-positive) between March and December 2020, mean age 60 ± 12.5 years, 43% female. The most common etiology of ESKD was diabetes. Median time on dialysis was 36 months, interquartile range = 12-84. The most common pulmonary lesion on CT was ground glass opacities. Typical CT pattern was more common in COVID-19 patients (40 (61%) vs 0 (0%) in non-COVID-19 patients, p < 0.001). Sensitivity was 60.61% (40/66) and specificity was 100% (40/40). Positive predictive value and negative predictive value were 100% and 62.3%, respectively. Atypical CT pattern was more frequent in COVID-19-negative patients (9 (14%) vs 24 (56%) in COVID-19-positive, p < 0.001), while the indeterminate pattern was similar in both groups (13 (20%) vs 6 (14%), p = 0.606), and negative pattern was more common in COVID-19-negative patients (4 (6%) vs 12 (28%), p = 0.002). Conclusions: In hospitalized ESKD patients on RRT, atypical chest CT pattern cannot adequately rule out the diagnosis of COVID-19.

RESUMO Introdução: Doenças pulmonares são comuns em pacientes com doença renal em estágio terminal (DRET), dificultando o diagnóstico diferencial com COVID-19. Este estudo descreve achados de tomografia computadorizada de tórax (TC) em pacientes com DRET em terapia renal substitutiva (TRS) hospitalizados com suspeita de COVID-19. Métodos: Indivíduos maiores de 18 anos com DRET, encaminhados ao pronto-socorro com suspeita de COVID-19 foram incluídos. Dados clínicos e epidemiológicos foram extraídos de registros eletrônicos de saúde. A TC foi classificada como típica, indeterminada, atípica, negativa. Comparamos achados tomográficos de pacientes com COVID-19 positivos e negativos. Resultados: Recrutamos 109 pacientes (62,3% COVID-19-positivos) entre março e dezembro de 2020, idade média de 60 ± 12,5 anos, 43% mulheres. A etiologia mais comum da DRET foi diabetes. Tempo médio em diálise foi 36 meses, intervalo interquartil = 12-84. A lesão pulmonar mais comum foi opacidades em vidro fosco. O padrão típico de TC foi mais comum em pacientes com COVID-19 (40 (61%) vs. 0 (0%) em pacientes sem COVID-19, p < 0,001). Sensibilidade 60,61% (40/66), especificidade 100% (40/40). Valores preditivos positivos e negativos foram 100% e 62,3%, respectivamente. Padrão atípico de TC foi mais frequente em pacientes COVID-19-negativos (9 (14%) vs. 24 (56%) em COVID-19-positivos, p < 0,001), enquanto padrão indeterminado foi semelhante em ambos os grupos (13 (20%) vs. 6 (14%), p = 0,606), e padrão negativo foi mais comum em pacientes COVID-19-negativos (4 (6%) vs. 12 (28%), p = 0,002). Conclusões: Em pacientes com DRET em TRS hospitalizados, um padrão atípico de TC de tórax não pode excluir adequadamente o diagnóstico de COVID-19.

Incidence of contrast-associated acute kidney injury: a prospective cohort / Incidência de lesão renal aguda associada ao contraste: uma coorte prospectiva

ABSTRACT Introduction: Contrast-associated acute kidney injury (CA-AKI) is a deterioration of kidney function that occurs after the administration of a iodinated contrast medium (ICM). Most studies that defined this phenomenon used older ICMs that were more prone of causing CA-AKI. In the past decade, several articles questioned the true incidence of CA-AKI. However, there is still a paucity of a data about the safety of newer ICM. Objective: To assess the incidence of CA-AKI in hospitalized patients that were exposed to computed tomography (CT) with and without ICM. Methods: Prospective cohort study with 1003 patients who underwent CT in a tertiary hospital from December 2020 through March 2021. All inpatients aged > 18 years who had a CT scan during this period were screened for the study. CA-AKI was defined as a relative increase of serum creatinine of ≥ 50% from baseline or an absolute increase of ≥ 0.3 mg/dL within 18 to 48 hours after the CT. Chi-squared test, Kruskal-Wallis test, and linear regression model with restricted cubic splines were used for statistical analyses. Results: The incidence of CA-AKI was 10.1% in the ICM-exposed group and 12.4% in the control group when using the absolute increase criterion. The creatinine variation from baseline was not significantly different between groups. After adjusting for baseline factors, contrast use did not correlate with worse renal function. Conclusion: The rate of CA-AKI is very low, if present at all, with newer ICMs, and excessive caution regarding contrast use is probably unwarranted.

RESUMO Introdução: Lesão renal aguda associada ao contraste (LRA-AC) é uma deterioração da função renal que ocorre após a administração de meio de contraste iodado (MCI). A maioria dos estudos que definiram esse fenômeno utilizaram MCI mais antigos, mais propensos a causar LRA-AC. Na última década, diversos artigos questionaram a verdadeira incidência de LRA-AC. Entretanto, ainda há escassez de dados sobre a segurança dos MCI mais novos. Objetivo: Avaliar a incidência de LRA-AC em pacientes hospitalizados expostos à tomografia computadorizada (TC) com e sem MCI. Métodos: Estudo de coorte prospectivo com 1.003 pacientes submetidos a TC em hospital terciário, de dezembro/2020 a março/2021. Todos os pacientes internados com idade ≥ 18 anos que realizaram TC nesse período foram selecionados. A LRA-AC foi definida como aumento relativo de creatinina sérica de ≥ 50% em relação ao valor basal ou aumento absoluto de ≥ 0,3 mg/dL dentro de 18 a 48 horas após a TC. Utilizamos o teste qui-quadrado, teste de Kruskal-Wallis e modelo de regressão linear com splines cúbicos restritos para análises estatísticas. Resultados: A incidência de LRA-AC foi 10,1% no grupo exposto ao MCI e 12,4% no grupo controle ao usar o critério de aumento absoluto. A variação da creatinina em relação ao valor basal não foi significativamente diferente entre os grupos. Após ajuste para fatores basais, o uso de contraste não se correlacionou com pior função renal. Conclusão: A taxa de LRA-AC é muito baixa, caso exista, com MCIs mais novos, e a cautela excessiva quanto ao uso de contraste provavelmente não se justifica.

Radiological, histological and clinical side effects of incisor trimming in rabbits.

INTRODUCTION: Incisor malocclusion in rabbits (Oryctolagus cuniculus) is a common clinical problem seen in general practice. Given that the growth rate is about 2 mm per week, a lack of wear quickly leads to feeding difficulties and soft tissue injuries. Therefore, pathologically elongated incisors must be shortened every three to six weeks. The goal of this study was to assess the potential adverse effects on dental and periodontal tissues associated with the three most commonly used trimming methods: nail cutter, diamond-coated cutting disc and diamond burr. The left mandibular incisor of 28 healthy New Zealand rabbits was subjected to four trimmings with one of the three cutting methods. After the fattening period, the mandibles were collected and both mandibular incisors were investigated on dental radiographs, micro-computed tomography scans and histological sections. Dental and periodontal tissue changes were evaluated. This study allowed a more accurate statement of the potential short-term adverse effects of the three trimming methods. At the clinical level, the nail cutter caused the formation of an irregular occlusal surface with sharp edges. Both engine-drive methods allowed the attainment of a smooth surface but the disc was less accurate. Histological evaluation revealed that the primary modifications, including coronal fractures, periodontal ligament widening and inflammation, reparative osteodentine, paracementosis and biofilm accumulation, were found in the nail cutter group.

INTRODUCTION: La malocclusion des incisives chez le lapin (Oryctolagus cuniculus) est un problème clinique courant en médecine générale. Étant donné que le taux de croissance est d'environ 2 mm par semaine, un manque d'usure entraîne rapidement des difficultés d'alimentation et des lésions des tissus mous. Par conséquent, les incisives pathologiquement trop longues doivent être raccourcies toutes les trois à six semaines. L'objectif de cette étude était d'évaluer les effets négatifs potentiels sur les tissus dentaires et parodontaux associés aux trois méthodes de taille les plus couramment utilisées: le coupeongles, le disque de coupe diamanté et la fraise diamantée. L'incisive mandibulaire gauche de 28 lapins néo-zélandais en bonne santé a été soumise à quatre tailles avec l'une des trois méthodes de coupe. Après la période d'engraissement, les mandibules ont été prélevées et les deux incisives mandibulaires ont été examinées sur des radiographies dentaires, des examens micro-tomodensitométriques et des coupes histologiques. Les modifications des tissus dentaires et parodontaux ont été évaluées. Cette étude a permis de mieux cerner les effets indésirables potentiels à court terme des trois méthodes de coupe. Au niveau clinique, le coupe-ongles a entraîné la formation d'une surface occlusale irrégulière avec des bords tranchants. Les deux autres méthodes de taille permettent d'obtenir une surface lisse, mais le disque est moins précis. L'évaluation histologique a révélé que les modifications primaires, y compris les fractures coronaires, l'élargissement et l'inflammation du ligament parodontal, l'ostéodentine réparatrice, la paracémentose et l'accumulation de biofilm, ont été trouvées dans le groupe coupe-ongles.

Prevalence and prognostic meaning of interstitial lung abnormalities in remote CT scans of patients with interstitial lung disease treated with antifibrotic therapy.

OBJECTIVES: To describe the prevalence and characteristics of interstitial lung abnormalities (ILA) in CT scans performed prior to the initiation of antifibrotics in a series of patients with interstitial lung disease (ILD), and to identify characteristics apparent on early CT scans that could help to predict outcomes. METHODS: We conducted a retrospective observational study. The original cohort consisted of 101 patients diagnosed with ILD and treated with antifibrotics in a tertiary hospital. Patients were included if they had a thoracic CT scan performed at least one year before initiation of therapy. They were classified radiologically in three groups: without ILA, with radiological ILA and extensive abnormalities. ILA were classified as subpleural fibrotic, subpleural non-fibrotic and non-subpleural. The initial scan and the latest CT scan performed before treatment were read for assessing progression. The relationship between CT findings of fibrosis and the radiological progression rate and mortality were analyzed. RESULTS: We included 50 patients. Only 1 (2%) had a normal CT scan, 25 (50%) had extensive alterations and 24 (48%) had radiological criteria for ILA, a median of 98.2 months before initiation of antifibrotics, of them 18 (75%) had a subpleural fibrotic pattern. Significant bronchiectasis and obvious honeycombing in the lower zones were associated with shorter survival (p = 0.04). Obvious honeycombing in the lower zones was also significantly (p < 0.05) associated with a faster progression rate. CONCLUSIONS: Fibrotic ILAs are frequent in remote scans of patients with clinically relevant ILD, long before they require antifibrotics. Findings of traction bronchiectasis and honeycombing in the earliest scans, even in asymptomatic patients, are related to mortality and progression later on.

Target sign in COVID-19, radiological interpretation and diagnostic contribution of digital thoracic tomosynthesis.

INTRODUCTION: Our objectives are: To describe the radiological semiology, clinical-analytical features and prognosis related to the target sign (TS) in COVID-19. To determine whether digital thoracic tomosynthesis (DTT) improves the diagnostic ability of radiography. MATERIAL AND METHODS: Retrospective, descriptive, single-centre, case series study, accepted by our ethical committee. Radiological, clinical, analytical and follow-up characteristics of patients with COVID-19 and TS on radiography and DTT between November 2020 and January 2021 were analysed. RESULTS: Eleven TS were collected in 7 patients, median age 35 years, 57% male. All TS presented with a central nodule and a peripheral ring, and in at least 82%, the lung in between was of normal density. All TS were located in peripheral, basal regions and 91% in posterior regions. TS were multiple in 43%. Contiguous TS shared the peripheral ring. Other findings related to pneumonia were associated in 86% of patients. DTT detected 82% more TS than radiography. Only one patient underwent a CT angiography of the pulmonary arteries, positive for acute pulmonary thromboembolism. Seventy-one per cent presented with pleuritic pain. No distinctive laboratory findings or prognostic worsening were detected. CONCLUSIONS: TS in COVID-19 predominates in peripheral and declining regions and can be multiple. Pulmonary thromboembolism was detected in one case. It occurs in young people, frequently with pleuritic pain and does not worsen the prognosis. DTT detects more than 80 % of TS than radiography.

A serial image analysis architecture with positron emission tomography using machine learning combined for the detection of lung cancer.

INTRODUCTION AND OBJECTIVES: Lung cancer is the second type of cancer with the second highest incidence rate and the first with the highest mortality rate in the world. Machine learning through the analysis of imaging tests such as positron emission tomography/computed tomography (PET/CT) has become a fundamental tool for the early and accurate detection of cancer. The objective of this study was to propose an image analysis architecture (PET/CT) ordered in phases through the application of ensemble or combined machine learning methods for the early detection of lung cancer by analyzing PET/CT images. MATERIAL AND METHODS: A retrospective observational study was conducted utilizing a public dataset entitled "A large-scale CT and PET/CT dataset for lung cancer diagnosis." Various imaging modalities, including CT, PET, and fused PET/CT images, were employed. The architecture or framework of this study comprised the following phases: 1. Image loading or collection, 2. Image selection, 3. Image transformation, and 4. Balancing the frequency distribution of image classes. Predictive models for lung cancer detection using PET/CT images included: a) the Stacking model, which used Random Forest and Support Vector Machine (SVM) as base models and complemented them with a logistic regression model, and b) the Boosting model, which employed the Adaptive Boosting (AdaBoost) model for comparison with the Stacking model. Quality metrics used for evaluation included accuracy, precision, recall, and F1-score. RESULTS: This study showed a general performance of 94% with the Stacking method and a general performance of 77% with the Boosting method. CONCLUSIONS: The Stacking method proved to be a model with high performance and quality for lung cancer detection when analyzing PET/CT images.

Checklist: Neck computed tomography in non-traumatic emergencies.

Patients attending the emergency department (ED) with cervical inflammatory/infectious symptoms or presenting masses that may involve the aerodigestive tract or vascular structures require a contrast-enhanced computed tomography (CT) scan of the neck. Its radiological interpretation is hampered by the anatomical complexity and pathophysiological interrelationship between the different component systems in a relatively small area. Recent studies propose a systematic evaluation of the cervical structures, using a 7-item checklist, to correctly identify the pathology and detect incidental findings that may interfere with patient management. As a conclusion, the aim of this paper is to review CT findings in non-traumatic pathology of the neck in the ED, highlighting the importance of a systematic approach in its interpretation and synthesis of a structured, complete, and concise radiological report.

Desplazamiento de los catéteres para bloqueo continuo del nervio supraescapular tras fisioterapia: estudio en cadáveres / Dislodgment of continuous suprascapular nerve block catheters after physiotherapy: A cadaver study

Antecedentes: Los bloqueos continuos de los nervios periféricos son de uso común para el manejo del dolor. Sin embargo, la incidencia de desplazamiento o migración del catéter es dudosa, pudiendo ser infraestimada y no denunciarse. Nuestro objetivo fue evaluar el posicionamiento del extremo del catéter supraescapular antes y después de la manipulación rutinaria y simulada mediante fisioterapia de hombro en un modelo cadavérico anatómico.MétodoSe colocaron 8 catéteres para bloqueo continuo y ecoguiado del nervio supraescapular en cadáveres frescos criopreservados. La tomografía computarizada (TC) confirmó la localización de la punta del catéter tras la inyección de 1ml de medio de contraste. Realizamos una serie de movimientos estandarizados de hombro durante una sesión simulada de fisioterapia de hombro en cadáveres. Tras ello, administramos 1ml de azul de metileno a través de los catéteres, y seguidamente realizamos disecciones para identificar con precisión la localización de las puntas del catéter y compararlas con su localización previa a la «fisioterapia».ResultadosLa imagen de la TC confirmó la localización en todos los casos de los extremos del catéter en la muesca supraescapular. Sin embargo, tras la fisioterapia, se encontró que 2 catéteres (25%) habían migrado y, en especial, uno fue localizado en el músculo supraespinoso y el otro en el músculo trapecio.ConclusiónNuestros hallazgos sugieren que el desplazamiento del catéter puede producirse en cerca del 25% de los casos tras la manipulación mediante fisioterapia simulada. Sin embargo, es necesaria más investigación para determinar la incidencia real de los desplazamientos del catéter en la práctica clínica. (AU)

Background: Continuous peripheral nerve blocks are commonly used for pain management. However, the incidence of catheter dislodgement or migration is unclear, and may be underestimated and underreported. Our objective was to assess suprascapular catheter tip positioning before and after routine simulated shoulder physiotherapy manipulation in an anatomical cadaver model.MethodEight ultrasound-guided continuous suprascapular nerve block catheters were placed in cryopreserved fresh cadavers. Computed tomography (CT) confirmed the location of the catheter tip after injection of 1ml of contrast medium. We performed a series of standardized shoulder movements during a simulated shoulder physiotherapy session in cadavers. Following this, we administered 1ml of methylene blue through the catheters, and then performed anatomical dissections to accurately identify the location of the catheter tips and compare them to their placement prior to the ‘physiotherapy’ResultCT imaging confirmed the location of the catheter tips at the suprascapular notch in all cases. However, following physiotherapy, 2 catheters (25%) were found to have migrated - specifically, 1 was located in the supraspinatus muscle, and the other was located in the trapezius muscle.ConclusionOur findings suggest that catheter dislodgement may occur in approximately 25% of cases following simulated physiotherapy manipulation. However, further research is needed to determine the read incidence of catheter dislodgement in clinical practice. (AU)

Utilidad del estudio del complejo de células ganglionares de la mácula mediante tomografía de coherencia óptica en el diagnóstico de progresión del glaucoma / Study of the ganglion cell complex of the macula by optical coherence tomography in the diagnosis of glaucoma progression

Introducción: El objetivo de este trabajo es valorar la utilidad del estudio del complejo de células ganglionares de la mácula mediante tomografía de coherencia óptica (OCT) para estimar la progresión del glaucoma según su severidad.Material y métodosSe trata de un estudio transversal retrospectivo. Incluye 205 ojos de 131 pacientes con glaucoma o hipertensión ocular seguidos durante una media de 5,7años. Se han analizado los parámetros y las tasas de tres pruebas mediante el software de progresión de cada instrumento: campo visual, OCT en el complejo de células ganglionares de la mácula y en la capa de fibras nerviosas del nervio óptico. Se han evaluado los resultados de cada prueba, la concordancia entre ellas y cómo difieren según el estadio de gravedad.ResultadosEl campo visual clasifica más casos de progresión en el glaucoma moderado-avanzado, mientras que en el glaucoma leve su capacidad está limitada. El OCT de capa de fibras nerviosas del nervio óptico clasifica más casos de progresión en el glaucoma leve que en el moderado-avanzado, ya que se ve artefactado por el efecto suelo. El OCT del complejo de células ganglionares de la mácula es la prueba que más casos clasifica de progresión y que tiene mayor acuerdo con el campo visual, independientemente de la severidad.ConclusiónEl estudio del complejo de células ganglionares de la mácula mediante OCT podría ser mejor biomarcador de progresión que el estudio de la capa de fibras del nervio óptico, en cualquier estadio de glaucoma. (AU)

Introduction: The aim of this work is to evaluate the usefulness of the study of the ganglion cell complex of the macula using optical coherence tomography (OCT) to estimate the progression of glaucoma according to its severity.Material and methodsThis is a retrospective cross-sectional study. It includes 205 eyes of 131 patients with glaucoma or ocular hypertension followed for a mean of 5.7years. The parameters and rates of three tests have been analyzed using the progression software of each instrument: visual field, OCT in the ganglion cell complex of the macula and in the nerve fiber layer of the optic nerve. The results of each test, the concordance between them and how they differ according to severity stage have been evaluated.ResultsVisual field classifies more cases of progression in moderate-advanced glaucoma, while in mild glaucoma its capacity is limited. Optic nerve fiber layer OCT classifies more cases of progression in mild glaucoma than in moderate-advanced glaucoma, as it is artifacted by the floor effect. OCT of the macular ganglion cell complex is the test that classifies more cases of progression and has the highest agreement with visual field, regardless of severity.ConclusionThe study of the macula ganglion cell complex using OCT could be a better biomarker of progression than the study of the optic nerve fiber layer, at any stage of glaucoma. (AU)

Lista de verificación: tomografía computarizada de cuello en urgencias no traumáticas / Checklist: Neck computed tomography in non-traumatic emergencies

A los pacientes que acuden a urgencias con síntomas inflamatorio/infecciosos a nivel cervical o con masas que pueden comprometer el tracto aerodigestivo o las estructuras vasculares, es necesario hacerles una tomografía computarizada (TC) de cuello con contraste. Su interpretación radiológica se ve dificultada por la complejidad anatómica y la interrelación fisiopatológica entre los diferentes sistemas que lo componen, en un área de estudio relativamente pequeña. Estudios recientes proponen realizar una evaluación sistemática de las estructuras cervicales, utilizando para ello un listado de verificación de 7 elementos, para identificar correctamente la patología, y detectar los hallazgos incidentales que pueden interferir en el manejo del paciente. El objetivo de este trabajo es revisar los hallazgos de la TC en la patología no traumática del cuello en urgencias siguiendo una lectura sistemática, tras la cual se pueda realizar un informe radiológico estructurado, completo y conciso.(AU)

Patients attending the emergency department (ED) with cervical inflammatory/infectious symptoms or presenting masses that may involve the aerodigestive tract or vascular structures require a contrast-enhanced computed tomography (CT) scan of the neck. Its radiological interpretation is hampered by the anatomical complexity and pathophysiological interrelationship between the different component systems in a relatively small area. Recent studies propose a systematic evaluation of the cervical structures, using a 7-item checklist, to correctly identify the pathology and detect incidental findings that may interfere with patient management. As a conclusion, the aim of this paper is to review CT findings in non-traumatic pathology of the neck in the ED, highlighting the importance of a systematic approach in its interpretation and synthesis of a structured, complete, and concise radiological report.(AU)

Electrical impedance tomography: Usefulness for respiratory physiotherapy in critical illnesses.

Respiratory physiotherapy, including the management of invasive mechanical ventilation (MV) and noninvasive mechanical ventilation (NIV), is a key supportive intervention for critically ill patients. MV has potential for inducing ventilator-induced lung injury (VILI) as well as long-term complications related to prolonged bed rest, such as post-intensive care syndrome and intensive care unit acquired weakness. Physical and respiratory therapy, developed by the critical care team, in a timely manner, has been shown to prevent these complications. In this pathway, real-time bedside monitoring of changes in pulmonary aeration and alveolar gas distribution associated with postural positioning, respiratory physiotherapy techniques and changes in MV strategies can be crucial in guiding these procedures, providing safe therapy and prevention of potential harm to the patient. Along this path, electrical impedance tomography (EIT) has emerged as a new key non-invasive bedside strategy free of radiation, to allow visualization of lung recruitment. This review article presents the main and potential applications of EIT in relation to physiotherapy techniques in the ICU setting.

Computational model based on optical coherence tomography (OCT) skin scanning to identify and quantify acute radiation dermatitis (ARD): a prospective diagnostic study.

BACKGROUND: acute radiation dermatitis (ARD) is the most widely reported radiotherapy-induced adverse event. Currently, there is no objective or reliable method to measure ARD. OBJECTIVE: our main objective was to identify and quantify the effects of radiotherapy with a computational model using optical coherence tomography (OCT) skin scanning. Secondary objectives included determining the ARD impact of different radiotherapeutic schemes and adjuvant topical therapies. METHODS: we conducted a prospective, single-center case series study in a tertiary referral center of patients with breast cancer who were eligible for whole breast radiotherapy (WBRT). RESULTS: a total of 39 women were included and distributed according to the radiotherapeutic schemes (15, 20, and 25 fractions). A computational model was designed to quantitatively analyze OCT findings. After radiotherapy, OCT scanning was more sensitive revealing vascularization changes in 84.6% of the patients (vs 69.2% of the patients with ARD by clinical examination). OCT quantified an increased vascularization at the end of WBRT (P < .05) and a decrease after 3 months (P = .032). Erythematous skin changes by OCT were more pronounced in the 25-fraction regime. CONCLUSION: an OCT computational model allowed for the identification and quantification of vascularization changes on irradiated skin, even in the absence of clinical ARD. This may allow the design of standardized protocols for ARD beyond the skin color of the patients involved.

Review of electrical impedance tomography in the pediatric patient.

Electrical impedance tomography (EIT) is a new method of monitoring non-invasive mechanical ventilation, at the bedside and useful in critically ill patients. It allows lung monitoring of ventilation and perfusion, obtaining images that provide information on lung function. It is based on the physical principle of impedanciometry or the body's ability to conduct an electrical current. Various studies have shown its usefulness both in adults and in pediatrics in respiratory distress syndrome, pneumonia and atelectasis in addition to pulmonary thromboembolism and pulmonary hypertension by also providing information on pulmonary perfusion, and may be very useful in perioperative medicine; especially in pediatrics avoiding repetitive imaging tests with ionizing radiation.

Dislodgment of continuous suprascapular nerve block catheters after physiotherapy: A cadaver study.

BACKGROUND: Continuous peripheral nerve blocks are commonly used for pain management. However, the incidence of catheter dislodgement or migration is unclear, and may be underestimated and underreported. Our objective was to assess suprascapular catheter tip positioning before and after routine simulated shoulder physiotherapy manipulation in an anatomical cadaver model. METHOD: Eight ultrasound-guided continuous suprascapular nerve block catheters were placed in cryopreserved fresh cadavers. Computed tomography (CT) confirmed the location of the catheter tip after injection of 1 ml of contrast medium. We performed a series of standardized shoulder movements during a simulated shoulder physiotherapy session in cadavers. Following this, we administered 1 ml of methylene blue through the catheters, and then performed anatomical dissections to accurately identify the location of the catheter tips and compare them to their placement prior to the 'physiotherapy'. RESULT: CT imaging confirmed the location of the catheter tips at the suprascapular notch in all cases. However, following physiotherapy, 2 catheters (25%) were found to have migrated - specifically, 1 was located in the supraspinatus muscle, and the other was located in the trapezius muscle. CONCLUSION: Our findings suggest that catheter dislodgement may occur in approximately 25% of cases following simulated physiotherapy manipulation. However, further research is needed to determine the read incidence of catheter dislodgement in clinical practice.

¿Cómo calcular el volumen litiásico y cuál es su aplicación quirúrgica? / How to estimate stone volume and its use in stone surgery: A comprehensive review?

Objetivo Las guías actuales para el tratamiento intervencionista sugieren el diámetro acumulativo de la litiasis (DAL) como factor decisivo en la elección del tratamiento quirúrgico óptimo (ureteroscopia [URS], litotricia extracorpórea por ondas de choque [LEOCh] y nefrolitotomía percutánea [NLPC]). El volumen litiásico (VL) se ha introducido recientemente para obtener una estimación más precisa de la carga litiásica. El objetivo de esta revisión es resumir los métodos disponibles para calcular el VL y su aplicación quirúrgica. Material y métodos En diciembre de 2022 se realizó una revisión sistemática de la literatura mediante búsquedas en las bases de datos Embase, Cochrane y Pubmed. Los artículos se consideraron elegibles si describían la medición del VL o la tasa libre de litiasis (TLL) tras diferentes modalidades de tratamiento (LEOCh, URS, NLPC) o la expulsión espontánea, basándose en la medición del VL. Dos revisores evaluaron de forma independiente la elegibilidad y la calidad de los artículos y realizaron la extracción de datos. Resultados En total se incluyeron 28 estudios. Todos los estudios utilizaron diferentes técnicas para calcular el VL. La medición automática del volumen pareció ser más precisa que la estimación del volumen. Los estudios in vitro mostraron que la medición automática del volumen se ajustaba más al volumen real de la litiasis, con una menor variabilidad interobservador. A diferencia de la NLPC y la LEOCh, en la URS se observó que el VL era un mejor predictor de mejor la TLL que el diámetro litiásico mayor o el diámetro acumulativo en litiasis >20mm. Conclusiones Calcular el VL —de forma manual o automática— es factible, y probablemente se ajuste más a la carga litiásica real. Aunque en el caso de las litiasis grandes tratadas mediante cirugía intrarrenal retrógrada el VL parece predecir mejor la TLL, la superioridad del VL en todas las cargas litiásicas y para todos los tipos de tratamiento está aún por demostrar. ... (AU)

Objective Current interventional guidelines refer to the cumulative stone diameter to choose the appropriate surgical modality (ureteroscopy (URS), extracorporeal shockwave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL)). The stone volume (SV) has been introduced recently, to better estimate the stone burden. This review aimed to summarize the available methods to evaluate the SV and its use in urolithiasis treatment. Material and methods A comprehensive review of the literature was performed in December 2022 by searching Embase, Cochrane and Pubmed databases. Articles were considered eligible if they described SV measurement or the stone free rate after different treatment modalities (SWL, URS, PCNL) or spontaneous passage, based on SV measurement. Two reviewers independently assessed the eligibility and the quality of the articles and performed the data extraction. Results In total, 28 studies were included. All studies used different measurement techniques for stone volume. The automated volume measurement appeared to be more precise than the calculated volume. In vitro studies showed that the automated volume measurement was closer to actual stone volume, with a lower inter-observer variability. Regarding URS, stone volume was found to be more predictive of stone free rates as compared to maximum stone diameter or cumulative diameter for stones >20mm. This was not the case for PCNL and SWL. Conclusions Stone volume estimation is feasible, manually or automatically and is likely a better representation of the actual stone burden. While for larger stones treated by retrograde intrarenal surgery, stone volume appears to be a better predictor of SFR, the superiority of stone volume throughout all stone burdens and for all stone treatments, remains to be proven. Automated volume acquisition is more precise and reproducible than calculated volume. (AU)

Desenmascarando la polimialgia reumática, papel de la Medicina Nuclear / Decoding polymyalgia rheumatica, the role of Nuclear Medicine Imaging

La polimialgia reumática (PMR) es una enfermedad inflamatoria de las articulaciones que se presenta en pacientes mayores de 50 años con dolor y rigidez matutina prolongada en las cinturas del hombro y la cadera y en el cuello. La falta de hallazgos clínicos específicos, signos de laboratorio, biomarcadores y métodos de imagen establecidos dificulta el diagnóstico de los pacientes con esta enfermedad. La 18F-FDG PET/TC es una técnica de imagen funcional que constituye una herramienta consolidada en Oncología y que también ha demostrado su utilidad en el campo de las enfermedades inflamatorias. El objetivo de este trabajo es presentar evidencia bibliográfica sobre el uso de métodos de imagen molecular como la PET/TC para el diagnóstico precoz, la evaluación de la actividad de la enfermedad y la respuesta terapéutica en la PMR. Al mismo tiempo, se consideran las ventajas, las desventajas y las contraindicaciones de otros métodos (AU)

Polymyalgia rheumatica (PMR) is an inflammatory joint disease that presents in patients older than 50 years with prolonged morning pain and stiffness in the shoulder and hip joints and neck. The lack of specific clinical findings, laboratory signs, biomarkers and established imaging methods makes it difficult to diagnose patients with this disease. 18F-FDG PET/CT is a functional imaging technique that is an established tool in oncology and has also proven useful in the field of inflammatory diseases. The aim of this paper is to present literature evidence on the use of molecular imaging methods such as PET/CT for early diagnosis, assessment of disease activity and therapeutic response in PMR. At the same time, the advantages, disadvantages and contraindications of other methods are considered (AU)

Implantación de un protocolo de angio-TC coronaria basado en el índice de masa corporal: reducción de dosis, calidad de imagen y rendimiento diagnóstico / Implementing a coronary CT angiography protocol based on the body mass index: radiation dose reduction, image quality, and diagnostic performance

Objetivos: Valorar la relación entre el score de calcio coronario y la elección posterior del kilovoltaje según el criterio del radiólogo en un protocolo estándar (PE) de angio-TC coronaria (aTCC) para descartar enfermedad coronaria. Cuantificar la reducción de la radiación ionizante después de vincular el kilovoltaje al índice de masa corporal en un protocolo de baja dosis (PBD) con reconstrucción iterativa de modelado. Valorar la calidad de imagen y el rendimiento diagnóstico del PBD. Material y método: Las características antropométricas, el score de calcio, los niveles de kilovoltaje y los valores de dosis estimada específica para el tamaño (SSDE) y del producto dosis-longitud fueron comparados entre un grupo de 50 pacientes con PBD reclutados prospectivamente y una cohorte histórica adquirida con el PE. Estos parámetros, el número de segmentos coronarios no valorables sin y con tolerancia de fase, la atenuación y la relación señal-ruido en la aorta ascendente en el PBD fueron correlacionados con una calidad de imagen de nivel excelente según una escala semicuantitativa. El rendimiento diagnóstico por paciente fue calculado usando la revaloración clínica a los 24 meses como el método diagnóstico de referencia, incluyendo las pruebas derivadas. Resultados: En el PE existía una relación entre la presencia de calcio coronario y la elección de kilovoltajes altos (p=0,02), que desaparecía en el PBD (p=0,47). Los valores de SSDE y de DLP en el PBD fueron significativamente inferiores y presentaron menor dispersión que en el PE (9,22 mGy [RIQ 7,84-12,1 mGy] y 97 mGy*cm [RIQ 78-134 mGy*cm] contra 26,5 mGy [RIQ 21,3-36,3 mGy] y 253 mGy*cm [RIQ 216-404 mGy*cm]; p <0,001 para las comparaciones de las medianas y de las dispersiones entre ambos grupos)...(AU)

Objectives: To evaluate the relation between the coronary calcium score and the posterior choice of kilovoltage according to radiologists’ criteria in a standard coronary CT angiography protocol to rule out coronary disease. To quantify the reduction in ionizing radiation after linking kilovoltage to patients’ body mass index in a low-dose protocol with iterative model reconstruction. To evaluate the image quality and diagnostic performance of the low-dose protocol. Material and methods: We compared anthropometric characteristics, calcium score, kilovoltage levels, size-specific dose estimates (SSDE), and the dose-length product (DLP) between a group of 50 patients who were prospectively recruited to undergo coronary CT angiography with a low-dose protocol and a historical group of 50 patients who underwent coronary CT angiography with the standard protocol. We correlated these parameters, the number of coronary segments that could not be evaluated with and without temporal padding, the attenuation, and the signal-to-noise ratio in the ascending aorta in the low-dose protocol with excellent imaging quality according to a semiquantitative scale. To calculate the diagnostic performance per patient, we used 24-month clinical follow-up including all tests as the gold standard. Results: In the standard protocol, the presence of coronary calcium correlated with the selection of high kilovoltage (P=0.02); this correlation was not found in the low-dose protocol (P=0.47). Median values of SSDE and DLP were significantly (P<0.001) lower and less dispersed in the low-dose protocol [9.22 mGy (IQR 7.84-12.1 mGy) vs. 26.5 mGy (IQR 21.3-36.3 mGy) in the standard protocol] and [97mGy*cm (IQR 78-134mGy*cm) vs. 253mGy*cm (IQR 216-404mGy*cm) in the standard protocol], respectively...(AU)

Prótesis mitral mecánica disfuncionante: cuando el trombo sobre pannus dificulta el diagnóstico / Dysfunctioning mechanical mitral valve prosthesis: When thrombus over pannus makes hinders diagnosis

La obstrucción de una válvula protésica es una complicación rara pero que puede ser letal. Las causas más frecuentes son la formación de trombos y pannus, en ausencia de datos infecciosos. El diagnóstico no siempre es sencillo recurriendo a la realización de tomografía computarizada (TC) cardiaca, y en el 46-85% de los casos coexisten trombo y pannus, por lo que el diagnóstico se complica. Un diagnóstico rápido es esencial para evitar un desenlace fatal de esta patología, cuya mortalidad, a pesar de un tratamiento correcto, es elevada.(AU)

Prosthetic valve obstruction is a rare but potentially lethal complication. The most frequent causes are thrombus and pannus formation, in the absence of infectious data. Diagnosis is not always easy using cardiac CT scanning and in 46-85% of cases thrombus and pannus coexist, complicating the diagnosis. A rapid diagnosis is essential to avoid a fatal outcome of this pathology whose mortality, despite correct treatment, is high.(AU)

Microcomputed-Tomographic Analysis of the Root Canal Morphology of the Mandibular First Molars in a Malaysian Subpopulation Using Two Classification Systems / Análisis por Tomografía Microcomputada de la Morfología del Conducto Radicular de los Primeros Molares Mandibulares en una Subpoblación de Malasia Utilizando dos Sistemas de Clasificación

SUMMARY: This work investigated the morphology of the root canal system of the mandibular first molar in a Malaysian subpopulation. Using micro-computed tomography with an isotropic resolution of 22 µm, 140 mandibular first molars were scanned. MIMICS software was used for segmentation, 3-D reconstruction and analysis of the acquired images. The canal configuration was described using Vertucci [supported by the supplementary configurations proposed by Sert & Bayirli (2004)] and Ahmed et al. (2027), coding systems. The chi-square test was used to assess the association between qualitative variables. By non-considering intercanal communications, Vertucci types IV (17.1%) and I (76.4%) were the most frequently reported configurations in the mesial and distal roots, respectively. Of the reported configurations, 24.3% and 4.3% were non-classifiable by Vertucci system in the mesial and distal roots, respectively. Up to 63.6% and 9.3% of the reported configurations were non- classifiable, and type I was the most frequent when considering intercanal communications (7.1% and 76.4% in the mesial and distal roots, respectively). According to Ahmed et al., system, almost half of the sample had more than four digits (47.9%), followed by the 3-digits category (20.71%). In both systems, a significant association was found between the canal configuration and the root type (p<0.001). The mandibular first molar of this Malaysian subpopulation demonstrated a wide range of root canal morphology. When compared to the Vertucci system, the system developed by Ahmed et al., successfully classified all molars configurations despite their level of complexity. The complex canal anatomy of mandibular first molars in this subpopulation warrants special attention during root canal treatment procedures.

En este trabajo se investigó la morfología del sistema de conductos radiculares del primer molar mandibular en una subpoblación de Malasia. Utilizando tomografía microcomputada con una resolución isotrópica de 22 µm, se escanearon 140 primeros molares mandibulares. Se utilizó el software MIMICS para segmentar (enmascarar), reconstruir en 3D, visualizar y analizar las imágenes adquiridas. La configuración del canal se describió utilizando Vertucci respaldado por las configuraciones complementarias propuestas por Sert & Bayirli (2004)] y Ahmed et al. (2017, 2020), sistemas de codificación. Se utilizó la prueba de chi-cuadrado para evaluar la asociación entre variables cualitativas. Sin considerar las comunicaciones intercanales, los tipos Vertucci IV (17,1%) y I (76,4%) fueron las configuraciones reportadas con mayor frecuencia en las raíces mesiales y distales, respectivamente. De las configuraciones reportadas, el 24,3 % y el 4,3 % fueron no clasificables por el sistema de Vertucci en las raíces mesial y distal, respectivamente. Hasta el 63,6 % y el 9,3 % de las configuraciones reportadas fueron no clasificables, siendo la tipo I la más frecuente al considerar las comunicaciones intercanales (7,1 % y 76,4 % en las raíces mesiales y distales, respectivamente). Según Ahmed et al. (2017, 2020) en el sistema, casi la mitad de la muestra tenía más de cuatro dígitos (47,9 %), seguido por la categoría de 3 dígitos (20,71 %). En ambos sistemas se encontró una asociación significativa entre la configuración del canal y el tipo de raíz (p<0,001). El primer molar mandibular de esta subpoblación de Malasia demostró una amplia gama morfológica del conducto radicular. En comparación con el sistema Vertucci, el sistema desarrollado por Ahmed et al. (2017, 2020) clasificaron con éxito todas las configuraciones de los molares a pesar de su nivel de complejidad. La compleja anatomía del canal de los primeros molares mandibulares en esta subpoblación merece una atención especial durante los procedimientos de tratamiento de conducto.

Implementing a coronary CT angiography protocol based on the body mass index: Radiation dose reduction, image quality, and diagnostic performance.

OBJECTIVES: To evaluate the relation between the coronary calcium score and the posterior choice of kilovoltage according to radiologists' criteria in a standard coronary CT angiography protocol to rule out coronary disease. To quantify the reduction in ionizing radiation after linking kilovoltage to patients' body mass index in a low-dose protocol with iterative model reconstruction. To evaluate the image quality and diagnostic performance of the low-dose protocol. MATERIAL AND METHODS: We compared anthropometric characteristics, calcium score, kilovoltage levels, size-specific dose estimates (SSDE), and the dose-length product (DLP) between a group of 50 patients who were prospectively recruited to undergo coronary CT angiography with a low-dose protocol and a historical group of 50 patients who underwent coronary CT angiography with the standard protocol. We correlated these parameters, the number of coronary segments that could not be evaluated with and without temporal padding, the attenuation, and the signal-to-noise ratio in the ascending aorta in the low-dose protocol with excellent imaging quality according to a semiquantitative scale. To calculate the diagnostic performance per patient, we used 24-month clinical follow-up including all tests as the gold standard. RESULTS: In the standard protocol, the presence of coronary calcium correlated with the selection of high kilovoltage (p = 0.02); this correlation was not found in the low-dose protocol (p = 0.47). Median values of SSDE and DLP were significantly (p < 0.001) lower and less dispersed in the low-dose protocol [9.22 mGy (IQR 7.84-12.1 mGy) vs. 26.5 mGy (IQR 21.3-36.3 mGy) in the standard protocol] and [97 mGy cm (IQR 78-134 mGy cm) vs. 253 mGy cm (IQR 216-404 mGy cm) in the standard protocol], respectively. The overall quality of the images obtained with the low-dose protocol was considered good or excellent in 96% of the studies. The parameters associated with image quality in a multivariable model (C statistic = 0.792) were heart rate (estimated coefficient, -0,12 [95% confidence interval: -0.2, -0.04]; p < 0.01) and the SSDE (estimated coefficient, -0,26 [95% confidence interval: -0.51, -0.01]; p < 0.05). The CAD-RADS modifier for a not fully evaluable or diagnostic study was used on two occasions (4%); the final measures for the diagnosis of coronary disease were sensitivity 100%, specificity 94%, and efficacy 94%. CONCLUSIONS: In the standard protocol, the radiologist selects higher kilovoltage for CT angiography studies for patients whose previous calcium score indicates the presence of coronary calcium. In the low-dose protocol, linking kilovoltage with body mass index enables the dose of radiation to be reduced by 65% while obtaining excellent or good image quality in 96% of studies and excellent diagnostic performance.