Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

1,922 results found
Article

Absent azygos vein

An absent azygos vein is a very uncommon variant in which the azygos vein fails to develop. In cases of agenesis of the azygos vein, the hemiazygos and accessory hemiazygos veins play an important role in venous drainage, accounting for drainage of both the right and left intercostal veins 1-3. ...
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Gastropericardial fistula

Gastropericardial fistulas are rare abnormal communications between the stomach and the pericardial sac. This is a life-threatening condition that can lead to impaired cardiac function, sepsis and eventually death. Clinical presentation Patients with gastropericardial fistula may present with ...
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Mediastinal lipoma

A mediastinal lipoma is a benign fat-containing mediastinal lesion. Pathology Similar to lipomas elsewhere and except in rare situations comprise of mature adipocytes. They can be variable in size. They are usually seen as an encapsulated mass with homogeneous fat attenuation. These lesions oc...
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Bronchomediastinal trunk

The bronchomediastinal trunks (a.k.a. bronchomediastinal lymphatic trunks) are lymphatic trunks, one on each side of the body. On the left, the bronchomediastinal trunk is a tributary of the thoracic duct, and on the right, it is a tributary of the right lymphatic duct. Although, in some individ...
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Blunting of the costophrenic angle

Blunting of the costophrenic angle (also known as blunting of the costophrenic sulcus) is a chest radiograph sign usually indicative of a small pleural effusion. It may be seen on either frontal or lateral erect projections. It has been found that approximately 200 mL pleural fluid needs to be p...
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CT chest abdomen-pelvis (protocol)

The CT chest-abdomen-pelvis protocol serves as an outline for an examination of the trunk covering the chest,  abdomen and pelvis. It is one of the most common CT examinations conducted in routine and emergencies. It can be combined with a CT angiogram. Note: This article aims to frame a genera...
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Bird’s nest sign (lungs)

The bird’s nest sign refers to the appearance created by a reverse halo sign with associated irregular and intersecting areas of stranding or irregular lines within the area of ground-glass opacity 1. Both bird's nest sign and reverse halo signs are suggestive of invasive pulmonary fungal infec...
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Cartilage

Cartilage or cartilaginous tissue is a resilient and type of connective tissue of mesodermal origin that forms an integral part within the musculoskeletal system and as a structural component in other organs.   Cartilage can be generally classified into the following main types: hyaline cartil...
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Diaphragmatic lung hernia

A diaphragmatic lung hernia (plural: hernias or herniae) is extremely rare, characterized by a lung herniation through the diaphragm into the abdominal cavity. There has been a single case report 2. It is questionable whether this entity truly exists at all 3. This is not to be confused with th...
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Cervical lung hernia

Cervical lung hernias (alternative plural: herniae), also known as apical lung hernias, are a subtype of lung hernias in which lung protrudes through the apex of the thoracic cavity. Epidemiology Lung herniation of any form is rare. Cervical lung hernia is thought to represent only ~20% lung h...
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Compensatory lung hyperinflation

Compensatory lung hyperinflation (a.k.a. compensatory lung overinflation) is a situation in which due to loss of volume of a lung, unaffected parts of the same lung overinflate as compensation. In more severe cases, the contralateral lung may also overinflate with possible mediastinal shift towa...
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Adalimumab induced interstitial lung disease

Adalimumab induced interstitial lung disease is a form of anti-TNF-induced diffuse interstitial lung disease from the broader category of drug induced lung disease. The disease occurs as a response to the disease modifying anti-rheumatic drug adalimumab or HumiraTM. Pathology Exact mechanism o...
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CT transcatheter aortic valve implantation planning (protocol)

The transcatheter aortic valve implantation or TAVI planning CT protocol is used to plan for transcatheter aortic valve implantation. CT allows for the assessment of the aortic root and valve annulus in order to select an appropriate valve size and location-specific to the patient. An aortic ang...
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Lung bases

Anatomically, the lung bases refer literally to the inferior concave surfaces of the lungs which directly contact the hemidiaphragms. However many radiologists, and other clinicians, use the term more generally to refer to the basal region of the lung, which like the lower zones, has no formal ...
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Endobronchial tuberculosis

Endobronchial tuberculosis is an infection along the bronchial walls +/- involvement of the lumen by tuberculosis. It may affect any part of the bronchial tree. It can occur with other forms of pulmonary tuberculosis and occurrence on its own is considered rare 1. Pathology It may affect any l...
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En face

En face (pronounced /ɒ̃ ˈfas/) is a term used in radiology, mainly in plain radiography, to refer to structures or pathology that are seen front on.
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Pleurodesis

Pleurodesis is a procedure that involves the administration of an agent into the pleural space to cause adhesion to the chest wall (usually from adhesion between the parietal and the visceral layers of the pleura). Usually an irritative chemical agent (chemical pleurodesis) and rarely microbiolo...
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Honeycomb sterna

Honeycomb sterna are considered as a rare developmental variant of the sternum, resulting from unfused lateral ossification centers of the sternebrae, which gives a honeycomb configuration of the mesosternum. Usually asymptomatic and discovered incidentally during a routine exam of the chest.
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Viscera

The viscera (singular: viscus) refers to all the internal organs within the major cavities of the thorax, abdomen and pelvis. Therefore it does not include organs of the CNS, head and neck or musculoskeletal compartments nor does it encompass non-internal organs (e.g. the skin) 1. Splanchnology...
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Pulmonary trunk dilatation

Dilatation of the pulmonary trunk or dilatation of the main pulmonary artery (mPA) has a range of causes, and is often (though not always) associated with pulmonary hypertension. Most publications suggest an upper limit of normal in the region of 29-33 mm 1, which can be higher in males 7. Othe...
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Stenotrophomonas maltophilia pneumonia

Stenotrophomonas maltophilia pneumonia refers to a pneumonia resulting from the organism Stenotrophomonas maltophilia, which is a common colonizer of the respiratory tract of patients with chronic lung disease. The organism is considered highly resistant to antibiotics. Radiographic features C...
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Mitral valve replacement

Mitral valve replacement refers to the substitution of the mitral valve either by a mechanical valve or bioprosthesis. Indications Mitral valve replacement has been superseded by mitral valve repair in most situations of mitral valve dysfunction 1-3. Further existing indications of operative m...
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Years criteria for pulmonary embolism

The YEARS criteria is a diagnostic algorithm that determines the risk of pulmonary embolism (PE) derived from three items in the Wells score that are most predictive of PE1. Unlike the Wells score, it uses a variable D-dimer threshold based off clinical pre-test probability. The YEARS criteria i...
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Centrilobular (disambiguation)

The term centrilobular in imaging may refer to: centrilobular (lungs) centrilobular pattern (ultrasound liver)
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D sign (right ventricle)

A D-shaped left ventricle or flattening of the interventricular septum with a D-shaped configuration is a feature described with significant right ventricular (RV) overload / right heart strain such as that occurring with complications of a sizable pulmonary embolic event. It was initially descr...
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Polymer fume fever

Polymer fume fever is a rare condition secondary to the breathing in of fumes from PTFE, a common household plastic. It is often misdiagnosed as a viral flu-like illness. Most people make a rapid recovery, although severe morbidity may be seen. Epidemiology A Japanese group found 18 cases of p...
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Roesler sign

Roesler sign is the name given to the inferior rib notching seen in coarctation of the aorta. Although by no means pathognomonic, the sign is fairly specific. Although many other causes of inferior rib notching have been recorded most of them are very rare 1. Strictly-speaking it is only called...
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CT esophagography

CT esophagography is a CT study designed to primarily evaluate the esophagus, particularly in the situation of esophageal trauma and potential perforation. It has been developed partly as an alternative to fluoroscopic barium swallow evaluation in this situation. Indications potential esophage...
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Aortic arch aneurysm

An aortic arch aneurysm is a less common form of thoracic aortic aneurysm and may account for around 10% of such aneurysms. Epidemiology There is a recognized male predilection with most patient's presenting around to 6th to 7th decades of life. Clinical presentation It can be clinically sil...
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Doughnut sign (chest)

The doughnut sign can be appreciated on the lateral chest radiograph of patients with mediastinal adenopathy, most commonly seen in pediatric patients with pulmonary tuberculosis infection1. The sign is made up of precarinal, subcarinal and retrocarinal lymph nodes which surround the radiolucen...
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Thin walled cystic lung cancer

Thin walled cystic lung cancers are a rare morphological form of lung cancers which on imaging appears as a thin walled (usually 1-4 mm wall thickness) cystic space. There is some overlap with the term lung cancer associated with cystic airspaces. They may develop suspicious features on serial i...
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Main bronchi

The main bronchi is the collective term given to the left and right main bronchi which are formed by the bifurcation of the trachea at the carina, supplying air to the right and left lungs respectively.  The main bronchi form part of the lower respiratory tract and are conducting airways, i.e. ...
Article

Respiratory tract

The respiratory tract refers to the portion of the respiratory system that conducts air into and out of the body. It is conventionally divided into upper and lower tracts. The upper respiratory tract (URT), also known as the upper airways, is the collective term for the components of the respir...
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Particulate material pulmonary embolism

Particulate material pulmonary embolism (PE) is a type of non-thrombotic pulmonary embolism caused by a variety of non-organic particulate materials. These can include  talc embolism cement embolism: comprised of polymethyl methacrylate (PMMA) iodinated oil embolism metallic pulmonary embol...
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Subendocardial fat infiltration

Subendocardial fat infiltration is a finding that can be seen with thoracic and cardiac imaging. It forms a part of myocardial fat infiltration and can sometimes be seen in the setting of a long-gone myocardial infarction 1 especially if seen in the distribution territory of a coronary artery an...
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Pleural pointillism

Pleural pointillism is multiple high signal regions on b=1000 diffusion-weighted imaging but not at lower b-values. It can be a reliable tool allowing differentiation of malignant from benign pleural lesions and can help guide biopsy 1-3.  Its sensitivity is reported to be 93-100% and specificit...
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Bilateral pleural effusion

Bilateral pleural effusions can be common in general radiology practice. They may be symmetrical or asymmetrical. They can occur from several varied etiologies although congestive heart failure (CHF), renal or liver failure are generally considered common 1.   Recognized list of causes are many...
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Bronchial hyperresponsiveness

Bronchial hyperresponsiveness or airway hyperresponsiveness consists of an increased sensitivity of the airways to an inhaled constrictor agonist. It has been described as a characteristic feature of asthma and has also been known to occur in association with other factors such as indexed body m...
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Absent pulmonary valve syndrome

Absent pulmonary valve syndrome (APVS) also known as congenital absence of pulmonary valve or pulmonary valve agenesis is a rare cardiac outflow tract anomaly.  Pathology It is characterized by a completely absent or rudimentary pulmonary valve. It can be associated with aneurysmal dilatation ...
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Pulmonary target sign

The pulmonary target sign has been described in the lung parenchyma as a central high attenuation focus surrounded by one or more dense complete or incomplete ring-like consolidation, forming one or more circles. This sign has been predominantly reported on non-contrast chest CT in patients with...
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Bronchial dehiscence

Bronchial dehiscence refers to loss of integrity of a bronchus which is most commonly encountered as an anastomotic (airway) dehiscence following lung transplantation (as a lung transplant complication). It can also refer to a bronchial stump dehiscence following a lobectomy.
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Mercury embolism

Mercury embolism ​is a rare condition caused by the embolism of elemental mercury secondary to suicidal or accidental intravenous injection 1,4. Pathology Etiology Mercury embolism is primarily from intravenous injection of elemental mercury although it has rarely been seen secondary to inges...
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Paclitaxel lung toxicity

Paclitaxel lung toxicity is a form of drug induced lung disease that can precipitate following the use of paclitaxel which is a chemotherapeutic agent commonly used in the treatment of breast, ovarian, and non-small cell lung cancers. Two forms have been described: hypersensitivity reactions 1...
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Contrast-enhanced CT during extracorporeal membrane oxygenation

Contrast-enhanced CT of patients undergoing extracorporeal membrane oxygenation (ECMO) presents unique technical and diagnostic challenges. Technical considerations  There are a number of factors that need to be considered to ensure contrast-enhanced CT studies of ECMO patients are both succes...
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Horseshoe-shaped (disambiguation)

Several normal anatomical structures and rare organ variants have been described as being horseshoe-shaped. Organ anomalies horseshoe kidney horseshoe lung horseshoe adrenal horseshoe appendix horseshoe pancreas 1 Horseshoe-shaped organs hyoid bone limbic lobe supramarginal gyrus tymp...
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Neuron specific enolase

Neuron specific enolase (NSE) is a cell specific isoenzyme of the glycolytic enzyme enolase. It is sometimes considered as a tumor marker.  Elevated neuron specific enolase levels have shown to occur in association with:  tumors small cell lung cancer: up to 70% of patients with small cell lu...
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Trichoptysis

Trichoptysis (rare plural: trichoptyses) is an extremely rare symptom, whereby patients cough up hair. It is highly specific for rupture of a mediastinal teratoma into the tracheobronchial tree, however it is not pathognomonic as several articles claim (see below) 1,2. Nevertheless it remains a ...
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Paradoxical reaction in tuberculosis

A paradoxical reaction in tuberculosis refers to a clinical or radiological worsening of pre-existing tuberculous lesions or the development of new lesions, in patients receiving anti-tuberculous medication who may have initially improved on treatment. Pathology The exact mechanism is not well...
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Bunch of grapes sign (bronchiectasis)

The bunch of grapes sign, a.k.a. cluster of grapes sign, is a characteristic imaging finding on CT seen in bronchiectasis. Closely apposed dilated bronchi may look like multiple adjacent thin walled cysts which mimic the appearance of a bunch of grapes.
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Subpleural pulmonary nodules

Subpleural pulmonary nodules are a location-based category of pulmonary nodules and are also often considered a type of perilymphatic nodule. Pathology Location In most cases, they abut the costal pleural surfaces directly, and to a lesser degree the diaphragmatic and mediastinal pleural surf...
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Keutel syndrome

Keutel syndrome is an extremely rare inherited condition. Clinical presentation It is characterized by: cartilage calcification of: ears nose larynx trachea - with resultant tracheobronchial stenosis ribs pulmonary arterial stenoses brachytelephalangism (short fingers and nails that re...
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Tracheobronchial stenosis

Tracheobronchial stenosis is a descriptive term given to a spectrum of disorders that can result in focal or diffuse narrowings of the trachea and bronchi. The term encompasses: tracheal stenosis bronchial stenosis Radiographic assessment CT MinIP images are often helpful for better appreci...
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Venous thoracic outlet syndrome

The venous thoracic outlet syndrome is the second commonest form of thoracic outlet syndrome (with neurogenic thoracic outlet syndrome being the commonest and the arterial thoracic outlet syndrome being the least common). Clinical presentation It may develop suddenly, often after unusual and t...
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Pulmonary arterial ectasia

Pulmonary arterial ectasia refers to more diffuse dilatation of the pulmonary arteries without a focal pulmonary arterial aneurysm. At the time of writing, the upper limit of normal (90th percentile) for the main pulmonary arteries is taken at just under 29 mm for males and just under 27 mm for ...
Article

True thymic hyperplasia

True thymic hyperplasia is a form of thymic hyperplasia where there is enlargement of the thymus but with its normal structure being retained.  Pathology The underlying pathogenesis of true thymic hyperplasia is largely unknown.  There is an increase of both size and weight of the gland but w...
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Sarcoidosis (cutaneous manifestations)

The cutaneous manifestations of sarcoidosis occur in ~30%1 (range 9-37%) 3 of patients with sarcoidosis. A skin lesion may be the initial presentation of sarcoidosis and the majority of patients with cutaneous manifestations will have pulmonary disease. Pathology Common lesions maculopapular ...
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Centrilobular micronodules

Centrilobular micronodules are an image descriptor that refers to centrilobular nodules when the nodules are very small and present in a centrilobular distribution in the lungs. They are usually seen with bronchiolitis and can blend into tree-in-bud opacities.  Radiographic features CT Postpr...
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Hemithoracic volume loss (differential)

Hemithoracic volume loss can occur from a number of situations. These include: Congenital  pulmonary hypoplasia (unilateral) isolated unilateral pulmonary artery agenesis skeletal deformities - e.g. kyphosis,  Acquired Infection in childhood  Swyer-James syndrome Other infective/inflamma...
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Interstitial lung disease associated with systemic sclerosis

Interstitial lung disease associated with systemic sclerosis (SSc-ILD) is one of the important pulmonary manifestations of systemic sclerosis. It usually gives a NSIP type pattern with an UIP pattern occurring less commonly 7. It can sometimes produce a rapidly progressive interstitial lung dise...
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Railway track sign

The railway track sign may be used in chest radiography or CT to refer to the appearance of contrast in the pulmonary artery surrounding a partial filling defect in the setting of acute pulmonary embolism. Acute embolus sits centrally and is surrounded by contrast media on CTPA. When such vesse...
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High attenuation mucus

High-attenuation mucus (HAM) is a form of mucoid impaction which is often considered a characteristic and an "almost pathognomonic" feature of allergic bronchopulmonary aspergillosis (ABPA) (close to 100% specificity) 1. Epidemiology It may be present in up to 28% of patients with allergic bro...
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Emphysema (disambiguation)

Emphysema refers to any disease process involving an abnormal accumulation of air/gas in the tissues. When used alone, it is usually taken to mean the lung disease, pulmonary emphysema, which forms part of the spectrum of chronic obstructive pulmonary disease (COPD).  gastric emphysema: include...
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Pleural silicone granuloma

Pleural silicone granulomas result from an extremely rare situation where there is leakage of silicone from an implant rupture into the thorax.  Pathology It is thought that scars from remote thoracotomy may provide a potential pathway for ruptured silicone to fistulise into the pleural space....
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Carbon monoxide transfer coefficient

Carbon monoxide transfer coefficient (often abbreviated as KCO) is a parameter often performed as part of pulmonary function tests. It is also often written as DLCO/VA (diffusing capacity per liter of lung volume) and is an index of the efficiency of alveolar transfer of carbon monoxide. Interp...
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Cannonball metastasis (mnemonic)

Cannonball metastases refer to multiple large, well-circumscribed, round pulmonary metastases. The primary tumors for these lesions can be remembered with the help of this mnemonic: CRESP Mnemonic C: choriocarcinoma R: renal cell carcinoma E: endometrial carcinoma S: synovial sarcoma P: p...
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Thymus protocol (MRI)

Thymic MRI is a targeted mediastinal imaging protcol performed mainly to distinguish surgical from nonsurgical thymic lesions (eg. thymic hyperplasia, thymic cysts, and lymphoma). Note: This article is intended to outline some general principles of protocol design. The specifics will vary depen...
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Hypomyopathic dermatomyositis

Hypomyopathic dermatomyositis is a rare systemic autoimmune disorder of the skin with little to no muscle involvement. It makes up <5% of all dermatomyositis diagnoses.  Epidemiology The incidence is 2 in 1,000,000 ref and it typically affects women more than man at a 2:1 1. Clinical presenta...
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Ring shadow (chest)

Ring shadows on chest x-ray are classically associated with cystic bronchiectasis 1,2 but the term has also been used to describe a normal bronchus imaged end-on 3. 
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Lymphangioleiomyomatosis diagnostic criteria (mnemonic)

A mnemonic to remember the diagnostic criteria of lymphangioleiomyomatosis (LAM) is: THRALL PVC ​Mnemonic T: tuberous sclerosis H: HRCT characteristic or compatible lung findings of LAM RA: renal angiomyolipoma L: lymphatic malformations L: lung biopsy-proven LAM   P: pneumothorax ​V: V...
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Bacillus Calmette–Guérin (BCG) vaccine

The bacillus Calmette–Guérin (BCG) vaccine is the only vaccine available for Mycobacterium tuberculosis and despite its global use for 90 years, with proven efficacy and a good safety record, has well-known limitations. It provides only limited protection against pulmonary tuberculosis. The vac...
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Coal mine dust lung disease

Coal mine dust lung disease encompasses a number of occupational lung diseases 1,2: coal workers' pneumoconiosis (CWP) mixed dust pneumoconiosis silicosis dust-related diffuse fibrosis chronic obstructive pulmonary disease (COPD)
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Skinfold artifact

The skinfold artifact can mimic a pneumothorax on chest radiography and is caused by the added density of a skin fold against the image. It appears as a broad opacity laterally, outlined by a lucent line (Mach band effect) 2. Radiographic features Plain radiograph The following features may h...
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Giant cell carcinoma of the lung

Giant cell carcinomas of the lung are a rare type of non-small cell lung carcinomas (NSCLC) classified under sarcomatoid carcinomas of the lungs. Epidemiology They represent less than 0.5% of all NSCLC 2. There is a recognized association with smoking 1.  Clinical presentation Symptoms are n...
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Bronchial stenosis

Bronchial stenosis, or bronchial strictures, are descriptive terms to denote regions of focal narrowing involving the bronchi. They can arise from a wide variety of etiologies. Pathology Etiology It can arise from a large range of etiological factors, which include: tracheobronchial malignan...
Article

Antineutrophil cytoplasmic antibody

Antineutrophil cytoplasmic antibodies (ANCAs) are a heterogenous class of IgG autoantibodies raised against the cellular contents of neutrophils, monocytes and endothelial cells 1. Under indirect immunofluorescence (IIF) microscopy, three ANCA staining patterns are observed, based on the varying...
Article

Pembrolizumab-induced sarcoid-like reaction

Pembrolizumab-induced sarcoid-like reaction is a recently (c.2019) reported phenomenon which has been associated with the use of the programmed cell death protein 1 (PD1) inhibitor pembrolizumab. It could be mistaken for metastatic disease in some situations. See also  drug induced lung diseas...
Article

Diffuse ground-glass opacification

Diffuse or widespread ground-glass opacification/opacity can either manifest as diffuse ground-glass nodules or amorphous areas of diffuse ground glass. They can carry a wide differential diagnosis 1-3: diffuse alveolar disease hydrostatic pulmonary edema acute respiratory distress syndrome ...
Article

Mushroom worker's lung

Mushroom worker’s disease is a hypersensitivity pneumonitis caused by the occupational exposure of allergenic fungal spores and compost associated with the inhalation of organic dust from mushroom composting and spawning. Clinical presentation It presents as an acute pulmonary illness with cou...
Article

Tracheal leiomyoma

Tracheal leiomyoma is a form of a benign tracheal tumor. Epidemiology They are thought to account for around 1% of all tracheal tumors.  Clinical presentation Presentation depends on tumor location and size with some reports suggesting patients becoming symptomatic when tumor obstructs more ...
Article

Tuberculous pleuritis

Tuberculous pleuritis is a form of pleural tuberculosis and refers to inflammation of the pleura due to infection by Mycobacterium tuberculosis. It is considered the second most common form of extra-pulmonary tuberculosis 1. It may progress into a tuberculous empyema. Epidemiology It may be co...
Article

Maple bark disease

Maple bark disease, also known as maple bark stripper’s disease, is a rare hypersensitivity pneumonitis caused by the allergenic fungal spores of Cryptostroma corticale. The fungus causes sooty bark disease under the bark of maples and sycamore trees. The first formal clinical accounts of the d...
Article

Cheese workers' lung

Cheese workers' lung is a rare hypersensitivity pneumonitis due to the exposure of certain Penicillium species seen in people who work with mouldy cheese. Clinical presentation It can present as an acute pulmonary illness with fever and dyspnea. Clinical features are consistent with other form...
Article

Interstitial pneumonia with autoimmune features

Interstitial pneumonia with autoimmune features (IPAF) is a term given for patients with interstitial lung disease (ILD) who show some features related to autoimmunity but without meeting full criteria for a defined connective tissue disease. The term is based on the 2015 European Respiratory S...
Article

Traversal of lung fissures

Only a small number of pulmonary diseases are known to directly traverse the lung fissures such that the lung pathology extends from one lobe via the interlobar fissure into an adjacent lobe 1. The finding is most commonly due to primary malignancy, however, some infections are also known to do ...
Article

Mediastinitis

Mediastinitis by definition refers to inflammation of the connective tissues and fat within the mediastinum.  In clinical practice; mediastinitis is generally used to refer to acute mediastinitis, resulting from bacterial infection within the mediastinum. This is considered a serious and potent...
Article

Sternal dehiscence

Sternal dehiscence of the median sternotomy closure is an infrequent post sternotomy complication. It may be latent or difficult to detect clinically, or it may be sudden and very obvious. It may lead to sternal non-union. It may or may not be complicated by infection. Epidemiology It may occu...
Article

Herder risk model

British Thoracic Society (BTS) guidelines for pulmonary nodules1 recommend the application of the Herder risk model in predicting malignancy in pulmonary nodules. The Herder model 2 predicts the risk of malignancy in solid pulmonary nodules using patient characteristics, nodules characteristics...
Article

HIV associated pulmonary arterial hypertension

HIV associated pulmonary arterial hypertension (HIV-PAH) is a specific form of pulmonary arterial hypertension associated with HIV. Epidemiology It is thought that approximately 0.5% of patients with HIV infection can develop moderate to severe pulmonary arterial hypertension. This is consider...
Article

Bacterial pneumonia

Bacterial (pyogenic) pneumonia is common and is a major cause of morbidity and mortality globally. Clinical presentation Bacterial pneumonia has symptoms similar to other pneumonia. When a productive cough is present, purulent or blood-stained sputum may indicate bacterial pneumonia ref. Path...
Article

Lepidic growth

Lepidic growth is a pathological term referring to a pattern of cell proliferation along the lining of the alveolar structures of the lung as is seen in a subset of lung tumors 1. History and etymology ‘lepidic’ was coined by the English pathologist John George Adam (1862-1926) whilst at McGil...
Article

Lower lobe fibrosis (mnemonic)

A mnemonic to remember differentials causing lower lobe fibrosis or predominant lower lobe fibrosis. SAB-IPM IPAS-BM Mnemonic SAB-IPM S: systemic sclerosis and other connective tissue diseases (e.g. rheumatoid arthritis) A: aspiration, alpha-1 antitrypsin deficiency, asbestosis B: bronchi...
Article

Ring around artery sign

The ring around artery sign refers to a (semi-) circular radiolucency surrounding the right pulmonary artery caused by mediastinal air in the case of pneumomediastinum 1-3. The sign was originally described on lateral chest radiographs 1-4 but can be equally appreciated on sagittal multiplanar ...
Article

Pulmonary gangrene

Pulmonary gangrene can be a complication of necrotizing pneumonia and often represents a final stage in a continuum of progressive devitalisation of pulmonary parenchyma and is characterized by sloughing of a pulmonary segment or lobe. Pathology In most instances is occurs as a complication of...

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