Histological and quantitative analyzes of the stromal and acinar components of normal human prostate zones

BACKGROUND

McNeal divided the human prostate into three major anatomical areas: the peripheral zone (PZ), the central zone (CZ), and the transition zone (TZ). Each of these areas is biologically and histologically distinct. The PZ and TZ have clinical significance and are associated with prostate cancer (PC) and benign prostatic hyperplasia (BPH), respectively. Therefore, the objective of the present study was to quantitatively and qualitatively analyze the parenchymal and stromal components that constitute the different prostate zones.

METHODS

We assessed 19 samples from each prostate zone. The samples were obtained from necropsies of young people between 18 and 32 years of age with intact urogenital tracts. The samples were fixed in 4% buffered formalin and processed for paraffin embedding. Sections with a thickness of five micrometres were obtained from each sample. The sections were stained using histochemical and immunohistochemical techniques to identify the acinar and stromal components of each zone. Photomicrographs were obtained for morphometric analysis using an algorithm based on color segmentation. Data were analyzed using one-way analysis of variance (ANOVA) with the Bonferroni post-test. Differences with P < 0.05 were regarded as statistically significant.

RESULTS

Collagen fibres were more numerous in the TZ (+40.26%; P = 0.0230) than in the PZ. Muscle fibres were also more numerous in the TZ (+47.05%; P = 0.0120) than in the PZ. Elastic system fibres in the TZ significantly differed from those in the PZ (+84.61%; P = 0.0012) and the CZ (+61.66%; P = 0.0074). Similarly, nerves in the PZ (-42.86%; P = 0.0107) significantly differed from nerves in the CZ. Epithelial height was lower in the TZ than in the PZ (-30.17%; P = 0.0034) and the CZ (-25.01%; P = 0.0330).

CONCLUSION

Our objective, quantitative data regarding the various elements that constitute the normal prostate stroma allowed us to reveal differences among prostate zones. This study established patterns for normal parameters and may be used for posterior comparisons in histopathological analysis.

Effect of hyoscine butylbromide on prostate multiparametric MRI anatomical and functional image quality

AIM

To evaluate the effect of the spasmolytic agent hyoscine butylbromide (HBB) on the quality of anatomical and functional imaging of the prostate.

MATERIALS AND METHODS

One hundred and seventy-three patients were included in this retrospective study. Eighty-seven patients received intravenous HBB prior to scanning (HBB group) and 86 patients did not (non-HBB group). Multiparametric (mp) 3 T magnetic resonance imaging (MRI) was performed using a 32-channel body coil. Two radiologists independently evaluated the image quality of T2-weighted imaging (WI), diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps, using a five-point Likert scale. DWI was further assessed for distortion and artefact (four-point Likert scale), and T2WI for the presence of motion artefact or blurring. Dynamic contrast-enhanced (DCE) image quality was assessed by recording the number of corrupt contrast curve data points.

RESULTS

T2W image quality in the HBB group was significantly higher than in the non-HBB group (3.63±1.11 versus 2.84±0.899); p<0.001. The HBB group also showed significantly less T2W motion and T2W blur than the non-HBB group (23% and 51.7% versus 53.5% and 83.7%, respectively; p<0.001); however, there was no significant improvement in DWI or ADC image quality, or DWI degree of distortion or artefact. There was a trend towards a lower number of corrupted data points from the contrast curve (2.47±2.44 versus 3.68±2.64), but this did not reach significance (p=0.052).

CONCLUSION

Administration of HBB significantly improves the image quality of T2WI images. These results provide evidence for the use of HBB in routine patient preparation prior to prostate mpMRI.

Stereomorphology of the glandular parenchyma of the inferoposterolateral area of human prostate gland

OBJECTIVE

Introduction: The human prostate gland contains numerous tubular masses of different calibers in its parenchyma. They form the tubuloalveolar prostate glandules, constituting from numerous prostatic excretory ductules as well as major excretory ducts. The aim: The study was aimed at 3D visualization of individual microelements of the tubuloalveolar aggregations, localized within the peripheral area.

PATIENTS AND METHODS

Materials and methods: To meet the objectives of the study a series of paraffin plane-parallel 4 μm sections has been obtained in the peripheral prostate area. The serial sections were stained with hematoxylin and eosin. After the analysis of the series of sections, the graphical two-dimensional and plastic 3D reconstructions of the investigated microobjects have been made sequentially in depth.

RESULTS

Results: Presence of the epithelial creases and invaginations of the wall in the luminal contour of tubuloalveolar aggregations of the prostate has been found. Creases can be solitary, multiple, or wavy; they can be localized both symmetrically and asymmetrically, with different heights and thicknesses. Intraluminal invaginations, along with the epithelial crease, contain a stromal muscle component with localized blood loop-shaped microvessel. The creases of the glandular epithelium and intraluminal invaginations can "overlap" the lumens of the tubuloalveolar aggregations up to 2/3 of the width, making the inner lumen sinuous that influences the laminar flow of the liquid.

CONCLUSION

Conclusions: Alternation of the considerable enlargement and narrowing of the inner diameter is common for the tubuloalveolar aggregations which can affect the secreta deposition and movement.

Stereomorphology of the peripheral zone of the human prostate

OBJECTIVE

Introduction: The human prostate gland is a complex organ that consists of two main components - glandular and non-glandular. The first of them represents a compound of components of different origin, structure, location, and complexity of spatial organization. Their stereomorphology and microanatomical interrelations remain understudied for a number of reasons. The aim: The objective of the research was to study the stereomorphological features of the glandular component of the peripheral zone of the prostate in view of its zonal structure concept.

PATIENTS AND METHODS

Materials and methods: The material for the study was the glandular zone of the human prostate, which corresponds to the peripheral zone of the prostate according to the classification (Mc.Neal J.E., 1988). The following methods were used in the study: histological (4 mkm thick paraffin sections), microscopic (light microscopy using the Olympus BX-41 microscope), stereomorphological (obtaining waxed model reconstructions based on graphic ones). The study was conducted on 10 isolated prostate preparations (10 series of 50 preparations in each) taken from the deceased men without changes in the organ under investigation. The prostate gland was fixed in a 10% solution of buffered formalin, followed by obtaining serial plane-parallel sections and staining with hematoxylin and eosin according to the conventional technique.

RESULTS

Results and conclusions: The ducts of the glands of the peripheral zone of the human prostate normally have recurrent luminal dilatations, which, like the multi-cavity terminal portions, can serve as a place for depositing a secret. The ducts of the peripheral zone glands, with the exception of the main duct, visually differ little in diameter. Their walls and walls of intra-acinar cavities are lined with homologous epithelial cells. Therefore, there is no clear morphological boundary between the transfer of the terminal portion to the duct and from one excretory duct to the other.

Measurement and modeling of diffusion time dependence of apparent diffusion coefficient and fractional anisotropy in prostate tissue ex vivo

The purpose of this study was to measure and model the diffusion time dependence of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) derived from conventional prostate diffusion-weighted imaging methods as used in recommended multiparametric MRI protocols. Diffusion tensor imaging (DTI) was performed at 9.4 T with three radical prostatectomy specimens, with diffusion times in the range 10-120 ms and b-values 0-3000 s/mm² . ADC and FA were calculated from DTI measurements at b-values of 800 and 1600 s/mm² . Independently, a two-component model (restricted isotropic plus Gaussian anisotropic) was used to synthesize DTI data, from which ADC and FA were predicted and compared with the measured values. Measured ADC and FA exhibited a diffusion time dependence, which was closely predicted by the two-component model. ADC decreased by about 0.10-0.15 μm² /ms as diffusion time increased from 10 to 120 ms. FA increased with diffusion time at b-values of 800 and 1600 s/mm² but was predicted to be independent of diffusion time at b = 3000 s/mm² . Both ADC and FA exhibited diffusion time dependence that could be modeled as two unmixed water pools - one having isotropic restricted dynamics, and the other unrestricted anisotropic dynamics. These results highlight the importance of considering and reporting diffusion times in conventional ADC and FA calculations and protocol recommendations, and inform the development of improved diffusion methods for prostate cancer imaging.

Neural supply of the male urethral sphincter: comprehensive anatomical review and implications for continence recovery after radical prostatectomy

PURPOSE

To review the anatomical facts of urethral sphincter (US) innervation discovered over the last three decades and to determine the implications for continence recovery after radical prostatectomy (RP).

METHODS

Using the PubMed^® database, we searched for peer-reviewed articles in English between January 1985 and September 2015, with the following terms: 'urethral sphincter,' 'urethral rhabdosphincter,' 'urinary continence and nerve supply' and 'neuroanatomy and nerve sparing.' The anatomical methodology, number of bodies examined, data, figures, relevant facts and text were analyzed.

RESULTS

Seventeen articles on 254 anatomical subjects were reviewed. Coexisting pathways were described in every article. Dissection, histology, simulation or electron microscopy evidence supported arguments for somatic and autonomic pathways. From the most to the least substantiated, somatic sphincteric fibers were described extra- or intrapelvic as: direct from the distal pudendal nerve (PuN), recurrent from the dorsal nerve of the penis, from the proximal PuN with an intrapelvic course, extrapudendal somatic fibers dispersed among autonomic pelvic fibers. From the pelvic plexus, or from the neurovascular bundles, autonomic fibers to the US have been described in 13 of the reviewed articles, with at least each of the available anatomical methods.

CONCLUSION

Because continence depends on a number of factors, it is challenging to delineate the specific impact of periprostatic nerve sparing on continence, but the anatomical data suggest that RP surgeons should steer toward the preservation and protection of these nerves whenever possible.

Understanding Spatially Complex Segmental and Branch Anatomy Using 3D Printing: Liver, Lung, Prostate, Coronary Arteries, and Circle of Willis

RATIONALE AND OBJECTIVES

Three-dimensional (3D) manufacturing is shaping personalized medicine, in which radiologists can play a significant role, be it as consultants to surgeons for surgical planning or by creating powerful visual aids for communicating with patients, physicians, and trainees. This report illustrates the steps in development of custom 3D models that enhance the understanding of complex anatomy.

MATERIALS AND METHODS

We graphically designed 3D meshes or modified imported data from cross-sectional imaging to develop physical models targeted specifically for teaching complex segmental and branch anatomy. The 3D printing itself is easily accessible through online commercial services, and the models are made of polyamide or gypsum.

RESULTS

Anatomic models of the liver, lungs, prostate, coronary arteries, and the Circle of Willis were created. These models have advantages that include customizable detail, relative low cost, full control of design focusing on subsegments, color-coding potential, and the utilization of cross-sectional imaging combined with graphic design.

CONCLUSIONS

Radiologists have an opportunity to serve as leaders in medical education and clinical care with 3D printed models that provide beneficial interaction with patients, clinicians, and trainees across all specialties by proactively taking on the educator's role. Complex models can be developed to show normal anatomy or common pathology for medical educational purposes. There is a need for randomized trials, which radiologists can design, to demonstrate the utility and effectiveness of 3D printed models for teaching simple and complex anatomy, simulating interventions, measuring patient satisfaction, and improving clinical care.

Determining the chemical exchange saturation transfer (CEST) behavior of citrate and spermine under in vivo conditions

PURPOSE

To estimate the exchange rates of labile (1) H in citrate and spermine, metabolites present in prostatic secretions, to predict the size of the citrate and spermine CEST effects in vivo.

METHODS

CEST z-spectra were acquired at high-field [11.7 Tesla (T)] from citrate and spermine solutions at physiological pH (6.5) using saturation power 6 μT. CEST was performed at different temperatures to determine exchange regimes (slow, intermediate or fast). For low pH solutions of spermine, exchange rates were estimated from resonance line width, fitting z-spectra using the Bloch equations incorporating exchange, and using quantifying exchange using saturation time experiments (QUEST). These rates were extrapolated to physiological pH.

RESULTS

Citrate showed little CEST effect at pH 6.5 and temperature (T) = 310 K (maximum 0.001% mM(-1) ), indicating fast exchange, whereas spermine showed greater CEST effects (maximum 0.2% mM(-1) ) indicating intermediate-to-fast exchange. Extrapolating data acquired from low pH spermine solutions predicts exchange rates at pH 6.5 and T of 310 K of at least 2 × 10(4) s(-1) .

CONCLUSION

Citrate and spermine show minimal CEST effects at 11.7T even using high saturation power. These effects would be much less than 2% at clinical field-strengths due to relatively faster exchange and would be masked by CEST from proteins. Magn Reson Med 76:742-746, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Information-based ranking of 10 compartment models of diffusion-weighted signal attenuation in fixed prostate tissue

This study compares the theoretical information content of single- and multi-compartment models of diffusion-weighted signal attenuation in prostate tissue. Diffusion-weighted imaging (DWI) was performed at 9.4 T with multiple diffusion times and an extended range of b values in four whole formalin-fixed prostates. Ten models, including different combinations of isotropic, anisotropic and restricted components, were tested. Models were ranked using the Akaike information criterion. In all four prostates, two-component models, comprising an anisotropic Gaussian component and an isotropic restricted component, ranked highest in the majority of voxels. Single-component models, whether isotropic (apparent diffusion coefficient, ADC) or anisotropic (diffusion tensor imaging, DTI), consistently ranked lower than multi-component models. Model ranking trends were independent of voxel size and maximum b value in the range tested (1.6-16 mm(3) and 3000-10,000 s/mm(2)). This study characterizes the two major water components previously identified by biexponential models and shows that models incorporating both anisotropic and restricted components provide more information-rich descriptions of DWI signals in prostate tissue than single- or multi-component anisotropic models and models that do not account for restricted diffusion.

[New findings of clinical anatomy in pelvis]

Surgical anatomy involves clarifying the mutual relationships of each structure in the operative field. Knowledge of new surgical anatomy has arisen via new methods or approaches. Associated with the development and spread of laparoscopic surgery in recent years, adaptation to changes in surgical techniques using knowledge of classical pelvic anatomy has been difficult. Better knowledge of the delicate structures surrounding the prostate is essential in order to provide both cancer control and functional preservation with regard to radical prostatectomy. In this report, we review the progress in knowledge of pelvic anatomy, particularly regarding the endopelvic fascia, prostatic fascia and Denonvilliers' fascia.

Population-based prediction of subject-specific prostate deformation for MR-to-ultrasound image registration

Statistical shape models of soft-tissue organ motion provide a useful means of imposing physical constraints on the displacements allowed during non-rigid image registration, and can be especially useful when registering sparse and/or noisy image data. In this paper, we describe a method for generating a subject-specific statistical shape model that captures prostate deformation for a new subject given independent population data on organ shape and deformation obtained from magnetic resonance (MR) images and biomechanical modelling of tissue deformation due to transrectal ultrasound (TRUS) probe pressure. The characteristics of the models generated using this method are compared with corresponding models based on training data generated directly from subject-specific biomechanical simulations using a leave-one-out cross validation. The accuracy of registering MR and TRUS images of the prostate using the new prostate models was then estimated and compared with published results obtained in our earlier research. No statistically significant difference was found between the specificity and generalisation ability of prostate shape models generated using the two approaches. Furthermore, no statistically significant difference was found between the landmark-based target registration errors (TREs) following registration using different models, with a median (95th percentile) TRE of 2.40 (6.19) mm versus 2.42 (7.15) mm using models generated with the new method versus a model built directly from patient-specific biomechanical simulation data, respectively (N = 800; 8 patient datasets; 100 registrations per patient). We conclude that the proposed method provides a computationally efficient and clinically practical alternative to existing complex methods for modelling and predicting subject-specific prostate deformation, such as biomechanical simulations, for new subjects. The method may also prove useful for generating shape models for other organs, for example, where only limited shape training data from dynamic imaging is available.

Statistical Biomechanical Surface Registration: Application to MR-TRUS Fusion for Prostate Interventions

A common challenge when performing surface-based registration of images is ensuring that the surfaces accurately represent consistent anatomical boundaries. Image segmentation may be difficult in some regions due to either poor contrast, low slice resolution, or tissue ambiguities. To address this, we present a novel non-rigid surface registration method designed to register two partial surfaces, capable of ignoring regions where the anatomical boundary is unclear. Our probabilistic approach incorporates prior geometric information in the form of a statistical shape model (SSM), and physical knowledge in the form of a finite element model (FEM). We validate results in the context of prostate interventions by registering pre-operative magnetic resonance imaging (MRI) to 3D transrectal ultrasound (TRUS). We show that both the geometric and physical priors significantly decrease net target registration error (TRE), leading to TREs of 2.35 ± 0.81 mm and 2.81 ± 0.66 mm when applied to full and partial surfaces, respectively. We investigate robustness in response to errors in segmentation, varying levels of missing data, and adjusting the tunable parameters. Results demonstrate that the proposed surface registration method is an efficient, robust, and effective solution for fusing data from multiple modalities.

Prostate contours delineation using interactive directional active contours model and parametric shape prior model

Prostate contours delineation on Magnetic Resonance (MR) images is a challenging and important task in medical imaging with applications of guiding biopsy, surgery and therapy. While a fully automated method is highly desired for this application, it can be a very difficult task due to the structure and surrounding tissues of the prostate gland. Traditional active contours-based delineation algorithms are typically quite successful for piecewise constant images. Nevertheless, when MR images have diffuse edges or multiple similar objects (e.g. bladder close to prostate) within close proximity, such approaches have proven to be unsuccessful. In order to mitigate these problems, we proposed a new framework for bi-stage contours delineation algorithm based on directional active contours (DAC) incorporating prior knowledge of the prostate shape. We first explicitly addressed the prostate contour delineation problem based on fast globally DAC that incorporates both statistical and parametric shape prior model. In doing so, we were able to exploit the global aspects of contour delineation problem by incorporating a user feedback in contours delineation process where it is shown that only a small amount of user input can sometimes resolve ambiguous scenarios raised by DAC. In addition, once the prostate contours have been delineated, a cost functional is designed to incorporate both user feedback interaction and the parametric shape prior model. Using data from publicly available prostate MR datasets, which includes several challenging clinical datasets, we highlighted the effectiveness and the capability of the proposed algorithm. Besides, the algorithm has been compared with several state-of-the-art methods.

Investigation of factors affecting hypothermic pelvic tissue cooling using bio-heat simulation based on MRI-segmented anatomic models

This study applied a simulation method to map the temperature distribution based on magnetic resonance imaging (MRI) of individual patients, and investigated the influence of different pelvic tissue types as well as the choice of thermal property parameters on the efficiency of endorectal cooling balloon (ECB). MR images of four subjects with different prostate sizes and pelvic tissue compositions, including fatty tissue and venous plexus, were analyzed. The MR images acquired using endorectal coil provided a realistic geometry of deformed prostate that resembled the anatomy in the presence of ECB. A single slice with the largest two-dimensional (2D) cross-sectional area of the prostate gland was selected for analysis. The rectal wall, prostate gland, peri-rectal fatty tissue, peri-prostatic fatty tissue, peri-prostatic venous plexus, and urinary bladder were manually segmented. Pennes' bioheat thermal model was used to simulate the temperature distribution dynamics, by using an in-house finite element mesh based solver written in MATLAB. The results showed that prostate size and periprostatic venous plexus were two major factors affecting ECB cooling efficiency. For cases with negligible amount of venous plexus and small prostate, the average temperature in the prostate and neurovascular bundles could be cooled down to 25 °C within 30 min. For cases with abundant venous plexus and large prostate, the temperature could not reach 25 °C at the end of 3 h cooling. Large prostate made the cooling difficult to propagate through. The impact of fatty tissue on cooling effect was small. The filling of bladder with warm urine during the ECB cooling procedure did not affect the temperature in the prostate or NVB. In addition to the 2D simulation, in one case a 3D pelvic model was constructed for volumetric simulation. It was found that the 2D slice with the largest cross-sectional area of prostate had the most abundant venous plexus, and was the most difficult slice to cool, thus it may provide a conservative prediction of the cooling effect. This feasibility study demonstrated that the simulation tool could potentially be used for adjusting the setting of ECB for individual patients during hypothermic radical prostatectomy. Further studies using MR thermometry are required to validate the in silico results obtained using simulation.

Establishment of Reference Ranges for Prostate Volume and Annual Prostate Volume Change Rate in Korean Adult Men: Analyses of a Nationwide Screening Population

We aimed to determine normal reference ranges for prostate volume (PV) and annual PV change rate in a Korean nationwide screening population. Data from men who underwent a routine health check-up were collected from 13 university hospitals. The cohort comprised men aged ≥40 yr who had undergone 2 or more serial transrectal ultrasonographies. Men with initial PV>100 mL; serum PSA level>10 ng/mL; PV reduction>20% compared with initial PV, or who had history of prostate cancer or prostate surgery, were excluded. Linear regression and mixed effects regression analyses were used to predict mean PV and longitudinal change in PV over time. A total of 2,967 men formed the study cohort. Age, body mass index (BMI), and serum prostate-specific antigen (PSA) level were found to be significant predictors of PV. A predicted PV table, with a 95% confidence interval (CIs), was developed after adjusting for these 3 variables. Annual PV change rate was 0.51 mL/year (95% CI, 0.47-0.55). Annual PV change rate according to age was 0.68 mL/year, 0.84 mL/year, 1.09 mL/year, and 0.50 mL/year for subjects in their 40s, 50s, 60s, and ≥70 yr, respectively. Predicted annual PV change rate differed depending on age, BMI, serum PSA level and baseline PV. From a nationwide screening database, we established age-, PSA-, and BMI-specific reference ranges for PV and annual PV change rate in Korean men. Our newly established reference ranges for PV and annual PV change rate will be valuable in interpreting PV data in Korean men.

Pelvic Arterial Anatomy Relevant to Prostatic Artery Embolisation and Proposal for Angiographic Classification

PURPOSE

To describe and categorize the angiographic findings regarding prostatic vascularization, propose an anatomic classification, and discuss its implications for the PAE procedure.

METHODS

Angiographic findings from 143 PAE procedures were reviewed retrospectively, and the origin of the inferior vesical artery (IVA) was classified into five subtypes as follows: type I: IVA originating from the anterior division of the internal iliac artery (IIA), from a common trunk with the superior vesical artery (SVA); type II: IVA originating from the anterior division of the IIA, inferior to the SVA origin; type III: IVA originating from the obturator artery; type IV: IVA originating from the internal pudendal artery; and type V: less common origins of the IVA. Incidences were calculated by percentage.

RESULTS

Two hundred eighty-six pelvic sides (n = 286) were analyzed, and 267 (93.3%) were classified into I-IV types. Among them, the most common origin was type IV (n = 89, 31.1%), followed by type I (n = 82, 28.7%), type III (n = 54, 18.9%), and type II (n = 42, 14.7%). Type V anatomy was seen in 16 cases (5.6%). Double vascularization, defined as two independent prostatic branches in one pelvic side, was seen in 23 cases (8.0%).

CONCLUSIONS

Despite the large number of possible anatomical variations of male pelvis, four main patterns corresponded to almost 95% of the cases. Evaluation of anatomy in a systematic fashion, following a standard classification, will make PAE a faster, safer, and more effective procedure.

Assessment of non-Gaussian diffusion with singly and doubly stretched biexponential models of diffusion-weighted MRI (DWI) signal attenuation in prostate tissue

Non-Gaussian diffusion dynamics was investigated in the two distinct water populations identified by a biexponential model of diffusion in prostate tissue. Diffusion-weighted MRI (DWI) signal attenuation was measured ex vivo in two formalin-fixed prostates at 9.4 T with diffusion times Δ = 10, 20 and 40 ms, and b values in the range 0.017-8.2 ms/µm(2) . A conventional biexponential model was compared with models in which either the lower diffusivity component or both of the components of the biexponential were stretched. Models were compared using Akaike's Information Criterion (AIC) and a leave-one-out (LOO) test of model prediction accuracy. The doubly stretched (SS) model had the highest LOO prediction accuracy and lowest AIC (highest information content) in the majority of voxels at Δ = 10 and 20 ms. The lower diffusivity stretching factor (α2 ) of the SS model was consistently lower (range ~0.3-0.9) than the higher diffusivity stretching factor (α1 , range ~0.7-1.1), indicating a high degree of diffusion heterogeneity in the lower diffusivity environment, and nearly Gaussian diffusion in the higher diffusivity environment. Stretched biexponential models demonstrate that, in prostate tissue, the two distinct water populations identified by the simple biexponential model individually exhibit non-Gaussian diffusion dynamics.

Efficacy of 5α-reductase inhibitors for patients with large benign prostatic hyperplasia (>80 mL) after transurethral resection of the prostate

PURPOSE

To prospectively evaluate 5α-reductase inhibitors (5αRIs) for benign prostatic hyperplasia (BPH) patients with a large prostate (>80 mL) after transurethral resection of the prostate (TURP).

MATERIALS AND METHODS

Eighty-seven patients were recruited from January 2007 to October 2014. Patients were randomized into a trial and a control group. The trial group was treated with 5αRIs for 3 years after TURP, while the control group received a placebo. We evaluated the indicators before, peri and after TURP.

RESULTS

There were no significant differences in the indicators before and peri-TURP. Six months later, there were significant differences in PSA and hematuria (HU). Three years after TURP, there were significant differences in prostate volume (PV), level of prostate-specific antigen (PSA), the maximum flow rate (Qm), and HU between the trial and control groups. Additionally, there were significant differences in the PV, PSA, international prostate symptom score (IPSS), patient quality of life (QoL) in the trial group alone between those treated with finasteride and those treated with dutasteride.

CONCLUSIONS

After TURP for large BPH, administration of 5αRIs for 3 years improved PV, PSA, Qm and HU. Additionally, dutasteride produced superior improvements in PV, PSA, IPSS and QoL compared with finasteride.

In vivo visualization of prostate brachytherapy seeds with photoacoustic imaging

We conducted a canine study to investigate the in vivo feasibility of photoacoustic imaging for intraoperative updates to brachytherapy treatment plans. A fiber coupled to a 1064-nm Nd:YAG laser was inserted into high-dose-rate brachytherapy needles, which diffused light spherically. These needles were inserted through the perineum into the prostate for interstitial light delivery and the resulting acoustic waves were detected with a transrectal ultrasound probe. Postoperative computed tomography images and ex vivo photoacoustic images confirmed seed locations. Limitations with insufficient light delivery were mitigated with short-lag spatial coherence (SLSC) beamforming, providing a 10-20 dB contrast improvement over delay-and-sum (DAS) beamforming for pulse energies ranging from 6.8 to 10.5 mJ with a fiber-seed distance as large as 9.5 mm. For the same distance and the same range of energy densities, signal-to-noise ratios (SNRs) were similar while the contrast-to-noise ratio (CNR) was higher in SLSC compared to DAS images. Challenges included visualization of signals associated with the interstitial fiber tip and acoustic reverberations between seeds separated by ≤ 2 mm. Results provide insights into the potential for clinical translation to humans.

Mesterolone treatment of aging male syndrome improves lower urinary tract symptoms

OBJECTIVE

To investigate the effects of mesterolone on prostate in patients treated for aging male syndrome.

METHODS

The cross-sectional study was conducted from June to September, 2009, at endocrinology and metabolism department of Yuzuncu Yil University, Van, Turkey, andcomprised patients with symptoms of aging male syndrome and/or low testosterone. They were given mesterolone 50 mg/day per oral for two months. Aging Male Symptoms and International Prostate Symptom Score questionaires and prostate-related quality of life scores were completed and prostate ultrasonography (USG) was performed before and after the treatment. Total testosterone, free testosterone, gonadotropins, estradiol, prolactin, sex-hormone binding globulin, as well as total and free prostate-specific antigen were also studied.

RESULTS

Of the 34 patients in the study, 22(64.70%) had their prostate volume increased, while 12(35.29%) had it decreased. The change, however, was not statistically significant (p<0.098). Mesterolone significantly improved Aging Male Symptoms, International Prostate Symptom and prostate-related quality of life scores (p<0.001). These improvements though significant were independent of the changes in prostate volume. Total testosterone, sex-hormone binding globulin andestradiol decreased, while free testosterone showed no change (p<0.002, p<0.001, p<0.024, p<0.337). The fraction of free testosterone increased (p<0.001), while total and free prostate-specific antigen did not change (p<0.368 and p<0.841) CONCLUSION: Mesterolone proved to be a safe alternative in the treatment of Aging Male Syndrome. It also improved lower urinary tract symptoms and prostate-related quality of life.

Prostate volume and urinary discomforts in elderly

Occasional doubts about the real effect of the prostate volume on the urinary discomforts that elderly have been experiencing required additional assessment of these parameters. The aim of this study was to re-evaluate relationship between the urinary discomforts of the elderly and the prostate volume in comparison with age. Results of the group of 79 patients observed within one-year period were analyzed. In assessing their urinary discomforts the International Prostate Symptom Score (IPSS) was calculated, the ultrasound prostate volumetry was performed, and both of these parameters where compared with age. Statistical analysis of the results confirmed significant positive correlation between the prostate volume and age, positive correlation between IPSS and age, as well as between prostate volume and IPSS.

Multiphoton gradient index endoscopy for evaluation of diseased human prostatic tissue ex vivo

Multiphoton microscopy can instantly visualize cellular details in unstained tissues. Multiphoton probes with clinical potential have been developed. This study evaluates the suitability of multiphoton gradient index (GRIN) endoscopy as a diagnostic tool for prostatic tissue. A portable and compact multiphoton endoscope based on a 1-mm diameter, 8-cm length GRIN lens system probe was used. Fresh ex vivo samples were obtained from 14 radical prostatectomy patients and benign and malignant areas were imaged and correlated with subsequent H&E sections. Multiphoton GRIN endoscopy images of unfixed and unprocessed prostate tissue at a subcellular resolution are presented. We note several differences and identifying features of benign versus low-grade versus high-grade tumors and are able to identify periprostatic tissues such as adipocytes, periprostatic nerves, and blood vessels. Multiphoton GRIN endoscopy can be used to identify both benign and malignant lesions in ex vivo human prostate tissue and may be a valuable diagnostic tool for real-time visualization of suspicious areas of the prostate.