title: Nocturnal electrobioimpedance volumetric assessment of patients with erectile dysfunction.
abstract: OBJECTIVE
  Electrobioimpedance volumetric assessment is a procedure that can measure penile length, cross-sectional area, and volume. From these variables, the number and duration of erectile events, volume change, and percentage of volume increase from baseline can be determined. This procedure was performed on patients with erectile dysfunction (ED) and findings were compared with patients with no history of ED. Examples of etiology are reported.
  
  
  METHODS
  Two groups of patients with ED were evaluated by electrobioimpedance assessment. Group 1 patients (n = 23), ranging in age from 26 to 60 years (mean 50), were involved in simultaneous electrobioimpedance assessment and duplex Doppler ultrasound penile volume measurements. A tissue correction was derived. Group 2 patients (n = 10), ranging in age from 38 to 64 years (mean 50), used nocturnal electrobioimpedance volumetric assessment (NEVA) at home for 2 consecutive nights.
  
  
  RESULTS
  After deriving an expression to correct for tissue volume, simultaneous measurement of penile blood volume by NEVA and duplex Doppler showed that the regression line for study participants and the identity line was not significantly different by analysis of variance. Using NEVA in comparing patients with ED to a reference population with no history of ED, and using a two-tailed Student's t test for means, the data demonstrated a statistically significant (P < or =0.05) difference in the number of erectile events and percentage of volume change over baseline. With NEVA data, it was possible to distinguish arterial insufficiency from veno-occlusive dysfunction.
  
  
  CONCLUSIONS
  The present study demonstrates that electrobioimpedance volumetric assessment can be used in patients with ED. Compared with a reference population with no history of ED, the group with ED had fewer nocturnal erectile events that resulted in a smaller increase in penile blood volume change over baseline. Although the time dependence of the measured variables identifies the cause of ED, the application of NEVA to a larger population will allow further analysis of the dynamic information contained in the NEVA data.
authors.affiliation: Center for Urological Treatment and Research, Nashville, Tennessee 37203, USA.
authors.forename: L D
authors.initials: LD
authors.lastname: Knoll
authors.forename: J H
authors.initials: JH
authors.lastname: Abrams
mesh_terms: D000328:Adult; D017097:Electric Impedance; D007172:Erectile Dysfunction / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010413:Penis / Q000098:blood supply / Q000503:physiopathology; D012039:Regional Blood Flow; D012890:Sleep