title: Analysis of human ejaculation using color Doppler ultrasonography: a comparison between antegrade and retrograde ejaculation.
abstract: OBJECTIVE
  To observe the phenomenon of human ejaculation dynamically using color Doppler ultrasonography.
  
  
  METHODS
  Human ejaculation was observed using transrectal color Doppler ultrasonography in a healthy man and a patient with retrograde ejaculation. Ejaculation was induced manually with audiovisual sexual stimulation. The ejaculatory phenomenon was analyzed and compared with that of retrograde ejaculation.
  
  
  RESULTS
  In the healthy man, the prostatic urethra flattened slightly and the bladder neck contracted just before expulsion. The ejaculatory stream spurted from the seminal vesicles to the bulbous urethra through the ejaculatory duct. In the patient with retrograde ejaculation, the ejaculatory stream from the seminal vesicles and inframontanal and distal prostatic urethras distended into a globular-shaped sac filled with semen. No seminal flow toward the bulbous urethra occurred. The semen remaining in the prostatic urethra began flowing slowly into the bladder.
  
  
  CONCLUSIONS
  Differences between antegrade and retrograde ejaculation can be clearly detected by color Doppler ultrasonography, providing a noninvasive method to diagnose ejaculatory disorders.
authors.affiliation: Department of Urology, Okayama University Graduate School of Medicine and Dentistry, Okayama, Okayama Prefecture, Japan. atsnagai@md.okayama-u.ac.jp
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nagai
authors.forename: Masami
authors.initials: M
authors.lastname: Watanabe
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Nasu
authors.forename: Hiroki
authors.initials: H
authors.lastname: Iguchi
authors.forename: Norihiro
authors.initials: N
authors.lastname: Kusumi
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kumon
mesh_terms: D000328:Adult; D004542:Ejaculation / Q000187:drug effects / Q000502:physiology*; D005837:Genitalia, Male / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D010413:Penis / Q000000981:diagnostic imaging; D011467:Prostate / Q000098:blood supply / Q000000981:diagnostic imaging; D012669:Seminal Vesicles / Q000000981:diagnostic imaging; D013119:Spinal Cord Injuries / Q000150:complications; D013904:Thoracic Vertebrae; D013997:Time Factors; D018615:Ultrasonography, Doppler, Color; D014521:Urethra / Q000000981:diagnostic imaging*; D001743:Urinary Bladder / Q000000981:diagnostic imaging*