Low-dose chest CT for preoperative screening for SARS-CoV-2 infection TC torácica de baja dosis de radiación como técnica de cribado preoperatorio de infección por SARS-CoV-2

Introduction This study aimed to evaluate the role of chest computed tomography (CT) in complementing reverse transcription polymerase chain reaction (RT-PCR) in asymptomatic candidates for elective surgery in the context of the COVID-19 pandemic. Material and methods We prospectively included 464 asymptomatic patients who underwent a triple screening workup for SARS-CoV-2 infection (health questionnaire, RT-PCR, and low-dose chest CT) during the 48 hours prior to undergoing elective surgery. A positive RT-PCR and/or CT findings suggestive of COVID-19 (CO-RADS 4 / 5) were considered diagnostic criteria for SARS-CoV-2 infection. Results Most patients (64.7%) underwent otorhinolaryngology surgery. No patients had positive RT-PCR results or symptoms suggestive of SARS-CoV-2 in the health questionnaire. Only 22 (4.7%) had signs compatible with lung infection;in 20 of these, the CT findings were atypical or indeterminate for COVID-19 (CO-RADS 2 / 3) and in 2 they were compatible with COVID-19 pneumonia in resolution. In the immediate postoperative period, no cases of SARS-CoV-2 infection were confirmed. Conclusion In our series of asymptomatic patients, low-dose CT did not add any value to the results of RT-PCR and a health questionnaire in preoperative screening for SARS-CoV-2.

Low-dose chest CT for preoperative screening for SARS-CoV-2 infection.

INTRODUCTION: This study aimed to evaluate the role of chest computed tomography (CT) in complementing reverse transcription polymerase chain reaction (RT-PCR) in asymptomatic candidates for elective surgery in the context of the COVID-19 pandemic. MATERIAL AND METHODS: We prospectively included 464 asymptomatic patients who underwent a triple screening workup for SARS-CoV-2 infection (health questionnaire, RT-PCR, and low-dose chest CT) during the 48 h prior to undergoing elective surgery. A positive RT-PCR and/or CT findings suggestive of COVID-19 (CO-RADS 4/5) were considered diagnostic criteria for SARS-CoV-2 infection. RESULTS: Most patients (64.7%) underwent otorhinolaryngology surgery. No patients had positive RT-PCR results or symptoms suggestive of SARS-CoV-2 in the health questionnaire. Only 22 (4.7%) had signs compatible with lung infection; in 20 of these, the CT findings were atypical or indeterminate for COVID-19 (CO-RADS 2/3) and in 2 they were compatible with COVID-19 pneumonia in resolution. In the immediate postoperative period, no cases of SARS-CoV-2 infection were confirmed. CONCLUSION: In our series of asymptomatic patients, low-dose CT did not add any value to the results of RT-PCR and a health questionnaire in preoperative screening for SARS-CoV-2.

[Low-dose chest CT for preoperative screening for SARS-CoV-2 infection]. / TC torácica de baja dosis de radiación como técnica de cribado preoperatorio de infección por SARS-CoV-2.

Introduction: This study aimed to evaluate the role of chest computed tomography (CT) in complementing reverse transcription polymerase chain reaction (RT-PCR) in asymptomatic candidates for elective surgery in the context of the COVID-19 pandemic. Material and methods: We prospectively included 464 asymptomatic patients who underwent a triple screening workup for SARS-CoV-2 infection (health questionnaire, RT-PCR, and low-dose chest CT) during the 48 hours prior to undergoing elective surgery. A positive RT-PCR and/or CT findings suggestive of COVID-19 (CO-RADS 4 / 5) were considered diagnostic criteria for SARS-CoV-2 infection. Results: Most patients (64.7%) underwent otorhinolaryngology surgery. No patients had positive RT-PCR results or symptoms suggestive of SARS-CoV-2 in the health questionnaire. Only 22 (4.7%) had signs compatible with lung infection; in 20 of these, the CT findings were atypical or indeterminate for COVID-19 (CO-RADS 2 / 3) and in 2 they were compatible with COVID-19 pneumonia in resolution. In the immediate postoperative period, no cases of SARS-CoV-2 infection were confirmed. Conclusion: In our series of asymptomatic patients, low-dose CT did not add any value to the results of RT-PCR and a health questionnaire in preoperative screening for SARS-CoV-2.

TC torácica de baja dosis de radiación como técnica de cribado preoperatorio de infección por SARS-CoV-2 Low-dose chest CT for preoperative screening for SARS-CoV-2 infection

Introducción: El objetivo del presente estudio fue evaluar el papel de la tomografía computarizada (TC) de tórax complementaria a la prueba de la reacción en cadena de la polimerasa con transcripción inversa (RT-PCR) en pacientes asintomáticos candidatos a cirugía electiva en el contexto de la pandemia de COVID-19. Material y métodos: Se incluyeron, de forma prospectiva, 464 pacientes asintomáticos que se sometieron a una triple estrategia de cribado de infección por SARS-CoV-2 (cuestionario de salud, prueba de RT-PCR y TC torácica de baja dosis) durante las 48 horas previas a la realización de una cirugía electiva. Un resultado positivo en la prueba de RT-PCR y/o la identificación de hallazgos tomográficos sugestivos de neumonía COVID-19 (categorías CO-RADS 4 y 5) fueron considerados criterios diagnósticos de infección por SARS-CoV-2. Resultados: La mayor parte de los pacientes se sometieron a cirugías de otorrinolaringología (64,7%). Ningún paciente presentó un resultado positivo en la prueba de RT-PCR ni síntomas sugestivos de infección por SARS-CoV-2 en el cuestionario de salud. Únicamente 22 (4,7%) mostraron signos compatibles con infección pulmonar;20 de ellos atípica o indeterminada para COVID-19 (CO-RADS 2, 3) y 2 compatibles con neumonía COVID-19 en resolución. Durante el postoperatorio inmediato no se confirmó ningún caso positivo para SARS-CoV-2. Conclusión: En nuestra serie, la realización de una TC torácica de baja dosis de radiación en pacientes asintomáticos para el cribado preoperatorio de infección por SARS-CoV-2 no proporcionó un valor diagnóstico adicional a la RT-PCR y el cuestionario de salud.

Chest computed tomography findings in different phases of SARS-CoV-2 infection

Objective To compare the findings on chest computed tomography (CT) in patients with COVID-19 during different phases of the disease and to evaluate the reproducibility of a visual radiologic score for estimating the extent of lung involvement. Methods We retrospectively reviewed chest CT studies from 182 patients with RT-PCR findings positive for SARS-CoV-2. Patients were classified according to the time elapsed from the onset of symptoms, as follows: early (0-4 days), intermediate/progressive (5-9 days), or advanced (≥10 days). We analyzed the frequency of each radiologic finding, as well as the pattern, appearance, and predominant distribution of lung involvement. A visual tomographic score (range, 0-25) was used to estimate the extent of involvement in each lobe and in the total lung volume. Results The predominant CT finding was the ground-glass pattern (n = 110;60.4%), the most common distribution was peripheral (n = 116;66.7%), and the most prevalent appearance was typical (n = 112;61.5%). The halo sign was seen most frequently in the early phase (25%), whereas ground-glass opacities were more common in the intermediate/progressive and advanced phases. The median severity score was 10 (IQR: 5-13), and the scores increased as the disease progressed. The interobserver agreement (kappa) was 0.92 for the appearance, 0.84 for the distribution, 0.70 for the predominant pattern, and 0.89 for the visual score. Conclusion The CT findings in patients with COVID-19 vary with the course of the infection. The proposed visual radiologic score is a simple, reproducible, and reliable tool for assessing lung involvement in COVID-19 pneumonia. Resumen Objetivo Comparar los hallazgos radiológicos mediante tomografía computarizada (TC) torácica en pacientes con COVID-19 en diferentes fases de la enfermedad y evaluar la reproducibilidad de unscore radiológico visual para estimar la extensión de la afectación pulmonar. Métodos Se evaluaron retrospectivamente las tomografías computarizadas de tórax de 182 pacientes con RT-PCR positiva para SARS-CoV-2. En función del tiempo de evolución de la infección, los pacientes fueron clasificados en tres grupos/estadios: fase precoz (0-4 días), intermedia/progresiva (5-9 días) y avanzada (≥10 días). Se analizó la frecuencia de cada hallazgo radiológico, así como el patrón, la apariencia y la distribución predominantes de la afectación pulmonar. La extensión de la afectación pulmonar se estimó para cada lóbulo pulmonar y para el volumen pulmonar total mediante un score tomográfico visual (rango 0-25). Resultados El hallazgo tomográfico predominante fue el patrón en vidrio deslustrado (n = 110, 60,4%), la distribución más frecuente, la periférica (n = 116, 66,7%) y la apariencia más prevalente, la típica (n = 112, 61,5%). El “signo del halo” se encontró más frecuentemente en la fase precoz (25%), mientras que las opacidades en vidrio deslustrado, el patrón en empedrado y las líneas subpleurales fueron más frecuentes en las fases intermedia/progresiva y avanzada. La mediana delscore de gravedad fue de 10 (RIQ: 5-13), aumentando los valores con la progresión de la enfermedad. El acuerdo interobservador (kappa, k) para la apariencia, la distribución y el patrón predominante, así como para el score visual fueron de 0,92;0,84;0,70, y 0,89;respectivamente. Conclusión Los hallazgos tomográficos en la COVID-19 varían con el curso de la infección. Elscore radiológico sugerido es una herramienta sencilla, reproducible y fiable para evaluar la afectación pulmonar en la neumonía COVID-19.

Chest computed tomography findings in different phases of SARS-CoV-2 infection. / Hallazgos en la tomografía computarizada de tórax en las fases evolutivas de la infección por SARS-CoV-2.

OBJECTIVE: To compare the findings on chest computed tomography (CT) in patients with COVID-19 during different phases of the disease and to evaluate the reproducibility of a visual radiologic score for estimating the extent of lung involvement. METHODS: We retrospectively reviewed chest CT studies from 182 patients with RT-PCR findings positive for SARS-CoV-2. Patients were classified according to the time elapsed from the onset of symptoms, as follows: early (0-4 days), intermediate/progressive (5-9 days), or advanced (≥10 days). We analyzed the frequency of each radiologic finding, as well as the pattern, appearance, and predominant distribution of lung involvement. A visual tomographic score (range, 0-25) was used to estimate the extent of involvement in each lobe and in the total lung volume. RESULTS: The predominant CT finding was the ground-glass pattern (n=110; 60.4%), the most common distribution was peripheral (n = 116; 66.7%), and the most prevalent appearance was typical (n=112; 61.5%). The halo sign was seen most frequently in the early phase (25%), whereas ground-glass opacities were more common in the intermediate/progressive and advanced phases. The median severity score was 10 (IQR: 5-13), and the scores increased as the disease progressed. The interobserver agreement (kappa) was 0.92 for the appearance, 0.84 for the distribution, 0.70 for the predominant pattern, and 0.89 for the visual score. CONCLUSION: The CT findings in patients with COVID-19 vary with the course of the infection. The proposed visual radiologic score is a simple, reproducible, and reliable tool for assessing lung involvement in COVID-19 pneumonia.