Total exposure to ionizing radiation has nearly doubled in the last two decades. This increase is primarily due to increased computed tomography (CT) exposure. Concerns have been raised about the risks associated with patients' exposure to medical imaging radiation, which can increase a person's lifetime risk of developing cancer. Preventing unnecessary examinations becomes critical at this point. To avoid unnecessary examinations, it is necessary to understand the demanding process. To ascertain clinicians' awareness of and reasons for requesting a CT examination. We developed an online questionnaire that included 20 questions about clinicians' awareness of radiation safety and their reasons for requesting a CT examination, as well as demographic information such as age, gender, and year of medical practice experience. Additionally, we asked participants the number of CT scans requested in a month, the patients' questions and approaches about the imaging method, the effect of the patient's previous imaging history on the current imaging request, whether they believed that they had sufficient information about radiation doses, and whether they requested CT without an indication. We administered the questionnaire to clinicians from a variety of different professions in four different cities. A total of 195 clinicians participated. Internal medicine specialists were the most crowded group (38/195, 19.5%). Mean age of the population was 33.66 ± 5.92 years. Mean year of experience was 9.01 ± 5.96. Mean number of requested CT scans in a month was 36.88 ± 5.86. Forty-five (23.1%) participants stated that they requested CT scans without clinical indication. The most common reasons for CT scan requests were work load, fear of malpractice, and patient demand/insistence. CT scan requests are influenced by a variety of factors, both internal and external to the doctors and patients. Raising awareness of radiation safety and reducing fear of malpractice by limiting the number of patients per physician may result in a reduction in unnecessary CT examinations and ionizing radiation exposure.

Objective: There is limited and contradictory information about pulmonary perfusion changes detected with dual energy computed tomography (DECT) in COVID-19 cases. The purpose of this study was to define lung perfusion changes in COVID-19 cases with DECT, as well as to reveal any possible links between perfusion changes and laboratory findings. Methods: Patients who had a positive RT-PCR for SARS-CoV-2 and a contrast-enhanced chest DECT examination were included in the study. The pattern and severity of perfusion deficits were evaluated, as well as the relationships between perfusion deficit severity and laboratory results and CT severity ratings. The paired t-test, Wilcoxon test, and Student’s t-test were used to examine the changes in variables and perfusion deficits. p < 0.05 was regarded as statistically significant. Results: Study population consisted of 40 patients. Mean age was 60.73 ± 14.73 years. All of the patients had perfusion deficits at DECT images. Mean perfusion deficit severity score of the population was 8.45 ± 4.66 (min.-max, 1–19). In 24 patients (60%), perfusion deficits and parenchymal lesions matched completely. In 15 patients (37.5%), there was partial match. D dimer, CRP levels, CT severity score, and perfusion deficit severity score all had a positive correlation Conclusions: Perfusion deficits are seen not only in opacification areas but also in parenchyma of normal appearance. The CT severity score, CRP, D-dimer, and SpO2 levels of the patients were determined to be related with perfusion deficit severity. Advances in knowledge: Findings of the current study may confirm the presence of micro-thrombosis in COVID-19 pneumonia.

Introduction: Diagnostic discrimination between acute appendicitis (AA) and mesenteric lymphadenitis (AML) may require more diagnostic tests or great skill after excluding other diagnoses. This study aimed to make a differential diagnosis between AA and AML patients with previous and new parameters and to examine which parameters should be taken into account regarding whether the AML patient should be hospitalized or discharged. Material and methods: One hundred and twenty-three AML and 134 AA patients, randomly selected, were included in the study. Demographic, clinical, and laboratory data of all subjects were analyzed. Ultrasonographic and rarely computed tomography examinations evaluating for the enlarged lymph nodes with the shortest diameter in the right lower quadrant of the AML patients were performed. Also, the erect abdominal radiographs (EAR) of AML and AA patients were evaluated. Results: While there was no statistically significant difference in age or gender, C-reactive protein, white blood cell count, monocyte percentage as well as symptoms between the AA and AML groups (p > 0.05), neutrophil and lymphocyte percentage, appearance of EAR and L/M ratio were significantly different between the two groups (p < 0.05). There was no correlation between the short-axis diameter of the mesenteric lymph node and clinical and laboratory findings in the AML group (p > 0.05). Conclusions: Based on the results with ROC curve analysis, we propose to take into account the L/M ratio and the EAR from the parameters in the differential diagnosis between AA and AML in addition to previously reported parameters. Also, we recommend that the same features may be used to decide whether AML patients under observation are hospitalized or not.