title: Serial electrophysiological studies in a Guillain-Barré subtype with bilateral facial neuropathy.
abstract: OBJECTIVE
  Bifacial weakness with paraesthesias subtype of Guillain-Barré syndrome (GBS) is thought to be demyelinating in nature but the evolution of serial nerve conduction study (NCS) findings has not been studied. We retrospectively analyzed the changes on serial NCS of patients with bilateral facial neuropathy.
  
  
  METHODS
  We described the clinical features, serial blink reflex, facial nerve and limb NCS of such patients.
  
  
  RESULTS
  Five patients fulfilled our study criteria. Patients 1 and 2 were diagnosed clinically to have bilateral Bell's palsy, patients 3 and 4 as bifacial GBS subtype and patient 5 as facial palsy associated with acute HIV infection. In all, the initial neurophysiological tests showed absent blink response and normal facial NCS. Patient 1's repeat tests were normal. Patient 2's repeat blink reflex showed mildly prolonged latency. Repeat blink reflex latency of patients 3, 4 and 5 were in the demyelinating range. Patient 3 also had prolonged facial nerve latency. Patients 3 and 4 had serial limb NCS showing progressively prolonged latency.
  
  
  CONCLUSIONS
  Serial NCS suggests that the bifacial GBS subtype is demyelinating in nature.
  
  
  CONCLUSIONS
  This study provides further evidence for a bifacial subtype of GBS with a demyelinating pathophysiology.
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Neurology, National University Hospital, Singapore. Electronic address: yee_cheun_chan@nuhs.edu.sg.
authors.forename: Yee-Cheun
authors.initials: YC
authors.lastname: Chan
authors.affiliation: Division of Neurology, National University Hospital, Singapore. Electronic address: madacamy_aravinda_kannan@nuhs.edu.sg.
authors.forename: Aravind-Kannan
authors.initials: AK
authors.lastname: Therimadasamy
authors.affiliation: Division of Neurology, National University Hospital, Singapore. Electronic address: maisarah_sainuddin@nuhs.edu.sg.
authors.forename: Nurul M
authors.initials: NM
authors.lastname: Sainuddin
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Division of Neurology, National University Hospital, Singapore. Electronic address: einar_wilder-smith@nuhs.edu.sg.
authors.forename: Einar
authors.initials: E
authors.lastname: Wilder-Smith
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address: gbs.yuki.cidp@gmail.com.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yuki
mesh_terms: D000328:Adult; D001767:Blinking / Q000502:physiology*; D005154:Facial Nerve / Q000473:pathology / Q000502:physiology; D005155:Facial Nerve Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D020275:Guillain-Barre Syndrome / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011446:Prospective Studies; D012189:Retrospective Studies
keywords: Bell’s palsy; Bifacial weakness with paraesthesias; Guillain–Barré syndrome; Neurophysiological studies