Defining the Degree of Intravesical Prostatic Protrusion in Association With Bladder Outlet Obstruction

다국어 초록 (Multilingual Abstract)

Purpose: The present study was done to define the degree of intravesical prostatic protrusion (IPP) causing bladder outlet obstruction (BOO) in patients with benign prostatic hyperplasia (BPH)/lower urinary tract symptoms.
Materials and Methods: We retrospectively evaluated 239 patients with BPH, analyzing age, IPP, prostate volume, International Prostate Symptom Score (IPSS), and the results from a pressure-flow study. Urethral resistance was quantified by using the BOO index (BOOI), according to the formula BOOI=PdetQmax-2×Qmax (where Pdet is detrusor pressure at the peak flow rate and Qmax is peak flow rate). BOO was defined by a BOOI above 40. Patients with a BOOI below 20 were excluded. Patients were classified into two groups (obstructed and unobstructed groups) by the BOOI. Correlations were determined by logistic regression analysis, and receiver operating characteristic curves were plotted to estimate the optimal cutoff for IPP.
Results: There were significant differences in total prostate volume, postvoiding residual urine (PVR), IPP, and Qmax (p＜0.001, p＜0.001, p＜0.001, and p=0.026, respectively)between the obstructed and unobstructed groups, but there were no significant differences in age (p=0.653), IPSS total score (p=0.624), or quality of life score (p=0.138). IPP had a significant prognosis (p＜0.001) but was weakly correlated with prostate volume (p=0.026). The correlation coefficients between IPP and Qmax, PVR,prostate volume, and BOO were 0.551, -0.159, 0.225, and 0.391, respectively. For IPP,the area under the curve was 0.759 (95% confidence interval, 0.657 to 0.861) and the cutoff to indicate BOO was 5.5 mm with 66.7% sensitivity and 80.5% specificity.
Conclusions: An IPP exceeding 5.5 mm was significantly associated with BOO.

참고문헌 (Reference)

1 el Din KE, "The correlation between bladder outlet obstruction and lower urinary tract symptoms as measured by the international prostate symptom score" 156 : 1020-1025, 1996

2 Lim CS, "The Abrams-Griffiths nomogram" 13 : 34-39, 1995

3 Mochtar CA, "Post-void residual urine volume is not a good predictor of the need for invasive therapy among patients with benign prostatic hyperplasia" 175 : 213-216, 2006

4 Klingler HC, "Morbidity of the evaluation of the lower urinary tract with transurethral multichannel pressure-flow studies" 159 : 191-194, 1998

5 Reis LO, "Intravesical protrusion of the prostate as a predictive method of bladder outlet obstruction" 34 : 627-633, 2008

6 Lee LS, "Intravesical prostatic protrusion predicts clinical progression of benign prostatic enlargement in patients receiving medical treatment" 17 : 69-74, 2010

7 Abrams P., "In support of pressure-flow studies for evaluating men with lower urinary tract symptoms" 44 : 153-155, 1994

8 Chia SJ, "Correlation of intravesical prostatic protrusion with bladder outlet obstruction" 91 : 371-374, 2003

9 Ezz el Din K, "Correlation between uroflowmetry, prostate volume, postvoid residue, and lower urinary tract symptoms as measured by the International Prostate Symptom Score" 48 : 393-397, 1996

10 Netto Junior NR, "Correlation between the International Prostatic Symptom Score and a pressure- flow study in the evaluation of symptomatic benign prostatic hyperplasia" 155 : 200-202, 1996

11 Keqin Z, "Clinical significance of intravesical prostatic protrusion in patients with benign prostatic enlargement" 70 : 1096-1099, 2007

12 Nose H, "Accuracy of two noninvasive methods of diagnosing bladder outlet obstruction using ultrasonography: intravesical prostatic protrusion and velocity-flow video urodynamics" 65 : 493-497, 2005