Login to Access Video or Poster Abstract: MP17-11
Sources of Funding: VA Merit Award: 1010 BX003454-01

Introduction

It has been proposed that prostatic fibrosis contributes to bladder outlet obstruction in men with BPH/LUTS. We used preoperative urodynamics and CT imaging to evaluate the contributions of prostatic enlargement and fibrosis to obstruction in a cohort of men who underwent surgery for BPH/LUTS. Prostate volume and radiodensity were determined from the preoperative CT scan. Hounsfield units (HU), a quantitative measure of radiodensity on CT scans used frequently as a surrogate marker for liver and lung fibrosis, was used as a surrogate marker for prostate fibrosis.

Methods

We identified 34 men (mean age of 66 yrs, range 48-93 yrs) with complete pre-operative urodynamic evaluation for whom non-contrast axial pelvic CT scan images were available. Prostate volume was calculated using the formula for ellipsoid volume (L x W x H x 0.52). Mean prostate HU was determined by averaging the HU of ellipsoid selections of the proximal, middle, and distal prostate. The bladder outlet obstructive index (BOOI) was calculated from the formula P_detQ_max - 2Q_max and used to classify patients as obstructed (BOOI ≥ 40), equivocal (BOOI 20-40), or unobstructed (BOOI < 20). Ten men aged 20-40 years who underwent non-contrast axial CT scanning for flank pain were used as controls.

Results

Mean BOOI was 56 (22 obstructed, 7 equivocal and 5 unobstructed). Mean prostate volume was significantly greater in patients with BPH/LUTS (mean 62 cc; range 19-217 cc) than in controls (mean 24 cc; range 14-33 cc) (<0.0001). _x000D_ Linear regression analysis revealed a significant positive relationship between volume and BOOI (p-value = 0.04) in patients with BPH/LUTS. Mean prostate HU was significantly higher in men with BPH/LUTS (mean 37 HU, standard deviation 6 HU, range 28-49 HU) compared to controls (mean 41 HU, standard deviation 5 HU, range 35-51 HU) (p=0.04) but linear regression analysis revealed no significant positive relationship between HU and BOOI (p = 0.32)._x000D_

Conclusions

Our studies affirm that prostate volume is significantly associated with urodynamic evidence of obstruction among men with BPH/LUTS. Prostatic radiodensity was significantly higher in men with BPH/LUTS compared to young healthy controls, but we found no significant association bettween prostate radiodensity and urodynamic evidence of obstruction in men with BPH/LUTS.

Funding

VA Merit Award: 1010 BX003454-01