Carlos S. Restrepo

Aortitis: imaging spectrum of the infectious and inflammatory conditions of the aorta.

Aortitis is a general term that refers to a broad category of infectious or noninfectious conditions in which there is abnormal inflammation of the aortic wall. These inflammatory conditions have different clinical and morphologic features and variable prognoses. The clinical manifestations are usually vague and nonspecific and may include pain, fever, vascular insufficiency, and elevated levels of acute phase reactants, as well as other systemic manifestations. As a result, aortitis is often overlooked during the initial work-up of patients with constitutional symptoms and systemic disorders. A multimodality imaging approach is often required for assessment of both the aortic wall and aortic lumen, as well as for surveillance of disease activity and treatment planning. Noninvasive cross-sectional imaging modalities such as magnetic resonance (MR) imaging, MR angiography, and computed tomographic angiography play a critical role in initial evaluation and further assessment of aortitis. Radiologists should be familiar with the clinical features and imaging findings of the different types of aortitis.

Mucoid Impactions: Finger-in-Glove Sign and Other CT and Radiographic Features

Mucoid impaction is a relatively common finding at chest radiography and computed tomography (CT). Both congenital and acquired abnormalities may cause mucoid impaction of the large airways that often manifests as tubular opacities known as the finger-in-glove sign. The congenital conditions in which this sign most often appears are segmental bronchial atresia and cystic fibrosis. The sign also may be observed in many acquired conditions, include inflammatory and infectious diseases (allergic bronchopulmonary aspergillosis, broncholithiasis, and foreign body aspiration), benign neoplastic processes (bronchial hamartoma, lipoma, and papillomatosis), and malignancies (bronchogenic carcinoma, carcinoid tumor, and metastases). To point to the correct diagnosis, the radiologist must be familiar with the key radiographic and CT features that enable differentiation among the various likely causes. CT is more useful than chest radiography for differentiating between mucoid impaction and other disease processes, such as arteriovenous malformation, and for directing further diagnostic evaluation. In addition, knowledge of the patients medical history, clinical symptoms and signs, and predisposing factors is important.

Intramural hematoma of the esophagus: a pictorial essay

Intramural hematoma of the esophagus (IHE) is a rare but well-documented condition that is part of the spectrum of esophageal injuries which includes the more common Mallory–Weiss tear and Boerhaave’s syndrome. Acute retrosternal or epigastric pain is a common clinical feature, which can be accompanied by dysphagia, odynophagia, or hematemesis. An early differentiation from Mallory–Weiss tear, Boerhaave syndrome, ruptured aortic aneurysm, aortic dissection, acute myocardial infarction, or pulmonary pathology can be difficult. Computed tomography (CT) is the imaging modality of choice and characteristically reveals a concentric or eccentric thickening of the esophageal wall with well-defined borders and variable degree of obliteration of the lumen. Measurement of the attenuation values within the lesion will reveal blood density which varies according to the age of the hematoma. CT should be considered the preferred diagnostic technique, thereby facilitating proper clinical management. Early diagnosis is crucial as most patients maybe treated conservatively with good outcome.

KAPOSI SARCOMA OF THE MUSCULOSKELETAL SYSTEM: A REVIEW OF 66 PATIENTS

Kaposi sarcoma (KS) of bone and skeletal muscle is unusual. In this report, the authors review 66 published patients with KS who had involvement of the musculoskeletal system reported from 1925 to 2006. In only 3 patients was acquired immunodeficiency syndrome (AIDS)‐related KS identified within skeletal muscle. Osseous KS lesions were more frequent and occurred with African, classic, and AIDS‐related KS and occurred rarely in transplantation‐associated KS. Patients seldom were asymptomatic. They usually had bone pain with limited mobility or infrequently developed serious sequelae like spinal cord compression. Locally aggressive African and classic KS lesions typically involved the peripheral skeleton; whereas, in patients with AIDS, the axial (vertebrae, ribs, sternum, and pelvis) and/or maxillofacial bones more commonly were involved. Almost all patients had concomitant nonosseous KS lesions. Joint involvement was exceptional, and pathologic fractures were not observed. Computed tomography scans and magnetic resonance images were better at detecting osseous KS lesions, which frequently went undetected on plain x‐ray films or bone scans. Pathologic diagnosis was important to exclude similar lesions like bacillary angiomatosis. Treatment options, including surgery and, in more recent patients, radiation and/or chemotherapy, had limited success. Cancer 2007

The Diaphragmatic Crura and Retrocrural Space: Normal Imaging Appearance, Variants, and Pathologic Conditions

The retrocrural space (RCS) is a small triangular region within the most inferior posterior mediastinum bordered by the two diaphragmatic crura. Multiplanar imaging modalities such as computed tomography and magnetic resonance imaging allow evaluation of the RCS as part of routine examinations of the chest, abdomen, and spine. Normal structures within the retrocrural region include the aorta, nerves, the azygos and hemiazygos veins, the cisterna chyli with the thoracic duct, fat, and lymph nodes. There is a wide range of normal variants of the diaphragmatic crura and of structures within the RCS. Diverse pathologic processes can occur within this region, including benign tumors (lipoma, neurofibroma, lymphangioma), malignant tumors (sarcoma, neuroblastoma, metastases), vascular abnormalities (aortic aneurysm, hematoma, azygos and hemiazygos continuation of the inferior vena cava), and abscesses. An understanding of the anatomy, normal variants, and pathologic conditions of the diaphragmatic crura and retrocrural structures facilitates diagnosis of disease processes within this often overlooked anatomic compartment.

Imaging Patients with Cardiac Trauma

In the United States, trauma is the leading cause of death among those who are 1-44 years old, with cardiovascular injuries representing the second most common cause of traumatic death after central nervous system injuries. Evaluation of trauma patients with suspected cardiac injury may be complex and include electrocardiography, measurement of cardiac biomarkers, and imaging examinations. Contrast material-enhanced computed tomography (CT) has become one of the most valuable imaging tools available for evaluating hemodynamically stable patients with suspected cardiac injury. The presence of hemopericardium, with or without cardiac tamponade, is one of the most significant findings of cardiac injury. Other complications that result from blunt cardiac injury, such as pericardial rupture and cardiac herniation, may be readily depicted at multidetector CT. Assessment of patients with cardiac injuries, particularly those with penetrating injuries, is a challenging and time-critical matter, with clinical and imaging findings having complementary roles in the formation of an accurate diagnosis. Patients who are hemodynamically stable, particularly those with penetrating cardiac injuries, also may benefit from a timely imaging examination. In addition to chest radiography, other available modalities such as transthoracic and transesophageal echocardiography, nuclear medicine, and magnetic resonance imaging may play a role in selected cases.

Silicone pulmonary embolism: Report of 10 cases and review of the literature

Objective: To assess patient outcome and imaging findings of patients with pulmonary embolism of fluid silicone. Methods: Medical records and imaging examinations of 10 patients with respiratory distress after illicit injection of fluid silicone were reviewed. Population consisted of 8 male (6 male-to-female transsexuals) and 2 female subjects. Results: Average age was 29 years. Most common injection sites were gluteal and trochanteric. Respiratory symptoms developed between 15 minutes and 2 days after silicone injection. Five referred fever, 6 developed adult respiratory distress syndrome, and 2 subsequently died. Alveolar hemorrhage was demonstrated on pathological examination in 6, with silicone vacuoles in the lung parenchyma in 3. Computed tomography demonstrated peripheral ground glass opacities with interlobular septal thickening in all and peripheral airspace disease in 7. Conclusions: Illicit injection of large volumes of fluid silicone for cosmetic purposes is associated with pulmonary embolism and acute alveolar hemorrhage and is associated with a significant mortality.

Primary Pericardial Tumors

Primary pericardial tumors are rare and may be classified as benign or malignant. The most common benign lesions are pericardial cysts and lipomas. Mesothelioma is the most common primary malignant pericardial neoplasm. Other malignant tumors include a wide variety of sarcomas, lymphoma, and primitive neuroectodermal tumor. When present, signs and symptoms are generally nonspecific. Patients often present with dyspnea, chest pain, palpitations, fever, or weight loss. Although the imaging approach usually begins with plain radiography of the chest or transthoracic echocardiography, the value of these imaging modalities is limited. Cross-sectional imaging, on the other hand, plays a key role in the evaluation of these lesions. Computed tomography and magnetic resonance imaging allow further characterization and may, in some cases, provide diagnostic findings. Furthermore, the importance of cross-sectional imaging lies in assessing the exact location of the tumor in relation to neighboring structures. Both benign and malignant tumors may result in compression of vital mediastinal structures. Malignant lesions may also directly invade structures, such as the myocardium and great vessels, and result in metastatic disease. Imaging plays an important role in the detection, characterization, and staging of pericardial tumors; in their treatment planning; and in the posttreatment follow-up of affected patients. The prognosis of patients with benign tumors is good, even in the few cases in which surgical intervention is required. On the other hand, the length of survival for patients with malignant pericardial tumors is, in the majority of cases, dismal.

Imaging of nonthrombotic pulmonary embolism: Biological materials, nonbiological materials, and foreign bodies

Nonthrombotic pulmonary embolism is defined as embolization to the pulmonary circulation caused by a wide range of substances of endogenous and exogenous biological and nonbiological origin and foreign bodies. It is an underestimated cause of acute and chronic embolism. Symptoms cover the entire spectrum from asymptomatic patients to sudden death. In addition to obstruction of the pulmonary vasculature there may be an inflammatory cascade that deteriorates vascular, pulmonary and cardiac function. In most cases the patient history and radiological imaging reveals the true nature of the patients condition. The purpose of this article is to give the reader a survey on pathophysiology, typical clinical and radiological findings in different forms of nonthrombotic pulmonary embolism. The spectrum of forms presented here includes pulmonary embolism with biological materials (amniotic fluid, trophoblast material, endogenous tissue like bone and brain, fat, Echinococcus granulosus, septic emboli and tumor cells); nonbiological materials (cement, gas, iodinated oil, glue, metallic mercury, radiotracer, silicone, talc, cotton, and hyaluronic acid); and foreign bodies (lost intravascular objects, bullets, catheter fragments, intraoperative material, radioactive seeds, and ventriculoperitoneal shunts).

Aneurysms and pseudoaneurysms of the pulmonary vasculature.

Aneurysms of the pulmonary vasculature may arise from the pulmonary arteries, bronchial arteries, or pulmonary veins. Their pathophysiology and clinical presentation are variable depending on the underlying condition, some of which have significant morbidity and mortality. Consequently, imaging plays a central role in the diagnosis and treatment planning. This review article presents a classification of the different types of aneurysms that can affect the pulmonary vasculature and reviews the most common conditions associated with them and discusses their imaging presentation.