Caracterización metabólica de los cambios pulmonares estructurales en pacientes con hallazgos incidentales sugestivos de neumonía por COVID-19 en estudios 18F-FDG PET/CT. Perspectivas fisiopatológicas de imágenes multimodales obtenidas durante la pandemia / Metabolic characterization of structural lung changes in patients with findings suggestive of incidental COVID-19 pneumonia on 18F-FDG PET/CT: Pathophysiological insights from multimodal images obtained during the pandemic

Objetivo Evaluar la captación metabólica de diferentes signos tomográficos observados en pacientes con hallazgos estructurales incidentales sugestivos de neumonía por COVID-19 mediante PET/TC con 18F-FDG. Material y métodos Se analizaron retrospectivamente 596 estudios PET/TC realizados desde el 21 de febrero de 2020 hasta el 17 de abril de 2020. Tras excluir 37 exploraciones (trazadores PET diferentes a la 18F-FDG y estudios cerebrales), se evaluó la actividad metabólica de varios cambios estructurales integrados en la puntuación CO-RADS mediante el SUVmáx de estudios multimodales con 18F-FDG. Resultados Se incluyeron 43 pacientes r COVID-19 en la 18F-FDG PET/TC (edad media: 68±12,3 años, 22 varones). Los valores de SUVmáx fueron mayores en los pacientes con categorías CO-RADS 5-6 respecto a los de categorías CO-RADS inferiores (6,1±3,0 vs. 3,6±2,1, p=0,004). En los pacientes con CO-RADS 5-6, las opacidades en vidrio deslustrado, la bilateralidad y las consolidaciones mostraron valores de SUVmáx más elevados (valores de la p de 0,01, 0,02 y 0,01, respectivamente). La distribución parcheada y el patrón crazy paving también se asociaron a valores de SUVmáx más elevados (valores de p de 0,002 y 0,01). Tras el análisis multivariable, el SUVmáx se asoció significativamente con un diagnóstico estructural positivo de neumonía por COVID-19 (odds ratio=0,63, intervalo de confianza del 95%=0,41-0,90; p=0,02). La curva ROC del modelo de regresión destinado a confirmar o descartar el diagnóstico estructural de neumonía por COVID-19 mostró un AUC de 0,77 (error estándar=0,072; p=0,003). Conclusiones En aquellos pacientes remitidos a 18F-FDG PET/TC por indicaciones oncológicas y no oncológicas estándar (43/559; 7,7%) durante la pandemia, la obtención de imágenes multimodales es una herramienta útil durante la detección incidental de neumonía (AU)

Purpose To evaluate the metabolic uptake of different tomographic signs observed in patients with incidental structural findings suggestive of COVID-19 pneumonia through 18F-FDG PET/CT. Material and methods We retrospectively analyzed 596 PET/CT studies performed from February 21, 2020 to April 17, 2020. After excluding 37 scans (non-18F-FDG PET tracers and brain studies), we analyzed the metabolic activity of several structural changes integrated in the CO-RADS score using the SUVmax of multimodal studies with 18F-FDG. Results Forty-three patients with 18F-FDG PET/CT findings suggestive of COVID-19 pneumonia were included (mean age: 68±12.3 years, 22 male). SUVmax values were higher in patients with CO-RADS categories 5–6 than in those with lower CO-RADS categories (6.1±3.0 vs. 3.6±2.1, p=0.004). In patients with CO-RADS 5–6, ground-glass opacities, bilaterality and consolidations exhibited higher SUVmax values (p-values of 0.01, 0.02 and 0.01, respectively). Patchy distribution and crazy paving pattern were also associated with higher SUVmax (p-values of 0.002 and 0.01). After multivariate analysis, SUVmax was significantly associated with a positive structural diagnosis of COVID-19 pneumonia (odds ratio=0.63, 95% confidence interval=0.41–0.90; p=0.02). The ROC curve of the regression model intended to confirm or rule out the structural diagnosis of COVID-19 pneumonia showed an AUC of 0.77 (standard error=0.072, p=0.003). Conclusions In those patients referred for standard oncologic and non-oncologic indications (43/559; 7.7%) during pandemic, imaging with 18F-FDG PET/CT is a useful tool during incidental detection of COVID-19 pneumonia. Several CT findings characteristic of COVID-19 pneumonia, specifically those included in diagnostic CO-RADS scores (5–6), were associated with higher SUVmax values (AU)

Metabolic characterization of structural lung changes in patients with findings suggestive of incidental COVID-19 pneumonia on 18F-FDG PET/CT. Pathophysiological insights from multimodal images obtained during the pandemic.

PURPOSE: To evaluate the metabolic uptake of different tomographic signs observed in patients with incidental structural findings suggestive of COVID-19 pneumonia through 18F-FDG PET/CT. MATERIALS AND METHODS: We retrospectively analyzed 596 PET/CT studies performed from February 21, 2020 to April 17, 2020. After excluding 37 scans (non-18F-FDG PET tracers and brain studies), we analyzed the metabolic activity of several structural changes integrated in the CO-RADS score using the SUVmax of multimodal studies with 18F-FDG. RESULTS: Forty-three patients with 18F-FDG PET/CT findings suggestive of COVID-19 pneumonia were included (mean age: 68±12.3 years, 22 male). SUVmax values were higher in patients with CO-RADS categories 5-6 than in those with lower CO-RADS categories (6.1±3.0 vs. 3.6±2.1, p=0.004). In patients with CO-RADS 5-6, ground-glass opacities, bilaterality and consolidations exhibited higher SUVmax values (p-values of 0.01, 0.02 and 0.01, respectively). Patchy distribution and crazy paving pattern were also associated with higher SUVmax (p-values of 0.002 and 0.01). After multivariate analysis, SUVmax was significantly associated with a positive structural diagnosis of COVID-19 pneumonia (odds ratio=0.63, 95% confidence interval=0.41-0.90; p=0.02). The ROC curve of the regression model intended to confirm or rule out the structural diagnosis of COVID-19 pneumonia showed an AUC of 0.77 (standard error=0.072, p=0.003). CONCLUSIONS: In those patients referred for standard oncologic and non-oncologic indications (43/559; 7.7%) during pandemic, imaging with 18F-FDG PET/CT is a useful tool during incidental detection of COVID-19 pneumonia. Several CT findings characteristic of COVID-19 pneumonia, specifically those included in diagnostic CO-RADS scores (5-6), were associated with higher SUVmax values.

Marcadas alteraciones en la morfología de la onda T asociadas a la isquemia inducida por dipiridamol / Pronounced alterations in T-wave morphology during dipyridamole-induced ischaemia

Describimos el caso de una mujer de 77 años portadora de enfermedad coronaria multivaso que exhibe marcados cambios en la morfología de la onda T durante la infusión de dipiridamol, un hallazgo inusual cuya exactitud diagnóstica es incierta en este contexto clínico. Las imágenes de SPECT gatillado (SPECT sincronizado con el ECG, Gated SPECT) evidenciaron la presencia de isquemia severa en regiones inferoposterior y posterolateral del ventrículo izquierdo con comportamiento normal de la motilidad y la función contráctil en respuesta al estrés vasodilatador. A propósito del caso se discuten los posibles mecanismos subyacentes y las implicaciones clínicas de los cambios electrocardiográficos observados. Las modificaciones del bucle-T durante la SPECT sensibilizada con vasodilatadores y su correlación con la magnitud (quantum) de miocardio isquémico merecen ser evaluadas (AU)

The case describes a 77-year-old woman with multivessel coronary disease exhibiting marked changes of T-wave morphology induced by dipyridamole, an unusual finding in which the diagnostic accuracy in this clinical context is uncertain. Gated-SPECT imaging demonstrated severe ischaemia extending through inferior and posterolateral regions of the left ventricle with normal motility and contractile function in response to vasodilator stress. Possible underlying mechanisms and clinical implications of observed electrocardiographic changes are discussed. T-loop modifications during vasodilator stress SPECT and correlation of these changes with the amount of ischaemic injury need further evaluation (AU)

Pronounced alterations in T-wave morphology during dipyridamole-induced ischaemia.

The case describes a 77-year-old woman with multivessel coronary disease exhibiting marked changes of T-wave morphology induced by dipyridamole, an unusual finding in which the diagnostic accuracy in this clinical context is uncertain. Gated-SPECT imaging demonstrated severe ischaemia extending through inferior and posterolateral regions of the left ventricle with normal motility and contractile function in response to vasodilator stress. Possible underlying mechanisms and clinical implications of observed electrocardiographic changes are discussed. T-loop modifications during vasodilator stress SPECT and correlation of these changes with the amount of ischaemic injury need further evaluation.