title: Objective assessment of C-fiber function by electrically induced axon reflex flare in patients with axonal and demyelinating polyneuropathy.
abstract: BACKGROUND
  A simple test to evaluate the peripheral C-fiber function is the measurement of axon reflex flare area. In this study, we compared the flare area in healthy subjects and in two groups of patients with predominantly axonal or demyelinating polyneuropathy.
  
  
  METHODS
  We examined 42 control subjects and 33 patients. The flare responses were elicited by the application of transcutaneous electrical stimulation and recorded by laser Doppler imaging.
  
  
  RESULTS
  There was a significant reduction of electrically induced flare area in both groups of neuropathy patients (P < 0.001; analysis of covariance). Interestingly, patients with an axonal neuropathy had a significantly stronger reduction of flare size as compared to patients with demyelinating neuropathy (P = 0.03).
  
  
  CONCLUSIONS
  The evaluation of the axon flare response in the arm can be used as a screening test of impaired C-fiber function in polyneuropathy patients with the advantages of simplicity of the procedure and time economy.
authors.affiliation: Laboratory of Electromyography and Clinical Neurophysiology, Department of Neurology, Aeginition Hospital, University of Athens, Athens, Greece. pkokotis@med.uoa.gr
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kokotis
authors.forename: Martin
authors.initials: M
authors.lastname: Schmelz
authors.forename: Aikaterini E
authors.initials: AE
authors.lastname: Papagianni
authors.forename: Thomas
authors.initials: T
authors.lastname: Zambelis
authors.forename: Nikos
authors.initials: N
authors.lastname: Karandreas
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001369:Axons / Q000000981:diagnostic imaging*; D003711:Demyelinating Diseases / Q000503:physiopathology*; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods; D004568:Electrodiagnosis / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005542:Forearm / Q000503:physiopathology; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D036421:Nerve Fibers, Unmyelinated / Q000000981:diagnostic imaging*; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology; D011115:Polyneuropathies / Q000503:physiopathology*; D012018:Reflex / Q000502:physiology*; D018608:Ultrasonography, Doppler; D055815:Young Adult