MRI and PSMA PET/CT of Biochemical Recurrence of Prostate Cancer.

Prostate cancer may recur several years after definitive treatment, such as prostatectomy or radiation therapy. A rise in serum prostate-specific antigen (PSA) level is the first sign of disease recurrence, and this is termed biochemical recurrence. Patients with biochemical recurrence have worse survival outcomes. Radiologic localization of recurrent disease helps in directing patient management, which may vary from active surveillance to salvage radiation therapy, androgen-deprivation therapy, or other forms of systemic and local therapy. The likelihood of detecting the site of recurrence increases with higher serum PSA level. MRI provides optimal diagnostic performance for evaluation of the prostatectomy bed. Prostate-specific membrane antigen (PSMA) PET radiotracers currently approved by the U.S. Food and Drug Administration demonstrate physiologic urinary excretion, which can obscure recurrence at the vesicourethral junction. However, MRI and PSMA PET/CT have comparable diagnostic performance for evaluation of local recurrence after external-beam radiation therapy or brachytherapy. PSMA PET/CT outperforms MRI in identifying recurrence involving the lymph nodes and bones. Caveats for use of both PSMA PET/CT and MRI do exist and may cause false-positive or false-negative results. Hence, these techniques have complementary roles and should be interpreted in conjunction with each other, taking the patient history and results of any additional prior imaging studies into account. Novel PSMA agents at various stages of investigation are being developed, and preliminary data show promising results; these agents may revolutionize the landscape of prostate cancer recurrence imaging in the future. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. See the invited commentary by Turkbey in this issue. The slide presentation from the RSNA Annual Meeting is available for this article.

Knowing the ABCs: teaching the principles of radiology to medical students in Turkey.

BACKGROUND: Radiology education in Turkey is mainly taught during clinical years of medical school and often lacks main principles. Exposure to the fundamentals of radiology at an early stage of medical education may drastically help students generate a better understanding of radiology and expand their interest in the specialty. With the Principles of Radiology Course that we provided, pre- and post-session tests, and assessment survey at the end of the course, we aimed to evaluate the effectiveness of such an online course among Turkish medical students. METHODS: A total of nine online sessions on imaging modalities principles was developed by radiology professors. Each session was given through Zoom by radiologists from different U.S.-institutions to Turkish medical students from state (n = 33) and private (n = 8) universities. Pretests and post-tests were given to participants via Qualtrics before and after each session, respectively. Paired two-sample t-tests were conducted to detect the variance and p=-.05 was used as the significance level. An evaluation survey was distributed at the end of the course to collect their feedback through SurveyMonkey. RESULTS: A total of 1,438 predominantly Turkish (99.32%) medical students engaged with this course. An average of 506 students completed both pre-test and post-test. There was a statistically significant (p < .001) increase in the scores in post-test (mean[range]:7.58[5.21-8.53]) relative to pre-test (mean[range]:5.10[3.52-8.53]). Four hundred and thirty-nine participants (F/M:63.33%/35.54%) completed the end-of-course survey. A total of 71% and 69.70% of the participants strongly agreed that the course would be useful in their clinical practice and had increased their understanding of radiology. They also reported that their level of confidence in the subjects had increased 68% and reached a weighted average of 3.09/4. The survey revealed that 396 (90.21%) of the participants strongly or somewhat agree that introductory principles and concepts should be presented in earlier years of medical education. Compared to in-person education, 358 (81.55%) found the course extremely or very convenient. CONCLUSION: Online lecture series consisting of the principles of the radiological imaging modalities can be offered to Turkish medical students to enhance their grasp of the various imaging modalities and their correct clinical application.

Acoustic propagation in gassy intertidal marine sediments: An experimental study.

The need to predict acoustic propagation through marine sediments that contain gas bubbles has become increasingly important for civil engineering and climate studies. There are relatively few in situ acoustic wave propagation studies of muddy intertidal sediments, in which bubbles of biogenic gas (generally methane, a potent greenhouse gas) are commonly found. We used a single experimental rig to conduct two in situ intertidal acoustical experiments to improve understanding of acoustic remote sensing of gassy sediments, eventually including gas bubble size distributions. In the first experiment, we measured sediment sound speed and attenuation between four aligned hydrophones for a quasi-plane wave propagating along the array. The second experiment involved a focused insonified sediment volume created by two transducers emitting coincident sound beams at different frequencies that generated bubble-mediated acoustic signals at combination frequencies. The results from sediment core analyses, and comparison of in situ acoustic velocity and attenuation values with those of water-saturated sediments, together provide ample evidence for the presence of in situ gas bubbles in the insonified volumes of sediments. These datasets are suitable for linear and non-linear inversion studies that estimate in situ greenhouse gas bubble populations, needed for future acoustical remote sensing applications.

TST, QuantiFERON-TB Gold test and T-SPOT.TB test for detecting latent tuberculosis infection in patients with rheumatic disease prior to anti-TNF therapy.

Introduction: Before starting tumour necrosis factor (TNF)-α blocking agents, standard tests should be used for the diagnosis of tuberculosis infection. The specificity of traditional tuberculin skin test (TST) is low in immunosuppressed patients due to prior Bacille Calmette Guérin (BCG) vaccination, non-tuberculous mycobacteria infections, false positive and negative results. In this study, we aimed to compare TST and Interferon-Gamma Release Assay (IGRA) tests for detecting latent tuberculosis infection in patients with rheumatic disease planned to receive TNF-α blocking agents. Materials and Methods: One hundred and nine patients (45 male, 64 female) with the diagnosis of rheumatoid arthritis (RA) (n= 70) and ankylosing spondylitis (AS) (n= 39) were included in the study. Age, sex, number of BCG scar, results of TST (using the Mantoux method), QuantiFERON-TB Gold test and T-SPOT.TB test were recorded for all patients. Correlation between the tests was assessed by Pearson correlation coefficient. Result: The mean age of RA and AS patients were 50 ± 13 (19-78 years). The prevalence of latent tuberculosis was 43.1% for TST, 39.4% for QuantiFERON-TB Gold test and 13.8% for T-SPOT.TB test, compared with the evaluation using the composite criteria such as close contact with active tuberculosis infection and/or suspicious fibrotic/calcific lesions on chest X-Ray without active tuberculosis infection. There was a moderate correlation between BCG scar number and TST (p< 0.001, r= 0.495), T-SPOT.TB test and QuantiFERON-TB Gold test (p= 0.007, r= 0.406), T-SPOT.TB test and composite criteria (p= 0.024, r= 0.343). The specificity of QuantiFERON-TB Gold test was 85.7%, and sensitivity was 73.9% for all patients with rheumatic disease. It was 73.5% and 66.7% for T-SPOT.TB test, respectively. The specificity of TST was 60.3% and sensitivity was 47.8% for TST. Conclusions: IGRA tests are not affected prior vaccination and useful for detecting latent tuberculosis infection in patients treated with corticosteroid due to lack of correlation between test negativity and corticosteroid therapy. Also, they are useful tests for diagnosis of latent tuberculosis infection as an alternative to TST due to their specificity and sensitivity.

Acoustic wave propagation in gassy porous marine sediments: The rheological and the elastic effects.

The preceding paper in this series [Mantouka, Dogan, White, and Leighton, J. Acoust. Soc. Am. 140, 274-282 (2016)] presented a nonlinear model for acoustic propagation in gassy marine sediments, the baseline for which was established by Leighton [Geo. Res. Lett. 34, L17607 (2007)]. The current paper aims further advancement on those two studies by demonstrating the particular effects of the sediment rheology, the dispersion and dissipation of the first compressional wave, and the higher order re-scattering from other bubbles. Sediment rheology is included through the sediment porosity and the definition of the contact interfaces of bubbles with the solid grains and the pore water. The intrinsic attenuation and the dispersion of the compressional wave are incorporated using the effective fluid density model [Williams, J. Acoust. Soc. Am. 110, 2276-2281 (2001)] for the far field (fully water-saturated sediment). The multiple scattering from other bubbles is included using the method of Kargl [J. Acoust. Soc. Am. 11, 168-173 (2002)]. The overall nonlinear formulation is then reduced to the linear limit in order to compare with the linear theory of Anderson and Hampton [J. Acoust. Soc. Am. 67, 1890-1903 (1980)], and the results for the damping coefficients, the sound speed, and the attenuation are presented.

Splenic cysts: clues in sonographic differential diagnosis and a new role for twinkling artifact.

AIM: Our aim was to investigate the frequency of various splenic cysts, to define the sonographic differential diagnostic clues and to introduce the value of twinkling artefact in the diagnosis of epidermoid splenic cysts. MATERIAL AND METHODS: All the splenic cysts imaged by ultrasound in 3 university hospitals during the period of 2005 to 2022 were recorded, followed-up and analyzed. RESULTS: One hundred seventy-one patients with splenic cysts were detected and these were classified and 73% of the cysts were simple. Ten cysts were epidermoid cysts as proven by post-operative final histology. CONCLUSION: Cystic splenic lesions are rare. Most of them are small simple cysts. Epidermoid cysts are larger in volume, constitute 6% of the total and can be differentiated by the help of twinkling artefact by Doppler ultrasound.

Spatial modelling of rheumatoid arthritis in Turkey by geographic information systems (GIS).

We described the recent spatial distribution of rheumatoid arthritis in Turkey and assessed the role of environmental variables in this distribution. We developed an observed rheumatoid arthritis (RA) incidence grid map by using georeferenced rheumatoid arthritis case data (2011) from the centres of 81 provinces and the kriging method with a spherical variogram model in geographic information systems (GIS). We also modelled rheumatoid arthritis incidence in GIS by using complementary spatial database including the grid map layers of 14 environmental variables of Turkey. We conducted principle component analysis and multiple regression to investigate the relationships among variables and develop a model, respectively. The produced model was run in GIS to obtain a predicted (model) RA map. We tested the reliability of the model map by residual statistics and found the model map dependable. Observed and model incidence maps revealed the geographic distribution of rheumatoid arthritis cases in Turkey. The mean temperature, minimum temperature, maximum temperature, water vapour pressure, elevation, potential evapotranspiration, latitude, distance to seas, sunshine fraction, precipitation, longitude and aspect variables were found to have significant impacts on rheumatoid arthritis. Consequently, the model incidence map established a good background to predict rheumatoid arthritis cases following environmental changes.

Relationship between hepatic and pancreatic steatosis and the COVID-19 pneumonia total severity score and prognosis with an emphasis on prognostic strength

PURPOSE: To investigate the relationship between hepatic steatosis (HS), pancreatic steatosis (PS), and coexisting HS and PS and the Coronavirus disease-2019 (COVID-19) pneumonia total severity score (TSS) and prognosis, assessed through computed tomography (CT), and to evaluate the degree of effectiveness of the three steatosis conditions on TSS and prognosis. METHODS: This retrospective study involved 461 patients (255 male and 206 female, median age of 53 years) with COVID-19 who underwent unenhanced chest CT. HS, PS, and coexisting HS and PS, assessed through CT, were compared with patient demographics, comorbidities, TSS, hospitalization and intubation requirements, and mortality rates. The parameters were compared using Mann-Whitney U and chi-square tests. The parameters of three groups of patients with only HS, only PS, and both HS and PS were compared using the Kruskal-Wallis test. RESULTS: Results revealed that TSS (P < 0.001 for all) and hospitalization rates (P < 0.001 for all except for HS [P = 0.004]) were higher in patients with HS, PS, and both than in those without. Intubation (P = 0.003) and mortality rates (P = 0.018) were significantly higher solely in patients with PS. However, TSS, hospitalization, and diabetes mellitus were significantly higher than in age-standardized analyses for PS. In a comparison between only HS, only PS, and coexisting HS and PS in 210 patients, the highest TSS was in the coexistence group (P < 0.001). CONCLUSION: The TSS and hospitalization rates correlate with HS, PS, and coexisting HS and PS, whereas intubation and mortality rates only correlate with PS. However, TSS correlates with coexisting HS and PS at the highest rate.

Seeing Radiology Curricula Through Turkish Medical Students' Eyes: A Survey of Turkish Medical Schools' Radiology Education.

INTRODUCTION: Radiology education is essential for nonradiologist specialists and practitioners as well as for radiologists. We conducted a survey to gather the opinions of Turkish medical students from first to sixth grade regarding their radiology curricula, radiology education content, and perceptions of various imaging modalities and to assess the amount, adequacy, and homogeneity of radiology education in various schools. METHODS: Turkish medical students were reached by student ambassadors from 10 different schools of medicine via social media and email. They were provided with a 20-question survey-via the SurveyMonkey platform-related to their radiology curriculum and their perceptions of the radiology education at their schools and of different imaging modalities. Subjective parameters were scaled by a 4-point Likert scale and the results are reported by percentages of students. RESULTS: A total of 988 medical students (F/M: 61%/39%) from 41 different medical schools participated in this survey. Of those, 57% were preclinical students (≤ third year of medical school), while 43% were clinical students (> third year). More than half of the students (51%) stated that the amount of radiology education included in their curriculum was too little, while 44% of them stated it was just right and only 5% stated it was too much. Only 31% of the participants stated that they were able to review radiology images on their own. When asked about their level of confidence in identifying the position of lines and tubes, pneumonia, pneumothorax, and pleural effusion on chest radiographs, 41%, 39%, 41%, and 41% of the participants, respectively, stated that they were not confident. Thirty-five percent of the participants had not received any training in comparing normal to abnormal imaging of bone fractures, pneumonia, pleural effusion, subdural hemorrhage, or pneumothorax. The majority of the Turkish medical students in this survey had never heard (57%) nor used (64%) the American College of Radiology Appropriateness Criteria. CONCLUSIONS: The radiology curriculum in Turkey differs among various schools and most students stated that preclinical radiology course content was inadequate. Further studies and improvements must be conducted to provide high-quality, equitable radiology education that begins during preclinical training with respect to the students' opinions.

The RSNA Cervical Spine Fracture CT Dataset.

This dataset is composed of cervical spine CT images with annotations related to fractures; it is available at https://www.kaggle.com/competitions/rsna-2022-cervical-spine-fracture-detection/.

Computed tomography evaluation of pancreatic steatosis: correlation with COVID-19 prognosis.

Aim: To investigate the relationship between pancreatic steatosis (PS) assessed on computed tomography (CT) and COVID-19 prognosis. Materials & methods: This retrospective study covers 396 patients with COVID-19 (mean age: 52.50 ± 16.86 years), who underwent unenhanced chest CT. PS was compared with clinical findings, comorbidities, requirements for hospitalization, intubation and intensive care unit (ICU), length of hospitalization and death. Results: PS was found to be strongly correlated with the severity of clinical findings and hospitalization rates (p < 0.001). In hospitalized patients, length of hospitalization (p = 0.002) and rates of ICU requirement (p = 0.003) were higher in patients with PS. Conclusion: PS, correlated with clinical severity and hospitalization requirement, is an independent risk factor for COVID-19.

Extramural venous invasion (EMVI) revisited: a detailed analysis of various characteristics of EMVI and their role as a predictive imaging biomarker in the neoadjuvant treatment response in rectal cancer.

PURPOSE: To assess whether size, diameter, and large vein involvement of MR-detected extramural venous invasion (MR-EMVI) have an impact on neoadjuvant therapy response in rectal adenocarcinoma. METHODS: 57 patients with locally advanced rectal adenocarcinoma scanned with MRI before and after neoadjuvant therapy were included. Two abdominal radiologists evaluated the images with special emphasis on EMVI, on initial staging and after neoadjuvant treatment. The sensitivity and specificity of MRI for detection of rest EMVI were determined. The association of various MR-EMVI characteristics including number, size, and main vein involvement with treatment response was investigated. In subjects with discordance of radiology and pathology, elastin stain was performed, and images and slides were re-evaluated on site with a multidisciplinary approach. RESULTS: At initial evaluation, 17 patients were MR-EMVI negative (29.8%) and 40 were MR-EMVI positive (70.2%). Complete/near-complete responders had less number (mean 1.45) and smaller diameter of MR-EMVI (mean 1.8 mm), when compared with partial responders (2.54 and 3.3 mm; p < 0.005). The sensitivity of MRI for rest EMVI detection was high, specificity was moderate, and in one patient elastin stain changed the final decision. In five patients with rest MR-EMVI positivity, carcinoma histopathologically had a distinctive serpiginous perivascular spread, growing along the track of vascular bundle, although it did not appear in intravascular spaces. CONCLUSION: This study demonstrates that not only the presence, but also size and number of EMVI that may be significant clinically and thus these parameters also ought to be incorporated to the MRI evaluation and prognostication of treatment response. From pathology perspective, tumors growing alongside major vessels may also reflect EMVI even if they are not demonstrably "intravascular."

An intrathyroidal nodule consisting of papillary thyroid cancer and ectopic hyperechoic parathyroid adenoma: a case report.

A 53-year-old woman with fatigue lasting for 6 weeks and increased parathormone level underwent a neck ultrasound. It revealed a large, lobulated, solid intrathyroidal nodule consisting of hypoechoic component with microcalcifications and hy-perechoic component with vascularity on Doppler mode. There were also subcentimetric intrathyroidal hypo- and hyperechoic nodules. Upon the diagnosis of papillary thyroid cancer on fine-needle aspiration biopsy, a total thyroidectomy procedure was performed. In the histopathologic evaluation, the hypoechoic component was diagnosed as papillary thyroid cancer, while the hyperechoic component was diagnosed as ectopic parathyroid adenoma. Subcentimetric nodules were demonstrated as multi-foci of papillary thyroid cancer.

Determinants of Pancreatic Steatosis: A Retrospective Observational Study.

BACKGROUND Metabolic syndrome affects 35% of the adult population in developed countries associated with non-alcoholic steatohepatitis, insulin resistance, and cardiovascular events. Fatty infiltration of the pancreas, or pancreatic steatosis, is a risk factor for acute pancreatitis, pancreatic malignancies, and diabetes mellitus, yet its relationship with metabolic syndrome is not well defined. METHODS We performed a single-centered retrospective observational study of 322 healthy subjects (subjects volunteering to be kidney transplant donors, mean age=46.3±13.5, 163 men and 159 women) in the last 2 years (July 2018-February 2020) from our institution. Pancreatic steatosis and hepatosteatosis were confirmed by computed tomography. RESULTS Pancreatic steatosis was present in 26.3% (85/322) of the subjects, and this finding correlated with age, body mass index (BMI), male sex, a family history of diabetes, creatinine, cystatin C, uric acid, low-density lipoprotein (LDL) cholesterol, triglycerides, glycemia, hemoglobin, transverse body diameter, and subcutaneous fat thickness levels by univariable logistic regression. On multiple linear regression only age (95% CI 1.01, 1.06), BMI (95% CI 1.01, 1.19), male sex (95% CI 1.49-5.99), uric acid (95% CI 1.01, 1.76), and subcutaneous fat thickness levels (95% CI 1.21-2.36) remained independently associated with pancreatic steatosis. CONCLUSION Pancreatic steatosis is common and associated with obesity, elevated serum uric acid, subcutaneous fat thickness, and male sex. Future studies are needed to evaluate if there are specific clinical consequences to the presence of pancreatic steatosis.

Deep COVID DeteCT: an international experience on COVID-19 lung detection and prognosis using chest CT.

The Coronavirus disease 2019 (COVID-19) presents open questions in how we clinically diagnose and assess disease course. Recently, chest computed tomography (CT) has shown utility for COVID-19 diagnosis. In this study, we developed Deep COVID DeteCT (DCD), a deep learning convolutional neural network (CNN) that uses the entire chest CT volume to automatically predict COVID-19 (COVID+) from non-COVID-19 (COVID-) pneumonia and normal controls. We discuss training strategies and differences in performance across 13 international institutions and 8 countries. The inclusion of non-China sites in training significantly improved classification performance with area under the curve (AUCs) and accuracies above 0.8 on most test sites. Furthermore, using available follow-up scans, we investigate methods to track patient disease course and predict prognosis.

Radiological approach to COVID-19 pneumonia with an emphasis on chest CT.

Coronavirus disease 2019 (COVID-19) has recently become a worldwide outbreak with several millions of people infected and more than 160.000 deaths. A fast and accurate diagnosis in this outbreak is critical to isolate and treat patients. Radiology plays an important role in the diagnosis and management of the patients. Among various imaging modalities, chest CT has received attention with its higher sensitivity and specificity rates. Shortcomings of the real-time reverse transcriptase-polymerase chain reaction test, including inappropriate sample collection and analysis methods, initial false negative results, and limited availability has led to widespread use of chest CT in the diagnostic algorithm. This review summarizes the role of radiology in COVID-19 pneumonia, diagnostic accuracy of imaging, and chest CT findings of the disease.

Role of Electronic Relaxation in the Injection Process of Organic Push-Pull Dyes in Complete Dye-Sensitized Solar Cells.

There is a growing consensus that the charge separation taking place in dye-sensitized solar cells is a multiscale process occurring on a times scale from a few to hundreds of picoseconds. We studied the excited-state dynamics of the robust and efficient push-pull dye RK1 in solution, on mesoporous films and in complete photovoltaics cells by femtosecond fluorescence upconversion and transient absorption. In a polar environment and cells, the dynamics at early times are dominated by an intramolecular electronic relaxation, while electron injection is predominant on thin films only. In cells, the electron injection process becomes visible at a later stage, from tens to hundreds of picoseconds. Our study shows that it is crucial to record and analyze full time-resolved fluorescence spectra in order to obtain wavelength-independent dynamics and get a correct description of the nature and the population of the excited state.

Numerical simulation of the nonlinear ultrasonic pressure wave propagation in a cavitating bubbly liquid inside a sonochemical reactor.

We investigate the acoustic wave propagation in bubbly liquid inside a pilot sonochemical reactor which aims to produce antibacterial medical textile fabrics by coating the textile with ZnO or CuO nanoparticles. Computational models on acoustic propagation are developed in order to aid the design procedures. The acoustic pressure wave propagation in the sonoreactor is simulated by solving the Helmholtz equation using a meshless numerical method. The paper implements both the state-of-the-art linear model and a nonlinear wave propagation model recently introduced by Louisnard (2012), and presents a novel iterative solution procedure for the nonlinear propagation model which can be implemented using any numerical method and/or programming tool. Comparative results regarding both the linear and the nonlinear wave propagation are shown. Effects of bubble size distribution and bubble volume fraction on the acoustic wave propagation are discussed in detail. The simulations demonstrate that the nonlinear model successfully captures the realistic spatial distribution of the cavitation zones and the associated acoustic pressure amplitudes.