1 Diagnostic and Interventional Ultrasound Unit, Valle del Serchio General Hospital, Lucca, Italy.
2 Pulmonary Medicine Unit, Department of Cardiovascular and Thoracic Sciences, Scientifico, Rome, Italy.
3 Department of Woman and Child Health and Public Health, Scientifico, Rome, Italy.
4 Fondazione Policlinico Universitario Agostino Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico, Rome, Italy.
5 Emergency Department, Fondazione Policlinico San Matteo, Istituto di Ricovero e Cura a Carattere Scientifico, and Department of Internal Medicine and Therapeutics, University of Pavia, Pavia, Italy.