title: Resistance index in benign prostatic hyperplasia using power Doppler imaging and clinical outcomes after transurethral vaporization of the prostate.
abstract: BACKGROUND
  Using power Doppler ultrasonography (PDUS), we investigate the change of resistance index (RI) before and after transurethral vaporization of the prostate (TUVP) in benign prostatic hyperplasia (BPH) patients.
  
  
  METHODS
  In all, 49 patients underwent transrectal PDUS before receiving TUVP, three were excluded because of cancer and three could not be followed up. The remaining 43 were enrolled in the present study. Patients were assessed before and 1, 3 and 6 months after surgery, giving a mean duration of follow-up of 9.1 months. International prostate symptom scores (IPSS), quality of life (QOL) scores, postvoiding residual urine volumes (PVR) and maximum urinary flow rates (Qmax) were evaluated and total prostatic volume (TPV) and RI were measured using PDUS.
  
  
  RESULTS
  Resistance index ranged from 0.64 to 0.91. The postoperative parameters except for RI, such as TPV, PVR, IPSS and QOL scores improved significantly at the follow-up assessment after surgery. The elevated RI decreased significantly 1, 3 and 6 months after the treatment. Resistance index significantly decreased after TUVP and IPSS and other urodymamics parameters improved.
  
  
  CONCLUSIONS
  The present study suggested that RI could evaluate the severity of BPH and the degree of intraprostatic pressure or bladder outlet obstruction.
authors.affiliation: Department of Urology, Hamamatsu University School of Medicine, Hamamatsu, Japan. tsuru@hama.med.ac.jp
authors.forename: Nobuo
authors.initials: N
authors.lastname: Tsuru
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kurita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Suzuki
authors.forename: Kimio
authors.initials: K
authors.lastname: Fujita
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019160:Endosonography; D006801:Humans; D008297:Male; D008875:Middle Aged; D011312:Pressure; D011470:Prostatic Hyperplasia / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D020728:Transurethral Resection of Prostate; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color; D001748:Urinary Bladder Neck Obstruction / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery