title: First in vivo application of microwave radiometry in human carotids: a new noninvasive method for detection of local inflammatory activation.
abstract: OBJECTIVE
  This study investigated whether temperature differences: 1) can be measured in vivo noninvasively by microwave radiometry (MR); and 2) are associated with ultrasound and histological findings.
  
  
  BACKGROUND
  Studies of human carotid artery samples showed increased heat production. MR allows in vivo noninvasive measurement of internal temperature of tissues.
  
  
  METHODS
  Thirty-four patients undergoing carotid endarterectomy underwent screening of carotid atherosclerosis by ultrasound and MR. Healthy volunteers were enrolled as a control group. During ultrasound study, plaque texture, plaque surface, and plaque echogenicity were analyzed. Temperature difference (ΔT) was assigned as maximal minus minimum temperature. Association of thermographic with ultrasound and histological findings was performed.
  
  
  RESULTS
  ΔT was higher in atherosclerotic carotid arteries compared with the carotid arteries of controls (p < 0.01). Fatty plaques had higher ΔT compared with mixed and calcified (p < 0.01) plaques. Plaques with ulcerated surface had higher ΔT compared with plaques with irregular and regular surface (p < 0.01). Heterogeneous plaques had higher ΔT compared with homogenous (p < 0.01). Specimens with thin fibrous cap and intense expression of CD3, CD68, and vascular endothelial growth factor (VEGF) had higher ΔT compared with specimens with thick cap and low expression of CD3, CD68, and VEGF (p < 0.01).
  
  
  CONCLUSIONS
  MR provides in vivo noninvasive temperature measurements of carotid plaques, reflecting plaque inflammatory activation.
authors.affiliation: First Department of Cardiology, Hippokration Hospital, 26 Karaoli and Dimitriou str., Holargos, Athens, Greece. ktoutouz@otenet.gr
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Toutouzas
authors.forename: Charalampos
authors.initials: C
authors.lastname: Grassos
authors.forename: Maria
authors.initials: M
authors.lastname: Drakopoulou
authors.forename: Andreas
authors.initials: A
authors.lastname: Synetos
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Tsiamis
authors.forename: Constantina
authors.initials: C
authors.lastname: Aggeli
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Stathogiannis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Klettas
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Kavantzas
authors.forename: Georgios
authors.initials: G
authors.lastname: Agrogiannis
authors.forename: Efstratios
authors.initials: E
authors.lastname: Patsouris
authors.forename: Christos
authors.initials: C
authors.lastname: Klonaris
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Liasis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Tousoulis
authors.forename: Elias
authors.initials: E
authors.lastname: Siores
authors.forename: Christodoulos
authors.initials: C
authors.lastname: Stefanadis
mesh_terms: D000328:Adult; D000368:Aged; D001831:Body Temperature / Q000502:physiology*; D002339:Carotid Arteries; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D003937:Diagnosis, Differential; D016894:Endarterectomy, Carotid; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007249:Inflammation / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008872:Microwaves; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D011446:Prospective Studies; D011874:Radiometry / Q000379:methods*; D015203:Reproducibility of Results