Sonographic Correlations between Intravesical Prostatic Protrusion and Bladder Outlet Obstruction in Patients with Symptomatic Benign Prostatic Hyperplasia in Ibadan, Nigeria




Background: Evaluating bladder outlet obstruction (BOO) in patients with prostatic enlargement may reflect the severity of the disease and aid in predicting the treatment outcome.

Objectives: To determine the sonological correlation between intravesical prostatic protrusion and bladder outlet obstruction in patients with symptomatic benign prostatic enlargement.

Methods: This prospective study was conducted over one year at the Department of Radiology, University College Hospital, Ibadan. A transabdominal ultrasound scan of the urinary bladder and prostate gland was carried out on patients with prostatic enlargement and BOO. The intravesical prostatic protrusion, pre-and post-void urine volumes, prostate volume and bladder wall thickness were measured.

Results: A total of 132 men aged 43 to 90 years (mean age: 63.8±8.64 years) were studied. The median size of the intravesical prostatic protrusion (IPP) was 7.25 mm (IQR: 0.00 mm; 14.9 mm). The mean prostate volume was 63.3ml±36.0ml. Most subjects (55; 41.7%) had a prostate volume above 60ml, and most patients (101, 77.2%) had bladder wall thickness less than 5mm. The mean bladder wall thickness was 4.26mm±1.54mm. There was a statistically significant correlation between IPP and pre-void urine volume and prostate volume (p = 0.002 and <0.001, respectively). Patients over 70 years had increasing IPP and post-void urine, which lacked statistical significance (p = 0.15).

Conclusion: The severity of bladder outlet obstruction was reflected in the pre-void urine volume, which correlated with the size of IPP.


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Original Research