The correlation of intravesical prostatic protrusion with storage symptoms, as measured by transrectal ultrasound

Abstract

Purpose: Intravesical prostatic protrusion (IPP) is a morphological change that's due to excessive growth of the median and lateral lobes of the prostate into the bladder. Few studies have been performed regarding the correlation between IPP and the voiding/storage symptoms. The aim of this study is to identify the clinical significance of IPP by defining its relationship with the prostate volume (PV), the International Prostate Symptom Score (IPSS), the uroflowmetry results and the medication response. Materials and methods: We performed a retrospective study of 95 male patients who were examined between August 2006 and July 2007. The patients were evaluated with the IPSS/quality of life (QoL) test, uroflowmetry (Urodyn-1000™; Medtronic), the post void residual urine (PVR), and IPP and PV by transrectal ultrasound (TRUS) (PROSOUND SSD-3500™; ALOKA). The IPP was compared with the total IPSS, the voiding and storage symptom score, uroflowmetry parameters and the flow patterns (normal, obstructive, detrusor impairment, Valsalva). The patients were classified into two groups (the IPP and non-IPP groups) based on the presence of IPP as identified by TRUS. Results: The PV and IPP showed a significant correlation (r=0.627, p< 0.001). There was no correlation between IPP and total IPSS (p=0.444); however, the storage symptom score was significantly increased in proportion to IPP (p=0.030). With an IPP increase, the Qmax was decreased (r=-0.319, p<0.001) and the PVR was increased (r=0.388, p=0.002). The IPP group showed a lower decrease of the QoL score after 8 weeks of medication, as compared to the non-IPP group (p=0.034). Conclusions: The IPP showed significant correlation with the storage symptoms, but not with the total IPSS. Theoretically, IPP is a unique anatomical configuration of the prostate, and it may worsen the prominent storage symptoms that are the result of irritation of the bladder neck and trigone. IPP should be checked carefully during TRUS as IPP could potentially be a useful marker for the assessment and management of lower urinary tract symptoms.