title: Pathophysiology inferred from electrodiagnostic nerve tests and classification of polyneuropathies. Suggested guidelines.
abstract: OBJECTIVE
  To present criteria for pathophysiological interpretation of motor and sensory nerve conduction studies and for pathophysiological classification of polyneuropathies suggested by a group of European neurophysiologists.
  
  
  METHODS
  Since 1992 seven neurophysiologists from six European countries have collected random samples of their electrodiagnostic examinations for peer review medical audit in the ESTEEM (European Standardized Telematic tool to Evaluate Electrodiagnostic Methods) project. Based on existing criteria in the literature, the experience with a patient material of 572 peer reviewed electrodiagnostic examinations, and productive discussions between the physicians at workshops, the collaboration has produced a set of criteria now routinely used at the centres involved in the project.
  
  
  RESULTS
  The first part of the paper considers pathophysiology of individual nerve segments. For interpretation of motor and sensory nerve conduction studies, figures showing change in amplitude versus change in conduction velocity/distal latency and change in F-wave frequency versus change in F-wave latency are presented. The suggested boundaries delimit areas corresponding to normal, axonal, demyelinated, or neuropathic nerve segments. Criteria for motor conduction block in upper and lower extremities are schematically depicted using the parameters CMAP amplitude and CMAP duration. The second part of the paper suggests criteria for classification of polyneuropathies into axonal, demyelinating, or mixed using the above-mentioned criteria.
  
  
  CONCLUSIONS
  The suggested criteria are developed during many years of collaboration of different centres and may be useful for standardization in clinical neurophysiology.
  
  
  CONCLUSIONS
  Consistent interpretation of nerve conduction studies is an important step in optimising diagnosis and treatment of nerve disorders.
authors.affiliation: Department of Neurophysiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Hatice
authors.initials: H
authors.lastname: Tankisi
authors.forename: Kirsten
authors.initials: K
authors.lastname: Pugdahl
authors.forename: Anders
authors.initials: A
authors.lastname: Fuglsang-Frederiksen
authors.forename: Birger
authors.initials: B
authors.lastname: Johnsen
authors.forename: Mamede
authors.initials: M
authors.lastname: de Carvalho
authors.forename: Peter R W
authors.initials: PR
authors.lastname: Fawcett
authors.forename: Annick
authors.initials: A
authors.lastname: Labarre-Vila
authors.forename: Rocco
authors.initials: R
authors.lastname: Liguori
authors.forename: Wilfred A
authors.initials: WA
authors.lastname: Nix
authors.forename: Ian S
authors.initials: IS
authors.lastname: Schofield
mesh_terms: D001369:Axons / Q000502:physiology; D016208:Databases, Factual / Q000639:trends; D003711:Demyelinating Diseases / Q000175:diagnosis / Q000503:physiopathology; D004493:Education; D004568:Electrodiagnosis / Q000379:methods / Q000592:standards*; D004594:Electrophysiology / Q000379:methods / Q000592:standards*; D005060:Europe; D009477:Hereditary Sensory and Autonomic Neuropathies / Q000145:classification / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D007391:International Cooperation; D009046:Motor Neurons / Q000502:physiology; D009431:Neural Conduction / Q000502:physiology*; D009460:Neurologic Examination; D009475:Neurons, Afferent / Q000502:physiology; D009482:Neurophysiology / Q000379:methods / Q000592:standards*; D010525:Peripheral Nerves / Q000503:physiopathology*; D011115:Polyneuropathies / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology*; D011446:Prospective Studies; D011930:Reaction Time / Q000502:physiology; D012985:Software Design