Importance of screening severe COVID-19 patients for IFN-λ1, IL-6 and anti-S1 IgG levels.

Cytokine storm is an important cause of death in COVID-19 patients. A recent clinical study showed that administration of recombinant interferon lambda 1 (IFN-λ1 or IL-29) may prevent severe COVID-19. On the other hand, IL-6 has been associated as a prognostic marker of worsening for COVID-19 patients. The objective of this study is to screen IFN-λ1, IL-6 and antibody levels in consecutive serum sample sets of COVID-19 patients. A total of 365 serum samples collected from 208 hospitalized COVID-19 patients were analyzed for IFN-λ1 and IL-6 levels as well as SARS-CoV-2 neutralizing antibodies and anti-S1 IgG antibodies. Analyses of serum samples for cytokine levels showed that IFN-λ1 (>8 pg/mL) and IL-6 (>2 pg/mL) were detected in approximately 64% and 21% patients, respectively. A decrement in IFN-λ1 levels and IL-6 levels above 35 pg/mL can be sign of clinical severity and upcoming dead. An increment in IL-6 levels wasn't detected in every COVID-19 patient but a decrement in IL-6 levels was related to clinical improvement. Importantly, the detection of IFN-λ1 level together with an increase in anti-S1 IgG antibody response were observed in clinically improved patients. Screening severe COVID-19 patients for IFN-λ1, IL-6, and anti-S1 IgG antibody levels during their hospital stay especially in intensive care units may be beneficial to monitor the clinical status and management of treatment strategies. Importantly, detection of IFN-λ1 together with protective IgG antibody response can be an indication of clinical improvement in severe COVID-19 patients and these patients may be discharged from the hospital soon.

Prespecialist perceptions of three-dimensional heart models in anatomical education.

PURPOSE: This article aims to discuss the use of three-dimensional (3D) printed models of vascular variation cases as an educational tool for undergraduate and postgraduate anatomy students. METHODS: This advanced study involved ten anatomy assistants who were provided with five distinct cases of congenital cardiovascular variations, each accompanied by a computed tomography angiography (CT-A) and 1:1 solid model format. The residents were asked to generate perceptions for both formats and then compare these perceptions based on identifying the variation, defining the structural features, and evaluating relevant educational perspectives. RESULTS: The vascular origin measurement values compared to the statistically evaluated real values of the related cases showed that models were 1:1 identical copies. Qualitative assessment feedback from five stations supported the usefulness of 3D models as educational tools for organ anatomy, simulation of variational structures, and overall medical education and anatomy training. Models showcasing different anatomical variations such as aortic arch with Type 2 pattern, a right-sided aortic arch with Type 2 pattern, an aberrant right subclavian artery, arteria lusoria in thorax, and a left coronary artery originating from pulmonary trunk in an Alcapa type pattern allow for better analysis due to their complex anatomies, thus optimizing the study of variation-specific anatomy. The perception level in the 3D model contained higher points in all of the nine parameters, namely identification of cardiovascular variations, defining the vessel with anomaly, aortic arch branch count and appearance order, feasibility of using it in peers and student education. 3D models received a score 9.1 points, while CT-A images were rated at 4.8 out of 10. CONCLUSION: 3D printed anatomical models of variational cardiovascular anatomy serve as essential components of anatomy training and postgraduate clinical perception by granting demonstrative feedback and a superior comprehension of the visuospatial relationship between the anatomical structures.

Cardiac Assessment in Children with MIS-C: Late Magnetic Resonance Imaging Features.

Multisystem Inflammatory Syndrome (MIS-C) is a new entity that emerges 2-4 weeks after the SARS-CoV-2 infection in children. MIS-C can affect all systems, the most severe of which is cardiac involvement. The duration of the cardiac symptoms is still uncertain and may be persistent or prolonged. The American College of Rheumatology Clinical Guidelines recommends cardiac magnetic resonance imaging (MRI) 2-6 months after the diagnosis of MIS-C in patients presenting with significant transient left ventricular (LV) dysfunction in the acute phase of illness (LV ejection fraction 50%) or persistent LV dysfunction. There are a few studies investigating cardiac MRI findings in MIS-C patients. In this study, we aimed to evaluate cardiac MRI findings, at the earliest 3 months after diagnosis, and compare these findings with the echocardiograms in children with MIS-C. A retrospective study including 34 MIS-C patients was conducted at a tertiary-level University Hospital between June 2020 and July 2021. Centers for Disease Control and Prevention criteria were used in the diagnosis of MIS-C. Cardiac MRI was performed at least 3 months after MIS-C diagnosis. The study included 17 (50%) boys and 17 (50%) girls with a mean age of 9.31 ± 4.72 years. Initial echocardiographic evaluation revealed cardiac abnormality in 13 (38.2) patients; 4 (11.8%) pericardial effusion, 4 (11.8%) left ventricular ejection fraction (LVEF) < 55%, and 5 (14.7%) coronary artery dilatation. Echocardiography showed normal LV systolic function in all patients during follow-up; coronary dilatation persisted in 2 of 5 (40%) patients at the 6th-month visit. Cardiac MRI was performed in 31 (91.2%) patients, and myocardial hyperemia was not detected in any patients (T1 relaxation time was < 1044 ms in all children). However, 9 (29%) patients' MRI showed isolated elevated T2 levels, and 19 (61.3%) revealed at least one of the following findings: pericardial effusion, right ventricular dysfunction, or LVEF abnormality. In patients with MIS-C, a high rate of cardiac involvement, particularly pericardial effusion was determined by cardiac MRI performed at the earliest 2-6 months after diagnosis. Even if echocardiography does not reveal any abnormality in the initial phase, cardiac MRI should be suggested in MIS-C patients in the late period. This is the first study reporting cardiac MRI findings in the late period of MIS-C patients.

Comparison of chest computed tomography and 3-T magnetic resonance imaging results in patients with common variable immunodeficiency.

BACKGROUND: Patients with common variable immunodeficiency (CVID) have an increased incidence of pulmonary infections and require frequent follow-up computed tomography (CT) scans. PURPOSE: To evaluate the diagnostic performance of 3-T magnetic resonance imaging (MRI) in patients with CVID. MATERIAL AND METHODS: In this prospective study, 3-T MRI was performed in 20 patients with CVID. The patients were imaged with CT and MRI scans on the same day. The MRI protocol included a T2-weighted HASTE sequence (TR=1400 ms, TE=95 ms, slice thickness (ST)=3 mm), T2-weighted BLADE sequence (TR=5379 ms, TE=100 ms, ST=3 mm), and 3D VIBE sequence (TR=3.9 ms, TE=1.32 ms, ST=3 mm). Mediastinal and parenchymal changes were compared. A modified Bhalla scoring system was used in the evaluation of CT and MRI scans. RESULTS: A total of 17 (85%) patients had parenchymal abnormalities identified by CT or MRI. Similar findings were detected with CT and MRI in the assessment of the severity of bronchiectasis (P=0.083), bronchial wall thickening (P=0.157), and mucus plugging (P=0.250). Consolidations were detected with both modalities in all patients. There was excellent concordance between the two modalities in the evaluation of nodules >5 mm (nodule size 5-10 mm, P=0.317; nodule size >10 mm, P=1). However, MRI failed to detect most of the small nodules (<5 mm). CONCLUSION: 3-T MRI detected mediastinal and parenchymal alterations in patients with CVID and provided findings that correlated well with CT. Despite a few limitations, MRI is a well-suited radiation-free technique for patients requiring longitudinal imaging.

The outcome of peripartum cardiomyopathy patients-single center experience.

OBJECTIVE: Peripartum cardiomyopathy (PPCM) diagnosis made by excluding identifiable causes of heart failure (HF) and occurs end of the pregnancy or during the postpartum period of five months. It presents a clinical HF spectrum with left ventricular systolic dysfunction. BACKGROUND: The purpose of this study is to retrospectively evaluate the clinical characteristics, cardiac magnetic resonance (CMR) imaging features, and end-points consisting of left ventricle recovery, left ventricular assist device implantation, heart transplantation, and all-cause mortality. METHOD: Outpatient HF records between 2008 to 2021 were screened. Thirty-seven patients were defined as PPCM. Twenty-five patients had CMR evaluation at the time of diagnosis, and six patients were re-evaluated with CMR. RESULTS: The mean age was 30.5 ± 5.6 years, and the mean LVEF was 28.2% ± 6.7%. In 13(35.7%) patients, LVEF recovered during the follow-up course. The median recovery time was 281(IQR [78-358]) days. LVEF on CMR was 35.3 ± 10.5, and three patients exhibited late gadolinium enhancement(LGE) patterns. Sub-endocardial and mid-wall uptake pattern types were detected. 18(75%) patients met the Petersen left ventricle non-compaction cardiomyopathy(LVNC) criteria. Patients with NC/C ratio lower than 2.3 had lower LVEDVi and LVESVi (124.9 ± 35.4, 86.4 ± 7.5, p = .003; 86.8 ± 34.6, 52.6 ± 7.6, p = .006), respectively. The median follow-up time was 2129 (IQR [911-2634]) days. The primary endpoint-free 1-year survival was 88.9% (event rate 11.1%), and 5-year survival was 75.7% (event rate 24.3%). CONCLUSION: In a retrospective cohort of PPCM patients, 35.7% of patients' LVEF recovered, and the primary end-point of free-5-year survival was 75%. Twenty-five patients were assessed with CMR; three of four met the Petersen CMR-derived LVNC at initial evaluation.

Comparison of Brock University, Mayo Clinic and Herder models for pretest probability of cancer in solid pulmonary nodules.

OBJECTIVE: Risk analysis models, which are used in the diagnostic algorithm of incidental pulmonary nodules, are based on patient data from developed countries. Mayo Clinic, Brock University and Herder are among the most known models. We aim to compare the reliability of these models in patients with indeterminate solid nodules and to investigate the contribution of the predictors used to the model. METHODS: We analysed 305 patients who performed transthoracic needle biopsy and positron emission tomography/computed tomography for solid nodules, retrospectively. For all three models, the malignancy risk probabilities of patients were calculated, and patients were classified as low (<5%), moderate (60%) and high (<60%) risk groups. Later, the malignancy rates of each model in three different risk groups were compared within each other and among the models. RESULTS: The malignancy rate is 73% in 305 patients. In the Mayo Clinic and Herder models, the difference in the low-, medium- and high-risk groups is significant (p < 0.001). In the medium-risk group, the rate of malignancy is 96.8% in the Brock model. In the high-risk group, the rate of malignancy in Herder is 88.3% and the rate of malignancy in Mayo Clinic is 28.8%. The optimal cutoff values for the Mayo Clinic, Brock University, and Herder were 29.6, 13.4 and 70 (AUC, respectively; 0.71, 0.67 and 0.73). Age, smoking, gender, size, emphysema and spiculation increase the likelihood of malignancy. CONCLUSION: Close results were obtained in all three models. In the high-risk group, the Herder model has the highest reliability rate (odds ratio 3.3, confidence interval [1.1, 10.2]). Upper lobe predilection is not a reliable predictor.

Characteristics and long-term survival of patients with left ventricular non-compaction cardiomyopathy.

AIMS: Left ventricular non-compaction cardiomyopathy (LVNC) is a poorly understood entity resulting in heart failure. Whether it is a distinct form of cardiomyopathy or an anatomical phenotype is a subject of discussion. The current diagnosis is based on morphologic findings by comparing the compacted to non-compacted myocardium. The study aimed to compare demographic and prognostic variables of patients with dilated cardiomyopathy (DCM) and LVNC. Emphasis was given to cardiac magnetic resonance (CMR) imaging analysis. Data on survival were also assessed. METHODS AND RESULTS: We retrospectively evaluated the characteristics and outcomes of 262 non-ischaemic cardiomyopathy patients with LVNC and DCM phenotypes. Petersen's CMR criteria of non-compacted to the compacted myocardial ratio 2.3 were used to diagnose LVNC. The primary endpoint was a composite endpoint of major adverse cardiovascular events comprising cardiovascular-related death, left ventricular assisted device implantation, or heart transplantation. A total of 262 patients with CMR data were included in the study. One hundred fifty-five patients who fulfilled CMR criteria were diagnosed as LVNC. CMR findings revealed that LVNC patients had higher left ventricular end-diastolic (137.2 ± 51.6, 116.8 ± 44.6, P = 0.002) and systolic volume index (98.4 ± 49.5, 85.9 ± 42.7, P = 0.049). Cardiac haemodynamics, cardiac output (5.61 ± 2.03, 4.96 ± 1.83; P = 0.010), stroke volume (73.9 ± 28.8, 65.1 ± 25.1; P = 0.013), and cardiac index (2.85 ± 1.0, 2.37 ± 0.72; P < 0.0001), were higher in LVNC patients. Of all the 249 patients, 102 (40.9%) patients demonstrated late gadolinium enhancement (LGE). According to Petersen's criteria, the Kaplan-Meier survival outcome did not reveal significant differences (hazard ratio [HR]: 1.53, 95% confidence interval [CI]: [0.89-2.63], P = 0.11). The presence or pattern of LGE did not show significant importance for endpoint-free survival. Most of the sub-epicardial LGE pattern was found in LVNC patients (94.4%). When receiver operator characteristics analysis was applied to NC/C ratio to discriminate the primary endpoint, a higher NC/C ratio of 2.57 was associated with adverse events (HR: 1.90, 95% CI: [1.12-3.24], P = 0.016). CONCLUSIONS: Our study questions the criteria being used for the diagnosis of LVNC. Further evaluation of CMR variables and association of these findings with demographic variables and survival is mandatory.

PDL-1 Expression and Survival in Metastatic Non-small Cell Lung Cancer Patients Who Received Chemotherapy as First-Line Treatment.

OBJECTIVE: To show the effect of programmed cell death protein-1ligand (PDL-1) level on survival times in patients with metastatic non-small cell lung cancer (mNSCLC) receiving chemotherapy, to determine the relationship between PDL-1 level, neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR). MATERIAL AND METHODS: The data of 158 patients who received chemotherapy for mNSCLC were evaluated retrospectively. Clinical and demographic data, PDL-1 expression levels and follow-up periods of the patients were recorded. The patients were divided into 2 groups according to PDL-1 levels. RESULTS: In all patients, progression free survival (PFS) was 5.6 months and overall survival (OS) was 18.8 months. Patients with low PDL-1 had a longer PFS than patients with high PDL-1 (p:0.038). In the gemcitabine and taxane groups, patients with low PDL-1 had a longer PFS than patients with high PDL-1 (p:0.047). There was a significant correlation between NLR and PDL-1 levels. In the groups with high PDL-1, patients with low NLR levels had higher OS than patients with high NLR level (p:0.043). Also, there was a significant difference between the OS patients with low and high PLR levels (p:0.520). CONCLUSION: In patients with mNSCLC whose PDL-1 levels and NLR levels are low, immunogenic chemotherapies such as gemcitabine and taxane can be tried as an alternative treatment.

New-Onset Hypercalcemia After Renal Transplant: An Infectious Etiology Beyond Persistent Hyperparathyroidism.

Pneumocystis jirovecii pneumonia is an opportunistic infection in kidney transplant recipients. It may be complicated by hypercalcemia. Here, we discuss a 59-year-old man who presented with respiratory symptoms and hypercalcemia. He had undergone a deceased donor kidney transplant 2 years previously. The patient had persistent hyperparathyroidism, but his serum calcium level was normal. At the time of admission, his serum calcium level had increased and his parathyroid hormone level was suppressed. He was diagnosed with Pneumocystis jirovecii pneumonia. Serum calcium and parathyroid hormone levels returned to baseline values after treatment. Pneumocystis jirovecii pneumonia is an important infection that can present with hypercalcemia among kidney transplant recipients.

Quantitative CT in mortality prediction in pulmonary fibrosis with or without emphysema.

AIM: We aimed to evaluate the quantitative CT analysis of patients with CPFE in comparison with IPF and emphysema. METHODS: Patients with CPFE(n:36), IPF(n:38) and emphysema(n:32) were retrospectively included in the study with the approval of the ethics committee. RESULTS: There was a positive correlation between total lung volume and FVC%, TLCO% and 6 MWT, and negative correlation between mMRC and mortality. Negative correlation was found between right, left lung density and FVC%, TLCO% and 6 MWT, and positive correlation between mortality. Also, total lung volume, right and left lung densities were significant in predicting mortality and cut-off values are ≤3831,> -778 and> -775, respectively (p = 0.040, 0.020, 0.013). CONCLUSION: Quantitative CT are guiding in predicting mortality of the disease.

Prevalence of Incidental Gynecomastia by Chest Computed Tomography in Patients with a Prediagnosis of COVID-19 Pneumonia.

OBJECTIVE: In this study, we aimed to determine the prevalence of gynecomastia by evaluating computed tomography (CT) images of male patients who were admitted to our hospital during the coronavirus disease-2019 (COVID-19) pandemic. MATERIALS AND METHODS: This study included a total of 1,877 patients who underwent chest CT for prediagnosis of COVID-19 pneumonia between March 15th and May 15th, 2020. All images were evaluated for the presence of gynecomastia. Gynecomastia patterns were evaluated according to morphological features, and diagnoses were made by measuring the largest glandular tissue diameter. Statistical analysis was performed with IBM SPSS software version 25.0. RESULTS: The prevalence of gynecomastia was 32.3%. In terms of pattern, 22% were nodular, 57% were dendritic, and 21% were diffuse glandular gynecomastia. A significant correlation was found between age and gynecomastia pattern (p<0.001). The incidence of nodular, dendritic, and diffuse glandular gynecomastia increased with advancing age. A significant difference was found in the analysis of the correlation between age groups and glandular tissue diameters (p<0.001). With an increase in glandular tissue diameter, the gynecomastia pattern changed from a nodular to a diffuse glandular pattern. CONCLUSION: In our study, gynecomastia diagnosis was made through axial CT images. Although CT should not replace mammography and ultrasonography for clinical diagnosis of gynecomastia, chest CT scans can be used to evaluate patients with suspected gynecomastia.

Comparison of typical and atypical computed tomography patterns regarding reversibility and fibrosis in pulmonary sarcoidosis.

PURPOSE: This study aims to investigate whether there is a significant difference between typical and atypical parenchymal patterns in the development of fibrosis, which is the most crucial factor affecting morbidity in pulmonary sarcoidosis. METHODS: In our hospital, 145 cases with Siltzbach Types 2 and 3 sarcoidoses diagnosed by clinical, radiological, and histopathologic were retrospectively investigated. Perilymphatic nodules, accompanying mosaic attenuation, and interlobular septal thickening and central peribronchovascular bunch-like thickening on high-resolution computed tomography were assessed as typical. Solid nodules, galaxy finding, consolidation, ground-glass opacity, isolated mosaic attenuation, and interlobular septal thickening, and pleural fluid were accepted as atypical findings. Findings indicating fibrosis were fine and rough reticular opacity, traction bronchiectasis, volume loss, and cystic changes. For the analysis of variables, SPSS 25.0 program was used. RESULTS: Ten (16%) of the 61 cases with typical findings and 16 (19%) of the 84 with atypical findings developed fibrosis (P = 0.827). The mean age of cases with fibrosis was higher. With the cut-off of 50 years, sensitivity was 61.5%, and specificity was 68.9%. The highest fibrosis rate was in cases with ground glass pattern (n = 7/17), whereas higher reversibility rates were in those with miliary pattern (n = 9/12) and galaxy sign (n = 5/6). CONCLUSION: The incidence of fibrosis is higher in the atypical group with no significant difference. The incidence of fibrosis differs in each atypical pattern, being highest in ground-glass opacity and lowest in the miliary pattern.

The novel coronavirus pneumonia (COVID-19): a pictorial review of chest CT features.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first reported in Wuhan, China. The infection rapidly spread to more than 200 countries around the world. The clinical presentation of the disease may vary from mild illness to severe pneumonia such as acute respiratory distress syndrome (ARDS). The chest computed tomography (CT) has an important complementary role in diagnosis of the disease. The predominant CT findings of the disease are ground glass opacities and consolidations located in subpleural areas of lower lobes. Widespread ground-glass opacities, consolidation, air bronchograms, central involvement of lung parenchyma, mediastinal lymphadenopathy are more common in patients with the severe form of the disease. CT imaging also guides in differentiation of alternative diagnosis or in assessment of associated pulmonary embolism during the course of the disease. In this pictorial review we aim to review the CT features of COVID-19 pneumonia and mention the changes throughout the disease process.

Correlation of liver-to-spleen ratio, lung CT scores, clinical, and laboratory findings of COVID-19 patients with two consecutive CT scans.

PURPOSE: Given the lack of information about abdominal imaging findings and correlation with clinical features of COVID-19, we aimed to evaluate the changes in hepatic attenuation during the course of disease. Our aim was to correlate the liver-to-spleen ratio (L/S), clinical, laboratory findings, and lung CT scores of patients with COVID-19 who had two consecutive chest CTs. METHODS: A retrospective search was performed between March 1, 2020 and April 26, 2020 to identify patients who had positive RT-PCR tests and two unenhanced chest CTs. Scans that were obtained at hospital admission and follow-up were reviewed to assess L/S and lung CT scores. Patients were divided into two groups based on lung CT scores (non-progressive vs progressive). Patient demographics, laboratory findings, length of hospital stay, and survival were noted from electronic medical records. RESULTS: Twenty patients in the progressive group and 7 patients in the non-progressive group were identified. The mean L/S of the progressive group (1.13 ± 0.3) was lower than that of the non-progressive group (1.21 ± 0.29) at hospital admission but there was no significant difference between the two groups (p = 0.547). L/S at follow-up was significantly different between the groups as the mean L/S values of the progressive and non-progressive groups were 1.02 ± 0.23 and 1.25 ± 0.29, respectively (p = 0.009). L/S was negatively correlated with AST and ALT (r = - 0.46, p = 0.016 and r = - 0.534, p = 0.004, respectively). There were significant differences between the two groups in terms of WBC, neutrophil, lymphocyte, monocyte, and platelet counts that were obtained at hospital admission. Length of hospital stay was significantly longer in patients in the progressive group (p = 0.035). CONCLUSIONS: Decrease in L/S may be observed in patients with elevated lung CT scores at follow-up. WBC, neutrophil, lymphocyte, monocyte, and platelet counts at hospital admission may predict the progression of COVID-19.

Histogram Analysis of ADC Maps for Differentiating Brain Metastases From Different Histological Types of Lung Cancers.

PURPOSE: Our study aimed to investigate the role of histogram analysis derived from apparent diffusion coefficient (ADC) maps in brain metastases (BMs) from lung cancer for differentiating histological subtype. METHODS: A total of 61 BMs (45 non-small cell lung cancer [NSCLC] comprising 32 adenocarcinoma [AC], 13 squamous cell carcinoma [SCC], and 16 small-cell lung cancer [SCLC]) in 50 patients with histopathologically confirmed lung cancer were retrospectively included in this study. Pretreatment cranial diffusion-weighted imaging was performed, and the corresponding ADC maps were generated. Regions of interest were drawn on solid components of the BM on all slices of the ADC maps to obtain parameters, including ADCmax, ADCmean, ADCmin, ADCmedian, ADCrange, skewness, kurtosis, entropy, ADC10, ADC25, ADC75, and ADC90. Apparent diffusion coefficient histogram parameters were compared among histological type groups. Kruskal-Wallis, Mann-Whitney U, chi-square tests, and receiver-operating characteristic (ROC) curve were used for statistical assessment. RESULTS: ADCmin, ADC10, and ADC25 were found to be significantly different among AC, SCC, and SCLC groups; these parameters were higher for AC group, moderate for SCC group, and significantly lower for SCLC group. Skewness and kurtosis were not significantly different among all groups. The ROC analysis for differentiating BMs of NSCLC from SCLC showed that ADC25 achieved the highest area under the curve at 0.922 with 93.02% sensitivity and 81.25% specificity. CONCLUSION: Apparent diffusion coefficient histogram analysis of BMs from lung cancer has significant prognostic value in differentiating histological subtypes of lung cancer.

Atypical chest CT findings of COVID-19 pneumonia: a pictorial review.

Coronavirus disease 2019 (COVID-19) first emerged in China and rapidly spread in the world causing a pandemic. Chest computed tomography (CT) continues to play an important role in the diagnosis and follow-up of the disease due to shortcomings of the real-time reverse transcription-polymerase chain reaction test, which is the gold standard in the diagnosis of this disease. Typical chest CT findings of COVID-19 pneumonia have been widely reported in the literature. However, atypical findings such as central involvement, peribronchovascular involvement, isolated upper lobe involvement, nodular involvement, lobar consolidation, solitary involvement, pleural and pericardial fluid, and subpleural sparing can also be seen. Knowing these atypical findings is important to avoid misdiagnosis. This review summarizes the atypical findings that can be seen in the course of the disease and may be confused with other diseases.

Diagnostic role of apparent diffusion coefficient combined with intratumoral susceptibility signals in differentiating high-grade gliomas from brain metastases.

OBJECTIVE: The aim of this study was to assess whether tumoral and peritumoral apparent diffusion coefficient values and intratumoral susceptibility signals on susceptibility-weighted imaging could distinguish between high-grade gliomas and brain metastases, and to investigate their associations with the Ki-67 proliferation index. MATERIALS AND METHODS: Fifty-seven patients with pathologically confirmed diagnoses of either high-grade glioma or brain metastasis were enrolled in this study (23 with high-grade gliomas and 34 with brain metastases). The minimum and mean apparent diffusion coefficients in the enhancing tumoral region (ADCmin and ADCmean) and the minimum apparent diffusion coefficient in the peritumoral region (ADCedema) were measured from apparent diffusion coefficient maps, and intratumoral susceptibility signal grades acquired by susceptibility-weighted imaging were calculated. Ki-67 proliferation index values were obtained from the hospital database. These parameters were evaluated using the Mann-Whitney U test, independent-sample t-test, Spearman correlation analysis, receiver operating characteristic curve, and logistic regression analyses. RESULTS: ADCmean, ADCmin values, and intratumoral susceptibility signal grades in brain metastases were significantly lower than those in high-grade gliomas (all p < 0.05). Ki-67 proliferation index values showed significant correlations with ADCmean, ADCmin, and intratumoral susceptibility signal grade in brain metastases (all p < 0.05), but no correlation was found in high-grade gliomas (all p > 0.05). According to receiver operating characteristic curve analysis, ADCmean achieved the highest diagnostic performance for discriminating high-grade gliomas from brain metastases. Furthermore, the combination of tumoral apparent diffusion coefficient parameters with intratumoral susceptibility signal grade provided a higher area under the curve than univariate parameters. CONCLUSION: The combination of tumoral apparent diffusion coefficient with intratumoral susceptibility signal grade can offer better diagnostic performances for differential diagnosis. Apparent diffusion coefficient and intratumoral susceptibility signal may reflect cellular proliferative activity in brain metastases, but not in high-grade gliomas.

CT imaging features of COVID-19 pneumonia: initial experience from Turkey.

PURPOSE: We aimed to demonstrate the computed tomography (CT) findings observed at the initial presentation of coronavirus disease 2019 (COVID-19) pneumonia and reveal the most frequent infiltration and distribution patterns of the disease. METHODS: One hundred and eighty-five patients (87 men, 98 women; mean age, 48.7 years), who underwent RT-PCR sampling and high-resolution CT examination in our hospital between March 15, 2020, and April 15, 2020, and got a definitive diagnosis of COVID-19 disease via initial or follow-up RT-PCR test, were included in the study. We comprehensively analyzed the most common and relatively rare CT imaging features (e.g., distribution pattern, density of the lesions, additional CT signs) in patients diagnosed with COVID-19 pneumonia. RESULTS: Thirty-eight patients (20.6%) had no evidence of pneumonia on their initial high-resolution CT images. Among 147 patients (79.4%) who had parenchymal infiltration consistent with pneumonia, 10 (6.8%) had a negative baseline RT-PCR test, and positivity was detected as a result of repeated tests. Most of the patients had multifocal (89.1%) and bilateral (86.4%) lesions. The most common location, right lower lobe, was affected in 87.8% of the patients. Lesions were distributed predominantly at peripheral (87.1%) and posterior (46.3%) areas of lung parenchyma. Most of the patients had pure ground glass opacity (GGO) (82.3%) followed by GGO with consolidation (32.7%) and crazy paving pattern (21.8%). Pure consolidation, solid nodules, halo sign, reverse halo sign, vascular enlargement, subpleural line, air-bronchogram, and bronchiectasis were the other findings observed in at least 15% of the cases. Halo sign, acinar nodules, air-bubble sign, pleural thickening and effusion, mediastinal and/or hilar lymphadenopathy were seen rarely (2%-12.9%). Pericardial effusion, pneumothorax, cavitation, and tree-in-bud pattern were not detected in our study group. CONCLUSION: Multifocal and bilateral GGO infiltration predominantly distributed in peripheral, posterior, and lower lung areas was the most common infiltration pattern.

Diagnostic success of transthoracic needle biopsy and PET-CT for 1 to 2 cm solid indeterminate pulmonary nodules.

OBJECTIVES: Among the nodule types, the most controversial group are indeterminate solid nodules from 1 to 2 cm in size with the first choice being transthoracic needle biopsy (TTNB) or positron emission tomography (PET-CT) or both methods together. However, no single diagnostic algorithm could be applied to all cases. This research discusses the diagnostic success of PET-CT and TTNB. MATERIALS AND METHODS: 407 Patients who referred to our hospital for any reason, with solid nodules with the size from 1 to 2 cmincidentally identified on the thoracic CT tests were investigated. Among the patients who underwent biopsy, 312 cases had PET-CT, and maximum SUV (SUVmax) values of the nodules were examined. Values of ≥2.5 were accepted as hypermetabolic. RESULTS: The mean age of the patients was 61 ± 10.8 years. 84 patients were female (20.6%) and 323 were male (79.4%). For TTNB; sensitivity, specificity and accuracy rates of all cases, who were correctly diagnosed, were 76.9%, 83.3% and 78.9%, respectively (P < .001). The 2.5 SUVmax cutoff value had sensitivity of 91%, specificity of 35.6%, accuracy of 75% (P = .034). The cutoff value of 49 years of age, nodule size of 16.4 mm, gender and 2.5 SUVmax value had high accuracy for benign-malignant differentiation. No statistically significant difference was found in the upper lobe localization of nodule. CONCLUSION: A positive result from TTNB is a reliable finding; however, a negative result is not definitive. The high negative predictive value of PET-CT is effective in preventing the unnecessary biopsies and surgical procedures.