title: Thermal Disparity between Fingers after Cold-water Immersion of Hands: A Useful Indicator of Disturbed Peripheral Circulation in Raynaud Phenomenon Patients.
abstract: OBJECTIVE
  To devise an effective method to assess the peripheral circulation using an infrared thermographic analysis.
  
  
  METHODS
  Sequential measurements of the skin temperature before and after cold-water immersion of the hands were analyzed by a thermographic examination in healthy controls and patients diagnosed to have Raynaud phenomenon (RP). The skin temperatures of the dorsum of all fingernail folds and the metacarpophalangeal (MCP) joints were measured at baseline. Then the hands were immersed in 10°C water for 10 s, and the skin temperatures were measured at 0, 3, 5, 10, 15, 20 and 30 min after immersion. The mean temperature, recovery rate and disparity (coefficient of variation) of the nail fold temperatures were calculated. The distal-dorsal difference (DDD) was calculated by subtracting the mean MCP temperature from the mean nail fold temperature. Receiver operating characteristic (ROC) curves were generated to compare these parameters in terms of their capability to differentiate patients with RP.
  
  
  RESULTS
  Thirty-one RP patients and 25 controls were included in the study. The baseline nail fold temperature was significantly lower in RP patients than in the controls. The RP patients had a lower recovery rate, lower DDD and higher disparity than the controls. The disparity and DDD were negatively correlated (r=-0.63, p<0.01), whereas the recovery rate and DDD were positively correlated (r=0.91, p<0.01). The ROC curve analysis revealed that the disparity in nail fold temperature effectively differentiated RP patients from controls (area under the curve: recovery rate 0.72; disparity 0.88; DDD 0.79).
  
  
  CONCLUSIONS
  The temperature disparity between fingers is a useful thermographic parameter for evaluating disturbed peripheral circulation in patients with Raynaud phenomenon.
authors.affiliation: Department of Allergy and Rheumatic Diseases, Japanese Red Cross Medical Center, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Horikoshi
authors.forename: Shigeko
authors.initials: S
authors.lastname: Inokuma
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kijima
authors.forename: Mika
authors.initials: M
authors.lastname: Kobuna
authors.forename: Yoko
authors.initials: Y
authors.lastname: Miura
authors.forename: Rika
authors.initials: R
authors.lastname: Okada
authors.forename: Shoko
authors.initials: S
authors.lastname: Kobayashi
mesh_terms: D000328:Adult; D001775:Blood Circulation; D003080:Cold Temperature; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006225:Hand / Q000098:blood supply; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D011928:Raynaud Disease / Q000175:diagnosis* / Q000503:physiopathology; D012189:Retrospective Studies; D012881:Skin Temperature; D013817:Thermography; D014867:Water
chemical_list: D014867:Water