title: Sonographic examination of the median nerve in dialysis patients and after renal transplantation.
abstract: OBJECTIVE
  Patients with renal insufficiency are predisposed to develop CTS (carpal tunnel syndrome). In particular, long-term dialysis seems to contribute to changes in median nerve texture which lead to an increased risk for CTS. The current study was designed to evaluate if these structural changes can be detected by HRS (high-resolution sonography). Additionally, the current study aimed to determine if changes are reversible after termination of dialysis.
  
  
  METHODS
  Fifty patients (98 hands) were included in the study. The study population was subdivided into three groups: patients without any history of renal disease (H, n = 20), patients with long-term dialysis (D, n = 10), and patients after renal transplantation (TX, n = 20). None of the patients had any clinical symptoms for a median nerve compression syndrome. The CSA (cross-sectional area) of the median nerve was evaluated both 12 cm proximally of the carpal tunnel inlet and directly at the carpal tunnel inlet. The ratio of those two values, the WFR (wrist forearm ratio), was calculated and analyzed.
  
  
  RESULTS
  The CSA demonstrated significantly higher values in dialysis (D) and transplanted (TX) patients compared to the healthy (H) control group (P < 0.001). No significant differences were detectable between the D and TX groups. Specifically, there was no significant difference in the WFR.
  
  
  CONCLUSIONS
  Patients with chronic renal disease demonstrate significantly higher CSA values compared to their healthy counterparts. Termination of dialysis does not seem to reverse these morphological changes.
authors.affiliation: Department of Neurosurgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Anne Elisabeth
authors.initials: AE
authors.lastname: Carolus
authors.affiliation: Department of General, Visceral and Transplant Surgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Schenker
authors.affiliation: Center for Peripheral Nerve Surgery Dossenheim-Heidelberg Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dombert
authors.affiliation: Department of Neurosurgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Johann
authors.initials: J
authors.lastname: Fontana
authors.affiliation: Department of General, Visceral and Transplant Surgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Richard
authors.initials: R
authors.lastname: Viebahn
authors.affiliation: Department of Neurosurgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Schmieder
authors.affiliation: Department of Neurosurgery University Hospital Knappschaftskrankenhaus Bochum Ruhr-University Bochum Bochum Germany.
authors.forename: Christopher
authors.initials: C
authors.lastname: Brenke
mesh_terms: D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000150:complications / Q000000981:diagnostic imaging; D005260:Female; D007839:Functional Laterality; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging*; D008875:Middle Aged; D009929:Organ Size; D011446:Prospective Studies; D006435:Renal Dialysis; D051437:Renal Insufficiency / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy*; D014463:Ultrasonography
keywords: Carpal tunnel syndrome; cross‐sectional area; dialysis; median nerve; renal transplantation; ultrasonography