Diagnostic pitfalls in computed tomography of the chest.

Anatomical variants and imaging artifacts on thoracic computed tomography (CT), when unrecognized as such, can lead to radiological misinterpretation and erroneous diagnosis. This is a concise review of 15 common CT diagnostic pitfalls due to anatomical variants and imaging artifacts which have potential to be misinterpreted as significant pathology, such as neoplasia, infection, traumatic injury, interstitial lung disease, pleural disease, or vascular lesions.

Multiple pulmonary myofibromas mimicking metastatic disease in an adult patient.

We report a case of multiple bilateral pulmonary myofibromas in an asymptomatic 76-year-old man, who was referred to our institution for investiagtion of incidentally discovered pulmonary nodules, orginially suspected to represent pulmonary metastases. Myofibromas are unusual benign neoplasms, infrequent in adults, and rarely affecting the lungs. Pulmonary neurofibromas can mimic lung metastases and their diagnosis requires histopathological assessment.

Pulmonary air embolism associated with proximal bland thrombus.

We report a case of pulmonary air embolism associated with proximal bland thrombus seen on computed tomography pulmonary angiography in a 49-year-old man, who developed acute hypoxia following removal of central venous catheter.

"Distal bright vessel sign" - Novel radiological sign of pulmonary thromboembolism.

We describe a novel radiological sign of pulmonary thromboembolism on computed tomography aortic angiogram. It consists of focal hyperenhancement of pulmonary arteries distal to the pulmonary thrombus, while the thrombus itself remains occult and the rest of pulmonary arteries are hypoattenuating. The sign was observed on computed tomography aortic angiograms in 2 patients assessed for suspected acute aortic syndrome. Pulmonary emboli were subsequently confirmed with computed tomography pulmonary angiography.

Imaging of Thoracic Wall Abnormalities.

Identification of certain abnormalities of the chest wall can be extremely helpful in correctly diagnosing a number of syndromic conditions and systemic diseases. Additionally, chest wall abnormalities may sometimes constitute diagnoses by themselves. In the present pictorial essay, we review a number of such conditions and provide illustrative cases that were retrospectively identified from our clinical imaging database. These include pentalogy of Cantrell, Klippel-Feil syndrome, cleidocranial dysplasia, Poland syndrome, osteopetrosis, neurofibromatosis type 1, Marfan syndrome, Gardner syndrome, systemic sclerosis, relapsing polychondritis, polymyositis/dermatomyositis, ankylosing spondylitis, hyperparathyroidism, rickets, sickle cell anemia, thalassemia, tuberculosis, septic arthritis of the sternoclavicular joint, elastofibroma dorsi, and sternal dehiscence.

Many Faces of Thoracic Histoplasmosis-Pictorial Essay.

Histoplasmosis is primarily a pulmonary fungal infection with a vast array of radiological manifestations, which can mimic a number of thoracic diseases. This article reviews various presentations of histoplasmosis on chest imaging.

Migration of the azygos vein from the azygos fissure to the mediastinum.

We report a case of migration of the azygos vein from an azygos fissure into the mediastinum following a large right pleural effusion.

Interstitial lung disease as a late complication of pulmonary alveolar proteinosis.

Pulmonary alveolar proteinosis is a rare condition characterized by accumulation of intra-alveolar surfactant. Here, we report a case of interstitial lung disease which developed over the years in a patient with pulmonary alveolar proteinosis.

Imaging of Post Transthoracic Needle Biopsy Complications.

When faced with characterization of a suspicious lung lesion, transthoracic needle biopsy (TTNB) is the standard technique used to retrieve a pathological specimen. Usual complications reported for this intervention are pneumothorax, hemorrhage, air embolism, and tumor seeding. This pictorial essay illustrates imaging of these complications.

Giant cell tumor of a rib following denosumab treatment.

Giant cell tumor (GCT) of the bone is an aggressive lytic lesion, commonly treated with surgery. Denosumab is a relatively recently introduced osteoclast activation inhibitor used for neoadjuvant therapy of GCT. Here we report the case of a GCT of a rib undergoing extensive osteosclerosis on computed tomography imaging following treatment with denosumab.

Thoracic Diseases With Musculoskeletal Manifestations and Vice Versa: A Review.

OBJECTIVE: The purpose of this article is to review several thoracic conditions that are associated with certain musculoskeletal radiological abnormalities using imaging of patients with concomitant chest and musculoskeletal manifestations as illustrative examples. CONCLUSION: Radiologic findings of many thoracic diseases are often nonspecific. When standing alone, their interpretation commonly results in long differential diagnosis. However, in certain instances, a reasonably accurate diagnosis can be made based on imaging findings alone.

Melorheostosis of a rib.

Melorheostos is a rare sclerosing bone dysplasia, characterized by cortical and medullary hyperostosis with typical "dripping candle wax" appearance, usually involving the long bones. Here, we present a case of melorheostosis of a rib, incidentally discovered in an asymptomatic adult patient.

Incidental retroaortic left innominate vein in adult patient.

Retro-aortic left innominate vein is a rare vascular abnormality, usually associated with congenital heart disease. Here we report a case of isolated retro-aortic left innominate vein in an adult female.

Ortner syndrome secondary to aortic aneurysm.

Ortner syndrome refers to vocal cord paralysis resulting from compression of the left recurrent laryngeal nerve by abnormal mediastinal vascular structures. We report a case of Ortner syndrome in a 75-year-old male secondary to aortic arch aneurysm.

Hemiazygous-accessory hemiazygous continuation of double inferior vena cava.

We report a case of hemiazygous-accessory hemiazygous continuation of a double IVC with absent azygous vein, incidentally discovered in an adult patient.

Detection of central pulmonary embolism on non-contrast computed tomography: a case control study.

The purpose of our study was to evaluate detection of central pulmonary embolism (PE) on non-contrast CT. The unenhanced series (PA localizer, 5 mm slice thickness) of 180 CT pulmonary angiograms (CTPA) [90 consecutive CTPA positive for central and proximal interlobar PE taken from 3,161 consecutive CTPA (2.85 % prevalence) mixed with 90 randomly selected negative controls] were independently reviewed by two radiologists (R1 and R2). This was subsequently followed by concluding validation from a third radiologist with access to contrast-enhanced CTPA images and official reports. Six suboptimal studies were excluded. Patient age, gender, hemoglobin value and clot location were recorded. Interobserver agreement, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were determined. Sensitivity, specificity, PPV and NPV were 65 % [95 % confidence interval (CI) 54-75 %, 57/88], 49 % (95 % CI 38-60 %, 42/86), 3.6 % (95 % CI 2.8-4.6 %),97.9 % (95 % CI 97.1-98.6 %) for R1, and 55 % (95 % CI 44-65 %, 48/88), 76 % (95 % CI 65-84 %, 65/86), 6.2 % (95 % CI 4.3-9.3 %), 98.3 % (95 % CI 97.8-98.7 %) for R2. Patient age, sex and hemoglobin value were found to have no impact on PE detection. For strictly central PE, sensitivity was 80 % (45/56) (R1) and 70 % (39/56) (R2), while for bilateral PE, sensitivity was 74 % (48/65) (R1) and 66 % (43/65) (R2). For truly positive PE, interobserver agreement was 67 % (59/88) with a moderate Cohen's kappa of 0.41 (95 % CI 0.24-0.57). In conclusion, non-contrast CT shows high NPV for central PE identification, however it is neither sensitive nor specific enough to accurately detect it.

Nonthrombotic pulmonary embolism.

OBJECTIVE: The purpose of this essay is to highlight the clinical features and imaging findings associated with different types of nonthrombotic pulmonary embolism. CONCLUSION: Nonthrombotic pulmonary embolism is an infrequent condition with various causes that can be life-threatening pathologic conditions. The entity presents a diagnostic challenge because of the low specificity of clinical symptoms and imaging signs. Awareness of the imaging features of nonthrombotic pulmonary embolism facilitates correct diagnosis and leads to appropriate patient care.

"V V O I": a swift hand motion in detecting atelectasis on frontal chest radiographs.

This article introduces an easy and practical way to help detect lobar atelectasis on frontal chest radiographs. A proposed "V V O I" hand motions method is detailed in his article. This method depends on 4 simple hand motions, which could help detect 4 important direct and indirect corresponding signs of atelectasis. Our aim is to introduce the "V V O I" trick as a memory aid to facilitate detecting difficult cases of lung collapse, particular for nonradiologists and radiologists in training. The importance of using this method in conjunction with the lateral chest radiograph is emphasized. I addition, several pitfalls in using this method are also explained.