title: Difference method for analysing infrared images in pigs with elevated body temperatures.
abstract: Infrared imaging proves to be a quick and simple method for measuring temperature distribution on the pig's head. The study showed that infrared imaging and analysis with a difference ROI (region of interest) method may be used for early detection of elevated body temperature in pigs (> 39.5°C). A high specificity of approx. 85% and a high sensitivity of 86% existed. The only prerequisite is that there are at least 2 anatomical regions which can be recognised as reproducible in the IR image. Noise suppression is guaranteed by averaging the temperature value within both of these ROI. The subsequent difference imaging extensively reduces the off-set error which varies in every thermal IR-image.
authors.affiliation: Institute of General Radiology and Medical Physics, University of Veterinary Medicine, Hannover, Germany. Electronic address: carsten.siewert@tiho-hannover.de.
authors.forename: Carsten
authors.initials: C
authors.lastname: Siewert
authors.affiliation: Institute for Animal Nutrition, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Braunschweig, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Dänicke
authors.affiliation: Institute for Animal Nutrition, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Braunschweig, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Kersten
authors.affiliation: Institute for Animal Nutrition, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Braunschweig, Germany.
authors.forename: Bianca
authors.initials: B
authors.lastname: Brosig
authors.affiliation: Institute for Animal Nutrition, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Braunschweig, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Rohweder
authors.affiliation: Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine, Hannover, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Beyerbach
authors.affiliation: Institute of General Radiology and Medical Physics, University of Veterinary Medicine, Hannover, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Seifert
mesh_terms: D000465:Algorithms; D000818:Animals; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005334:Fever / Q000175:diagnosis* / Q000503:physiopathology*; D007259:Infrared Rays; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012881:Skin Temperature; D013552:Swine; D013817:Thermography / Q000295:instrumentation* / Q000379:methods*
keywords: Differenzverfahren; Driftfehler; Medical infrared imaging; Medizinische Infrarotbildgebung; Rauschen; Temperaturverteilung; difference method; drift error; image noise; induced fever; induziertes Fieber; temperature distribution