Preoperative and postoperative patient evaluation
In these patients, validated Korean version of International Prostate Symptom Score (I-PSS) questionnaires were acquired preoperatively16. Prostate volume measurement using trans-rectal ultrasonography, serum prostate specific antigen (PSA) level examination, and uroflowmetry with post-voided residual urine were also performed prior to surgery. In addition, UDS was routinely performed before the surgery. At postoperative 1, 6, 12, 24, 36, 48, and 60 months, I-PSS questionnaires and uroflowmetry with post-void residual urine were evaluated. Serum PSA level and prostate volume were measured at postoperative 6 months.