I saw the sign: He felt a pang and we saw the Yin-Yang (sign).

The yin-yang sign, also known as the Pepsi sign, is used to describe the classic appearance of bidirectional blood flow within an aneurysm or pseudoaneurysm sac on color Doppler ultrasound. The corresponding spectral Doppler finding is a "to-and-fro" waveform, caused by inflow to the aneurysm/pseudoaneurysm sac during systole and outflow during diastole. It is important to recognize this sign in order to quickly identify the presence of an aneurysm or pseudoaneurysm and prevent complications such as expansion and rupture.

Lung Imaging in COPD Part 1: Clinical Usefulness.

COPD is a condition characterized by chronic airflow obstruction resulting from chronic bronchitis, emphysema, or both. The clinical picture is usually progressive with respiratory symptoms such as exertional dyspnea and chronic cough. For many years, spirometry was used to establish a diagnosis of COPD. Recent advancements in imaging techniques allow quantitative and qualitative analysis of the lung parenchyma as well as related airways and vascular and extrapulmonary manifestations of COPD. These imaging methods may allow prognostication of disease and shed light on the efficacy of pharmacologic and nonpharmacologic interventions. This is the first of a two-part series of articles on the usefulness of imaging methods in COPD, and it highlights useful information that clinicians can obtain from these imaging studies to make more accurate diagnosis and therapeutic decisions.

Lung Imaging in COPD Part 2: Emerging Concepts.

The diagnosis, prognostication, and differentiation of phenotypes of COPD can be facilitated by CT scan imaging of the chest. CT scan imaging of the chest is a prerequisite for lung volume reduction surgery and lung transplantation. Quantitative analysis can be used to evaluate extent of disease progression. Evolving imaging techniques include micro-CT scan, ultra-high-resolution and photon-counting CT scan imaging, and MRI. Potential advantages of these newer techniques include improved resolution, prediction of reversibility, and obviation of radiation exposure. This article discusses important emerging techniques in imaging patients with COPD. The clinical usefulness of these emerging techniques as they stand today are tabulated for the benefit of the practicing pulmonologist.

Mature Type T-Lymphoblastic Leukemia/Lymphoma Presenting With Isolated Central Nervous System Symptomatology in a Patient With Giant Cell Arteritis on Long-Term Steroid Treatment.

T-lymphoblastic leukemia/lymphoma (T-ALL/T-LBL) is a malignancy comprised of T-lymphoblasts that can present as one of four clinical subtypes (pro-T, pre-T, cortical T, and mature T). Clinical presentation is typically characterized by leukocytosis with diffuse lymphadenopathy and/or hepatosplenomegaly. Beyond clinical presentation, specific immunophenotypic and cytogenetic classifications are utilized to diagnose mature T-ALL. In later disease stages it can spread to the central nervous system (CNS); however, presentation of mature T-ALL by way of CNS pathology and clinical symptomatology alone is rare. Even more rare is the presence of poor prognostic factors without correlating significant clinical presentation. We present a case of mature T-ALL in an elderly female with isolated CNS symptoms in combination with poor prognostic factors including terminal deoxynucleotidyl transferase (TdT) negativity and a complex karyotype. Our patient lacked the classical symptomatology and laboratory findings of mature T-ALL but deteriorated quickly upon diagnosis due to the aggressive genetic profile of her cancer.

A 53-Year-Old With Progressive Dyspnea.

CASE PRESENTATION: A 53-year-old woman with a history of pulmonary embolism treated with rivaroxaban came to the ED after 4 days of acutely worsening dyspnea and chest pressure. On arrival, her temperature was 36.7 °C; heart rate, 71 beats/min; BP, 98/59 mm Hg; respiratory rate, 22 breaths/min; and Spo2 95% on room air. Her WBC count was elevated at 15,770/µL; hemoglobin, 13.3 g/dL; platelets, 280,000/µL; INR (international normalized ratio), elevated at 1.66; and partial thromboplastin time, elevated at 18.8 s. Serum chemistry results were unremarkable, and pro-brain natriuretic peptide was slightly elevated at 530 pg/mL (normal, < 300 pg/mL).

Cough and Progressive Pleuritic Chest Pain With an Enlarging Cavity on Imaging.

CASE PRESENTATION: A 49-year-old woman sought treatment at the hospital for evaluation of an enlarging cavitary mass of the right lung associated with worsening ipsilateral pleuritic chest pain and cough. She had recent hospitalizations for complications relating to recurrent lung abscesses, including one in which she underwent wedge resection of the right lung. She had been treated with several courses of antibiotics, which only temporarily relieved her symptoms. She did not report any fevers, chills, skin changes, diarrhea, or changes to her bowel habits. Her long-term medications included albuterol, dapsone, and prednisone 15 mg or 20 mg doses alternating daily. Her only past medical history was asthma and primary cutaneous pyoderma gangrenosum. The patient never smoked and did not report any recent sick contacts.

A 33-Year-Old Man With Chest Pain.

CASE PRESENTATION: A 33-year-old man was admitted with a 4-week history of intermittent, right-sided chest pain. Two weeks before the incident, he had completed a 10-day course of levofloxacin for a presumed right-sided pneumonia without much improvement. He denied any dyspnea, cough, sputum production, hemoptysis, night sweats, or weight loss. He was an active smoker with a 20-pack-year smoking history and 1-year history of vaping nicotine.

Algorithmic Approach to the Diagnosis of Organizing Pneumonia: A Correlation of Clinical, Radiologic, and Pathologic Features.

Organizing pneumonia (OP), characterized histopathologically by patchy filling of alveoli and bronchioles by loose plugs of connective tissue, may be seen in a variety of conditions. These include but are not limited to after an infection, drug reactions, radiation therapy, and collagen vascular diseases. When a specific cause is responsible for this entity, it is referred to as "secondary OP." When an extensive search fails to reveal a cause, it is referred to as "cryptogenic OP" (previously called "bronchiolitis obliterans with OP"), which is a clinical, radiologic, and pathologic entity classified as an interstitial lung disease. The clinical presentation of OP often mimics that of other disorders, such as infection and cancer, which can result in a delay in diagnosis and inappropriate management of the underlying disease. The radiographic presentation of OP is polymorphous but often has subpleural consolidations with air bronchograms or solitary or multiple nodules, which can wax and wane. Diagnosis of OP sometimes requires histopathologic confirmation and exclusion of other possible causes. Treatment usually requires a prolonged steroid course, and disease relapse is common. The aim of this article is to summarize the clinical, radiographic, and histologic presentations of this disease and to provide a practical diagnostic algorithmic approach incorporating clinical history and characteristic imaging patterns.

Intermittent Cough and Hemoptysis With Tree-in-Bud Opacities on Imaging.

CASE PRESENTATION: A 44-year-old man with hyperthyroidism and no smoking history presented to his internist with 5 months of intermittent cough and hemoptysis. The patient's family history was remarkable only for non-Hodgkin's lymphoma in his father. He had a history of a 25-day exposure to a home renovation at work 2 years prior to presentation. He was treated with oral clarithromycin with no improvement in his symptoms. A chest radiograph showed bilateral nodular opacities with a left lower lobar consolidative opacity (Fig 1A, 1B); the patient underwent CT scanning of the chest, which showed areas of nodular infiltration in the lower lobes with tree-in-bud-like opacities. He was referred to a pulmonologist.

Incidence, Impact, and Management of Incidentalomas on Preoperative Computed Tomographic Angiograms for Breast Cancer Patients with and without Genetic Mutations.

BACKGROUND: Preoperative abdominal computed tomographic angiograms for free flap breast reconstruction improve operative safety and efficiency, but incidental findings are common and potentially affect management. In addition, the authors hypothesized that patients with genetic mutations might have a higher rate of significant findings. The authors present the largest series of computed tomographic angiogram "incidentalomas" in these two populations and an evidence-based algorithm for managing common findings. METHODS: All patients undergoing free flap breast reconstruction at Northwell Health between 2009 and 2017 were eligible. Medical history, perioperative details, and radiology reports were examined with abnormal findings recorded. Published literature was reviewed with radiologists to develop standardized guidelines for incidentaloma management. RESULTS: Of 805 patients included, 733 patients had abdominal imaging. One hundred ninety-five (27 percent) had a completely negative examination. In the remaining 538 patients, benign hepatic (22 percent) and renal (17 percent) findings were most common. Sixteen patients (2.2 percent) required additional imaging (n = 15) or procedures (n = 5). One finding was concerning for malignancy-renal cell carcinoma-which interventional radiology ablated postoperatively. Seventy-nine patients (10.8 percent) had a genetic mutation but were not found to have a statistically significant higher rate of incidentalomas. CONCLUSIONS: The authors' rate of computed tomographic angiography incidental findings (73 percent) is consistent with previous studies, but the rate requiring further intervention (2.2 percent) is lower. Incidental findings were no more common or pathologic among genetic mutation carriers. The authors also introduce an evidence-based algorithm for the management of common incidentalomas. Using these guidelines, plastic surgeons can reassure patients, regardless of mutation status, that incidentalomas are most commonly benign and have minimal impact on their surgical plan.

The Usefulness of Chest CT Imaging in Patients With Suspected or Diagnosed COVID-19: A Review of Literature.

The COVID-19 pandemic has had devastating medical and economic consequences globally. The severity of COVID-19 is related, in a large measure, to the extent of pulmonary involvement. The role of chest CT imaging in the management of patients with COVID-19 has evolved since the onset of the pandemic. Specifically, the description of CT scan findings, use of chest CT imaging in various acute and subacute settings, and its usefulness in predicting chronic disease have been defined better. We performed a review of published data on CT scans in patients with COVID-19. A summary of the range of imaging findings, from typical to less common abnormalities, is provided. Familiarity with these findings may facilitate the diagnosis and management of this disease. A comparison of sensitivity and specificity of chest CT imaging with reverse-transcriptase polymerase chain reaction testing highlights the potential role of CT imaging in difficult-to-diagnose cases of COVID-19. The usefulness of CT imaging to assess prognosis, to guide management, and to identify acute pulmonary complications associated with SARS-CoV-2 infection is highlighted. Beyond the acute stage, it is important for clinicians to recognize pulmonary parenchymal abnormalities, progressive fibrotic lung disease, and vascular changes that may be responsible for persistent respiratory symptoms. A large collection of multi-institutional images were included to elucidate the CT scan findings described.

Congenital Descending Aorta to Pulmonary Vein Fistula: Imaging Findings and Differential Diagnosis.

Congenital descending aorta to pulmonary vein fistula (cDAPVF) is an extremely rare vascular abnormality that is usually diagnosed in infancy. Patients can become symptomatic, presenting with heart failure and hemoptysis. It is important to differentiate cDAPVF from its potential mimickers due to differences in treatment implications. In this pictorial essay, we will highlight the pathophysiology and key imaging findings of cDAPVF and how to separate it from its more common mimickers using cases that presented at our institution.

Lung Hyperlucency: A Clinical-Radiologic Algorithmic Approach to Diagnosis.

Areas of diminished lung density are frequently identified both on routine chest radiographs and chest CT examinations. Colloquially referred to as hyperlucent foci of lung, a broad range of underlying pathophysiologic mechanisms and differential diagnoses account for these changes. Despite this, the spectrum of etiologies can be categorized into underlying parenchymal, airway, and vascular-related entities. The purpose of this review is to provide a practical diagnostic algorithmic approach to pulmonary hyperlucencies incorporating clinical history and characteristic imaging patterns to narrow the differential.

An Algorithmic Approach to the Interpretation of Diffuse Lung Disease on Chest CT Imaging: A Theory of Almost Everything.

We propose an algorithmic approach to the interpretation of diffuse lung disease on high-resolution CT. Following an initial review of pertinent lung anatomy, the following steps are included. Step 1: a preliminary review of available chest radiographs, including the "scanogram" obtained at the time of the CT examination. Step 2: a review of optimal methods of data acquisition and reconstruction, emphasizing the need for contiguous high-resolution images throughout the entire thorax. Step 3: initial uninterrupted scrolling of contiguous high-resolution images throughout the chest to establish the quality of examination as well as an overview of the presence and extent of disease. Step 4: determination of one of three predominant categories - primarily reticular disease, nodular disease, or diseases associated with diffuse alteration in lung density. Based on this determination, one of the three following Steps are followed: Step 5: evaluation of cases primarily involving diffuse lung reticulation; Step 6: evaluation of cases primarily resulting in diffuse lung nodules; and Step 7: evaluation of cases with diffuse alterations in lung density including those with diffusely diminished lung density vs those with heterogenous or diffusely increased lung density, respectively. It is anticipated that this algorithmic approach will substantially enhance initial interpretations of a wide range of pulmonary disease.

Imaging of Pulmonary Hypertension: Pictorial Essay.

Pulmonary hypertension (PH) is an end result of a diverse array of complex clinical conditions that invoke hemodynamic and pathophysiological changes in the pulmonary vasculature. Many patients' symptoms begin with dyspnea on exertion for which screening tests such as chest roentgenograms and more definitive noninvasive tests such as CT scans are ordered initially. It is imperative that clinicians are cognizant of subtle clues on these imaging modalities that alert them to the possibility of PH. These clues may serve as a stepping stone towards more advanced noninvasive (echocardiogram) and invasive (right heart catheterization) testing. On the CT scan, the signs are classified into mediastinal and lung parenchymal abnormalities. In addition to suspecting the diagnosis of PH, this paper provides a pictorial essay to guide health care professionals in identifying the etiology of PH. This paper also provides concrete definitions, wherever possible, of what constitutes abnormalities in PH, such as dilated pulmonary arteries, pruning of vessels, and increased thickness of free wall of the right ventricle. The sensitivities and specificities of each sign are enumerated. The common radiographic and clinical features of many different etiologies of PH are tabulated for the convenience of the readers. Some newer imaging modalities such as dual-energy CT of the chest that hold promise for the future are also described.

A 58-Year-Old Woman With Back Pain and an Unusual Diagnosis.

CASE PRESENTATION: A 58-year-old postmenopausal woman presented to her primary care physician with lower back pain. She denied respiratory symptoms. Her medical history is significant for hypertension, hyperlipidemia, and prediabetes. Her surgical history consists of a tonsillectomy and a remote dilatation and curettage procedure. She denied a history of smoking, alcohol use, or recreational drug use. A review of systems was otherwise negative.

Cavitary Lung Diseases: A Clinical-Radiologic Algorithmic Approach.

Cavities occasionally are encountered on thoracic images. Their differential diagnosis is large and includes, among others, various infections, autoimmune conditions, and primary and metastatic malignancies. We offer an algorithmic approach to their evaluation by initially excluding mimics of cavities and then broadly classifying them according to the duration of clinical symptoms and radiographic abnormalities. An acute or subacute process (< 12 weeks) suggests common bacterial and uncommon nocardial and fungal causes of pulmonary abscesses, necrotizing pneumonias, and septic emboli. A chronic process (≥ 12 weeks) suggests mycobacterial, fungal, viral, or parasitic infections; malignancy (primary lung cancer or metastases); or autoimmune disorders (rheumatoid arthritis and granulomatosis with polyangiitis). Although a number of radiographic features can suggest a diagnosis, their lack of specificity requires that imaging findings be combined with the clinical context to make a confident diagnosis.