Correlation between prostatic urethral angulation and symptomatic improvement after surgery in patients with lower urinary tract symptoms according to prostate size

Purpose To investigate the effect of prostate anatomical factors on the changes in lower urinary tract symptoms (LUTS) and uroflowmetric values after surgery. Methods The medical records of 448 patients who underwent transurethral resection of the prostate (TURP) from January 2006 to December 2018 were analyzed retrospectively. Changes in the International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), and post-void residual urine volume (PVR) at 3 months after TURP were evaluated. Prostate volume, intravesical prostatic protrusion (IPP), and prostatic urethral angulation (PUA) were measured using transrectal ultrasonography, and their effect on the changes in LUTS after TURP was analyzed using multivariable linear regression. Results Among patients with prostate volume < 50 mL, preoperative IPSS total score (IPSS-t), voiding symptom score (IPSS-vs), and storage symptom score (IPSS-ss) were significantly better in patients with a smaller PUA (< 51 degrees) than in those with a larger PUA (>= 51 degrees) (p = 0.001, < 0.001, and 0.020, respectively). Changes in IPSS-t, IPSS-vs, IPSS-ss, and PVR at 3 months after TURP were significantly correlated with PUA (p <= 0.001, < 0.001, 0.048, and 0.012, respectively). Multivariable linear regression revealed PUA to be independently associated with changes in IPPS-t and IPSS-vs (p = 0.025 and < 0.001, respectively) only in patients with prostate volume < 50 mL. Conclusion Prostatic urethral angulation was significantly associated with postoperative changes in LUTS only in patients with small prostate, and had no clinical significance in patients with large prostate. In patients with small prostate and large PUA, surgery should actively be considered.