Zonal Anatomy Research Articles

Anatomy of the Prostate Gland: Modalities and Techniques for Its Assessment

AbstractProstate imaging is indispensable for the diagnosis and management of prostatic carcinoma and other prostate lesions. Understanding imaging anatomy is the basis for accurate diagnosis and standardized reporting of the prostatic lesions. In this article, we will discuss about general anatomy of the prostate, zonal anatomy, imaging techniques for its assessment, modality specific appearance of different zones of the prostate in detail.

Assessment of quantitative zonal parameters of prostate gland in discrimination of normal, benign, and malignant conditions: are these the more reliable parameters in the diagnosis of prostate cancer?

Prostate cancer diagnosis and treatment are increasing in current public healthcare programs. An improved resolution multiparametric magnetic resonance imaging (MRI) has shown the potential to enhance the detection and differentiation of this medical condition. In this study, MR perfusion parameters were investigated in different ages and diseases to differentiate clinically significant prostate cancer. From January 2017 to December 2022, 72 consecutive patients, who had undergone multiparametric MR imaging were enrolled in this study. Four different patient groups were formed: (1) those with prostate cancer, (2) those with prostatitis, (3) those with benign prostate hyperplasia (BPH), and (4) a control group. Quantitative dynamic contrast-enhanced (DCE)-MRI pharmacokinetic parameters included Ktrans, Kep, Ve, and iAUG. Different measurements were obtained from both the peripheral and transitional zones (PZ and TZ, respectively). Means values were compared between groups based on a univariate analysis. Ktrans and Kep values in the PZ were found to be statistically significantly lower in the control group (p = 0. 003 and p = 0. 011, respectively). It was seen that Ktrans and Ve measurements obtained from PZ had a statistically significant determinant in detecting malignancy (p = 0. 013 and p = 0. 036, respectively). It was seen that Ktrans, Ve, and iAUG obtained from the TZ showed a statistically significant difference in prostate cancer (p = 0.025, p = 0.005, and p = 0. 011, respectively) in contrast to other cases. Peripheral Ve values were statistically significantly lower than those measured Ve values from the TZ in prostate cancer cases (p = 0.002) in contrast to the other cases. Quantitative DCE-MRI parameters may vary according to age, disease, and zonal anatomy. These differences may contribute to the diagnosis of clinically relevant prostate cancer.

Combined ARFI and Shear Wave Imaging of Prostate Cancer: Optimizing Beam Sequences and Parameter Reconstruction Approaches.

This study demonstrates the implementation of a shear wave reconstruction algorithm that enables concurrent acoustic radiation force impulse (ARFI) imaging and shear wave elasticity imaging (SWEI) of prostate cancer and zonal anatomy. The combined ARFI/SWEI sequence uses closely spaced push beams across the lateral field of view and simultaneously tracks both on-axis (within the region of excitation) and off-axis (laterally offset from the excitation) after each push beam. Using a large number of push beams across the lateral field of view enables the collection of higher signal-to-noise ratio (SNR) shear wave data to reconstruct the SWEI volume than is typically acquired. The shear wave arrival times were determined with cross-correlation of shear wave velocity signals in two dimensions after 3-D directional filtering to remove reflection artifacts. To combine data from serially interrogated lateral push locations, arrival times from different pushes were aligned by estimating the shear wave propagation time between push locations. Shear wave data acquired in an elasticity lesion phantom and reconstructed using this algorithm demonstrate benefits to contrast-to-noise ratio (CNR) with increased push beam density and 3-D directional filtering. Increasing the push beam spacing from 0.3 to 11.6 mm (typical for commercial SWEI systems) resulted in a 53% decrease in CNR. In human in vivo data, this imaging approach enabled high CNR (1.61-1.86) imaging of histologically-confirmed prostate cancer. The in vivo images had improved spatial resolution and CNR and fewer reflection artifacts as a result of the high push beam density, the high shear wave SNR, the use of multidimensional directional filtering, and the combination of shear wave data from different push beams.

MRI of Benign Prostatic Hyperplasia: Important Pre- and Posttherapeutic Considerations

New minimally invasive techniques that reduce morbidity while improving lower urinary tract symptoms (LUTS) due to benign prostatic hypertrophy (BPH) have become attractive alternatives for patients, in comparison to traditional techniques such as transurethral resection of the prostate (TURP) and simple prostatectomy. Pre- and postprocedural MRI is not routinely performed for LUTS due to BPH treatments. However, because of the combination of rapidly evolving treatments available for LUTS due to BPH and increasing demand for prebiopsy prostate MRI for detection of clinically significant prostate cancer (PCa), an understanding of procedural techniques and expected changes are important for accurate interpretation of prostate MRI performed after treatment of BPH. The authors discuss the imaging evaluation of LUTS due to BPH and emerging predictors of treatment success. The posttreatment appearance and underlying anatomic changes in the prostate after medical, surgical, and minimally invasive treatments including TURP, simple prostatectomy, laser enucleations and ablations, prostatic urethral lift, water vapor thermal therapy, and prostate artery embolization are detailed. Most procedures reduce prostate volume, notably in the periurethral prostatic tissue. Ablations create areas of necrosis and can distort the normal zonal anatomy between the transition zone and the peripheral zone, and prostate artery embolization creates infarcts in the transition zone. Mechanical prostatic urethral lift devices open the anterior channel at the bladder base but create susceptibility artifacts that can obscure and prevent detection of a lesion in the transition zone. Also discussed are the detection of clinically significant prostate cancer in the postprocedural prostate and imaging of BPH procedure complications such as urethral strictures, abscesses, and hematuria. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material. See the invited commentary by Purysko in this issue.

Automatic segmentation of prostate zonal anatomy on MRI: a systematic review of the literature

ObjectivesAccurate zonal segmentation of prostate boundaries on MRI is a critical prerequisite for automated prostate cancer detection based on PI-RADS. Many articles have been published describing deep learning methods offering great promise for fast and accurate segmentation of prostate zonal anatomy. The objective of this review was to provide a detailed analysis and comparison of applicability and efficiency of the published methods for automatic segmentation of prostate zonal anatomy by systematically reviewing the current literature.MethodsA Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) was conducted until June 30, 2021, using PubMed, ScienceDirect, Web of Science and EMBase databases. Risk of bias and applicability based on Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) criteria adjusted with Checklist for Artificial Intelligence in Medical Imaging (CLAIM) were assessed.ResultsA total of 458 articles were identified, and 33 were included and reviewed. Only 2 articles had a low risk of bias for all four QUADAS-2 domains. In the remaining, insufficient details about database constitution and segmentation protocol provided sources of bias (inclusion criteria, MRI acquisition, ground truth). Eighteen different types of terminology for prostate zone segmentation were found, while 4 anatomic zones are described on MRI. Only 2 authors used a blinded reading, and 4 assessed inter-observer variability.ConclusionsOur review identified numerous methodological flaws and underlined biases precluding us from performing quantitative analysis for this review. This implies low robustness and low applicability in clinical practice of the evaluated methods. Actually, there is not yet consensus on quality criteria for database constitution and zonal segmentation methodology.

The use of 3D digital anatomy model improves the communication with patients presenting with prostate disease: The first experience in Senegal.

We hypothesized that the use of an interactive 3D digital anatomy model can improve the quality of communication with patients about prostate disease. A 3D digital anatomy model of the prostate was created from an MRI scan, according to McNeal's zonal anatomy classification. During urological consultation, the physician presented the digital model on a computer and used it to explain the disease and available management options. The experience of patients and physicians was recorded in questionnaires. The main findings were as follows: 308 patients and 47 physicians participated in the study. In the patient group, 96.8% reported an improved level of understanding of prostate disease and 90.6% reported an improved ability to ask questions during consultation. Among the physicians, 91.5% reported improved communication skills and 100% reported an improved ability to obtain patient consent for subsequent treatment. At the same time, 76.6% of physicians noted that using the computer model lengthened the consultation. This exploratory study found that the use of a 3D digital anatomy model in urology consultations was received overwhelmingly favorably by both patients and physicians, and it was perceived to improve the quality of communication between patient and physician. A randomized study is needed to confirm the preliminary findings and further quantify the improvements in the quality of patient-physician communication.

Morphometric Analysis of Prostate Zonal Anatomy After Transurethral Resection of Prostate and Holmium Laser Enucleation of Prostate Using Magnetic Resonance Imaging: A Pilot Study.

The primary purpose was to compare the completeness of adenomectomy and zonal anatomy of prostate on magnetic resonance imaging prostate after transurethral resection of prostate and Holmium enucleation of prostate. The secondary purpose was to investigate the relationship between preoperative total prostate volume and postoperative transition zone and peripheral zone volume after both procedures. A retrospective review of all patients who underwent transurethral resection of pros- tate or Holmium enucleation of prostate over 3 years (2017-2020) and had at least 1 postoperative magnetic resonance imaging prostate was performed. Volume estimations of the prostate and individual zones were per- formed, and statistical comparisons were made to evaluate morphometric changes between the 2 procedures. A total of 9 patients (mean age, 71.8 years) underwent transurethral resection of prostate and 12 patients (mean age, 66.9 years) underwent Holmium enucleation of prostate. The median pre-operative prostate volume in the Holmium enucleation of prostate group was higher than the transurethral resection of prostate group (101.5 g vs. 62 g; P =.102). However, there was a significant difference in the resected tissue weight favoring Holmium enucleation of prostate over transurethral resection of prostate (P value=.004). The postoperative transition zone and peripheral zone volume as calculated by magnetic resonance imaging remained relatively constant in both procedures. The peripheral zone volume on postoperative magnetic res- onance imaging was found to be independent of transition zone volume even for very large-sized prostates. A well-performed transurethral resection of prostate or Holmium enucleation of prostate cannearly completely eliminate the transition zone volume, irrespective of the size of the prostate as confirmed by magnetic resonance imaging prostate. Additionally, the peripheral zone volume is consistent across the entire spectrum of the prostate size.

MRI-GUIDED RADIOTHERAPY FOR PROSTATE CANCER: A NEW PARADIGM.

Radiotherapy is one of the key treatment modalities for primary prostate cancer. During the last decade, significant advances were made in radiotherapy technology leading to increasing both physical and biological precision. Being a loco-regional treatment approach, radiotherapy requires accurate target dose deposition while sparing surrounding healthy tissue. Conventional radiotherapy is based on computerized tomography (CT) images both for radiotherapy planning and image-guidance, however, shortcomings of CT as soft tissue imaging tool are well known. Nowadays, our ability to further escalate radiotherapy dose using hypofractionation is limited by uncertainties in CT-based image guidance and verification. Magnetic resonance imaging (MRI) is a well established imaging method for pelvic organs. In prostate cancer specifically, MRI accurately depicts prostate zonal anatomy, rectum, bladder, and pelvic floor structures with previously unseen precision owing to its sharp soft tissue contrast. The advantages of including MRI in the clinical workflow of prostate cancer radiotherapy are multifold. MRI allows for true adaptive radiotherapy to unfold based on daily MRI images taken before, during and after each radiotherapy fraction. It enables accurate dose escalation to the prostate and intraprostatic tumor lesions. Technically, MRI high-strength magnetic field and linear accelerator high energy electromagnetic beams are hardly compatible, and important efforts were made to overcome these technical challenges and integrate MRI and linear accelerator into one single treatment device, called MRI-linac. Different systems are produced by two leading vendors in the field and currently, there are around 100 MRI-linacs worldwide in clinical operations. In this narrative review paper, we discuss historical perspective of image guidance in radiotherapy, basic elements of MRI, current clinical developments in MRI-guided prostate cancer radiotherapy, and challenges associated with the use of MRI-linac in clinical practice.

Magnetic resonance picture of changes in the prostate gland in patients with localized prostate cancer after radical external beam radiotherapy

Introduction. Magnetic resonance imaging (MRI) is a highly informative imaging technique, but now days is not recommended for detecting prostate cancer revealing after external beam radiation therapy (EBRT) at localized prostate cancer.Purpose of the study. To study the magnetic resonance imaging of changes in the prostate gland in patients with localized prostate cancer after radical EBRT. Materials and methods. Studied and compared the data of clinical and histological studies of a series of MRI in nine patients with prostate cancer before and after EBRT. Standard sequences (T2-weighted images, diffusion-weighted images, dynamic con trast enhancement) were used for MRI. Results. After irradiation, in a delayed period, atrophy and fibrotic changes occur in the structure of the prostate gland, which leads to a decrease in its size, uneven contours, and the impossibility of differentiating the zonal anatomy on T2-VI. After RT, the intensity of the MR signal from the tumor on DWI with a high b-factor decreases, the difference in the ADC of the peripheral, transient zones and the tumor is practically leveled. After RT, the hypervascularity of the tumor progressively decreases, there fore, in the delayed period, in most cases, type 3 of the contrast curve is observed in DCE. In general, MRI gives results consistent with the dynamics of serum PSA levels. However, one patient after EBRT showed signs of local progression on MRI without signs of biochemical progression.Conclusion. MRI can be used as a method for early diagnosis of local recurrence of prostate cancer after EBRT, however, its clinical significance requires further study.

Zonal anatomy of the prostate using magnetic resonance imaging, morphometrics, and radiomic features: impact of age-related changes.

To evaluate the impact of age on the zonal anatomy of the prostate by MRI using morphometric and textural analysis. A total of 154 men (mean age: 63 years) who underwent MRI due to a high prostate-specific antigen (PSA) level were included retrospectively. At each MRI examination the following variables were measured: overall dimensions of the prostate (whole gland (WG), transitional zone (TZ), and peripheral zone (PZ)), and thickness of the anterior fibromuscular stroma (AFMS) and the periprostatic venous plexus (PPVP) on T2 weighted images. Identical regions of interest (ROIs) were delineated on the apparent diffusion coefficient (ADC) map on the anterior (horn) and posterior part of the PZ. Textural (TexRAD®) parameter differences between TZ and PZ ROIs on T2 weighted images were analyzed by linear regression. Results were correlated with age (distributed into five decades from 22 to 89 years). Age was positively correlated with PSA level and glandular volumes (WG, TZ, and TZ/WG ratio; p < 0.0001) and was negatively correlated with AFSM and PPVP thickness (p < 0.0001). There was a positive correlation between ADC values of the PZ and age (p = 0.003) and between entropy of the TZ and PZ and age (p < 0.001). Gradual variations in morphologic and textural features of the prostate were observed with age, mainly due to the increase in TZ volume while PZ volume tended to decrease. These modifications resulted in textural changes mainly at the expense of entropy. Entropy could be relevant for studying the process of aging of the prostate.

Local Staging of Prostate Cancer with Multiparametric MRI

Abstract Multiparametric magnetic resonance imaging (mpMRI) plays several valuable roles in preoperative staging of adenocarcinoma of the prostate gland, including detection of clinically significant disease, determination of extraglandular extension, and assessment of nodal disease. The Prostate Imaging Reporting and Data System (PI-RADS) establishes certain acceptable technical standards for mpMRI. These technical parameters allow for consistent image quality, enabling accurate detection and staging of disease; this in turn has significant implications for treatment recommendations. The prostate gland has a characteristic zonal anatomy, with cancers arising from the peripheral zone tending to demonstrate more aggressive histologic features. The acquisition of several sequences as part of mpMRI protocol allows for assessment of locoregional disease as well as regional and distant lymphadenopathy. The local staging of prostate cancer with mpMRI is reviewed in this article.

V14-03 TRANSURETHRAL WATER VAPOR ABLATION (STEAM) TO TREAT LOCALIZED PROSTATE CANCER (INVESTIGATIONAL USE ONLY)

You have accessJournal of UrologyProstate Oncology II & Testis Oncology & Misc. Oncology (V14)1 Sep 2021V14-03 TRANSURETHRAL WATER VAPOR ABLATION (STEAM) TO TREAT LOCALIZED PROSTATE CANCER (INVESTIGATIONAL USE ONLY) Christopher Dixon, and Christopher Warlick Christopher DixonChristopher Dixon More articles by this author , and Christopher WarlickChristopher Warlick More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002111.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Convective water vapor is a unique technology that uses the thermal energy of water vapor (steam) to ablate tissue. The objective was in vivo validation of Transurethral Vapor Ablation (TUVA) in men with clinically significant localized prostate cancer by; Group 1 - TUVA/RRP assessed by immediate whole mount sectioning, Group 2 - TUVA assessed by pre/post treatment MRI in an early feasibility trial and Both Groups by intraoperative real-time ultrasound and AE assessment. METHODS: A tabletop generator and a transurethral endoscopic delivery device, along with real-time TRUS, were used to direct water vapor into any anatomic zone of the prostate to ablate malignant prostate tissue. The procedure technique currently used, including the endoscopic and real-time ultrasound monitoring of needle deployment, advancement and vapor delivery is demonstrated. To evaluate the convective principles of TUVA, real-time ultrasound patterns of vapor delivery and 7-day post treatment gadolinium MRI images were studied. Ablation effectiveness was assessed in two independent groups. In Group 1 by whole mount sectioning immediately following TUVA / radical prostatectomy. In Group 2 by assessing pre- and 7-day post TUVA MRI nonenhancement patterns as well as PIRADSv2 resolution. Immediate safety was assessed by intraoperative inspection, gross examination of the prostate (Group 1) and immediate post op adverse events along with 7-day MRI’s (Group 2). RESULTS: Real-time ultrasound vapor patterns confirmed convective spread within the zonal anatomy and boundaries of the prostate. Real-time ultrasound during treatment demonstrated the convective principles and the ability to “see” the treatment. Collectively, whole mount sectioning along with the non-enhancing areas seen on MRI’s at 7-days demonstrated ablation to ALL anatomic zones and boundaries consistent with the unique ablation capabilities of convection. In Group 2, after one treatment session, 14/17 PIRADSv2 lesions ≥3 were no longer visible within the ablation zone on 7-day MRI. There were no serious adverse events intraoperatively or within one week of the treatment. CONCLUSIONS: Transurethral delivery of water vapor thermal energy can effectively ablate any zone of the prostate from apex to base, anterior to posterior, and laterally to the prostatic “capsule”. Early feasibility data using this investigational device are favorable. Source of Funding: Francis Medical, Maple Grove, MN © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e1165-e1166 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Christopher Dixon More articles by this author Christopher Warlick More articles by this author Expand All Advertisement Loading ...

MP05-19 MICRO-ULTRASOUND GUIDED PROSTATE BIOPSY IN PROSTATE CANCER DETECTION

You have accessJournal of UrologyProstate Cancer: Detection & Screening I (MP05)1 Sep 2021MP05-19 MICRO-ULTRASOUND GUIDED PROSTATE BIOPSY IN PROSTATE CANCER DETECTION Nino Karazanashvili, Kakha Barnovi, Inga Bakanova, and Guram Karazanashvili Nino KarazanashviliNino Karazanashvili More articles by this author , Kakha BarnoviKakha Barnovi More articles by this author , Inga BakanovaInga Bakanova More articles by this author , and Guram KarazanashviliGuram Karazanashvili More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001972.19AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Prostate cancer (PCa) is the second most commonly diagnosed cancer in males. A prostate biopsy is a gold standard in PCa diagnosis, but unnecessary biopsies and missed cancers are a subject of controversy, especially in the PSA gray zone (2-10ng/ml). EAU guidelines recommend the use of imaging to avoid unnecessary biopsies in males with a PSA in the gray zone. Prostate Micro-ultrasound (MUS) is a brand new and a very promising technology that operates at high frequency (29MHz), therefore it allows extremely precious visualization of the prostate that significantly improves detection of suspicious prostate lesions and provides the advantage of live targeting. Extremely few data exist on the use of MUS guided prostate biopsy (MUS-bx) for the diagnosis of prostate cancer. In this study, we present our pilot experience on MUS-bx in prostate cancer detection. METHODS: Between January 2020 and November 2020, a total of 146 men underwent transrectal prostate MUS-bx using a 29MHz transrectal probe. Prostate biopsies were performed in case of abnormally elevated PSA and/or suspicious prostatic imaging. All suspicious lesions were rated with the protocol of prostate risk identification using micro-ultrasound (PRI-MUS) by 3 urologists and a radiologist simultaneously. Suspicious prostate areas were biopsied whenever lesions were identified; in addition, 12 core systematic biopsies were performed in the same patients. Cancer detection rates were analyzed separately for targeted, systematic and targeted plus systematic biopsies. Totally 108 patients with mean PSA 12ng/ml (range 0.2-137ng/ml) did receive systematic plus targeted prostate biopsy. 79 (out of 108) patients with PSA 2-10ng/ml were analyzed separately. RESULTS: Of the 108 men enrolled in the analysis, PCa would be diagnosed via only targeted biopsy in 22% and via only systematic biopsy in 40%. But, targeted plus systematic biopsy detected prostate cancer in 44% of cases. Out of 79 patients with serum PSA levels 2-10ng/ml PCa detection rate with targeted, systematic, and targeted plus systematic biopsy was 23%, 38%, and 43% accordingly. CONCLUSIONS: MUS-bx is a very effective method of prostate cancer detection. It allows live targeting of the suspicious PCa lesions, perfect visualization of prostate zonal anatomy and consequent highly precious sampling of appropriate prostate zones. Due to these advantages, MUS-bx has the great potential to improve prostate cancer detection and to reduce unnecessary biopsies, especially in PSA gray zone. These findings need confirmation by further studies. Source of Funding: No funding was available © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e86-e86 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nino Karazanashvili More articles by this author Kakha Barnovi More articles by this author Inga Bakanova More articles by this author Guram Karazanashvili More articles by this author Expand All Advertisement Loading ...

Prospective Image Quality and Lesion Assessment in the Setting of MR-Guided Radiation Therapy of Prostate Cancer on an MR-Linac at 1.5 T: A Comparison to a Standard 3 T MRI.

Simple SummaryHigh-precision MR-guided radiotherapy (MRgRT) constitutes the state-of-the-art in the sphere of personalized prostate cancer treatment. To this end, integrating a 1.5 T scanner with a linear accelerator led to the development of MR-Linac (MRL), which could be considered a novel deflection point in radiation oncology. Since the success of both diagnosis and radiation treatment is highly dependent on image quality, geometric integrity, and lesion conspicuity, it is important to investigate the quality of these sequences in comparison to the current diagnostic gold standard multiparametric MRI at 3T (MRI3T), which has not been done before. The purpose of this study is to conduct a qualitative and a quantitative analysis of MRL-images at 1.5 T in patients undergoing MRgRT planning for prostate cancer. Results from this study pave the way for developing safer and more efficient planning workflows in patients with prostate cancer undergoing MR-guided radiotherapy.The objective of this study is to conduct a qualitative and a quantitative image quality and lesion evaluation in patients undergoing MR-guided radiation therapy (MRgRT) for prostate cancer on a hybrid magnetic resonance imaging and linear accelerator system (MR-Linac or MRL) at 1.5 Tesla. This prospective study was approved by the institutional review board. A total of 13 consecutive patients with biopsy-confirmed prostate cancer and an indication for MRgRT were included. Prior to radiation therapy, each patient underwent an MR-examination on an MRL and on a standard MRI scanner at 3 Tesla (MRI3T). Three readers (two radiologists and a radiation oncologist) conducted an independent qualitative and quantitative analysis of T2-weighted (T2w) and diffusion-weighted images (DWI). Qualitative outcome measures were as follows: zonal anatomy, capsule demarcation, resolution, visibility of the seminal vesicles, geometric distortion, artifacts, overall image quality, lesion conspicuity, and diagnostic confidence. All ratings were performed on an ordinal 4-point Likert scale. Lesion conspicuity and diagnostic confidence were firstly analyzed only on MRL. Afterwards, these outcome parameters were analyzed in consensus with the MRI3T. Quantitative outcome measures were as follows: anteroposterior and right left diameter of the prostate, lesion size, PI-RADS score (Prostate Imaging—Reporting and Data System) and apparent diffusion coefficient (ADC) of the lesions. Intergroup comparisons were computed using the Wilcoxon-sign rank test and t tests. A post-hoc regression analysis was computed for lesion evaluation. Finally, inter-/intra-reader agreement was analyzed using the Fleiss kappa and intraclass correlation coefficient. For T2w images, the MRL showed good results across all quality criteria (median 3 and 4). Furthermore, there were no significant differences between MRL and MRI3T regarding capsule demarcation or geometric distortion. For the DWI, the MRL performed significantly less than MRI3T across most image quality criteria with a median ranging between 2 and 3. However, there were no significant differences between MRL and MRI3T regarding geometric distortion. In terms of lesion conspicuity and diagnostic confidence, inter-reader agreement was fair for MRL alone (Kappa = 0.42) and good for MRL in consensus with MRI3T (Kappa = 0.708). Thus, lesion conspicuity and diagnostic confidence could be significantly improved when reading MRL images in consensus with MRI3T (Odds ratio: 9- to 11-fold for the T2w images and 5- to 8–fold for the DWI) (p < 0.001). For measures of lesion size, anterior-posterior and right-left prostate diameter, inter-reader and intersequence agreement were excellent (ICC > 0.90) and there were no significant differences between MRL and MRI3T among all three readers. In terms of Prostate Imaging Reporting and Data System (PIRADS) scoring, no significant differences were observed between MRL and MRI3T. Finally, there was a significant positive linear relationship between lesion ADC measurements (r = 0.76, p < 0.01) between the ADC values measured on both systems. In conclusion, image quality for T2w was comparable and diagnostic even without administration of spasmolytic- or contrast agents, while DWI images did not reach diagnostic level and need to be optimized for further exploitation in the setting of MRgRT. Diagnostic confidence and lesion conspicuity were significantly improved by reading MRL in consensus with MRI3T which would be advisable for a safe planning and treatment workflow. Finally, ADC measurements of lesions on both systems were comparable indicating that, lesion ADC as measured on the MRL could be used as a biomarker for evaluation of treatment response, similar to examinations using MRI3T.

Quality control and whole-gland, zonal and lesion annotations for the PROSTATEx challenge public dataset

PurposeRadiomic features are promising quantitative parameters that can be extracted from medical images and employed to build machine learning predictive models. However, generalizability is a key concern, encouraging the use of public image datasets. We performed a quality assessment of the PROSTATEx training dataset and provide publicly available lesion, whole-gland, and zonal anatomy segmentation masks. MethodTwo radiology residents and two experienced board-certified radiologists reviewed the 204 prostate MRI scans (330 lesions) included in the training dataset. The quality of provided lesion coordinate was scored using the following scale: 0 = perfectly centered, 1 = within lesion, 2 = within the prostate without lesion, 3 = outside the prostate. All clearly detectable lesions were segmented individually slice-by-slice on T2-weighted and apparent diffusion coefficient images. With the same methodology, volumes of interest including the whole gland, transition, and peripheral zones were annotated. ResultsOf the 330 available lesion identifiers, 3 were duplicates (1%). From the remaining, 218 received score = 0, 74 score = 1, 31 score = 2 and 4 score = 3. Overall, 299 lesions were verified and segmented. Independently of lesion coordinate score and other issues (e.g., lesion coordinates falling outside DICOM images, artifacts etc.), the whole prostate gland and zonal anatomy were also manually annotated for all cases. ConclusionWhile several issues were encountered evaluating the original PROSTATEx dataset, the improved quality and availability of lesion, whole-gland and zonal segmentations will increase its potential utility as a common benchmark in prostate MRI radiomics.

Three-dimensional ultrashort echo time (3D UTE) magnetic resonance imaging (MRI) of the normal and degenerative disco-vertebral complex at 4.7T: a feasibility study with longitudinal evaluation.

To assess feasibility of a three-dimensional ultrashort echo time (3D-UTE)-sequence to evaluate normal and pathological disco-vertebral complex (DVC), with assessment of its different portionsin a rat model of degenerative disk disease (DDD) with histological correlation.To assess whether this sequence, in comparison with long echo time T2-weighted sequence, is able to monitor DDD with differentiation of early from chronic DVC changes in pathological mechanical conditions. Five rats were induced with DDD model by percutaneous disk trituration of the tail with an 18-G needle under US-guidance and imaged at 4.7T. MRI protocol included fat-saturated-T2 (RARE) and 3D-UTE-sequences performed at baseline (day 0. n = 5 animals /10 DVC) and each week (W) from W1 to W10 postoperatively. Visual analysis and signal intensity measurements of SNR and CNR of all DVC portions were performed on RARE and UTE images. Following killing (baseline, n = 1/2 DVC; W2, n = 2/4 DVC; W10, n = 2/4 DVC), histological analysiswas performed and compared with MRI. In normal DVC, unlike conventionalRARE-sequences, 3D-UTEallowed complete identification of DVC zonal anatomy including on visual analysis and CNRmeasurements. In pathological conditions, SNR and CNR measurements of the annulus fibrosus and nucleus pulposus on 3D-UTE distinguished early discitis at W1 fromchronic discopathy (P < 0.001 for SNR and P < 0.001 for CNR). Neither the normal complete anatomy of the DVC nor its pathological patterns could be assessed on conventional sequences. Unlike conventional sequences, 3D-UTE enables visualization of the complete normal DVC anatomy and enables monitoring of DDD differentiating between earlyDVC changes from chronic ones. Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Interreader Agreement with Prostate Imaging Reporting and Data System Version 2 for Prostate Cancer Detection: A Systematic Review and Meta-Analysis.

We evaluated interreader agreement with PI-RADS® (Prostate Imaging Reporting and Data System) version 2 for detection of prostate cancer. We searched MEDLINE®, Embase® and the Cochrane Library between 2015 and June 3, 2019 to identify original research reporting interreader agreement in the use of PI-RADS version 2. Quality of the retrieved studies was assessed by 2 independent reviewers using the Guidelines for Reporting Reliability and Agreement Studies. Pooled κ for PI-RADS version 2 was calculated, and a head-to-head comparison with version 1 was performed for the available studies. Subgroup analysis was performed according to zonal anatomy (peripheral or transitional zone), cutoff value (4 or higher, or 3 or higher) and specific imaging sequences (T2-weighted, diffusion-weighted and dynamic contrast enhanced). Meta-regression analysis was performed to assess the cause of study heterogeneity. A total of 30 studies (4,095 patients) were included. Pooled κ of PI-RADS version 2 was 0.61 (95% CI 0.55-0.67). In 4 studies evaluating head-to-head comparisons PI-RADS versions 1 and 2 showed similar pooled κ values (0.61, 95% CI 0.33-0.90 vs 0.68, 95% CI 0.57-0.79; p=0.61). Substantial interreader agreement was noted with a cutoff of 4 or higher (κ=0.61) and moderate agreement was observed with a cutoff of 3 or higher (κ=0.57), peripheral zone (κ=0.64), transitional zone (κ=0.49) and the 3 magnetic resonance imaging sequences (κ 0.42-0.58). Difference in reader experience was the single significant factor affecting study heterogeneity (p=0.01). PI-RADS version 2 provides substantial interreader agreement in overall scoring in patients with suspicious prostate cancer, with a similar level of agreement to version 1.

Quality comparison between three-dimensional T2-weighted SPACE and two-dimensional T2-weighted turbo spin echo magnetic resonance images for the brachytherapy planning evaluation of prostate and periprostatic anatomy

PurposeThe purpose of this study was to compare an isotropic three-dimensional (3D) T2-weighted sequence sampling perfection with application-optimized contrasts by using flip angle evolution (SPACE) with an axial two-dimensional T2-weighted turbo spin echo (TSE) sequence with regard to overall image quality and the delineation of normal prostate and periprostatic anatomy for low-dose-rate prostate cancer brachytherapy planning evaluation. Methods and MaterialsPatients (n = 69) with prostate cancer who had pelvic magnetic resonance imaging (MRI) for low-dose-rate brachytherapy treatment planning were included. Three radiologists independently assessed the visibility of nine anatomic structures on each sequence by using a 5-point scale and overall image quality by using a 4-point scale. The significance of the differences in diagnostic performance was tested with a Wilcoxon signed rank test. ResultsNo significant intersequence differences were found for most (7/9) anatomical structures and overall image quality. The mean scores for visibility of anatomical structures on the 3D SPACE and 2D TSE sequences, respectively, were as follows: the zonal anatomy (3.7; 3.9, p = 0.05), prostate capsule (3.9; 4.0, p = 0.08), neurovascular bundle (2.9; 2.9, p = 0.9), rectoprostatic angle (3.8; 3.8, p = 0.35), rectum (4.2; 4.3, p = 0.26), urethra (3.8; 3.9, p = 0.12), urinary bladder (4.6; 4.6, p = 0.61), and overall image quality (2.9; 2.9, p = 0.33). 3D SPACE was superior for delineation of the genitourinary diaphragm (3.8; 3.6, p = 0.003), whereas 2D TSE was superior for delineation of the seminal vesicles (3.5; 4.0, p < 0.0001). ConclusionsAnatomic delineation of the prostatic and periprostatic anatomy provided by the 3D SPACE sequence is as robust in quality as that provided by a conventional 2D TSE sequence with superior delineation of the genitourinary diaphragm. For MRI-based brachytherapy treatment planning, the 3D SPACE sequence with subcentimeter isotropic resolution can replace the 2D TSE sequence and be incorporated into standard MRI protocols.

Patient preparation and image quality in female pelvic MRI: recommendations revisited.

To assess whether with recent MR technology current patient preparation literature recommendations for female pelvic MRI are still valid and how they are influencing the position of the female pelvic organs, image quality, and diagnostic confidence. This prospective study was performed in two centres. The effects of bladder filling (empty, moderate, full; n = 26), fasting, saturation band (n = 25), and menstrual cycle (n = 25) were assessed in healthy subjects in centre 1, while the effect of intravenous glucagon application was evaluated in 20 patients with benign conditions in centre 2. Images of the pelvis were acquired using 1.5-T MRI with T2-weighted turbo spin echo imaging in sagittal and (angulated) transaxial planes. The analysis was conducted hierarchically using paired Wilcoxon tests with an alpha significance level of 0.05. Urinary bladder filling influenced the cervix-to-uterine angle (p < 0.001) but had no clear effect on image quality (p > 0.05). A moderately full bladder provided the best delineation of fat between the bladder and uterus (p = 0.0009). A full bladder resulted in highest ovarian displacement (p = 0.0059). Timing within the menstrual cycle did not influence the depiction of zonal anatomy (p > 0.05). Fasting (p < 0.02) and saturation bands (p < 0.001) had a positive effect on image quality. Glucagon was associated with decreased MRI artefacts (p = 0.002). Fasting, antispasmodic agents, and saturation bands improved MR image quality and are recommended for female pelvic MRI. Urinary bladder filling influenced the cervix-to-uterine angle, but had no clear effect on image quality. • Fasting, saturation band, and glucagon injection significantly reduced bowel movement artefacts. • Depiction of the anatomical details of the uterus was not influenced by the timing of MRI within the menstrual cycle. • Although bladder filling did not impact diagnostic capabilities in healthy volunteers, in clinical practice, it may be useful to examine patients with a moderately full bladder, to reduce diagnostic inaccuracies.

Association Between Prostate Zonal Volume and Erectile Dysfunction in Patients With Benign Prostatic Hyperplasia.

IntroductionThe impact of prostate zonal volume on erectile function and penile Doppler parameters is not yet settled.AimTo assess the association between prostate zonal volume and erectile dysfunction in patients with benign prostatic hyperplasia.MethodsThis cross-sectional analytical study included 70 men (aged ≥ 40 years). Of them, 60 patients were assigned to 3 study groups (n = 20/each): group (A) patients who had lower urinary tract symptoms (LUTSs) and erectile dysfunction (ED), group (B) patients who had LUTSs with no ED, group (C) patients who had ED with no LUTS, and other 10 age-matched patients who had no LUTS or ED acted as a control group (D). All patients were subjected to detailed medical and sexual history. International prostate symptom score (IPSS) was used to assess LUTSs, and international index of erectile function (IIEF) was used to assess ED.Main Outcome MeasureTransrectal ultrasound and penile Doppler ultrasound were used to assess zonal anatomy of the prostate and the vascular pattern of erection.ResultsThere was a significant difference in IPSS between group A (26) and B (19) (P < .05). Each of groups A and C had significant lower peak systolic velocity (PSV) than each of groups B and D (P < .001/each). There was a significant positive correlation between transitional zone index (TZI) and IPSS (r = 0.71, P < .01), and significant negative correlation between TZI and both of IIEF (r = -0.48, P < .05) and PSV (r = -0.606, P < .05).ConclusionThis study clearly demonstrated that there were significant correlations between increased transitional zone volume, TZI, and decreased both of IIEF score and PSV.Qalawena MM, Al-Shatouri MA, Motawaa MA, et al. Association Between Prostate Zonal Volume and Erectile Dysfunction in Patients With Benign Prostatic Hyperplasia. Sex Med 2020;8:205–213.