title: Impact of prostate volume on the efficacy of high-power potassium-titanyl-phosphate photoselective vaporization of the prostate: a retrospective, short-term follow-up study on evaluating feasibility and safety.
abstract: OBJECTIVE
  We determined the impact of prostate volume on the efficacy of the high-power (80 W) potassium-titanyl-phosphate (KTP) photoselective laser vaporization of the prostate in men with lower urinary tract symptoms (LUTS).
  
  
  METHODS
  Patients were stratified into 3 groups according to prostate volume: '< 40 g' (n = 49) and '40-59 g' (n = 49) and '≥ 60 g' (n = 22). Median follow-up was 9 months (range 6 to 21).
  
  
  RESULTS
  No differences in age and follow-up duration were observed in the three groups. At baseline, no significant differences were noted in the three groups in terms of the International Prostate Symptom Score (IPSS) (21.4, 19.4 and 19.1; p = 0.412) as well as the maximum flow rate (Qmax) (10.2, 9.2, and 8.6 mL/s; p = 0.291) and post-void residual (PVR) (66.2, 80.4, and 71.5 mL; p = 0.856). The mean operative times were 30.9, 46.9, and 58.6 minutes (p< 0.001) and total median energy deliveries for each group were 62.3, 97.6, and 135.9 kJ, respectively (p< 0.001). No severe intraoperative complication was observed. At the last follow-up, these parameters improved significantly regardless of prostate volume, and the IPSS (11.1, 9.4, and 12.3; p = 0.286) as well as Qmax (15.9, 15.9, and 14.2 mL/s; p = 0.690) and PVR (33.7, 28.4, and 14.2 mL; p = 0.395) were not significantly different among the groups.
  
  
  CONCLUSIONS
  Although a larger prostate requires more time and energy delivery, photoselective laser vaporization of the prostate is safe and efficacious for patients with LUTS regardless of prostate volume.
authors.affiliation: Department of Urology, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ja Hyeon
authors.initials: JH
authors.lastname: Ku
authors.forename: Soo Woong
authors.initials: SW
authors.lastname: Kim
authors.forename: Jae-Seung
authors.initials: JS
authors.lastname: Paick
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005240:Feasibility Studies; D006801:Humans; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000737:chemistry*; D011467:Prostate / Q000502:physiology* / Q000601:surgery; D017430:Prostate-Specific Antigen / Q000097:blood; D011470:Prostatic Hyperplasia / Q000150:complications / Q000601:surgery*; D012189:Retrospective Studies; D014025:Titanium / Q000737:chemistry*; D016896:Treatment Outcome; D014551:Urinary Tract / Q000473:pathology; D014835:Volatilization
chemical_list: D010710:Phosphates; C064806:potassium titanylphosphate; D014025:Titanium; D017430:Prostate-Specific Antigen