John P. Lichtenberger

Multimodality imaging for characterization, classification, and staging of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is the most common primary malignancy of the pleura and is associated with asbestos exposure in approximately 80% of patients. The patient prognosis is poor, with a median survival of 9-17 months after diagnosis. However, improved survival and decreased morbidity and mortality have been demonstrated when the diagnosis is made in the early stages of disease and specific treatment strategies are implemented. A staging system that focuses on the extent of primary tumor (T), lymph node involvement (N), and metastatic disease (M) has been devised by the International Mesothelioma Interest Group and emphasizes factors related to overall survival. Radiologists should recognize the manifestations of MPM across multiple imaging modalities, translate these findings into the updated staging system, and understand the effects of appropriate staging on treatment and survival. Computed tomography (CT) remains the primary imaging modality used to evaluate MPM and efficiently demonstrates the extent of primary tumor, intrathoracic lymphadenopathy, and extrathoracic spread. However, additional imaging modalities, such as magnetic resonance (MR) imaging of the thorax and positron emission tomography (PET)/CT with fluorodeoxyglucose, have emerged in recent years and are complementary to CT for disease staging and evaluation of patients with MPM. Thoracic MR imaging is particularly useful for identifying invasion of the chest wall, mediastinum, and diaphragm, and PET/CT can accurately demonstrate intrathoracic and extrathoracic lymphadenopathy and metastatic disease.

Diffuse pulmonary hemorrhage: clues to the diagnosis.

Diffuse pulmonary hemorrhage (DPH) refers to an uncommon but significant condition of bleeding into the alveolar space. Anemia and hemoptysis are important clinical features, but they may be absent. Although the radiographic and computed tomography findings are often varied and nonspecific, the imaging manifestations of pulmonary hemorrhage and the associated findings in the thorax often provide important diagnostic information that may lead to a specific diagnosis. DPH significantly influences patient management and has important prognostic implications. This review article explores the imaging findings in DPH and its differential diagnosis, highlighting important clues to this diagnosis and to its underlying etiology. DPH is an uncommon condition characterized by bleeding into the alveolar space that, when recognized on imaging, provides important diagnostic and prognostic information.

What a Differential a Virus Makes: A Practical Approach to Thoracic Imaging Findings in the Context of HIV Infection??? Part 1, Pulmonary Findings

OBJECTIVE The Centers for Disease Control and Prevention reported more than one million people with HIV infection in the United States in 2006, an increase of 11% over 3 years. Worldwide, nearly 34 million people are infected with HIV. Pulmonary disease accounts for 30-40% of acute hospitalizations of HIV-infected patients, underscoring the importance of understanding the pulmonary manifestations in this population. When presented with a chest radiograph or CT image of a patient with the clinical history of HIV infection, one approach is to start by identifying and categorizing key imaging findings. In some instances, the key findings may be further subcategorized to narrow the differential diagnosis, such as distinguishing between perilymphatic distribution and the random distribution of micronodules. The differential diagnosis of these key imaging findings can also be further refined by incorporating clinical data, such as patient demographics, CD4 count, and presenting symptoms. Finally, the change of thoracic disease and clinical status in response to treatment provides important diagnostic information. The purpose of this article is to discuss pulmonary findings in patients with HIV. CONCLUSION By developing a systematic and practical approach to key pulmonary imaging findings in HIV-infected patients, radiologists can generate clinically relevant and succinct differential diagnoses and thereby improve patient care.

Imaging Evaluation of Malignant Chest Wall Neoplasms

Neoplasms of the chest wall are uncommon lesions that represent approximately 5% of all thoracic malignancies. These tumors comprise a heterogeneous group of neoplasms that may arise from osseous structures or soft tissues, and they may be malignant or benign. More than 50% of chest wall neoplasms are malignancies and include tumors that may arise as primary malignancies or secondarily involve the chest wall by way of direct invasion or metastasis from intrathoracic or extrathoracic neoplasms. Although 20% of chest wall tumors may be detected at chest radiography, chest wall malignancies are best evaluated with cross-sectional imaging, principally multidetector computed tomography (CT) and magnetic resonance (MR) imaging, each of which has distinct strengths and limitations. Multidetector CT is optimal for depicting bone, muscle, and vascular structures, whereas MR imaging renders superior soft-tissue contrast and spatial resolution and is better for delineating the full extent of disease. Fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT is not routinely performed to evaluate chest wall malignancies. The primary functions of PET/CT in this setting include staging of disease, evaluation of treatment response, and detection of recurrent disease. Ultrasonography has a limited role in the evaluation and characterization of superficial chest wall lesions; however, it can be used to guide biopsy and has been shown to depict chest wall invasion by lung cancer more accurately than CT. It is important that radiologists be able to identify the key multidetector CT and MR imaging features that can be used to differentiate malignant from benign chest lesions, suggest specific histologic tumor types, and ultimately guide patient treatment. (©)RSNA, 2016.

Multimodality imaging of cardiothoracic lymphoma

Lymphoma is the most common hematologic malignancy and represents approximately 5.3% of all cancers. The World Health Organization published a revised classification scheme in 2008 that groups lymphomas by cell type and molecular, cytogenetic, and phenotypic characteristics. Most lymphomas affect the thorax at some stage during the course of the disease. Affected structures within the chest may include the lungs, mediastinum, pleura, and chest wall, and lymphomas may originate from these sites as primary malignancies or secondarily involve these structures after arising from other intrathoracic or extrathoracic sources. Pulmonary lymphomas are classified into one of four types: primary pulmonary lymphoma, secondary pulmonary lymphoma, acquired immunodeficiency syndrome-related lymphoma, and post-transplantation lymphoproliferative disorders. Although pulmonary lymphomas may produce a myriad of diverse findings within the lungs, specific individual features or combinations of features can be used, in combination with secondary manifestations of the disease such as involvement of the mediastinum, pleura, and chest wall, to narrow the differential diagnosis. While findings of thoracic lymphoma may be evident on chest radiography, computed tomography has traditionally been the imaging modality used to evaluate the disease and effectively demonstrates the extent of intrathoracic involvement and the presence and extent of extrathoracic spread. However, additional modalities such as magnetic resonance imaging of the thorax and (18)F-FDG PET/CT have emerged in recent years and are complementary to CT in the evaluation of patients with lymphoma. Thoracic MRI is useful in assessing vascular, cardiac, and chest wall involvement, and PET/CT is more accurate in the overall staging of lymphoma than CT and can be used to evaluate treatment response.

What a Differential a Virus Makes: A Practical Approach to Thoracic Imaging Findings in the Context of HIV Infection???Part 2, Extrapulmonary Findings, Chronic Lung Disease, and Immune Reconstitution Syndrome

OBJECTIVE The Centers for Disease Control and Prevention reported more than one million people with HIV infection in the United States in 2006, an increase of 11% over 3 years. Worldwide, nearly 34 million people are infected with HIV. Pulmonary disease accounts for 30-40% of acute hospitalizations of HIV-seropositive patients, underscoring the importance of understanding the range of cardiothoracic imaging findings associated with HIV infection. This article will cover extrapulmonary thoracic diseases, chronic lung diseases, and immune reconstitution inflammatory syndrome in HIV-infected patients. Our approach is focused on the radiologists perspective by recognizing and categorizing key imaging findings to generate a differential diagnosis. The differential diagnosis can be further refined by incorporating clinical data, such as patient demographics, CD4 count, and presenting symptoms. In addition, with prolonged survival of HIV-infected patients in the era of highly active antiretroviral therapy, radiologists can also benefit from awareness of imaging features of a myriad of chronic cardiopulmonary diseases in this patient population. Finally, the change of imaging findings and clinical status in response to treatment provides important diagnostic information, such as in immune reconstitution syndrome. CONCLUSION Developing a practical approach to key cardiothoracic imaging findings in HIV-infected patients will aid the radiologist in generating a clinically relevant differential diagnosis and interpretation, thereby improving patient care.

Imaging of Thoracic Neurogenic Tumors

OBJECTIVE Thoracic neurogenic neoplasms may be a diagnostic challenge both clinically and radiologically, ranging from benign, incidentally discovered tumors to aggressive, symptomatic malignancies. These tumors may originate from any nervous structure within the chest and are derived from cells of the nerve sheath, autonomic ganglia, or paraganglia. The nervous anatomy of the thorax is complex, and neurogenic tumors may be found in any mediastinal compartment or in the chest wall. Furthermore, neurogenic tumors may indicate one of many syndromes, particularly when they are multiple. CONCLUSION This article illustrates the complex anatomy of the nervous system within the chest and details important epidemiologic and pathophysiologic features as an approach to neurogenic tumors of the thorax. Key imaging features of neurogenic tumors occurring in the chest are identified, focusing on distinguishing characteristics and the relative advantages of available imaging modalities to further refine a differential diagnosis.

Congenital abnormalities of the pulmonary arteries in adults.

AJR:202, April 2014 (MPR) images that assist in making diagnoses. In this article, we will illustrate key features of congenital pulmonary artery anomalies in adult patients on chest radiography and MDCT. The complementary role of MRI in evaluating specific abnormalities, such as congenital pulmonic stenosis, will also be discussed. The broader topic of pulmonary artery involvement in congenital heart disease is beyond the scope of this article.

Metastasis to the Heart: A Radiologic Approach to Diagnosis With Pathologic Correlation

OBJECTIVE Evaluating metastatic disease to the heart and pericardium, from detection to diagnosis, often requires a multimodality imaging approach. A radiologists ability to evaluate cardiac metastases hinges on an understanding of the epidemiology, anatomy, and imaging features of this disease process. CONCLUSION On surveillance imaging of patients with cancer or when metastatic disease is suspected, detection of metastatic disease may be greatly enhanced by an understanding of which primary tumors metastasize to the heart and the most common routes of spread.

Imaging of pediatric pathology during the Iraq and Afghanistan conflicts

United States Armed Forces radiologists deployed to Afghanistan and Iraq in modern military conflicts may encounter pediatric patients as a casualty of war or when providing humanitarian assistance to the indigenous population. Pediatric patients account for 4–7% of admissions at U.S. military hospitals during the Iraq and Afghanistan conflicts. It is pertinent for radiologists in the humanitarian care team to be familiar with imaging pediatric trauma patients, the pathology endemic to the local population, and delayed presentations of congenital and developmental disorders to adequately care for these patients. The radiological manifestations of various pediatric disorders seen in the setting of the Iraq and Afghanistan conflicts will be explored.