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Takotsubo cardiomyopathy (TC) is an acute but reversible non-ischemic heart failure syndrome. It is characterized by a transient form of ventricular dysfunction typically manifesting as basal hyperkinesis with hypokinesia and ballooning of left ventricle mid-cavity and apex. Imaging helps in both diagnosis and follow up. Echocardiogram is the first-line modality to assess the typical contractile dysfunction in suspected patients with catheter angiography showing normal coronary arteries. Cardiac MRI is currently the modality of choice for the non-invasive initial assessment of TC and for follow up imaging. The current review focusses on historical background of TC, its pathophysiology, diagnostic work up and differential diagnosis and provides multimodality imaging work up of TC including role of echocardiogram, invasive catheterization, nuclear imaging, cardiac computed tomography and cardiac MRI including basic and advanced MRI sequences. • Takotsubo cardiomyopathy (TC) is reversible syndrome mimicking acute coronary syndrome. • TC is typically characterized by basal hyperkinesis and apical akinesis. • Echocardiography and catheter angiography are often first line modality. • Cardiac MRI is modality of choice for the non-invasive initial assessment. • Cardiac MRI provides comprehensive evaluation for initial diagnosis and follow up. [ABSTRACT FROM AUTHOR]

Objectives: Computed tomography pulmonary angiogram (CTPA) is one of the most commonly ordered and frequently overused tests. The purpose of this study was to evaluate the mean radiation dose to patients getting CTPA and to identify factors that are associated with higher dose. Material and Methods: This institutionally approved retrospective study included all patients who had a CTPA to rule out acute pulmonary embolism between 2016 and 2018 in a tertiary care center. Patient data (age, sex, body mass index [BMI], and patient location), CT scanner type, image reconstruction methodology, and radiation dose parameters (dose-length product [DLP]) were recorded. Effective dose estimates were obtained by multiplying DLP by conversion coefficient (0.014 mSv·mGy-1·cm-1). Multivariate logistic regression analysis was performed to determine the factors affecting the radiation dose. Results: There were 2342 patients (1099 men and 1243 women) with a mean age of 58.1 years (range 0.2-104.4 years) and BMI of 31.3 kg/m² (range 12-91.5 kg/m²). The mean effective radiation dose was 5.512 mSv (median - 4.27 mSv; range 0.1-43.0 mSv). Patient factors, including BMI >25 kg/m², male sex, age >18 years, and intensive care unit (ICU) location, were associated with significantly higher dose (P < 0.05). CT scanning using third generation dual-source scanner with model-based iterative reconstruction (IR) had significantly lower dose (mean: 4.90 mSv) versus single-source (64-slice) scanner with filtered back projection (mean: 9.29 mSv, P < 0.001). Conclusion: Patients with high BMI and ICU referrals are associated with high CT radiation dose. They are most likely to benefit by scanning on newer generation scanner using advance model-based IR techniques. [ABSTRACT FROM AUTHOR]

Simple Summary: Prior radiomic studies have addressed a two-class tumor classification problem (glioblastoma (GBM) versus primary CNS lymphoma (PCNSL) or GBM versus metastasis). However, this approach is prone to bias and excludes other common brain tumor types. We addressed a real-life clinical problem by including the three most common brain tumor types (GBM, PCNSL, and metastasis). We investigated two key issues using different MRI sequence combinations: performance variation based on tumor subregions (necrotic, enhancing, edema and combined enhancing, and necrotic masks), and performance metrics based on the chosen classifier model/feature selection combination. Our study provides evidence that radiomics-based three-class tumor differentiation is feasible, and that embedded models perform better than those with a priori feature selection. We found that T1 contrast enhanced is the single best sequence with comparable performance to that of multiparametric MRI, and model performance varies based on tumor subregion and the combination of model/feature selection methods. Prior radiomics studies have focused on two-class brain tumor classification, which limits generalizability. The performance of radiomics in differentiating the three most common malignant brain tumors (glioblastoma (GBM), primary central nervous system lymphoma (PCNSL), and metastatic disease) is assessed; factors affecting the model performance and usefulness of a single sequence versus multiparametric MRI (MP-MRI) remain largely unaddressed. This retrospective study included 253 patients (120 metastatic (lung and brain), 40 PCNSL, and 93 GBM). Radiomic features were extracted for whole a tumor mask (enhancing plus necrotic) and an edema mask (first pipeline), as well as for separate enhancing and necrotic and edema masks (second pipeline). Model performance was evaluated using MP-MRI, individual sequences, and the T1 contrast enhanced (T1-CE) sequence without the edema mask across 45 model/feature selection combinations. The second pipeline showed significantly high performance across all combinations (Brier score: 0.311–0.325). GBRM fit using the full feature set from the T1-CE sequence was the best model. The majority of the top models were built using a full feature set and inbuilt feature selection. No significant difference was seen between the top-performing models for MP-MRI (AUC 0.910) and T1-CE sequence with (AUC 0.908) and without edema masks (AUC 0.894). T1-CE is the single best sequence with comparable performance to that of multiparametric MRI (MP-MRI). Model performance varies based on tumor subregion and the combination of model/feature selection methods. [ABSTRACT FROM AUTHOR]

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state often characterized by altered mental state and is seen in various clinical settings. Although it is often reversible, it may result in long term sequelae. The typical and atypical neuroimaging findings seen in PRES have been previously well-described in the literature. However, the presence of other co-existing intracranial lesions along with PRES can occasionally confound the imaging findings and poses a diagnostic challenge. Herein, the authors report four cases of PRES with etiologically different co-existing intracranial lesions confounding the clinical and imaging manifestations. When presented with atypical imaging findings in PRES, the possibility of a co-existing intracranial pathology with superimposed imaging findings should be considered. • PRES is a well-recognized entity presenting with acute symptoms such as encephalopathy, headache, and visual disturbances. • PRES can be co-existing with other intracranial pathologies complicationg the neuroimaging picture • Differentiation of a PRES from co-existing pathology may be feasible and help guide appropriate therapy. • This case series presents four such cases where PRES was present along with other intracranial patholgies. [ABSTRACT FROM AUTHOR]