title: Time-domain analysis of scrotal thermoregulatory impairment in varicocele.
abstract: Varicocele is a common male disease defined as the pathological dilatation of the pampiniform plexus and scrotal veins with venous blood reflux. Varicocele usually impairs the scrotal thermoregulation via a hemodynamic alteration, thus inducing an increase in cutaneous temperature. The investigation of altered scrotal thermoregulation by means of thermal infrared imaging has been proved to be useful in the study of the functional thermal impairment. In this study, we use the Control System Theory to analyze the time-domain dynamics of the scrotal thermoregulation in response to a mild cold challenge. Four standard time-domain dynamic parameters of a prototype second order control system (Delay Time, Rise Time, closed poles locations, steady state error) and the static basal temperatures were directly estimated from thermal recovery curves. Thermal infrared imaging data from 31 healthy controls (HCS) and 95 varicocele patients were processed. True-positive predictions, by comparison with standard echo color Doppler findings, higher than 87% were achieved into the proper classification of the disease stage. The proposed approach could help to understand at which specific level the presence of the disease impacts the scrotal thermoregulation, which is also involved into normal spermatogenesis process.
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti Pescara Chieti-Pescara, Italy ; Institute for Advanced Biomedical Technologies (ITAB), G. d'Annunzio University Chieti-Pescara, Italy.
authors.forename: Enas
authors.initials: E
authors.lastname: Ismail
authors.affiliation: DIIGA, Polytechnic University of Marche Ancona, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Orlando
authors.affiliation: Department of Urology, Ospedale Civile Pescara, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Pompa
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti Pescara Chieti-Pescara, Italy ; Institute for Advanced Biomedical Technologies (ITAB), G. d'Annunzio University Chieti-Pescara, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Gabrielli
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti Pescara Chieti-Pescara, Italy ; Institute for Advanced Biomedical Technologies (ITAB), G. d'Annunzio University Chieti-Pescara, Italy.
authors.forename: Luigino
authors.initials: L
authors.lastname: Di Donato
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti Pescara Chieti-Pescara, Italy ; Institute for Advanced Biomedical Technologies (ITAB), G. d'Annunzio University Chieti-Pescara, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Cardone
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti Pescara Chieti-Pescara, Italy ; Institute for Advanced Biomedical Technologies (ITAB), G. d'Annunzio University Chieti-Pescara, Italy.
authors.forename: Arcangelo
authors.initials: A
authors.lastname: Merla
keywords: Functional Infrared (fIR); control system; modeling; multinomial logistic regression; scrotal temperature; scrotal thermoregulation; varicocele