Comparisons were made between the two groups of patients in such demographic and baseline data as age , comorbidity , body mass index ( BMI ) , serum prostate-specific antigen ( PSA ) , prostate volume , bioptic Gleason score , clinical stage , IIEF-5 score , nocturnal penile tumescence ( NPT ) , penile brachial index ( PBI ) , and penile arterial blood flow velocity as well as in such surgery-related parameters as operation duration , blood loss , blood transfusion , intraoperative complications , positive surgical margin , catheterization time , hospital stay , and postoperative Gleason score , pathologic stage , urinal pad use , PSA level , IIEF-5 score , NPT , PBI and PABFV .