Cylen Javidan-Nejad

A Pattern-based Approach to Assessment of Delayed Enhancement in Nonischemic Cardiomyopathy at MR Imaging

Although delayed contrast material-enhanced cardiac magnetic resonance (MR) imaging has traditionally been used to evaluate ischemic disease and myocardial viability, it is increasingly being used in the evaluation of nonischemic cardiomyopathies. Unlike myocardial infarction, which demonstrates subendocardial or transmural delayed contrast enhancement in a vascular distribution, nonischemic cardiomyopathies demonstrate enhancement that is not limited to a vascular territory. In combination with other cardiac MR imaging features, the location (subendocardial, transmural, subepicardial, or mesocardial) and pattern (patchy or diffuse) of abnormal delayed myocardial enhancement allow differentiation between ischemic (infarct-related) and nonischemic cardiomyopathies and, in cases of nonischemic cardiomyopathy, narrowing of the differential diagnosis. With use of a structured approach, delayed contrast-enhanced cardiac MR imaging can be helpful in the early detection and appropriate treatment of nonischemic cardiomyopathies.

Sensory functions of motile cilia and implication for bronchiectasis.

Cilia are specialized organelles that extend from the cell surface into the local environment. Cilia of the airway epithelia are motile to provide mucociliary clearance. On other cells, solitary cilia are specialized to detect chemical or mechanosensory signals. Sensory proteins in motile cilia have recently been identified that detect fluid flow, bitter taste and sex hormones. The relationship of these sensory functions in motile cilia to disease is now being revealed. An example are the polycystin-1 and polycystin-2 proteins that function as a flow sensor in kidney cilia and are mutated in autosomal dominant polycystic kidney disease (ADPKD). These polycystins are also expressed in motile cilia, potentially operating as sensors in the lung. Computed tomography studies from patients with ADPKD reveal evidence of bronchiectasis, suggesting polycystins are important in lung function. The motile cilia expression of this protein complex, as well as sensory channel TRPV4, bitter taste and sex hormones receptors, indicate that the cilia is wired to interpret environmental cues. Defective signaling of sensory proteins may result in a ciliopathy that includes lung disease.

MDCT of Trachea and Main Bronchi

Tracheobronchial imaging has undergone a major revolution since the advent of MDCT. The improved spatial and temporal resolution not only allows reformatting images that enhance the comprehension of disease before bronchoscopy or surgery, it has introduced newer techniques such as dynamic expiratory imaging to evaluate for tracheomalacia, which can be a subtle, but a confounding entity for patients and clinician alike. Tracheobronchial diseases can be arbitrarily divided into those that cause focal and diffuse narrowing and widening. Such groupings can help develop a practical approach in evaluating diseases of the central airways.

Stabilization of Disease after Targeted Therapy in a Thymic Carcinoma with KIT Mutation Detected by Clinical Next-Generation Sequencing

Precision medicine uses individually determined genomic information to guide treatment in cancer and other diseases. We have implemented a clinical genomics assay that uses targeted next-generation sequencing of 25 cancer-related genes to guide the use of targeted therapies in diverse malignancies. We report the case of a 55-year-old woman with a poorly differentiated squamous cell carcinoma of thymic origin, with disease progression after standard treatment. Targeted tumor sequencing revealed the presence of a KIT codon 579 deletion (p.D579del). This specific mutation has not previously been associated with thymic tumors, but has been reported in gastrointestinal stromal tumors and has been associated with response to imatinib. Imatinib therapy was instituted for and resulted in stabilization of disease. This case illustrates the potential of clinical next-generation sequencing to open unexpected avenues for treatment and thereby improve patient outcomes.

ACR Appropriateness Criteria Chronic Chest Pain—Low to Intermediate Probability of Coronary Artery Disease

Chronic chest pain can arise from a variety of etiologies. However, of those potential causes, the most life-threatening include cardiac disease. Chronic cardiac chest pain may be caused either by ischemia or atherosclerotic coronary artery disease or by other cardiac-related etiologies, such as pericardial disease. To consider in patients, especially those who are at low risk for coronary artery disease, are etiologies of chronic noncardiac chest pain. Noncardiac chest pain is most commonly related to gastroesophageal reflux disease or other esophageal diseases. Alternatively, it may be related to costochondritis, arthritic or degenerative diseases, old trauma, primary or metastatic tumors, or pleural disease. Rarely, noncardiac chest pain may be referred pain from organ systems below the diaphragm, such as the gallbladder. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® Acute Chest Pain—Suspected Pulmonary Embolism

Pulmonary embolism (PE) remains a common and important clinical condition that cannot be accurately diagnosed on the basis of signs, symptoms, and history alone. The diagnosis of PE has been facilitated by technical advancements and multidetector CT pulmonary angiography, which is the major diagnostic modality currently used. Ventilation and perfusion scans remain largely accurate and useful in certain settings. Lower-extremity ultrasound can substitute by demonstrating deep vein thrombosis; however, if negative, further studies to exclude PE are indicated. In all cases, correlation with the clinical status, particularly with risk factors, improves not only the accuracy of diagnostic imaging but also overall utilization. Other diagnostic tests have limited roles. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Accuracy of computed tomography findings in acute pericarditis

Background: Acute pericarditis is a close clinical mimic of pulmonary embolism (PE) in the emergency department, and thus many of these patients are evaluated with chest computed tomography (CT). Purpose: To study whether CT findings can be diagnostic of acute pericarditis. Material and Methods: Using the electronic medical record, we retrospectively identified 46 cases of acute pericarditis and 46 control patients with pericardial effusions due to volume overload, all of whom underwent CT examination. Cases were reviewed by two blinded academic thoracic radiologists. Results: The majority, 67%, of the pericarditis cases were evaluated with PE-protocol CTs. Pericardial thickening/enhancement was the most accurate single parameter for pericarditis, with sensitivity of 54–59% and specificity of 91–96%. Conclusion: CT findings, while not sensitive for pericarditis, are diagnostic, with few false-positives. Radiologists should be attentive to pericardial thickening or enhancement on CT studies done for chest pain, as they may be able to suggest pericarditis as an alternative diagnosis for the chest pain.

Imaging of Pregnancy-related Vascular Complications

Pregnancy results in substantial hemodynamic and prothrombotic changes that form the foundation for downstream vascular complications, both during pregnancy and in the postpartum period. In addition, several important risk factors, including older patient age, diabetes, and smoking, can increase the risk for vascular-related pregnancy complications. Because radiologists often play an important role in evaluation of the pregnant patient, understanding the pathophysiology of vascular-related complications in pregnancy and their imaging appearances is essential for diagnostic accuracy. The authors review relevant normal physiologic changes of pregnancy, pathophysiologic changes, and imaging features of vascular conditions that can manifest in conjunction with pregnancy. Particular attention is given to pertinent imaging information that radiologists should provide to referring clinicians to optimally affect the management of pregnant patients as well as women in the peripartum and postpartum stages. Among the complications discussed are preeclampsia; hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome; spontaneous coronary artery dissection; placental abruption; amniotic fluid embolism and acute pulmonary embolism; dural venous sinus thrombosis; ovarian vein thrombophlebitis; vasa previa; uterine arteriovenous malformations; heritable aortopathies; and hereditary hemorrhagic telangiectasia. To help radiologists avoid the use of unnecessary ionizing radiation in pregnancy, imaging examination selection and optimization are also reviewed. Radiologists should be familiar with the physiologic changes of pregnancy, radiation risks during gestation, and pregnancy-related vascular complications to improve imaging examination selection, diagnosis, and clinical management. ©RSNA, 2017.

Segmental analysis of congenital heart disease: putting the "puzzle" together with computed tomography.

Advances in surgical and medical treatment for congenital heart disease have resulted in greater life expectancy. As a result, there has been an increase in the utilization of cross-sectional imaging for diagnosis and management of complex congenital heart disease. This manuscript describes a morphological and sequential segmental approach to deciphering the code of complex congenital heart defects in cross-sectional imaging, mostly computed tomography. This manuscript will review approaches to differentiate types of transposition, the anatomic relationships of cardiac structures, and the application of these relationships in the description of complex congenital heart disease.

Feasibility of detecting myocardial ischemia using first-pass contrast MRI and regadenoson

Summary A single injection of regadenoson can be used instead of an adenosine infusion to produce coronary vasodilatation and demonstrate myocardial ischemia during firstpass perfusion cardiac MRI. Background Cardiac stress MR perfusion imaging requires an MRI compatible infusion pump for the administration of adenosine or a non-MRI compatible pump housed in the control room or beyond the 10-Gauss line. Regadenoson is a recently FDA-approved A2A receptor agonist that can be given intravenously in a single bolus. It has been shown to provide diagnostic information regarding myocardial ischemia on SPECT-MPI. Methods