title: Median nerve ultrasound in diabetic peripheral neuropathy with and without carpal tunnel syndrome.
abstract: BACKGROUND
  Median nerve ultrasound shows increased cross-sectional area (CSA) in carpal tunnel syndrome (CTS) and diabetic peripheral neuropathy (PN). The role of ultrasound in diagnosing CTS superimposed on diabetic PN is unknown. The objective of this study is to evaluate ultrasound for diagnosis of CTS in diabetic PN.
  
  
  METHODS
  Prospective recruitment of diabetics with electrodiagnostically proven PN, subdivided into cases (with CTS) or controls (without CTS). The gold standard for CTS was clinical diagnosis. NCS were correlated with blinded median nerve CSA ultrasound measurements.
  
  
  RESULTS
  Eight cases (CTS) and eight controls (no CTS) were recruited. Nerve conduction studies (NCS): Median nerve distal latencies (antidromic sensory; palmar; lumbrical motor; and lumbrical motor to ulnar interosseous difference) were significantly prolonged in CTS cases. No ultrasound measurement (distal median CSA, wrist-forearm ratio, wrist-forearm difference) reached significance to detect CTS. Area under the curve was greatest for lumbrical distal latency by receiver operator characteristic analysis (0.85).
  
  
  CONCLUSIONS
  In this pilot study, NCS may be superior to ultrasound for identification of superimposed CTS in diabetic PN patients, but larger numbers are needed for confirmation.
authors: Department of Neurophysiology, Mayo Clinic, 200 First Street SW, Rochester, Minnesota 55905, USA.
authors: Anhar
authors: A
authors: Hassan
authors: Andrea N
authors: AN
authors: Leep Hunderfund
authors: James
authors: J
authors: Watson
authors: Andrea J
authors: AJ
authors: Boon
authors: Eric J
authors: EJ
authors: Sorenson
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging*; D003929:Diabetic Neuropathies / Q000000981:diagnostic imaging*; D004568:Electrodiagnosis; D005260:Female; D005385:Fingers / Q000294:innervation; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology; D009460:Neurologic Examination; D010525:Peripheral Nerves / Q000000981:diagnostic imaging*; D010865:Pilot Projects; D011446:Prospective Studies; D012372:ROC Curve; D014463:Ultrasonography; D055815:Young Adult