Peripheral Zone Research Articles

Enhanced Image Processing Using Complex Averaging in Diffusion-Weighted Imaging of the Prostate: The Impact on Image Quality and Lesion Detectability.

Diffusion-weighted images of the prostate can suffer from a "hazy" background in low signal-intensity areas. We hypothesize that enhanced image processing (EIP) using complex averaging reduces artifacts, noise, and distortion in conventionally acquired diffusion-weighted images and synthesized high b-value images, thus leading to higher image quality and better detection of potentially malignant lesions. Conventional DWI trace images with a b-value of 1000 s/mm2 (b1000), calculated images with a b-value of 2000 s/mm2 (cb2000), and ADC maps of 3T multiparametric prostate MRIs in 53 patients (age 68.8 ± 10 years) were retrospectively evaluated. Standard images were compared to images using EIP. In the standard images, 36 lesions were detected in the peripheral zone and 20 in the transition zone. In 13 patients, EIP led to the detection of 8 additional lesions and the upgrading of 6 lesions; 6 of these patients were diagnosed with prostate carcinoma Gleason 7 or 8. EIP improved qualitative ratings for overall image quality and lesion detectability. Artifacts were significantly reduced in the cb2000 images. Quantitative measurements for lesion detectability expressed as an SI ratio were significantly improved. EIP using complex averaging led to image quality improvements in acquired and synthesized DWI, potentially resulting in elevated diagnostic accuracy and management changes.

Evaluating the Utility of Prostate-Specific Antigen Density in Risk Stratification of PI-RADS 3 Peripheral Zone Lesions on Non-Contrast-Enhanced Prostate MRI: An Exploratory Single-Institution Study.

Objective This study aimed to explore the potential of prostate-specific antigen density (PSAD) as a supplementary tool for defining high-risk Prostate Imaging Reporting and Data System (PI-RADS) 3 lesions in the peripheral zone on non-contrast-enhanced MRI. This additional stratification tool could supplement the decision-making process for biopsy, potentially helping in identifying higher-risk patients more accurately, minimizing unnecessary procedures in lower-risk patients, and limiting the need for dynamic contrast-enhanced (DCE) scans. Materials and methods Between January 2019 and April 2023, 30 patients with PI-RADS 3 lesions underwent MRI-ultrasound fusion biopsies at our institution. Age and PSAD values were investigated using logistic regression and chi-square automatic interaction detection (CHAID) analysis to discern their predictive value for malignancy. Results The mean patient age was 64.7 years, and the mean PSAD was 0.13 ng/mL2. Logistic regression demonstrated PSAD to be a significant predictor of cancer (p=0.012), but not age (p=0.855). CHAID analysis further identified a PSAD cut-off value of 0.12, below which the cancer detection rate was 23.1% and above which the rate increased to 76.5%. Conclusions This exploratory study suggests that PSAD might be utilized to enhance the stratification of high-risk PI-RADS 3 lesions in the peripheral zone on non-contrast-enhanced MRI, aiding in decision-making for biopsy. While biopsy remains the gold standard for definitive diagnosis, a high PSAD value may suggest a greater need for biopsy in this specific group. Although further validation in larger cohorts is required, our findings contribute to the ongoing discourse on optimizing PI-RADS 3 lesion management. Limitations include a small sample size, the retrospective nature of the study, and the single-center setting, which may impact the generalizability of our results.

Genetic robustness control of auxin output in priming organ initiation

Auxin signaling is essential for organ initiation in plants. How genetic robustness controls auxin output during organ initiation is largely unknown. Here, we identified DORNROSCHEN-LIKE (DRNL) as a target of MONOPTEROS (MP) that plays essential roles in organ initiation. We demonstrate that MP physically interacts with DRNL to inhibit cytokinin accumulation by directly activating ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 6 and CYTOKININ OXIDASE 6. DRN, the paralogous gene of DRNL, acts redundantly with DRNL but is not coexpressed with DRNL in the organ founder cells in which DRNL is expressed. We demonstrate that DRNL directly inhibits DRN expression in the peripheral zone, whereas DRN transcripts are ectopically activated in drnl mutants and fully restore the functional deficiency of drnl in organ initiation. Our results provide a mechanistic framework for the robust control of auxin signaling in organ initiation through paralogous gene-triggered spatial gene compensation effects.

Impact of Corneal Toricity on the Distribution of Corneal Epithelial Thickness.

To investigate the impact of corneal toricity on the distribution characteristics of corneal epithelial thickness (CET). A total of 330 eyes in 330 healthy participants were included in this study. They were divided into two groups based on the median of the corneal toricity value: low-toricity group (corneal toricity < 1.50 diopters) and high-toricity group (corneal toricity ≥ 1.50 diopters). The CET within a 9-mm-diameter area of the central cornea was obtained using optical coherence tomography. The difference of CET value between flat and steep meridians (F-S CET) was defined to evaluate the CET distribution. The F-S CET between the two groups was compared, and the correlations between F-S CET and the corneal toricity were analyzed. The CET was thinner in the superior-peripheral area than in other areas. A slight intergroup difference was noted in terms of the F-S CET at the paracentral (0.11 ± 0.93 vs 0.32 ± 0.92, P = .038), midperipheral (0.45 ± 0.78 vs 0.77 ± 0.89, P = .001), and peripheral (3.11 ± 2.18 vs 4.10 ± 2.38, P < .001) zone. In each zone, the difference in F-S CET between the two groups was less than 1 μm. As the area expanded, the F-S CET continued to increase (F = 850.303, P < .001). A weak correlation was observed between F-S CET and corneal toricity (r = 0.103 to 0.240); however, this correlation was not significant in the paracentral zone. Covariance analysis demonstrated that F-S CET was slightly correlated with age, refractive state, and intraocular pressure. The corneal toricity did not significantly affect the distribution of the corneal epithelium in normal corneas. [J Refract Surg. 2023;39(7):482-490.].

The role of tumor density in predicting significant cancer on targeted biopsy of the prostate.

Multiparametric magnetic resonance imaging (mpMRI) is central to diagnosing prostate cancer; however, not all imaged lesions represent clinically significant tumors. We aimed to evaluate the association between the relative tumor volume on mpMRI and clinically significant prostate cancer on biopsy. We retrospectively reviewed the medical records of 340 patients who underwent combined transperineal targeted and systematic prostate biopsies between 2017 and 2021. Tumor volume was estimated based on the mpMRI diameter of suspected lesions. Relative tumor volume (tumor density) was calculated by dividing the tumor and prostate volumes. The study outcome was clinically significant cancer on biopsy. Logistic regression analyses were used to evaluate the association between tumor density and the outcome. The cutoff for tumor density was determined with ROC curves. Median estimated prostate and peripheral zone tumor volumes were 55cm3 and 0.61cm3, respectively. Median PSA density was 0.13 and peripheral zone tumor density was 0.01. Overall, 231 patients (68%) had any cancer and 130 (38%) had clinically significant cancer. On multivariable logistic regression age, PSA, previous biopsy, maximal PI-RADS score, prostate volume, and peripheral zone tumor density were significant predictors of outcome. Using a threshold of 0.006, the sensitivity, specificity, positive and negative predictive values of peripheral zone tumor density were 0.9, 0.51, 0.57, and 0.88, respectively. Peripheral zone tumor density is associated with clinically significant prostate cancer in patients with PI-RADS 4 and 5 mpMRI lesions. Future studies are required to validate our findings and evaluate the role of tumor density in avoiding unnecessary biopsies.

Differences in the pathogenetic characteristics of prostate cancer in the transitional and peripheral zones and the possible molecular biological mechanisms.

Since the theory of modern anatomical partitioning of the prostate was proposed, the differences in the incidence and pathological parameters of prostate cancer between the peripheral zone and transition zone have been gradually revealed. It suggests that there are differences in the pathogenic pathways and molecular biology of prostate cancer between different regions of origin. Over the past decade, advances in sequencing technologies have revealed more about molecules, genomes, and cell types specific to the peripheral and transitional zones. In recent years, the innovation of spatial imaging and multiple-parameter magnetic resonance imaging has provided new technical support for the zonal study of prostate cancer. In this work, we reviewed all the research results and the latest research progress in the study of prostate cancer in the past two decades. We summarized and proposed several vital issues and focused directions for understanding the differences between peripheral and transitional zones in prostate cancer.

DWI CAPACITY IN PROSTATE CANCER DIAGNOSING

Relevance: Prostate cancer is one of the leading causes of cancer deaths in men worldwide. Transrectal ultrasound-guided (TRUS) prostate biopsy is the most important diagnostic step, without which a definitive diagnosis cannot be made. Despite this, TRUS-guided prostate biopsy has a high rate of false negatives and is often accompanied by various clinical complications. Multiparametric MRI (mpMRI) is now widely used in routine urological and oncological practice. An element of mpMRI is diffusion-weighted imaging (DWI), which is successfully used in detecting and localizing clinically significant prostate cancer.&#x0D; The study aimed to evaluate the DWI capacity in diagnosing prostate cancer.&#x0D; Methods: 52 patients, 48-86 years old, with suspected prostate cancer, underwent mpMRI. DWI sequences obtained using T2-weighted imaging (T2WI) were compared with each other and compared with the anatomical structure of the prostate. Suspicious prostate cancer sites were marked as regions of interest, for which an apparent diffusion coefficient (ADC) was calculated. A 12-point TRUS-guided biopsy confirmed the presence or absence of prostate cancer.&#x0D; Results: When analyzing quantitative measurements, ADC showed low values for cancer in the central gland (transitional zone and central zone) – 0.610±0.157×10-3 mm2/s, p=0.0001, and for cancer in the peripheral zone – 0.651±0.228×10-3 mm2/s, p=0.0004, compared to normal tissue. It was found that the highest sensitivity value (87.5%) is typical for ADC central gland, and the lower value for ADC peripheral zone is 75%. The highest specificity value (90.9%) was observed in ADC peripheral zone, and a lower value in ADC central gland – was 84.1%.&#x0D; Conclusion: DWI is an effective non-invasive method for detecting and localizing prostate cancer, providing a qualitative (visual) and quantitative assessment of prostate cancer.

DWI CAPACITY IN PROSTATE CANCER DIAGNOSING

Relevance: Prostate cancer is one of the leading causes of cancer deaths in men worldwide. Transrectal ultrasound-guided (TRUS) prostate biopsy is the most important diagnostic step, without which a definitive diagnosis cannot be made. Despite this, TRUS-guided prostate biopsy has a high rate of false negatives and is often accompanied by various clinical complications. Multiparametric MRI (mpMRI) is now widely used in routine urological and oncological practice. An element of mpMRI is diffusion-weighted imaging (DWI), which is successfully used in detecting and localizing clinically significant prostate cancer.&#x0D; The study aimed to evaluate the DWI capacity in diagnosing prostate cancer.&#x0D; Methods: 52 patients, 48-86 years old, with suspected prostate cancer, underwent mpMRI. DWI sequences obtained using T2-weighted imaging (T2WI) were compared with each other and compared with the anatomical structure of the prostate. Suspicious prostate cancer sites were marked as regions of interest, for which an apparent diffusion coefficient (ADC) was calculated. A 12-point TRUS-guided biopsy confirmed the presence or absence of prostate cancer.&#x0D; Results: When analyzing quantitative measurements, ADC showed low values for cancer in the central gland (transitional zone and central zone) – 0.610±0.157×10-3 mm2/s, p=0.0001, and for cancer in the peripheral zone – 0.651±0.228×10-3 mm2/s, p=0.0004, compared to normal tissue. It was found that the highest sensitivity value (87.5%) is typical for ADC central gland, and the lower value for ADC peripheral zone is 75%. The highest specificity value (90.9%) was observed in ADC peripheral zone, and a lower value in ADC central gland – was 84.1%.&#x0D; Conclusion: DWI is an effective non-invasive method for detecting and localizing prostate cancer, providing a qualitative (visual) and quantitative assessment of prostate cancer.

Peritumoral Radiomics Strategy Based on Ensemble Learning for the Prediction of Gleason Grade Group of Prostate Cancer

To develop and evaluate a peritumoralradiomic-based machine learning model to differentiate low-Gleason grade group (L-GGG) and high-GGG (H-GGG) prostate lesions. In this retrospective study, a total of 175 patients with prostate cancer (PCa) confirmed by puncture biopsy were recruited and included 59 patients with L-GGG and 116 patients with H-GGG. The original PCa regions of interest (ROIs) were delineated on T2-weighted (T2WI), diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) maps, and then centra-tumoral and peritumoral ROIs were defined. Features were meticulously extracted from each ROI to establish radiomics models, employing distinct sequence datasets. Peritumoral radiomics models were specifically developed for both the peripheral zone (PZ) and transitional zone (TZ), utilizing dedicated PZ and TZ datasets, respectively. The performances of the models were evaluated by using the receiver operating characteristic (ROC) curve and precision-recall curve. The classification model with combined peritumoral features based on T2+DWI+ADC sequence dataset demonstrated superior performance compared to the original tumor and centra-tumoral classification models. It achieved an area under the ROC curve (AUC) of 0.850 [95% confidence interval, 0.849, 0.860] and an average accuracy of 0.950. The combined peritumoral model outperformed the regional peritumoral models with AUC of 0.85 versus 0.75 for PZ lesions and 0.88 versus 0.69 for TZ lesions, respectively. The peritumoral classification models exhibit greater efficacy in predicting PZ lesions as opposed to TZ lesions. The peritumoral radiomics features showed excellent performance in predicting GGG in PCa patients and might be a valuable addition to the non-invasive assessment of PCa aggressiveness.

Образ глубинки в российских и немецких СМИ

The article considers the media image of the hinterland as objectifying the categories of social exclusion, social inclusion based on the material of the National Corpus of the Russian Language newspaper subcorps and the system of the Berlin-Brandenburg Academy of Sciences digital dictionaries (German). For the purpose of a more in-depth description of this media image, the article also provides a characteristic of a close media image of the province. The research paper establishes synonymic row of units representing the media image of the hinterland, it considers the lexeme of the same name in Russian (glubinka) and the Hinterland lexeme in German as key ones; within the media image of the province key lexemes are provintsiia and Provinz. In the structure of the hinterland media image in both languages, nuclear and peripheral zones and their constituent groups of linguistic means are distinguished: adjectives (derived from horonyms); spatial qualifiers; units nominating the subject; descriptives; deictic units; constructions of opposition (within the framework of the opposition «center – not the center»), verbal units of various actions; constructions of negation. The paper establishes that the media image of the province, compared with the media image of the hinterland, is structured to a lesser extent in the factual material and is positioned mainly within the framework of the opposition «capital – province» (Russian), «city – province» (German), while the socio-cultural stereotyping of this image in the German language is noted. A certain pattern of the social exclusion and social inclusion actualization processes in media texts is revealed. In the Russian language, the media image of the hinterland in the texts of the central media reflects both the processes of social exclusion and inclusion (to a lesser extent); in the texts of regional media – mainly the processes of social inclusion. In German, the reflection of these processes is directly related to the designated territory. The article comes to a conclusion about the national and cultural coloring of the hinterland media image. In the Russian language, this image is characterized by ambivalence (static, problematic / “Russianness”, authenticity, cultural potential). In the German language, the national and cultural specificity of the media image is due to the geographical and spatial location of the territory described.

Optimal length and temporal resolution of dynamic contrast-enhanced MR imaging for the differentiation between prostate cancer and normal peripheral zone tissue.

The value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in the detection of prostate cancer is controversial. There are currently insufficient peer reviewed published data or expert consensus to support routine adoption of DCE-MRI for clinical use. Thus, the objective of this study was to explore the optimal temporal resolution and measurement length for DCE-MRI to differentiate cancerous from normal prostate tissue of the peripheral zone of the prostate by non-parametric MRI analysis and to compare with a quantitative MRI analysis. Predictors of interest were onset time, relative signal intensity (RSI), wash-in slope, peak enhancement, wash-out and wash-out slope determined from non-parametric characterisation of DCE-MRI intensity-time profiles. The discriminatory power was estimated from C-statistics based on cross validation. We analyzed 54 patients with 97 prostate tissue specimens (47 prostate cancer, 50 normal prostate tissue) of the peripheral zone, mean age 63.8 years, mean prostate-specific antigen 18.9 ng/mL and mean of 10.5 days between MRI and total prostatectomy. When comparing prostate cancer tissue with normal prostate tissue, median RSI was 422% vs 330%, and wash-in slope 0.870 vs 0.539. The peak enhancement of 67 vs 42 was higher with prostate cancer tissue, while wash-out (-30% vs -23%) and wash-out slope (-0.037 vs -0.029) were lower, and the onset time (32 seconds) was comparable. The optimal C-statistics was 0.743 for temporal resolution of 8.0 seconds and measurement length of 2.5 minutes compared with 0.656 derived from a quantitative MRI analysis. This study provides evidence that the use of a non-parametric approach instead of a more established parametric approach resulted in greater precision to differentiate cancerous from normal prostate tissue of the peripheral zone of the prostate.

Tumor localization by Prostate Imaging and Reporting and Data System (PI-RADS) version 2.1 predicts prognosis of prostate cancer after radical prostatectomy

An improved reading agreement rate has been reported in version 2.1 (v2.1) of the Prostate Imaging and Reporting and Data System (PI-RADS) compared with earlier versions. To determine the predictive efficacy of bi-parametric MRI (bp-MRI) for biochemical recurrence (BCR), our study assessed PI-RADS v2.1 score and tumor location in Japanese prostate cancer patients who underwent radical prostatectomy. Retrospective analysis was performed on the clinical data of 299 patients who underwent radical prostatectomy at Chiba University Hospital between 2006 and 2018. The median prostate-specific antigen (PSA) level before surgery was 7.6 ng/mL. Preoperative PI-RADS v2.1 categories were 1–2, 3, 4, and 5 in 35, 56, 138, and 70 patients, respectively. Tumor location on preoperative MRI was 107 in the transition zone (TZ) and 192 in the peripheral zone (PZ). BCR-free survival was significantly shorter in the PZ group (p = 0.001). In the total prostatectomy specimens, preoperative PI-RADS category 5, radiological tumor location, pathological seminal vesicle invasion, and Grade Group ≥ 3 were independent prognostic factors of BCR. These four risk factors have significant potential to stratify patients and predict prognosis. Radiological tumor location and PI-RADS v2.1 category using bp-MRI may enable prediction of BCR following radical prostatectomy.

Development and validation of nomogram to improve the specificity of multiparametric MRI for clinically significant prostate cancer.

To develop and validate a nomogram to improve the specificity of prostate imaging reporting and data system (PI-RADS) on multiparametric magnetic resonance imaging (MRI) for clinically significant prostate cancer on targeted fusion biopsy. A retrospective review of patients who underwent fusion biopsy for PI-RADS 3-5 lesions using UroNav and Artemis systems between 2016 and 2022 was performed. Patients were divided into those with CS disease on fusion biopsy (Gleason grade group ≥2) versus those without. Multivariable analysis was used to identify variables associated with CS disease. A 100-point nomogram was constructed, and ROC curve was generated. 1485 lesions (1032 patients) were identified, 510 (34%) were PI-RADS 3, 586 (40%) were PI-RADS 4, and 389 (26%) were PI-RADS 5. Of these, 11% of PI-RADS 3, 39% of PI-RADS 4, and 61% of PI-RADS 5 showed CS disease. CS disease was associated with older age (OR 1.04, 95% CI 1.02-1.06, p < 0.01), previous negative biopsy (OR 0.52, 95% CI 0.36-0.74, p < 0.01), presence of multiple PI-RADS 3-5 lesions (OR 0.61, 95% CI 0.45-0.83, p < 0.01), peripheral zone location (OR 1.88, 95% CI 1.30-2.70, p < 0.01), PSA density (OR 1.48 per 0.1 unit, 95% CI 1.33-1.64, p < 0.01), PI-RADS score 4 (OR 3.28, 95% CI 2.21-4.87, p < 0.01), and PI-RADS score 5 (OR 7.65, 95% CI 4.93-11.85, p < 0.01). Area under ROC curve was 82% for nomogram compared to 75% for PI-RADS score alone. We report a nomogram that combines PI-RADS score with other clinical parameters. The nomogram outperforms PI-RADS score for the detection of CS prostate cancer.

Prevalence and grade of malignancy differences with respect to the area of involvement in multiparametric resonance imaging of the prostate in the diagnosis of prostate cancer using the PI-RADS version 2 classification.

The peripheral zone is histologically different from the transitional zone. The aim of this study is to analyze the differences between the prevalence and grade of malignancy of mpMRI-targeted biopsies that involve the TZ with respect to the PZ. A cross-sectional study of 597 men evaluated for PC screening between February 2016 and October 2022 was conducted. Exclusion criteria were prior BPH surgery, radiotherapy, 5-alpha-reductase inhibitors treatment, UTI, mixed involvement of PZ-TZ or doubts, and central-zone involvement. Hypothesis contrast test was used to study differences proportions of malignancy (ISUP > 0) and significant (ISUP > 1) and high-grade tumor (ISUP > 3) in PI-RADSv2 > 2-targeted biopsies in PZ with respect to TZ, and logistic regression and hypothesis contrast tests were used to study the influence of the area of exposure as an effect-modifying factor in the diagnosis of malignancy with respect to the PI-RADSv2 classification. 473 patients were selected and 573 lesions biopsied (127 PI-RADS3, 346 PI-RADS4 and 100 PI-RADS5). A significant increase was described in the proportion of malignancy and significant and high-grade tumor in PZ compared to TZ (22.6%, 21.3%, and 8.7%, respectively). Significant increase in proportions and malignancy were described in cores targeted to PZ with respect to TZ, highlight the differences between PZ and TZ for ST (37.3%vs23.7% for PI-RADS4, 69.2%vs27.3% for PI-RADS5, respectively). Statistically significant linear trend was described increasing for malignancy, significant and high-grade tumors with respect to the PI-RADSv2 scores (change > 10%). Although the prevalence and grade of malignancy in the TZ is lower than in the PZ, PI-RADS4 and 5-targeted biopsies should not be omitted in this location, but PI-RADS3 could be.

MULTIPLE CALCIFIED HAMARTOMATOUS PHLEBOLITHS IN BUCCAL MUCOSA

The presence of asymptomatic irregular radiopacities in soft tissues in the maxillofacial region produced by calcified thrombi characterizes phleboliths. These vary from 1 to 5 mm in diameter, and there is no specific localization or gender preference. A 24-year-old woman with no pertinent past medical history presented nodules of various sizes and non-pulsative consistency upon bimanual palpation of posterior region of the left buccal mucosa. These were not related to paresthesia or dysphasia but were painful. Laboratory blood tests were within normal ranges. Upon computed tomography, numerous calcifications of unequal size were suspected to be venous stones. Invasive treatment was performed with surgical removal through excisional biopsy. Histopathologically, the lesion revealed concentric deposition of calcified lamellae with central foci of calcified amorphous amphophilic material. A peripheral zone lined by smooth muscle tissue compatible with vascular walls was also found. The final diagnosis was multiple calcified hamartomatous phleboliths. The presence of asymptomatic irregular radiopacities in soft tissues in the maxillofacial region produced by calcified thrombi characterizes phleboliths. These vary from 1 to 5 mm in diameter, and there is no specific localization or gender preference. A 24-year-old woman with no pertinent past medical history presented nodules of various sizes and non-pulsative consistency upon bimanual palpation of posterior region of the left buccal mucosa. These were not related to paresthesia or dysphasia but were painful. Laboratory blood tests were within normal ranges. Upon computed tomography, numerous calcifications of unequal size were suspected to be venous stones. Invasive treatment was performed with surgical removal through excisional biopsy. Histopathologically, the lesion revealed concentric deposition of calcified lamellae with central foci of calcified amorphous amphophilic material. A peripheral zone lined by smooth muscle tissue compatible with vascular walls was also found. The final diagnosis was multiple calcified hamartomatous phleboliths.

Short-Term Axial Length Changes in Myopic Eyes Induced by Defocus Spectacles for Myopia Control

Background. This study tested short-term axial length changes with Lenstar using a simple peripheral plus-add spectacle design. Methods. The subjects for this study were current users of monofocal glasses or contact lenses, aged 18–25 years, with myopic spherical refractions ranging from −1.00 to −5.00 diopters in both eyes. This study tested subjects while using a pair of special defocus spectacles that possess a central zone with the distance myopic correction and a peripheral zone with +3.50 added diopters. The procedure consisted of reading an online book with black letters on white background on a desktop computer, in two periods—one with the usual spectacles and the second with special defocus spectacles. Before and after these periods, 10 axial length measurements of the right eye were made with Lenstar and averaged up to three decimal points. Results. Seventeen subjects (thirteen female and four male; mean age 22.3 ± 5.5 years) participated in this study. The mean spherical equivalent of their right eye was −2.31 ± 1.06 diopters. There was a significant difference of +8.1 microns which increased the axial length from baseline when reading the usual prescription levels during the first 40 min period. When subjects read in the same situation with the defocus spectacles, the axial length significantly returned to baseline measurements, which were shortened by −10.6 microns. Conclusions. The decrease in axial length with these spectacles might indicate an effect on axial elongation signals from the choroid. These spectacles could be tested for myopia control purposes.

ULTRA-WIDEFIELD OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN MILD FAMILIAL EXUDATIVE VITREORETINOPATHY.

To investigate ultra-widefield optical coherence tomography angiography (UWF-OCTA) to detect and evaluate mild familial exudative vitreoretinopathy and compare the detective ratio of UWF-OCTA with ultra-widefield scanning laser ophthalmoscopy and ultra-widefield fluorescein angiography. The patients with familial exudative vitreoretinopathy were included in this study. UWF-OCTA, using a 24- × 20-mm montage, was performed for all patients. All images were independently tested for the presence of familial exudative vitreoretinopathy-associated lesions. Statistical analysis was performed with SPSS V.24.0. Forty-six eyes of 26 participants were included in the study. Ultra-widefield optical coherence tomography angiography was found to be greatly superior to ultra-widefield scanning laser ophthalmoscopy in detecting peripheral retinal vascular abnormality ( P < 0.001) and peripheral retinal avascular zone ( P < 0.001). The detection rates of peripheral retinal vascular abnormality, peripheral retinal avascular zone, retinal neovascularization, macular ectopia, and temporal midperipheral vitreoretinal interface abnormality were comparable with ultra-widefield fluorescein angiography images ( P > 0.05). Furthermore, vitreoretinal traction (17/46, 37%) and small foveal avascular zone (17/46, 37%) were detected effectively on UWF-OCTA. Ultra-widefield optical coherence tomography angiography is a reliable noninvasive tool to detect familial exudative vitreoretinopathy lesions, especially in mild patients or asymptomatic family members. The unique manifestation of UWF-OCTA offers an alternative to ultra-widefield fluorescein angiography for the screening and diagnosis of FEVR.

Longitudinal monitoring of Apparent Diffusion Coefficient (ADC) in patients with prostate cancer undergoing MR-guided radiotherapy on an MR-Linac at 1.5 T: a prospective feasibility study.

Hybrid MRI linear accelerators (MR-Linac) might enable individualized online adaptation of radiotherapy using quantitative MRI sequences as diffusion-weighted imaging (DWI). The purpose of this study was to investigate the dynamics of lesion apparent diffusion coefficient (ADC) in patients with prostate cancer undergoing MR-guided radiation therapy (MRgRT) on a 1.5T MR-Linac. The ADC values at a diagnostic 3T MRI scanner were used as the reference standard. In this prospective single-center study, patients with biopsy-confirmed prostate cancer who underwent both an MRI exam at a 3T scanner (MRI3T) and an exam at a 1.5T MR-Linac (MRL) at baseline and during radiotherapy were included. Lesion ADC values were measured by a radiologist and a radiation oncologist on the slice with the largest lesion. ADC values were compared before vs. during radiotherapy (during the second week) on both systems via paired t-tests. Furthermore, Pearson correlation coefficient and inter-reader agreement were computed. A total of nine male patients aged 67 ± 6 years [range 60 - 67 years] were included. In seven patients, the cancerous lesion was in the peripheral zone, and in two patients the lesion was in the transition zone. Inter-reader reliability regarding lesion ADC measurement was excellent with an intraclass correlation coefficient of (ICC) > 0.90 both at baseline and during radiotherapy. Thus, the results of the first reader will be reported. In both systems, there was a statistically significant elevation of lesion ADC during radiotherapy (mean MRL-ADC at baseline was 0.97 ± 0.18 × 10-3 mm2/s vs. mean MRL-ADC during radiotherapy 1.38 ± 0.3 × 10-3 mm2/s, yielding a mean lesion ADC elevation of 0.41 ± 0.20 × 10-3 mm2/s, p < 0.001). Mean MRI3T-ADC at baseline was 0.78 ± 0.165 × 10-3 mm2/s vs. mean MRI3T-ADC during radiotherapy 0.99 ± 0.175 × 10-3 mm2/s, yielding a mean lesion ADC elevation of 0.21 ± 0.96 × 10-3 mm2/s p < 0.001). The absolute ADC values from MRL were consistently significantly higher than those from MRI3T at baseline and during radiotherapy (p < = 0.001). However, there was a strong positive correlation between MRL-ADC and MRI3T-ADC at baseline (r = 0.798, p = 0.01) and during radiotherapy (r = 0.863, p = 0.003). Lesion ADC as measured on MRL increased significantly during radiotherapy and ADC measurements of lesions on both systems showed similar dynamics. This indicates that lesion ADC as measured on the MRL may be used as a biomarker for evaluation of treatment response. In contrast, absolute ADC values as calculated by the algorithm of the manufacturer of the MRL showed systematic deviations from values obtained on a diagnostic 3T MRI system. These preliminary findings are promising but need large-scale validation. Once validated, lesion ADC on MRL might be used for real-time assessment of tumor response in patients with prostate cancer undergoing MR-guided radiation therapy.

Deep Regional Fluid Pathways in an Extensional Setting: The Role of Transfer Zones in the Hot and Cold Degassing Areas of the Larderello Geothermal System (Northern Apennines, Italy)

AbstractHigh‐temperature geothermal areas are often characterized by widespread surficial manifestations, whose location is strictly controlled by sets of faults of regional relevance. The geochemical and isotopic signature of the discharged fluids can reveal key information on the geothermal fluids pathway, shedding light on the sources and fluid‐rock interaction within the geothermal reservoirs. In this paper, a geochemical and structural data set from the Larderello geothermal area and surroundings is presented and discussed. We constrain the role of transfer and normal faults in controlling the geothermal circulation enhanced by a cooling magmatic intrusion underneath the Lago area (SW of Larderello). The structural control on the fluids circulation is highlighted by both the location of the CO2 emissions along the fault segments, where permeability is enhanced, and their degassing rates, which increase moving away from the core of the Larderello geothermal system. The main results unravel the presence of deep regional pathways along which endogenous fluids circulate before being discharged in the investigated areas. The peripheral zone emissions are affected by interaction with shallow aquifers and condensation processes whereas the CO2 emitted from the central areas, located near the core of the geothermal system, was accompanied by high amounts of steam, and suffers intense shallow fractionation processes. The latter areas emit medium‐to‐low normalized‐CO2‐degassing rates (&lt;270 t d−1 km−2) when compared to the extremely high values occurring in the peripheral sectors (up to 1,300 t d−1 km−2) of the Larderello geothermal systems, possibly suggesting an incipient propagation of such a system, likely wider than previously thought.

Subtrochanteric femoral fracture: an unusual first manifestation of prostate carcinoma. A case report

Background: Prostate cancer is a prevalent malignancy, particularly among older males, characterized by slow growth. Late presentation is common due to its peripheral zone origin. Lower urinary tract symptoms (LUTS), back pain, and anemia are frequently associated with prostate carcinoma. Pathologic fractures resulting from prostate carcinoma are relatively rare due to its blastic nature, and it is even more unusual for a fracture to be the initial presentation. Case Report: We present the case of a 75-year-old male who experienced a pathological fracture in the left subtrochanteric region of the femur as the first manifestation of prostate cancer. This case highlights the need for a ultidisciplinary team approach in managing such cases. Conclusion:The occurrence of a subtrochanteric femur fracture as the initial presentation of prostate cancer is a rare phenomenon. This case underscores the importance of considering prostate cancer as a possible underlying cause of atypical fractures and emphasizes the need for a multidisciplinary approach to ensure optimal patient care and management.