peripheral zone
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Uro ◽  
2022 ◽  
Vol 2 (1) ◽  
pp. 21-29
Author(s):  
Yuichiro Oishi ◽  
Takeya Kitta ◽  
Takahiro Osawa ◽  
Takashige Abe ◽  
Nobuo Shinohara ◽  
...  

Prostate MRI scans for pre-biopsied patients are important. However, fewer radiologists are available for MRI diagnoses, which requires multi-sequential interpretations of multi-slice images. To reduce such a burden, artificial intelligence (AI)-based, computer-aided diagnosis is expected to be a critical technology. We present an AI-based method for pinpointing prostate cancer location and determining tumor morphology using multiparametric MRI. The study enrolled 15 patients who underwent radical prostatectomy between April 2008 and August 2017 at our institution. We labeled the cancer area on the peripheral zone on MR images, comparing MRI with histopathological mapping of radical prostatectomy specimens. Likelihood maps were drawn, and tumors were divided into morphologically distinct regions using the superpixel method. Likelihood maps consisted of pixels, which utilize the cancer likelihood value computed from the T2-weighted, apparent diffusion coefficient, and diffusion-weighted MRI-based texture features. Cancer location was determined based on the likelihood maps. We evaluated the diagnostic performance by the area under the receiver operating characteristic (ROC) curve according to the Chi-square test. The area under the ROC curve was 0.985. Sensitivity and specificity for our approach were 0.875 and 0.961 (p < 0.01), respectively. Our AI-based procedures were successfully applied to automated prostate cancer localization and shape estimation using multiparametric MRI.


2022 ◽  
Vol 6 (1) ◽  
Author(s):  
Chie Tsuruta ◽  
Kenji Hirata ◽  
Kohsuke Kudo ◽  
Naoya Masumori ◽  
Masamitsu Hatakenaka

Abstract Background We investigated the correlation between texture features extracted from apparent diffusion coefficient (ADC) maps or diffusion-weighted images (DWIs), and grade group (GG) in the prostate peripheral zone (PZ) and transition zone (TZ), and assessed reliability in repeated examinations. Methods Patients underwent 3-T pelvic magnetic resonance imaging (MRI) before radical prostatectomy with repeated DWI using b-values of 0, 100, 1,000, and 1,500 s/mm2. Region of interest (ROI) for cancer was assigned to the first and second DWI acquisition separately. Texture features of ROIs were extracted from comma-separated values (CSV) data of ADC maps generated from several sets of two b-value combinations and DWIs, and correlation with GG, discrimination ability between GG of 1–2 versus 3–5, and data repeatability were evaluated in PZ and TZ. Results Forty-four patients with 49 prostate cancers met the eligibility criteria. In PZ, ADC 10% and 25% based on ADC map of two b-value combinations of 100 and 1,500 s/mm2 and 10% based on ADC map with b-value of 0 and 1,500 s/mm2 showed significant correlation with GG, acceptable discrimination ability, and good repeatability. In TZ, higher-order texture feature of busyness extracted from ADC map of 100 and 1,500 s/mm2, and high gray-level run emphasis, short-run high gray-level emphasis, and high gray-level zone emphasis from DWI with b-value of 100 s/mm2 demonstrated significant correlation, excellent discrimination ability, but moderate repeatability. Conclusions Some DWI-related features showed significant correlation with GG, acceptable to excellent discrimination ability, and moderate to good data repeatability in prostate cancer, and differed between PZ and TZ.


Author(s):  
Caterina Gaudiano ◽  
Arianna Rustici ◽  
Beniamino Corcioni ◽  
Federica Ciccarese ◽  
Lorenzo Bianchi ◽  
...  

Multiparametric magnetic resonance imaging has been established as the most accurate non-invasive diagnostic imaging tool for detecting prostate cancer (PCa) in both the peripheral zone and the transition zone (TZ) using the PI-RADS (Prostate Imaging Reporting and Data System) version 2.1 released in 2019 as a guideline to reporting. Transition zone PCa remains the most difficult to diagnose due to a markedly heterogeneous background and a wide variety of atypical imaging presentations as well as other anatomical and pathological processes mimicking PCa. The aim of this paper was to present a spectrum of PCa in the TZ, as a guide for radiologists.


Author(s):  
Caterina Gaudiano ◽  
Lorenzo Bianchi ◽  
Antonio De Cinque ◽  
Beniamino Corcioni ◽  
Francesca Giunchi ◽  
...  

Author(s):  
Mohamed N. Hamza ◽  
Maged Maher Roshdy ◽  
Mouamen M. Seleet ◽  
Tamer M. El Raggal

Background: To evaluate the normative values of corneal endothelial cell parameters within a group of healthy young Egyptian adults using specular microscopy and to examine any correlations between endothelial parameters and refractive or biometric parameters.Methods: In this cross-sectional study, specular microscopy was used to study the right eyes of 150 healthy young volunteers and evaluated endothelial cell parameters, including cellular density, hexagonality (HEX), and coefficient of variation (CV) at 15 different points on the back corneal surface, which were later grouped into the central zone and either four quadrants or three annular zones. The same eyes underwent refractive and biometric assessments.Results: Hundred fifty healthy adults were examined, and the age ranged from 20 to 30 years, with a median of 23 (interquartile range, 21?27) years. The mean ± standard deviation of central cell density was 2902.7 ± 270.7 cells/mm2. The superior paracentral area had the lowest mean density (2895.8 cells/mm2), but the highest mean HEX (67.7%), while the inferior peripheral area had the highest mean density (3100.5 cells/ mm2) but the lowest mean HEX (64%). The difference in cell density among the three annular zones was not statistically significant (P = 0.365). However, HEX and CV in the central and paracentral zones differed statistically significantly from those of the peripheral zone (P < 0.001 and P = 0.014, respectively). Weak but non-significant correlations were detected between endothelial cell density and all measured refractive and biometric parameters.Conclusions: The findings of this study provided useful normative biometric and specular data in a specific age group and a specific population, and could be useful in planning intraocular surgery in young Egyptian adults. However, future longitudinal studies with a larger sample could refine more endothelial cell parameter specifications over time.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jörg Tamihardja ◽  
Sinan Cirsi ◽  
Patrick Kessler ◽  
Gary Razinskas ◽  
Florian Exner ◽  
...  

Abstract Background Evaluation of delivered dose to the dominant intraprostatic lesion (DIL) for moderately hypofractionated radiotherapy of prostate cancer by cone beam computed tomography (CBCT)-based dose accumulation and target coverage analysis. Methods Twenty-three patients with localized prostate cancer treated with moderately hypofractionated prostate radiotherapy with simultaneous integrated boost (SIB) between December 2016 and February 2020 were retrospectively analyzed. Included patients were required to have an identifiable DIL on bi-parametric planning magnetic resonance imaging (MRI). After import into the RayStation treatment planning system and application of a step-wise density override, the fractional doses were computed on each CBCT and were consecutively mapped onto the planning CT via a deformation vector field derived from deformable image registration. Fractional doses were accumulated for all CBCTs and interpolated for missing CBCTs, resulting in the delivered dose for PTVDIL, PTVBoost, PTV, and the organs at risk. The location of the index lesions was recorded according to the sector map of the Prostate Imaging Reporting and Data System (PIRADS) Version 2.1. Target coverage of the index lesions was evaluated and stratified for location. Results In total, 338 CBCTs were available for analysis. Dose accumulation target coverage of PTVDIL, PTVBoost, and PTV was excellent and no cases of underdosage in DMean, D95%, D02%, and D98% could be detected. Delivered rectum DMean did not significantly differ from the planned dose. Bladder mean DMean was higher than planned with 19.4 ± 7.4 Gy versus 18.8 ± 7.5 Gy, p < 0.001. The penile bulb showed a decreased delivered mean DMean with 29.1 ± 14.0 Gy versus 29.8 ± 14.4 Gy, p < 0.001. Dorsal DILs, defined as DILs in the posterior medial peripheral zone of the prostate, showed a significantly lower delivered dose with a mean DMean difference of 2.2 Gy (95% CI 1.3–3.1 Gy, p < 0.001) compared to ventral lesions. Conclusions CBCT-based dose accumulation showed an adequate delivered dose to the dominant intraprostatic lesion and organs at risk within planning limits. Cautious evaluation of the target coverage for index lesions adjacent to the rectum is warranted to avoid underdosage.


2021 ◽  
Author(s):  
Dimitris Zaridis ◽  
Eugenia Mylona ◽  
Nikolaos Tachos ◽  
Kostas Marias ◽  
Manolis Tsiknakis ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jeroen Bleker ◽  
Derya Yakar ◽  
Bram van Noort ◽  
Dennis Rouw ◽  
Igle Jan de Jong ◽  
...  

Abstract Objectives To investigate a previously developed radiomics-based biparametric magnetic resonance imaging (bpMRI) approach for discrimination of clinically significant peripheral zone prostate cancer (PZ csPCa) using multi-center, multi-vendor (McMv) and single-center, single-vendor (ScSv) datasets. Methods This study’s starting point was a previously developed ScSv algorithm for PZ csPCa whose performance was demonstrated in a single-center dataset. A McMv dataset was collected, and 262 PZ PCa lesions (9 centers, 2 vendors) were selected to identically develop a multi-center algorithm. The single-center algorithm was then applied to the multi-center dataset (single–multi-validation), and the McMv algorithm was applied to both the multi-center dataset (multi–multi-validation) and the previously used single-center dataset (multi–single-validation). The areas under the curve (AUCs) of the validations were compared using bootstrapping. Results Previously the single–single validation achieved an AUC of 0.82 (95% CI 0.71–0.92), a significant performance reduction of 27.2% compared to the single–multi-validation AUC of 0.59 (95% CI 0.51–0.68). The new multi-center model achieved a multi–multi-validation AUC of 0.75 (95% CI 0.64–0.84). Compared to the multi–single-validation AUC of 0.66 (95% CI 0.56–0.75), the performance did not decrease significantly (p value: 0.114). Bootstrapped comparison showed similar single-center performances and a significantly different multi-center performance (p values: 0.03, 0.012). Conclusions A single-center trained radiomics-based bpMRI model does not generalize to multi-center data. Multi-center trained radiomics-based bpMRI models do generalize, have equal single-center performance and perform better on multi-center data.


2021 ◽  
pp. 21-32
Author(s):  
Татьяна Анатольевна Бочкарева ◽  
Владимир Петрович Крючков ◽  
Танзиля Фаатовна Рудзинская

Исследование мотивов выбора педагогической профессии, базовой структуры мотивационной сферы, формирование реалистического представления о будущей профессии студентов логопедического профиля являются необходимым условием подготовки специалистов нового времени. На основе анализа мотивов студентов первых-четвертых курсов очной и заочной форм обучения были выделены «ядерные» мотивы: моральные (помощь детям); мотивы профессионально-педагогической направленности (любовь к детям, желание работать с детьми); социальные (востребованность на рынке труда); познавательные (самореализация и самосовершенствование); материальные (возможность частной практики и подработки) и утилитарные (короткий рабочий день, длинный отпуск). В зоне ближайшей периферии значимыми мотивами для обеих групп оказались социальные (социальная значимость) и творческие (творчество и многогранность профессии). Утилитарные мотивы в периферической зоне (отдельный кабинет, ценность опыта в интересах семьи), материальные (высокая зарплата), престижные (карьерный рост) мотивы более выражены у студентов заочной формы обучения. Выявленная динамика формирования мотивационных процессов свидетельствует о возрастании роли от младших курсов к старшим профессионально-педагогических, моральных, материальных, социальных и познавательных мотивов. Проанализированы мотивы выбора профессии «логопед» и динамика формирования мотивационных процессов с позиций психолого-педагогического подхода. Определены параметры анализа. Выделены мотивационные критерии, проведено их шкалирование и ранжирование с использованием теории функционально-семантических полей. Смоделированы и проанализированы ядерные и периферийные компоненты мотивационного поля. Определены основные направления в динамике формирования учебно-профессиональной мотивации. Выделены факторы, влияющие на динамику формирования мотивов выбора профессии: осознанность выбора профессии, погруженность в учебный процесс, возраст, форма обучения. The study of the motives for choosing a teaching profession, the basic structure of the motivational sphere, including speech therapy students, the formation of a realistic idea of the future profession are a necessary condition for training specialists of the new era. Based on the analysis of students’ of full-time and part-time forms of study, from the 1st to the 4th years, motives, the authors identify «core» motives: moral (helping children); motives of a professional and pedagogical orientation (love for children); social (being in demand in the labor market), cognitive (self-realization and self-improvement), material (the possibility of private practice and part-time work) and utilitarian (short working day, long vacation). In the zone of the immediate periphery, social (social significance) and creative (creativity and versatility of the profession) motives turned out to be significant for both groups. Utilitarian motives in the peripheral zone (a separate office, the value of experience in the interests of the family), financial, prestigious (career growth) motives are more represented among students of part-time form of study. The authors analyzed the motives for choosing the profession «speech therapist» and the dynamics of formation of motivational processes from the standpoint of the psychological and pedagogical approach. Researchers have identified motivational criteria, scaling and ranking them using the theory of functional-semantic fields. The researchers identified the factors influencing the dynamics of formation of the motives for choosing a profession: awareness of the choice of a profession, immersion in the educational process, age, form of education.


2021 ◽  
Vol 143 ◽  
pp. 109913
Author(s):  
Zhihua Li ◽  
Guangyu Dan ◽  
Vikram Tammana ◽  
Scott Johnson ◽  
Zheng Zhong ◽  
...  

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