title: Comparisons of Three Indicators for Frey's Syndrome: Subjective Symptoms, Minor's Starch Iodine Test, and Infrared Thermography.
abstract: OBJECTIVE
  To correlate Frey's syndrome with subjective symptoms, Minor's starch iodine test results, and infrared thermography measurements, and to discuss the utility of thermography as a quantitative diagnostic method.
  
  
  METHODS
  This study included 59 patients who underwent unilateral parotidectomy. A subjective clinical questionnaire and an objective Minor's starch iodine test were performed to evaluate the incidence of Frey's syndrome. Infrared thermography was performed, and the subjects were divided into seven groups according to the temperature differences between operated and unoperated sites. The thermal differences were correlated with the results from Minor's starch iodine test and the subjective symptoms questionnaire.
  
  
  RESULTS
  Of the 59 patients, 20 patients (33.9%) reported subjective symptoms after eating; 30 patients (50.8%) tested positive for Minor's starch iodine test, 19 patients (63.3%) of which reported subjective symptoms. Of the 29 patients who were negative for the iodine test, 2 patients (6.9%) reported subjective symptoms. Thus, subjective symptoms were well correlated with Minor's starch iodine test (r=0.589, P<0.001). As the thermal differences with infrared thermography increased, the number of patients with subjective symptoms increased (χ(2)=22.5, P<0.001). Using infrared thermography, the mean temperature difference in the positive group for the iodine test was 0.82℃±0.26℃, and that in the negative group was 0.10℃±0.47℃. With increased thermal differences, more patients showed positivity in the iodine test (χ(2)=29.9, P<0.001).
  
  
  CONCLUSIONS
  Subjective symptoms, Minor's starch iodine test, and infrared thermography are well correlated with one another. Quantitative thermography provides clues for the wide variation in the incidence of Frey's syndrome, and could be a useful method for diagnosing and studying Frey's syndrome.
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Hyo Geun
authors.initials: HG
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Sae Young
authors.initials: SY
authors.lastname: Kwon
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Jung Youn
authors.initials: JY
authors.lastname: Won
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Yoo
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Min Gu
authors.initials: MG
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Si Whan
authors.initials: SW
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, Hallym University Sacred Heart Hospital, Anyang, Korea.
authors.forename: Bumjung
authors.initials: B
authors.lastname: Park
keywords: Frey's syndrome; Gustatory; Parotid gland; Sweating; Thermography