Intravesical Prostate Protrusion (IPP) versus Middle Lobe Volume on Ultrasonography in Assessing the Impact of Benign Prostatic Hyperplasia

Background: Ultrasound is the main method of exploring the prostate. In benign prostatic hyperplasia (BPH), it provides important morphological information and assesses its impact, helping to guide the treatment. Objective: To compare intravesical prostatic protrusion (IPP) and middle lobe volume by ultrasound in BPH. Method: This was a single center prospective, descriptive and analytical study, over a period of 6 months, including 95 patients, undergoing prostatic trans-abdominal ultrasound. Patients were selected by a single urologist for clinical suspicion of benign prostatic hypertrophy. The ultrasound examination was done by a single senior radiologist. Results: The mean age of the patients was 66.63 ± 11.55 years with ranges from 38 to 98 years. The prevalence of BPH was 76.84%. The rate of patient with middle lobe protrusion was 48.42%. The mean middle lobe volume was 11.29 ± 12.90 ml. More than half of the patients (50.91%) had an IPP stage 3 of. The mean bladder wall thickness was 6.08 ± 2.58 mm, with 50.53% being pathological. The post-voiding residue (PVR) was significant in 38.75% of patients. Renal repercussions were present in 17.89%. The correlation analysis did not note a statistical link between prostate volume and quality of life score (p > 0.05). There was a statistically significant correlation between IPP values and quality of life score (p = 00461), IPSS score (p = 0.0424) and PVR (p = 0.0395). For middle lobe volume, there was a correlation with PVR (p = 0.0018). There was no correlation with clinical impact (quality of life score and IPSS score). Conclusion: The IPP appears to be an easy element to measure and better How to cite this paper: Tchaou, M., Hounkpevi, J.M., Gbande, P., Padja, E., Kpatcha, T., Gbadoe, E., Darre, T. and Agoda-Koussema, L.K. (2020) Intravesical Prostate Protrusion (IPP) versus Middle Lobe Volume on Ultrasonography in Assessing the Impact of Benign Prostatic Hyperplasia. Open Journal of Radiology, 10, 193-202. https://doi.org/10.4236/ojrad.2020.104019 Received: October 20, 2020 Accepted: December 1, 2020 Published: December 4, 2020 Copyright © 2020 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access


Introduction
Benign prostatic hyperplasia (BPH) is the most common prostate disease. Its frequency increases with age [1]. Clinical BPH is a highly prevalent disease. By the age of 60 years, nearly 60% had some degree of clinical BPH [2]. Ultrasound is the main method of exploring the prostate because of its accessibility, its simplicity, non-invasive nature and its excellent cost-effectiveness. Its purpose is to provide morphological information on the prostate and to assess the importance of any impact on the upper urinary tract and to help in the selection of patients to determine the type of treatment according to the weight of the prostate, the importance of post-voiding residue (PVR) and the tissue composition of BPH [3].
The evaluation of the volume of the middle lobe or the measurement of intravesical prostatic protrusion (IPP) participates in the assessment of the impact of BPH. Many studies have shown that ultrasonography by assessing IPP can be used to assess the repercussion of BPH on the urinary tract and on the quality of life (QoL) [4] [5]. But in practice, it is rather the volume of the middle lobe that is assessed. The aim of this study was to compare the correlations with clinical and ultrasound effects of IPP and the volume of the middle lobe on ultrasound in BPH.

Material and Method
This was a prospective, descriptive and analytical study, over a period of 6 months, at the Sylvanus Olympio teaching hospital of Lomé, TOGO. The study concerned the trans-abdominal ultrasonography (TAUS) of IPP and middle lobe volume in a consecutive series of patients clinically suspected of having BPH.
Ninety-five patients were included in the study. They were selected by an urologist for clinical suspicion. Those with neurological history, confirmed prostate cancer, lower urinary tract surgery, and urinary catheter or with a parietal or intraluminal bladder lesion were excluded. Ultrasound examinations of the prostate were carried out by a single radiologist, using a 3.5 MHz convex probe.
The variables studied were: age, International Score of Prostatic Symptoms (IPSS), QoLscore, ultrasound findings (prostate volume, middle lobe volume, IPP measurement ( Figure 1), bladder wall thickness, PVR volume, and dilation of renal excretory cavities). The prostate volume was considered normal when it was less than 30 ml, the bladder wall was normal if its thickness was less than 2 mm and the PVR considered significant if greater than 50 ml.

Epidemiological and Clinical Data
The mean age of the patients was 66.63 ± 11.55 years with ranges from 38 to 98 years.

Trans-Abdominal Ultrasonography (TAUS) Data
On TAUS, 73 (76.84%) patients had an enlargement of the prostate, greater than 30 ml. A middle lobe was noted in 55 patients, achieving a prevalence of 57.89% in patient with clinical suspicion of BPH. The mean middle lobe volume was 11.29 ± 12.90 ml (range 1 -64 ml).
An impact on the upper urinary tract, consisting of dilation of the intra-renal excretory cavities, was noted in 17.89%. Open Journal of Radiology

Analysis of Correlations
There is no association between prostate volume and quality of life score (p > 0.05) ( Table 2).
The analysis of the correlations between IPP and clinical and ultrasound variables summarized in Table 3 shows that there is a statistically significant correlation between the values of the IPP and QoL score (p = 00461), the IPSS score

Epidemiological and Clinical Data
Age is a known risk factor of occurrence of BPH, in fact, BPH or prostatic ade- The QoL assessment due to urinary symptoms is subjective and depends heavily on the beliefs and social representation of each patient. The proportion of patients who felt "terrible" was 29.47%. Those who estimated their QoL as "mixed", "mostly dissatisfied" and "unhappy" was 83.16% while it was 54% in the series by Chia et al. in Singapore [11].

Ultrasonography Data
The recommendations of the various professional associations for the practice of additional examinations for BPH are variable. It depends on whether they are oriented towards urologists or general practitioners; whether they take into account the specific habits of each country or are intended to be international.
Sometimes, such is low income countries, imaging exams of BPH are limited ultrasonography. It makes it possible to search for several elements allowing an objective evaluation of the impact of BPH, in order to guide the therapeutic de-Open Journal of Radiology cision. It also provides the elements of disease surveillance. These elements are the prostate volume, middle lobe, bladder wall thickness, PVR and upper urinary tract impact. As for the middle lobe, we can measure its volume or measure its protrusion in the bladder, called intra-vesical prostatic protrusion (IPP). Intravesical prostatic protrusion (IPP) is defined as the protrusion of the middle lobe and/or lateral lobes of the prostate into the lumen of the bladder [12]. It is at the origin of a valve effect deforming the funnel-shaped disposition of the bladder neck, which can be the source of an obstructive symptomatology. This measurement evaluates the distance between the apex of the middle lobe and the neck of the bladder, in the mid sagittal plane, with a bladder filling between 150 and 250 cc. Grade I protrusion is 0 -4.9 mm, grade II 5 -10 mm, and grade III greater than 10 mm [11] [13] [14] [15]. IPP was measurable in 55 patients (57.89%). The mean of the 55 IPP measurements was 14.85 ± 9.10 mm. This mean value is slightly higher than the values found by Aganovic et al. [10] in Bosnia, with 11.7 ± 6.6 mm and by Agbo A.C. et al. [4] in Nigeria, with 12.9 ± 7 mm. As in the series of Eze B.U. et al. [5], who had found 59.4% IPP > 10mm, they were 50.91% classified as grade III in our study.

Correlation Analysis
Statistical analysis notes the existence of a linear relationship between the IPP measurements and the increase in prostate volume (p = 0.0126). Indeed, more the volume of the prostate increases, more the IPP becomes marked. Agbo A.C. et al. [4] in Nigeria (p = 0.002), Franco G et al. [8] in Italy (p = 0.01) also found a significant link between IPP and prostate volume.  [5]. This association is also observed for the IPSS score, whereas it does not exist with the volume of the middle lobe. It is only with PVR that the association is observed with both IPP and middle lobe volume.
These observations lead us to affirm that the measurement of IPP is the best variable in the assessment of the clinical and ultrasound impact of BPH. Lebdai S. et al. [12], affirmed that IPP was a better prognostic factor for upper urinary tract obstruction than prostatic volume. An additional argument in favor of IPP is the ease and speed of its measurement compared to the calculation of the vo-

Conclusion
Intravesical prostatic protrusion (IPP) appears to be an element that is easy to measure and better than the volume of the prostate and the middle lobe in assessing the impact on the quality of life and the quality of urination in patients with benign prostatic hyperplasia.