Cyclic changes in T2* relaxometry of human uterus during the menstrual cycle using BOLD MR imaging.

PURPOSE: To evaluate dynamic changes of T2* values within the endometrium, junctional zone and myometrium during the menstrual cycle using blood oxygen level-dependent (BOLD) magnetic resonance imaging. METHOD: Volunteers underwent MRI scans on menstrual phase, ovulatory phase and luteal phase, including T2-weighted imaging and BOLD MR imaging. Multi-gradient-recalled echo (MGRE) sequence was used to obtain BOLD MR images. T2* values of different uterine layers, including endometrium, junctional zone and myometrium, on sagittal images were analyzed quantitatively. RESULTS: Twenty-four subjects calculated T2* values successfully. The T2* values of each zonal structure during menstruation were significantly lower than those during ovulatory phase (P < 0.05) and luteal phase (P < 0.001). The T2* value of junctional zone was significantly lower than that of the myometrium over all three menstrual phases (P = 0.000, menstrual; P = 0.000, ovulatory; P = 0.001, luteal). The mean T2* value in endometrium during the ovulatory phase was the highest of the uterine zones over menstrual cycle. During menstrual phase, there was no statistical difference between endometrium and junctional zone (P > 0.05). Conversely, the comparison of the T2* values between endometrium and myometrium, junctional zone and myometrium both showed significant difference (P = 0.000). The mean T2* values within endometrium during ovulatory phase and luteal phase were significantly higher than those within junctional zone and myometrium (P < 0.05). CONCLUSIONS: Cyclic changes of T2* values in each zonal structure of the uterus were revealed during the menstrual cycle by means of BOLD technique, which may be potentially beneficial in investigating dysmenorrhea, guiding assisted reproductive technologies and monitoring hypoxia in gynecological tumors.

Variability of manual segmentation of the prostate in axial T2-weighted MRI: A multi-reader study.

PURPOSE: To evaluate the interreader variability in prostate and seminal vesicle (SV) segmentation on T2w MRI. METHODS: Six readers segmented the peripheral zone (PZ), transitional zone (TZ) and SV slice-wise on axial T2w prostate MRI examinations of n = 80 patients. Twenty different similarity scores, including dice score (DS), Hausdorff distance (HD) and volumetric similarity coefficient (VS), were computed with the VISCERAL EvaluateSegmentation software for all structures combined and separately for the whole gland (WG = PZ + TZ), TZ and SV. Differences between base, midgland and apex were evaluated with DS slice-wise. Descriptive statistics for similarity scores were computed. Wilcoxon testing to evaluate differences of DS, HD and VS was performed. RESULTS: Overall segmentation variability was good with a mean DS of 0.859 (±SD = 0.0542), HD of 36.6 (±34.9 voxels) and VS of 0.926 (±0.065). The WG showed a DS, HD and VS of 0.738 (±0.144), 36.2 (±35.6 vx) and 0.853 (±0.143), respectively. The TZ showed generally lower variability with a DS of 0.738 (±0.144), HD of 24.8 (±16 vx) and VS of 0.908 (±0.126). The lowest variability was found for the SV with DS of 0.884 (±0.0407), HD of 17 (±10.9 vx) and VS of 0.936 (±0.0509). We found a markedly lower DS of the segmentations in the apex (0.85 ±â€¯0.12) compared to the base (0.87 ±â€¯0.10, p < 0.01) and the midgland (0.89 ±â€¯0.10, p < 0.001). CONCLUSIONS: We report baseline values for interreader variability of prostate and SV segmentation on T2w MRI. Variability was highest in the apex, lower in the base, and lowest in the midgland.

A Cellular Anatomy of the Normal Adult Human Prostate and Prostatic Urethra.

A comprehensive cellular anatomy of normal human prostate is essential for solving the cellular origins of benign prostatic hyperplasia and prostate cancer. The tools used to analyze the contribution of individual cell types are not robust. We provide a cellular atlas of the young adult human prostate and prostatic urethra using an iterative process of single-cell RNA sequencing (scRNA-seq) and flow cytometry on ∼98,000 cells taken from different anatomical regions. Immunohistochemistry with newly derived cell type-specific markers revealed the distribution of each epithelial and stromal cell type on whole mounts, revising our understanding of zonal anatomy. Based on discovered cell surface markers, flow cytometry antibody panels were designed to improve the purification of each cell type, with each gate confirmed by scRNA-seq. The molecular classification, anatomical distribution, and purification tools for each cell type in the human prostate create a powerful resource for experimental design in human prostate disease.

Analysis of topographical distribution of prostate cancer and related pathological findings in prostatectomy specimens using cMDX document architecture.

INTRODUCTION: Understanding the topographical distribution of prostate cancer (PCa) foci is necessary to optimize the biopsy strategy. This study was done to develop a technical approach that facilitates the analysis of the topographical distribution of PCa foci and related pathological findings (i.e., Gleason score and foci dimensions) in prostatectomy specimens. MATERIAL & METHODS: The topographical distribution of PCa foci and related pathologic evaluations were documented using the cMDX documentation system. The project was performed in three steps. First, we analyzed the document architecture of cMDX, including textual and graphical information. Second, we developed a data model supporting the topographic analysis of PCa foci and related pathologic parameters. Finally, we retrospectively evaluated the analysis model in 168 consecutive prostatectomy specimens of men diagnosed with PCa who underwent total prostate removal. The distribution of PCa foci were analyzed and visualized in a heat map. The color depth of the heat map was reduced to 6 colors representing the PCa foci frequencies, using an image posterization effect. We randomly defined 9 regions in which the frequency of PCa foci and related pathologic findings were estimated. RESULTS: Evaluation of the spatial distribution of tumor foci according to Gleason score was enabled by using a filter function for the score, as defined by the user. PCa foci with Gleason score (Gls) 6 were identified in 67.3% of the patients, of which 55 (48.2%) also had PCa foci with Gls between 7 and 10. Of 1173 PCa foci, 557 had Gls 6, whereas 616 PCa foci had Gls>6. PCa foci with Gls 6 were mostly concentrated in the posterior part of the peripheral zone of the prostate, whereas PCa foci with Gls>6 extended toward the basal and anterior parts of the prostate. The mean size of PCa foci with Gls 6 was significantly lower than that of PCa with Gls>6 (P<0.0001). CONCLUSION: The cMDX-based technical approach facilitates analysis of the topographical distribution of PCa foci and related pathologic findings in prostatectomy specimens.