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.

1,251 results found
Article

2011 revision of usual interstitial pneumonia pattern: diagnostic HRCT criteria

As a part of international evidence based guidelines adopted by collaborative effort of American Thoracic Society, the European Respiratory Society, the Japanese Respiratory Society and the Latin American Thoracic association,  specific diagnostic HRCT criteria for usual interstitial pneumonia (...
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AAST injury scoring scales

The American Association for the Surgery of Trauma (AAST) injury scoring scales are the most widely accepted and used system of classifying and categorising traumatic injuries. Injury grade reflects severity, guides management, and aids in prognosis. At the time of writing (mid 2016), 32 differe...
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Aberrant left pulmonary artery

Aberrant left pulmonary artery, also known as pulmonary sling, represents an anatomical variant characterised by the left pulmonary artery arising from the right pulmonary artery and passing above the right main bronchus and in between the trachea and oesophagus to reach the left lung. It may le...
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Aberrant right subclavian artery

Aberrant right subclavian arteries (ARSA), also known as arteria lusoria, are the commonest of the aortic arch anomalies 2.  Epidemiology The estimated incidence is 0.5-2%. Clinical presentation They are often asymptomatic, but around 10% of people may complain of tracheo-oesophageal symptom...
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Abscess

Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1: central core comprised of necrotic inflammatory cells and local tissue peripheral halo of viable neutrophils surrounded by a 'capsule' with dilated blood vessels a...
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Accessory fissures of the lung

Accessory fissures of the lung usually occur at the borders of bronchopulmonary segments. They are common normal variants but are less commonly seen on imaging.  Some of the more common accessory fissure include 1: azygos fissure: most commonly seen accessory fissure inferior accessory fissur...
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Accessory hemiazygos vein

The accessory (or superior) hemiazygos vein forms part of the azygos system and along with the hemiazygos vein, it is partially analogous to the right-sided azygos vein. It drains the left superior hemithorax.  Gross anatomy Origin and course The accessory hemiazygos vein is formed by the con...
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Achalasia

Achalasia (primary achalasia) refers to a failure of organised oesophageal peristalsis with an impaired relaxation of the lower oesophageal sphincter (LOS), resulting in often marked dilatation of the oesophagus and food stasis. Obstruction of the distal oesophagus (often due to tumour) has been...
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Acinic cell carcinoma of the lung

Acinic cell carcinoma of the lung (also known as a Fechner tumour) is a type of lung carcinoma of the salivary gland type. It is extremely rare especially when it presents in the form of a primary acinic cell carcinoma. Pathology Histologically, they are comprised of clear cells with abundant ...
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Acute airspace opacification with lymphadenopathy: differential diagnosis

Acute airspace opacification with lymphadenopathy is a subset of the differential diagnosis for generalised airspace opacification and includes: post obstructive causes (usually chronic, but 'new' changes can occur) primary lung cancer pulmonary metastases lymphoma / leukaemia infection p...
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Acute aspiration pneumonitis

Acute aspiration pneumonitis refer to a form aspiration pneumonia where the time of onset is rapid. Radiographic features Plain radiograph / CT Features can be variable and can range from a pulmonary oedema pattern to areas of consolidation. These changes may have a gravity dependant distribu...
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Acute bilateral airspace opacification (differential)

Acute bilateral airspace opacification is a subset of the larger differential diagnosis for airspace opacification. An exhaustive list of all possible causes of acute bilateral airspace opacities is long, but a useful way to consider the huge list is by the material within the airways: ...
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Acute coronary syndrome

Acute coronary syndrome (ACS) is a group of cardiac diagnoses along a spectrum of severity due to the interruption of coronary blood flow to the myocardium, which in decreasing severity are: ST elevation myocardial infarction (STEMI) non-ST elevation myocardial infarction (non-STEMI) unstable...
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Acute eosinophilic pneumonia

Acute eosinophilic pneumonia (AEP) is a type of eosinophilic lung disease. It is diagnosed when the following combination clinical and radiographic findings occur 5,7: febrile illness of less than five days duration hypoxaemia diffuse alveolar or mixed alveolar-interstitial opacities on chest...
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Acute hypersensitivity pneumonitis

Acute hypersensitivity pneumonitis (AHP) refers to the acute form of hypersensitivity pneumonitis although this classification system has recently been challenged 4. For a general discussion of the condition, refer to the parent article. Clinical presentation Fever, chills, myalgia, headaches,...
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Acute interstitial pneumonitis

Acute interstitial pneumonitis (AIP), also know as Hamman-Rich syndrome is a rapidly progressive non infectious interstitial lung disease of unknown aetiology. It is considered the only acute process of the idiopathic interstitial pneumonias. Epidemiology AIP (without an underlying cause) tend...
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Acute lung transplant rejection

Acute lung transplant rejection is one of the post lung transplant complications. Histologically, it is defined as perivascular or peribronchiolar mononuclear inflammation and may affect up to 55% of lung transplant recipients within the first year after a transplant 2.  Epidemiology It can oc...
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Acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a form of acute lung injury (ALI) and occurs as a result of severe pulmonary injury that cause alveolar damage heterogeneously throughout the lung. It can either result from a direct pulmonary source or as a response to systemic injury. Pathology L...
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Acute right heart syndrome

Acute right heart syndrome (ARHS) is defined as a sudden deterioration in right ventricular (RV) function and failure of the RV to deliver adequate blood flow to the pulmonary circulation. This can result in systemic hypoperfusion. Pathology ARHS can occur in several settings 1 in the setting...
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Acute unilateral airspace opacification (differential)

Acute unilateral airspace opacification is a subset of the differential diagnosis for airspace opacification.  The exhaustive list of all possible causes would be huge, but a useful framework includes : pus, i.e. infection bacterial pneumonia fungal pneumonia viral pneumoni...
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Adenocarcinoma in situ of lung

Adenocarcinoma in situ (AIS) of lung refers to a relatively new entity for a pre invasive lesion in the lung. This entity partly replaces the non invasive end of the previous term bronchoalveolar carcinoma. AIS is defined as a localised adenocarcinoma of <3 cm, that exhibits a lepidic pattern...
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Adenocarcinoma in situ, minimally invasive adenocarcinoma and invasive adenocarcinoma of lung

Adenocarcinoma in situ, minimally invasive adenocarcinoma and invasive adenocarincoma of lung are relatively new classification entities which now replaces the now defunct term bronchoalveolar carcinoma (BAC). In 2011 the International Association for the Study of Lung Cancer and other societie...
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Adenocarcinoma of the lung

Adenocarcinoma of the lung is one of the non-small cell carcinomas of the lung and is a malignant tumour with glandular differentiation or mucin production. This tumour exhibits various patterns and degrees of differentiation, including lepidic, acinar, papillary, micropapillary and solid with m...
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Adenoid cystic carcinoma

Adenoid cystic carcinoma (ACC) are a rare histological subtype of adenocarcinoma. Pathology ACCs are generally considered low grade 4. The tumors have notable tendency for perineural spread. Location They have wide distribution and mainly occur in relation to the airways, lacrimal glands and...
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Adenoid cystic carcinoma of lung

Adenoid cystic carcinoma (ACC) of lungs are a type of non small cell lung cancer. They are classified under lung carcinomas of the salivary gland type. Primary occurrance in the lung parenchyma is rare and in the thorax, they more commonly occur as adenoid cystic carcinoma of the tracheo-bronchi...
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Adenoid cystic carcinoma of the tracheobronchial tree

Adenoid cystic carcinomas of the tracheobronchial tree are a type a low-grade tracheal tumour. They are considered the second most common primary tumour of the trachea. Epidemiology They are usually first recognized in patients in their 40s. There is no recognised gender predilection. Clinica...
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Adenosquamous carcinoma of lung

Adenosquamous carcinoma (ASC) of the lung is a rare type of non small cell lung cancer. Epidemiology It is thought to constituting 0.4-4% of cases non small cell lung cancer. Pathology The definition of adenosquamous carcinoma indicates a carcinoma showing components of adenocarcinoma and sq...
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Adult chest radiograph common exam pathology

Adult chest radiograph common exam pathology is essential to consider in the build up to radiology exams.  The list of potential diagnoses is apparently endless, but there are some favorites that seem to appear with more frequency. When dealing with the adult chest radiograph in the exam settin...
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Adult chest radiograph in the exam setting

A chest radiograph in the exam setting may contain a vast variety of pathology. However, consider the history and correlate the likely diagnoses that may be demonstrated on film. Furthermore, check your review areas to ensure that the abnormality isn't at the corner of the film. Locating pathol...
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Adult chest radiograph pathology checklist

The adult chest radiograph pathology checklist is just a pathology checklist of things not to miss when reviewing a chest radiograph, especially in the exam setting. standard review areas apices retrocardiac area hilar regions below the diaphragm right descending pulmonary artery (like a l...
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Adult chest radiograph set-pieces

There are a number of adult chest radiograph set-pieces. These are based on common patterns of disease that are seen on chest radiographs. Make sure that you have relevant differentials for these appearances and a quick aural set-piece for them when they come up. Pulmonary parenchyma lobar col...
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Aflatoxins

Aflatoxins are naturally occuring mycotoxins that are produced by Aspergillus species, especially Aspergillus flavus. They are acutely toxic and carcinogenic. Acute exposure High-level aflatoxin exposure can result acute aflatoxicosis with acute hepatic necrosis, resulting in cirrhosis, and po...
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Agenesis of the diaphragm

Agenesis of the diaphragm is a congenital diaphragmatic developmental anomaly where all or part of diaphragm fails to form. It can sometimes be thought of as an extreme form congenital diaphragmatic herniation 1. Pathology The agenesis can either be unilateral or bilateral. Herniation of abdom...
Article

AIDS defining illness

AIDS defining illnesses are conditions that in the setting of a HIV infection confirm the diagnosis of AIDS, and do not commonly occur in immunocompetent individuals 2. According to the CDC surveillance case definition 1, they are: Infectious bacterial infections: multiple or recurrent candid...
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AIDS-related pulmonary lymphoma

AIDS related pulmonary lymphoma (ARPL) is classified as a distinct form of pulmonary lymphoma. Pulmonary involvement is a common extranodal site in AIDS-related NHL. Pathology ARPL is typically a high-grade B-cell non-Hodgkin's lymphoma and the majority of patients have advanced HIV infection,...
Article

Air bronchogram

Air bronchogram refers to the phenomenon of air-filled bronchi (dark) being made visible by the opacification of surrounding alveoli (grey/white). It is almost always caused by a pathologic airspace/alveolar process, in which something other than air fills the alveoli. Air bronchograms will not ...
Article

Air crescent sign

An air crescent sign describes the crescent of air that can be seen in invasive aspergillosis, semi-invasive aspergillosis or other processes that cause pulmonary necrosis. It usually heralds recovery and is the result of increased granulocyte activity. In angioinvasive fungal infection, the no...
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Air space disease

Air space disease, or alveolar lung disease, is a process in which there is a filling of the lung's alveoli / acini. Radiographic features lobar or segmental distribution poorly marginated airspace nodules tendency to coalesce air bronchograms bat's wing (but...
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Air space nodule

An air space nodule is a small (few millimeters to 1 cm), ill defined, nodular opacity and often centrilobular in location seen in patients with air space disease. It represents focal area of consolidation or peribronchiolar inflammation and indicates endobronchial spread of disease. 
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Air space opacification

Air space opacification is a descriptive term that refers to filling of the pulmonary tree with material that attenuates x-rays more than the surrounding lung parenchyma.  It is one of the many patterns of lung opacification and is equivalent to the pathological diagnosis of pulmonary consolidat...
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Air space opacities

The differential for air space opacities is extensive, and needs to be interpreted in context of chronicity (previous imaging) and clinical context. It is therefore useful to divide airspace opacities as follows: acute airspace opacities with lymph node enlargement acute airspace opacities: un...
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Air trapping

Air trapping in chest imaging refers to retention of excess gas (“air”) in all or part of the lung, especially during expiration, either as a result of complete or partial airway obstruction or as a result of local abnormalities in pulmonary compliance. It may also sometimes be observed in norma...
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Airspace nodules

Airspace nodules are irregularly marginated nodular opacities with air bronchograms that tend to measure 8 mm in diameter. They are quite separate from pulmonary nodules that range in size, are homogeneous and well-defined (being surrounded by normal lung).
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Airway foreign bodies in children

Airway foreign bodies in children are potentially fatal and proper recognition is important because delayed diagnosis is common.  Epidemiology Children under the age of four years are at increased risk of foreign body (FB) aspiration with a slight male predominance 1.  Clinical presentation ...
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Airway invasive aspergillosis

Airway invasive aspergillosis refers to a form of invasive aspergillosis.  Epidemiology It usually occurs in immunocompromised neutropenic patients and in patients with AIDS. Aspergillosis affecting the airways as the major or only feature of invasive disease is uncommon and is thought to occu...
Article

All trans retinoic acid syndrome

All trans retinoic acid (ATRA) syndrome (more recently known as differentiation syndrome (DS)8) is a condition that can occur with patients with acute promyelocytic leukemia who are on therapeutic all-trans-retinoic acid (ATRA). All-trans-retinoic acid (ATRA) is a normal constituent of plasma. ...
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Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is at one end of the spectrum of disease caused by pulmonary aspergillosis and can be classified as an eosinophilic lung disease 2-4. Epidemiology This entity is seen is almost only encountered in patients with longstanding asthma, and only occasi...
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Alpha-1-antitrypsin deficiency

Alpha-1-antitrypsin (AAT) deficiency is a hereditary metabolic disorder. It is the most common metabolic liver disease in children and results in the unopposed action of neutrophil elastase and subsequent severe basal emphysema and respiratory symptoms. Clinical presentation The classic presen...
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Alveolar sarcoidosis

Alveolar sarcoidosis is an atypical pulmonary manifestation of sarcoidosis.  Epidemiology This appearance may be present in around 4% 1 of those with pulmonary sarcoidosis on plain film and up to 15% 2 of those on CT. Pathology This appearance is thought to result from aggregation of large n...
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American Thoracic Society criteria for histopathological diagnosis of usual interstitial pneumonia

American Thoracic Society (ATS) criteria for histopathological diagnosis of usual interstitial pneumonia​ (UIP) are as follows:  advanced subpleural or paraseptal fibrosis +/- honeycombing  patchy temporally heterogeneous fibrosis fibroblastic foci absence of features against UIP inflammato...
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Amiodarone lung

Amiodarone lung is an interstitial lung disease seen in patients being administered amiodarone, and can manifest in a number of histopathologic patterns. Epidemiology The reported prevalence of pulmonary toxicity in the patients receiving amiodarone ranges from 2-18% 8. Patients are usually e...
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Amniotic fluid embolism to lung

Amniotic fluid emboli (AFE) is a special type of pulmonary embolism where the embolus is comprised of amniotic fluid. It can be a highly fatal complication of pregnancy, with an 80% maternal mortality rate.  Epidemiology It is thought to complicate 1/8000-80,000 pregnancies. Clinical presenta...
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Amyloidosis

Amyloidosis is a heterogeneous disease or even considered a constellation of diseases resulting in a deposition relatively similar proteins. It has many causes and can affect essentially any organ system. Epidemiology  There may be male predilection. Typically affects middle aged individuals a...
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Angioinvasive aspergillosis

Angioinvasive aspergillosis is the most severe and aggressive form of invasive aspergillosis. It is a life threatening condition that requires prompt treatment. Fortunately, it is not seen in the general population and only occurs in profoundly immunocompromised patients.  Epidemiology Angioin...
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Angiosarcoma involving the lung

Angiosarcoma involving the lung includes metastatic angiosarcoma to lung 1 -  commoner usual primary sites include the heart and breast 2. primary pulmonary angiosarcoma - very rare See also angiosarcoma - general article
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Anterior bronchus sign

The anterior bronchus sign refers to the appearance of the anterior segmental bronchus of the upper lobes as seen on a frontal chest radiograph. Normal anatomy The anterior segment bronchus of the upper lobes courses anteriorly and laterally. When the orientation is predominantly anteriorly t...
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Anterior junction line

The anterior junction (junctional) line is a feature of frontal chest x-rays and chest CTs. It is a result of the parietal and visceral pleura meeting anteromedially. It normally contains a small amount of fat but can form a stripe of variable thickness if there is a lot of fat present or by the...
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Anterior mediastinal germ cell tumours

Germ cell tumours are one of the causes of anterior mediastinal mass, and any of the germ cell histologies may be identified. They can therefore be divided histologically into: seminoma non-seminomatous germ cell tumours (NSGCT) embryonal cell carcinoma choriocarcinoma yolk sac tumour tera...
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Anterior mediastinal mass in the exam

Getting a film with an anterior mediastinal mass in the exam is one of the many exam set-pieces that can be prepared for. The film goes up and after a couple of seconds pause, you need to start talking: CXR There is a left sided mediastinal mass that makes obtuse angles with the mediastinal c...
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Anterior mediastinum

The anterior mediastinum is that portion of the mediastinum anterior to the pericardium and below the thoracic plane. It forms the anterior part of the inferior division of the mediastinum, and contains the thymus, lymph nodes, and may contain the portions of a retrosternal thyroid. Related pa...
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Anterosuperior mediastinal mass (mnemonic)

The causes of an anterosuperior mediastinal mass can be remembered by using the mnemonic: 5 T's Mnemonic T: thymus-see primary tumours of the thymus T: thyroid-see primary tumours of the thyroid T: thoracic aorta-see causes of a dilated thoracic aorta T: terrible lymphoma T: teratoma and ...
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Anti-neutrophil cytoplasmic antibody associated vasculitides

Anti-neutrophil cytoplasmic antibody associated vasculitides refer to a group of heterogeneous autoimmune diseases characterized by necrotising vasculitides and positive anti-neutrophil antibody titres. They are reactive to either proteinase-3 (PR3-ANCA) - cANCA or myeloperoxidase (MPO-ANCA) - p...
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Anti-synthetase syndrome

Anti-synthetase syndrome (ASS) is a systemic, inflammatory, autoimmune disease that is characterised by inflammatory myositis, polyarthritis associated with interstitial lung disease (ILD) and anti-synthetase autoantibodies. Pathology ASS can result from autoantibodies to eight of the aminoacy...
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Antiphospholipid syndrome

Antiphospholipid syndrome is a systemic autoimmune disorder. It is usually defined as the clinical complex of vascular occlusion and ischaemic events occurring in patients who have circulating antiphospholipid antibodies. Pathology Patients have circulating antiphospholipid antibodies cross-re...
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Antiphospholipid syndrome: pulmonary manifestations

Pulmonary involvement in antiphospholipid syndrome is one of the most frequent artial complications of antiphopholipid syndrome.  Pathology It is essentially related pulmonary arterial microthrombosis although a wide spectrum of conditions can result which include 3-5 pulmonary thromboembolic...
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Aortic arch

The aortic arch represents the direct continuation of the ascending aorta and represents a key area for a review of normal variant anatomy and a wide range of pathological processes that range from congenital anomalies to traumatic injury. Summary origin: continuation of the ascending aorta at...
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Aortic dissection

Aortic dissection is one of the acute aortic syndromes and a type of arterial dissection. It occurs when blood enters the medial layer of the aortic wall through a tear or penetrating ulcer in the intima and tracks along the media, forming a second blood-filled channel within the wall.  Epidemi...
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Aortic hiatus

The aortic hiatus is one the three major apertures through the diaphragm and lies at the level of T12. Strictly speaking, it is not a real aperture in the diaphragm, but an osseoaponeurotic opening between it and the vertebral column.  The hiatus is situated slightly to the left of the midline ...
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Aortic intramural haematoma

Aortic intramural haematoma (IMH) is an atypical form of aortic dissection due to haemorrhage into the wall from the vasa vasorum without an intimal tear. Epidemiology Typically aortic intramural haematomas are seen in older hypertensive patients. The same condition may also develop as a resul...
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Aortic nipple

An aortic nipple is seen in about 10% of PA chest x-rays on the lateral surface of the aortic arch/aortic knob. It represents the left superior intercostal vein. When prominent, superior vena cava obstruction should be considered (the left superior intercostal vein might be a collateral pathway).
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Aortic-pulmonary stripe

The aortic-pulmonary stripe is an uncommon feature of frontal chest x-rays and was first described by Keats in 1972 1. It is formed by the interface of the pleural surface of the anterior segment of the left upper lobe contacting the mediastinal fat that is anterolateral to the pulmonary trunk ...
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Aortopulmonary septal defect

Aortopulmonary septal defect (APSD), also known as aortopulmonary window (APW), is a congenital anomaly where there is an abnormal communication between the proximal aorta and the main pulmonary artery in the presence of separate aortic and pulmonary valves. Terminology APSD should not be conf...
Article

Aortopulmonary window

The aortopulmonary (aortic-pulmonary or AP) window is a radiological mediastinal space seen on frontal chest x-rays. Terminology The term "aortopulmonary window" can also refer to a rare form of congenital heart disease, where there is an opening between the aorta and the pulmonary t...
Article

Apical lung disease (mnemonic)

A handy mnemonic to remember common apical lung disease is: SET CARP or CARPETS Mnemonic S: sarcoidosis E: eosinophilic pneumonia T: tuberculosis C: cystic fibrosis A: ankylosing spondylitis R: radiation pneumonitis P: pneumoconiosis
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Apical pleural cap

Apical pleural cap refers to a curved density at the lung apex seen on chest radiograph. Epidemiology The frequency of apical pleural thickening increases with age 3. Pathology It arises from a number of causes: pleural thickening/scarring idiopathic: often a chronic ischaemic aetiology is...
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Apical zone

The apical zone is one of the four chest radiograph zones and an important location for missed diagnoses when reporting a frontal chest radiograph and makes up one of the "check areas". It is sometimes thought of as a subdivision of the upper zone.  Radiographic appearance Plain radi...
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Approach to a solitary pulmonary nodule

A solitary pulmonary nodule, according to the Nomenclature Committee of the Fleischner Society, defined as a rounded opacity, well or poorly defined on a conventional radiograph, measuring up to 3 cm in diameter and is not associated with lymphadenopathy, atelectasis, or pneumonia. Several radi...
Article

Approach to diffuse pulmonary nodules on HRCT

A number of differentials must be kept in mind while approaching diffuse pulmonary nodules. Interpretation is easier if nodules are the only abnormality. These differentials can be narrowed down based on the several criteria: Based on appearance  miliary nodules   miliary tuberculosis silic...
Article

Asbestos

Asbestos is a set of six naturally occurring silicate minerals from mixture of calcium magnesium, iron, and sodium exploited commercially for their desirable physical properties, particularly their resistance to heat and burning. They all form thin elongated fibrous crystals, and can be manufact...
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Asbestos body

An asbestos body is a histological finding in interstitial lung disease that is suggestive of significant occupational asbestos exposure. They are usually identified following a parenchymal lung biopsy 3. Macrophage ingestion of the asbestos fibres triggers a fibrogenic response via the release...
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Asbestos related benign pleural disease

Asbestos related benign pleural disease forms a large part of asbestos related lung changes. The spectrum comprises of: pleural effusions: benign-asbestos induced pleural effusions can be associated with functional impairment usually occur within 10 years of exposure but can also develop muc...
Article

Asbestos related diseases

Asbestos related disease, in particular affecting the lung, comprise of a broad spectrum of entities related to the inhalational exposure to asbestos fibres. They can be divided into benign and malignant changes 1-3. Benign pleural and parenchymal lung disease asbestos related benign pleural d...
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Asbestosis

Asbestosis refers to later development of diffuse interstitial fibrosis secondary to asbestos fibre inhalation and should not be confused with other asbestos related diseases. Epidemiology Asbestosis typically occurs 10-15 years following the commencement of exposure to asbestos and is dose re...
Article

Ascariasis

Ascariasis is due to infection with the Ascaris lumbricoides adult worm, and typically presents with gastrointestinal or pulmonary symptoms, depending on the stage of development.   Epidemiology Ascaris lumbricoides is widely distributed in tropical and subtropical regions and in other humid a...
Article

Ascending aorta dilatation

Dilatation of the ascending aorta is a common finding in the elderly but unusual in younger patients. Pathology In adults, an ascending aortic diameter greater than 4 cm is considered to indicate dilatation 4. Aneurysmal dilatation is considered when the ascending aortic diameter reaches or ex...
Article

Ascending aortic aneurysm

Ascending aortic aneurysms are the most common subtype of thoracic aortic aneurysms, and may be true or false injuries.  Epidemiology Ascending aortic aneurysms represent 60% of thoracic aortic aneurysms.  Clinical presentation Typically ascending aortic aneurysms are an incidental finding a...
Article

Askin tumour

The original description of the Askin tumour (by Askin and Rosai in 1979 1), and many studies following it have led to a great deal of confusion. Until recently it has been considered a separate entity or as a type of peripheral primitive neuroectodermal tumour, usually of the chest wall. Recen...
Article

Aspergilloma

Aspergillomas are mass-like fungus balls that are typically composed of Aspergillus fumigatus, and are a non-invasive form of pulmonary aspergillosis. Terminology Although the term mycetoma is frequently used to describe these fungal balls, it is an incorrect term to use 5-6. Epidemiology As...
Article

Aspergillus

Aspergillus is a fungal genus consisting of approximately 180 species.  It is a ubiquitous fungus found frequently in urban areas especially in decomposing organic matter or water damaged walls and ceilings. Only a few Aspergillus species are associated with human disease.  Aspergillus species ...
Article

Aspergillus clavatus

Aspergillus clavatus is one of the species of Aspergillus that can cause pathology in humans. It is allergenic and causes a hypersensitivity pneumonitis called malt-workers lung. See also Aspergillus Aspergillus fumigatus Aspergillus flavus Aspergillus clavatus
Article

Aspergillus flavus

Aspergillus flavus is a fungus and one of the species of Aspergillus that is common in the environment and responsible for pathology in humans. It is the second most common cause of pulmonary aspergillosis (after Aspergillus fumigatus) and can additionally cause corneal, otomycotic, and nasoorb...
Article

Aspergillus fumigatus

Aspergillus fumigatus is a fungus of the genus Aspergillus, and is one of the most common Aspergillus species to cause disease in immuno-compromised individuals. A. fumigatus is a saprotroph (an organism that gets its energy from non-living organic matter) that is widespread in nature, typicall...
Article

Aspiration bronchiolitis

Aspiration bronchiolitis, or diffuse aspiration bronchiolitis, is a condition characterised by a chronic inflammation of bronchioles caused by recurrent aspiration of foreign particles. Clinical presentation The onset of aspiration bronchiolitis can be more insidious than aspiration pneumonia,...

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