title: Objective tests for upper motor neuron involvement in amyotrophic lateral sclerosis (ALS).
abstract: OBJECTIVE
  To develop objective markers for upper motor neuron (UMN) involvement in ALS, the value of single-voxel MR spectroscopy (MRS) and transcranial magnetic stimulation (TMS) was studied.
  
  
  METHODS
  Test results of 164 ALS patients who had MRS only (n = 91), TMS only (n = 13), or both (n = 60) were analyzed; also, 11 autopsy examinations were evaluated.
  
  
  RESULTS
  Abnormal test results consistent with UMN involvement were found in 134 patients with clinical UMN signs: 86% on MRS, 77% on TMS, and 70% on MRS and TMS together. Among 30 patients with solely LMN signs (progressive muscular atrophy), UMN results were found in 63% on MRS, 63% on TMS, and 46% on both tests together. There was a significant association of the degree of abnormal N-acetyl aspartate/creatine ratios with UMN signs (p = 0.01). The sensitivity to detect UMN involvement was 0.86 for MRS (specificity 0.37) and 0.77 for TMS (specificity 0.38). At autopsy, all 11 patients had pathologic UMN abnormalities, including 4 with normal MRS and 1 with normal TMS in life.
  
  
  CONCLUSIONS
  MRS is highly sensitive, somewhat more than TMS, and shows good correlation with clinical UMN signs. Combining MRS and TMS results in the same patient with further refinement may help in the early diagnosis of ALS.
authors.affiliation: Eleanor and Lou Gehrig MDA/ALS Research Center, Neurologic Institute, Department of Neurology, Columbia University, New York 10032, USA. pk88@columbia.edu
authors.forename: P
authors.initials: P
authors.lastname: Kaufmann
authors.forename: S L
authors.initials: SL
authors.lastname: Pullman
authors.forename: D C
authors.initials: DC
authors.lastname: Shungu
authors.forename: S
authors.initials: S
authors.lastname: Chan
authors.forename: A P
authors.initials: AP
authors.lastname: Hays
authors.forename: M L
authors.initials: ML
authors.lastname: Del Bene
authors.forename: M A
authors.initials: MA
authors.lastname: Dover
authors.forename: M
authors.initials: M
authors.lastname: Vukic
authors.forename: L P
authors.initials: LP
authors.lastname: Rowland
authors.forename: H
authors.initials: H
authors.lastname: Mitsumoto
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D005500:Follow-Up Studies; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008280:Magnetics; D009046:Motor Neurons / Q000502:physiology*; D009128:Muscle Spasticity / Q000175:diagnosis; D009460:Neurologic Examination / Q000379:methods*; D011237:Predictive Value of Tests; D011712:Pyramidal Tracts / Q000473:pathology; D012021:Reflex, Abnormal; D001405:Reflex, Babinski; D012026:Reflex, Stretch; D012189:Retrospective Studies