title: Comparison of deep biopsy tissue damage from transurethral resection of bladder tumors between bipolar and monopolar devices.
abstract: OBJECTIVE
  Bipolar energy has recently been used for transurethral resection of bladder tumor (TURBT). Although this modality is thought to be safe, there are some controversies concerning the pathologic accuracy of the biopsy specimens. We compared clinical efficacy, safety, and pathologic characteristics of deep biopsy specimens between bipolar and monopolar devices.
  
  
  METHODS
  From January 2002 to June 2007, a total of 115 patients underwent TURBT with deep biopsy with the use of bipolar (bipolar group, n=64) or monopolar (monopolar group, n=51) devices. We retrospectively analyzed tumor size, tumor number, urine cytology, perioperative blood loss (postoperative changes in hemoglobin levels), complications, duration of catheterization, duration of hospitalization, pathologic stage, WHO grade, deep biopsy specimen thickness, and grade of thermal damage.
  
  
  RESULTS
  There were no statistical differences in tumor size, tumor number, urine cytology, complications, duration of hospitalization, pathologic stage, or WHO grade between the two groups. Postoperative changes in hemoglobin levels were significantly lower in the bipolar group (p=0.038), and the duration of catheterization was shorter in the bipolar group (p=0.026). The deep biopsy specimen thickness was significantly thinner in the bipolar group (2.25±0.94 mm vs. 3.02±1.39 mm, p<0.05). The grade of thermal damage was not statistically different between the two groups (p=0.862).
  
  
  CONCLUSIONS
  In terms of clinical efficacy and safety, bipolar TURBT is comparable to monopolar TURBT, having advantages in perioperative blood loss and duration of catheterization. In addition, pathologic changes in deep biopsy after bipolar and monopolar TURBT are similar. Bipolar TURBT can be properly used for bladder tumors without pathologic error.
authors.affiliation: Department of Urology, College of Medicine, Yeungnam University, Daegu, Korea.
authors.forename: So Jun
authors.initials: SJ
authors.lastname: Yang
authors.forename: Phil Hyun
authors.initials: PH
authors.lastname: Song
authors.forename: Hyun Tae
authors.initials: HT
authors.lastname: Kim