Which Is a Better Indicator of Bladder Outlet Obstruction in Patients with Benign Prostatic Enlargement – Intravesical Protrusion of Prostate or Bladder Wall Thickness?
Damir Aganovic, Munira Hasanbegovic, Alden Prcic, Benjamin Kulovac, Osman Hadziosmanovic
Med Arh. 2012; 66(5): 324-328
Objective: to determine the correlation of intravesical prostatic protrusion (IPP) and bladder wall thickness (BWT) with clinical and urodynamic parameters, as well as their sensitivity and specificity with regard to bladder outlet obstruction in patients with a benign prostatic enlargement (BPE). Materials and methods: 111 patients with lower urinary tract symptoms and confirmed BPE completed the International Prostatic Symptom Score (I-PSS), as well as a transabdominal ultrasound to determine their prostate volume, a grade of IPP and BWT. All the patients were then subjected to the complete urodynamic studies (UDS). Results: the IPP showed a good correlation with the prostate volume (r=0.61) and serum PSA (r=0.48); p=0.0000, free uroflowmetry (r=-0.27; p=0.004), as well as the determinants of urodynamic obstruction: bladder outlet obstruction index–BOOI (r=0.36; p<0.0001), and ICS and Schaefer obstruction class nomograms (rho=0.33 and rho=0.39, respectively; p<0.001), while the BWT showed only a statistical correlation with age (r=0.23; p=0.02) and serum PSA (r=0.4; ,p=0.0000), regardless of an significant correlation with the IPP (r=0.45; p=0.0000). The ANOVA test showed a significant difference between the IPP grades for the observed clinical and urodynamic variables with an increase in significance for IPP>10 mm. The area under the ROC curve in the prediction of obstruction for the IPP is 0.71 (sensitivity 59.6, specificity 81.4), while the AUC for the BWT is 0.61 (sensitivity 64.5, specificity 59.2). The stepwise logistic regression model shows that most significant independent variables for the obstruction are the IPP, Qmaxfree and age, with the area under the ROC curve of 0.78 (95% CI 0.695 to 0.856). Conclusion: The IPP higher than 10 mm as a non-invasive predictor of infravesical obstruction shows good correlations with clinical and urodynamic parameters, while the specificity and PPV against obstruction are significant. Despite a good correlation with IPP, the BWT is only a modest indicator of obstruction.
1. Briganti A, Capitanio U, Suardi N, et al. Benign prostatic hyperplasia and its aetiologies, Eur Urol Suppl. 2009; 8: 865-871.
2. Huang Foen Chung JW, Spigt MG, Knottnerus JA, van Mastrigt R. Comparative analysis of the reproducibility and applicability of the condom catheter method for noninvasive urodynamics in two Dutch centers, Urol Int. 2008; 81: 139-148.
3. Abrams P, Griffiths D, Hofner K, et al. The urodynamics of LUTS. In: Chatelain C, Denis L, Foo KT, et al. editors, Benign prostatic hyperplasia. Plymouth, UK: Health Publications, 2001: 227-281.
4. Belal M, Abrams P. Noninvasive method of diagnosis bladder outlet obstruction in men. Part 1: Non urodynamic approach, J Urol. 2006; 176: 22-28.
5. Chia SJ, Heng CT, Chan SP, Foo KT. Correlation of intravesical prostatic protrusion with bladder outlet obstruction, BJU Inter. 2003; 91: 371-374.
6. Oelke M, Hofner K, Wiese B, Grunewald V, Jonas U. Increase in detrusor wall thickness indicates bladder outlet obstruction (BOO) in men, Worl J Urol. 2002; 19: 443-452.
7. Abrams P. Urodynamics in clinical practice. In: Urodynamics, edited by Abrams P, Springer–Verlag, London, 2000, second edition, (Ch.5): 148-172.
8. Abrams P. Bladder outlet obstruction index, bladder contractility index and bladder voiding efficiency: three simple indices to define bladder voiding dysfunction, BJU Inter. 1999; 84: 14-15.
9. Abrams P, Cardozo L, Fall M, Griffiths D, Rosier P, Ulmsten U, et al. The standardisation of terminology of lower urinary tract function: report from the standardisation sub-committee of the international continence society, Neurourol Urodyn. 2002; 21: 167-178.
10. El Din KE, Kiemeney LALM, De Wildt MJAM, Rosier PFWM, Debruyne FMJ, de la Rosette JJMCH. Correlation between uroflowmetry, postvoided residual, and lower urinary tract symptoms as measured by the International Prostate Symptom Score, Urology, 1996; 48: 393–397.
11. Kuo HC. Clinical prostate score for diagnosis of bladder outlet obstruction by prostate measurements and uroflowmetry, Urology. 1999; 54: 90-96.
12. Reis LO, Barreior GC, Baracat J, Prudente A, D’Ancona CA. Intravesical protrusion of the prostate as a predictive method of bladder outlet obstruction, Inter Braz J Urol. 2008; 34(5): 627-637.
13. Lieber MM, Jacobson DJ, McGree ME, St Sauver JL, Girman CJ, Jacobsen SJ. Intravesical prostatic protrusion in men in Olmsted County, Minnesota, J Urol. 2009: 182(6): 2819-2824.
14. Kim KH, Kim YS. Correlation of Male Overactive Bladder with Intravesical Prostatic Protrusion, Korean J Urol. 2010;, 51(12): 843-846.
15. Franco G, De Nunzio C, Leonardo C, Tubaro A, Ciccariello M, De Dominicis C, Miano L, Laurenti C. Ultrasound assessment of intravesical prostatic protrusion and detrusor wall thickness-new standards for noninvasive bladder outlet obstruction diagnosis? J Urol. 2010; 183(6): 2270-2274.
16. Han WK, Shan GZ, Jin J. Correlation of intravesical prostatic protrusion with clinical evaluation parameters in BPH patients. Zhonghua Nan Ke Xue. 2010; 16(3): 254-257.
17. Kim BH, Sohn JC, Park CH, Kim CI. The Usefulness of Intravesical Prostatic Protrusion and Bladder Wall Thickness Measurement Using Transabdominal Ultrasound in Patients with Benign Prostatic Hyperplasia. Korean J Urol. 2005; 46(11): 1180-1185.
18. Mariappan P, Brown DJ, McNeill AS. Intravesical prostatic protrusion is better than prostate volume in predicting the outcome of trial without catheter in white men presenting with acute urinary retention: a prospective clinical study. J Urol. 2007; 178(2): 573-577; discussion 577.
19. Manieri C, Carter SS, Romano G, Trucchi A, Valenti M, Tubaro. A Diagnosis of bladder outlet obstruction in men by ultrasound measurement of bladder wall thickness. J Urol. 1998; 159(3): 761-765.
20. Blatt AH, Titus J, Chan L. Ultrasound measurement of bladder wall thickness in the assessment of voiding dysfunction. J Urol. 2008; 179: 2275-2278, discussion 2278-2279.
21. Ockrim JL, Laniado ME, Patel A, Tubaro A, St Clair Carter S. A probability based system for combining simple office parameters as a predictor of bladder outlet obstruction. J Urol. 2001; 166: 2221-2225.
22. Yuen JS, Ngiap JT, Cheng CW, Foo KT. Effects of bladder volume on transabdominal ultrasound measurement of intravesical prostatic protrusion and volume. Int J Urol. 2002; 9(4): 2255-2259.
23. Foo KT. Decision making in the management of benign prostatic enlargement and the role of transabdominal ultrasound. Int J Urol. 2010: 17(12): 974-979.