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.

1,430 results found
Article

Shred sign (lungs)

Shred sign is a static sonographic sign observed in lung consolidation. The deeper border of consolidated lung tissue that makes contact with the aerated lung is shredded and irregular. This sign is not seen in massive translobar consolidation in which it is more difficult to appreciate the deep...
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Shrinking lung syndrome

Shrinking lung syndrome (SLS) refers to a rare complication of systemic lupus erythematosus (SLE), and is characterised by: unexplained dyspnoea restrictive pattern on pulmonary function tests elevated hemidiaphragm Epidemiology As with SLE in general, it is thought to carry a increased fem...
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Sickle cell disease

Sickle cell disease (SCD) is a hereditary (autosomal recessive) condition resulting in the formation of abnormal haemoglobin (a haemoglobinopathy), which manifests as multisystem ischaemia and infarction, as well as haemolytic anaemia.  Epidemiology There is no recognised gender predilection. ...
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Sickle cell disease (acute chest syndrome)

Acute chest syndrome (ACS) in sickle cell disease is a leading thoracic complication as well as leading cause of mortality in those affected by sickle cell disease. The diagnosis is made on the combination of new pulmonary opacity on chest x-ray with at least one new clinical symptom or sign.  ...
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Sickle cell disease (chronic lung disease)

Chronic lung disease in sickle cell anaemia is one of the pulmonary complications that can occur with sickle cell disease. For a general discussion of sickle cell disease, please refer to sickle cell disease. Clinical presentation Patients often present slow progressive decline in pulmonary f...
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Signet ring sign

The signet ring sign is seen in bronchiectasis when the dilated bronchus and accompanying pulmonary artery branch are seen in cross-section. The bronchus and artery should be the same size, whereas in bronchiectasis, the bronchus is markedly dilated. The signet ring analogy has also been applie...
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Signs of pulmonary embolus on chest radiography

There are several described signs of pulmonary embolus on chest radiography which are suggestive of this diagnosis. None are pathognomonic and need to be interpreted with caution with close regard to the clinical presentation. Chang sign Fleischner sign Hampton hump (strictly a sign of pulmon...
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Silhouette sign (x-rays)

Silhouette sign is somewhat of a misnomer and in the true sense actually denotes the loss of a silhouette, thus, it is sometimes also known as loss of silhouette sign or loss of outline sign 4.  The differential attenuation of x-ray photons by two adjacent structures defines the silhouette, e.g...
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Silicosis

Silicosis is a fibrotic pneumoconiosis caused by the inhalation of fine particles of crystalline silicon dioxide (silica). Occupations such as mining, quarrying, and tunneling are associated with silicosis. The disease occurs in two clinical forms that are subdivided by their temporal relations...
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Siltzbach sarcoidosis chest radiographic staging system

Siltzbach system is a chest radiographic staging method for sarcoidosis. stage 0: normal chest radigraph: 10% at time of diagnosis stage I: lymph node enlargement: 50% at time of diagnosis stage II: lymph node enlargement and pulmonary opacities: 30% at time of diagnosis stage III: pulmonary...
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Single pleural based mass (differential)

The differential for a single pleural mass is essentially the same as that for multiple pleural masses with the addition of a few entities.  tumours pleural tumours solitary fibrous tumour of the pleura (pleural fibroma) mesothelioma localised mediastinal malignant mesothelioma metastatic...
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Sinusoid sign (ultrasound)

The sinusoid sign is a dynamic sonographic sign in M-mode describing the movement line representing the lung towards the pleural line which is displayed as a sinusoidal pattern. Similar to the quad sign, this sign has a high sensitivity and specificity for pleural effusion, which is anechoic in ...
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Situs classification

Situs classification can be a daunting topic, but it falls into three main groups : situs solitus: the normal configuration of thoracic and abdominal organs situs inversus: mirror image of normal situs ambiguus: an intermediate configuration with duplication (isomerism) Situs is best thought...
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Situs inversus

Situs inversus, short form of the Latin “situs inversus viscerum”, is a term used to describe the inverted position of chest and abdominal organs. It is called situs inversus totalis when there is a total transposition of abdominal and thoracic viscera (mirror image of internal organs normal pos...
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Situs solitus

Situs solitus refers to the normal position of the thoracic and abdominal organs. Radiographic features Plain radiograph On plain radiograph, careful attention should be directed at the location of the aortic arch, gastric fundus, cardiac apex, pulmonary fissures and the branching pattern of ...
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Sjögren syndrome (thoracic manifestations)

Thoracic manifestations of Sjögren syndrome are common and sometimes detected before the syndrome diagnosis. For a broad discussion on the syndrome and its typical lymphocytic infiltration of the exocrine glands, please refer to the main article on Sjögren syndrome.  Clinical presentation Pat...
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Small airways

Small airways traditionally refer to distal airways that are 2-3 mm or less in calibre 3 with a wall thickness of less than 0.5 mm 5. These therefore include terminal bronchi (have cartilage) as well as bronchioles (no cartilage). They may or may not be directly visible on CT. Related pathology...
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Small airways disease

Small airways disease comprise of a group infectious as well as non-infectious conditions that affect the small airways (i.e. airways that are more peripheral to the main bronchi and proximal bronchioles (4th the 14th generation) - arbitrarily considered to be those with an internal diameter of ...
Article

Small cell lung cancer

Small cell lung cancer (SCLC), also known as oat cell lung cancer, is a subtype of bronchogenic carcinoma and considered separate from non-small-cell lung cancer (NSCLC) as it has a unique presentation, imaging appearances, treatment, and prognosis. Small cell lung cancers rapidly grow, are high...
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Small cell lung cancer (staging - superseded)

Previously, small cell lung cancer (SCLC) was not staged in the same manner as non-small cell lung cancer (NSCLC), but since 2013 both are staged using the IASLC (International Association for the Study of Lung Cancer) lung cancer staging system (currently in its 8th edition, published in 2016)....
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Small lung volume (differential diagnosis)

The following differentials can be considered when small lung volumes are seen: pulmonary fibrosis prior surgery, e.g. lobectomy, lung volume reduction surgery pleural disease skeletal deformities, e.g. kyphosis, scoliosis  systemic lupus erythematosus (SLE) neuromuscular disorders, e.g. p...
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Small pulmonary nodules (HRCT chest approach)

Small pulmonary lung nodules refer to an HRCT chest imaging descriptor for 5-10 mm lung nodules and are divided into three main categories based on their distribution pattern: centrilobular perilymphatic random Approach Distribution Firstly, determine whether the nodules are perilymphatic ...
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Smoking related lung disease

Smoking related lung diseases are the respiratory manifestations of disease that is related to smoking. Smoking affects the lungs in numerous ways, and can be classified under the following headings: smoking related interstitial lung diseases (SR-ILD) respiratory bronchiolitis respiratory br...
Article

Sniff test

The fluoroscopic sniff test, also known as diaphragm fluoroscopy, is a quick and easy real time fluoroscopic assessment of diaphragmatic motor function (excursion). It is used most often to confirm absence of muscular contraction of the diaphragm during inspiration in patients with phrenic nerve...
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Snowman sign (total anomalous pulmonary venous return)

Snowman sign refers to the configuration of the heart and the superior mediastinal borders resembling a snowman. This is seen in total anomalous pulmonary venous return (TAPVR) type I (supracardiac type). It is an abnormality of the fetal circulation wherein the entire pulmonary venous flow is ...
Article

Soft-tissue sarcoma

Soft-tissue sarcomas are a heterogeneous group of malignant tumours of mesenchymal origin (sarcoma) that originate from the soft tissues rather than bone. They are classified on the basis of tissue seen on histology. The commoner sarcomas in the adult and paediatric population are listed below. ...
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Solitary pulmonary nodule (an approach)

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...
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Solitary pulmonary nodules

Solitary pulmonary nodule (SPN) is defined as a relatively well defined round or oval pulmonary parenchymal lesion equal or smaller than 30 mm in diameter. It is surrounded by pulmonary parenchyma and/or visceral pleura and is not associated with lymphadenopathy, atelectasis, or pneumonia 9. Qu...
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Sonographic approach to dyspnoea (mnemonic)

This mnemonic will help with the sonographic approach to the critically ill patient with dyspnoea: CHEST Mnemonic C: collapsed lung (pneumothorax)  ​absent anterior lung sliding / anterior B lines lung point present 1 H: heart failure (acute pulmonary oedema) diffuse bilateral anterior B ...
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Spindle cell carcinoma of lung

Spindle cell carcinoma of the lung a very rare primary pulmonary malignancy. It is sometimes classified as a sarcomatoid carcinoma of the lung. Some authors also use the term synonymously with pleomorphic carcinomas of the lung, while the WHO 1999 classification system places the latter as a sep...
Article

Spinnaker sign (mediastinum)

The spinnaker sign (also known as the angel wing sign) is a sign of pneumomediastinum seen on neonatal chest radiographs. It refers to the thymus being outlined by air with each lobe displaced laterally and appearing like spinnaker sails. This is distinct from the sail sign appearance of the nor...
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Split pleura sign (empyema)

The split pleura sign is seen with pleural empyemas and is considered the most reliable CT sign helping to distinguish an empyema from a peripheral pulmonary abscess (see empyema vs pulmonary abscess) 1,2.  The sign results from fibrin coating both the parietal and visceral surfaces of the pleu...
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Spontaenous haemopneumothorax

Spontaneous haemopneumothorax is a subtype of a haemopneumothorax where there is accumulation of blood and air within the pleural space in the abscence of trauma or other definitive cause. Pathology The source of bleeding is uncertain but in many cases can result from shearing of the adhesions...
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Squamous cell carcinoma in situ of the lung

Squamous cell carcinoma in situ (CIS) of the lung is a considered a preinvasive type of non-small cell lung cancer.  In some situations, this histology can also be found around the bronchial stump margin after resection of bronchial cancer, when there is presence of CIS on histology in a bronch...
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Squamous cell carcinoma of the lung

Squamous cell carcinoma (SCC) is one of the non-small cell carcinomas of the lung, overtaken by adenocarcinoma of the lung as the most commonly encountered lung cancer.  Epidemiology Squamous cell carcinoma accounts for ~30-35% of all lung cancers and in most instances are due to heavy smoking...
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Squamous dysplasia of lung

Squamous dysplasia (SD) of lung is a type of preinvasive lung lesion and is considered a precursor to bronchogenic squamous cell carcinoma. It is sometimes considered a low end of the spectrum of carcinoma in situ (CIS) of lung 2.
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Stab wound: overview

Stab wounds are a form of penetrating trauma that may be self-inflicted or inflicted by another person either accidentally or intentionally. They may be caused from a variety of objects and may occur anywhere in the body. Terminology Although commonly caused by a knife as well, slash injuries ...
Article

Stag's antler sign (lungs)

The stag's antler sign refers to upper lobe pulmonary venous diversion (cephalisation) in pulmonary venous hypertension or pulmonary oedema as seen on frontal chest radiograph. The prominence of upper lobe pulmonary veins resemble a stag's antlers. It is the earliest sign of pulmonary venous hy...
Article

Standard uptake value

The standard uptake value (SUV) is a simple way of determining activity in PET imaging, most commonly used in fluorodeoxyglucose (FDG) imaging. It is also known as the dose uptake ratio (DUR). As the name suggests it is a mathematically derived ratio of tissue radioactivity concentration at a po...
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Stanford classification of aortic dissection

Along with the DeBakey classification, the Stanford classification is used to separate aortic dissections into those that need surgical repair, and those that usually require only medical management. The Stanford classification divides dissections by the most proximal involvement: type A: A aff...
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Sternal body

The sternal body or gladiolus is the middle and largest of the three parts of the sternum.  It is formed by the fusion of four sternebrae which finish ossifying after puberty. Gross anatomy The sternal body is the longest of the three parts of the sternum and is widest near its lower end. It i...
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Sternal foramen

Sternal foramen (or perforated sternum) is a developmental variant of the sternum and results from incomplete fusion of the sternal ossification centres. They are common occurring in approximately 5% of the population (range 4.3-6.7%). They are most commonly found in the inferior aspect of the s...
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Sternal fracture

Sternal fractures occur in ~5% of blunt chest trauma with the manubrium being the most commonly injured part. Clinical presentation Acute, severe sternal pain that is worse with respiration with localised tenderness. Pathology Mechanism of injury Fractures of the sternum can result from bot...
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Sternalis muscle

The sternalis muscle is an uncommon anatomic variant of the chest wall musculature and is of uncertain aetiology and function. Its importance lies in that it should not be mistaken for a pathological lesion.  Epidemiology Cadaveric studies have shown that the muscle is present in ~5% (range 1-...
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Sternum

The sternum completes the anterior chest wall as the ventral breastplate. Gross anatomy The sternum is composed of a manubrium, a body and the inferior xiphisternum or xiphoid process. These articulations are via hyaline cartilage with a fibrocartilaginous intervening disc:  the manubrium is ...
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Sternum (lateral view)

The lateral sternum view a radiographic investigation of the entire length of the sternum in profile. The view is used to query fractures or infection 1. Patient position patient is erect with the left or right side of the thorax adjacent to the image receptor patient's hands are behind their...
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Straight back syndrome

Straight back syndrome refers to loss of the normal thoracic kyphosis. Individuals with this condition can present with a cardiac murmur due to compression of the right ventricular outflow tract (RVOT) 2.   There is questionable association with mitral valve prolapse 1. 
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Subacute hypersensitivity pneumonitis

Subacute hypersensitivity pneumonitis develops when hypersensitivity pneumonitis continues beyond the acute phase (i.e. continues for weeks to months). While some publications suggest the disease to needs to prevail for between 1-4 months to fall into this category 6, it is important to realise ...
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Subacute invasive pulmonary aspergillosis

Subacute invasive pulmonary aspergillosis (previously known as chronic necrotising aspergillosis (CNA) or semi-invasive aspergillosis is subacute to chronic localised and indolent form of invasive aspergillosis. It is also sometimes grouped under the term chronic pulmonary aspergillosis. Epidem...
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Subcarinal air cyst

Subcarinal air cysts refer to small air cyst that can be detected on a CT scan. They are thought to represent small main bronchial diverticula although the former term is preferred 2. They may be associated with chronic airflow limitation. Clinical presenation Patients are asymptomatic and the...
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Subclavian artery

The subclavian arteries are asymmetric paired arteries that supply blood to the posterior cerebral circulation, cerebellum, posterior neck, upper limbs and the superior and anterior chest wall. Gross anatomy Origin Right and left subclavian arteries classically have different origins: right ...
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Subclavian vein

The subclavian vein (SCV) is the major venous channel that drains the upper limb. Gross anatomy Origin and course The subclavian vein starts at the crossing of the lateral border of the 1st rib. It then arches cephalad, posterior to the medial clavicle before curving caudally and receiving it...
Article

Subcostal muscle

The subcostal muscle has variable anatomy and forms part of the intercostal muscle group. It lies on the deep surface of the innermost intercostal muscle in the posterior chest, near the angles of the ribs, usually running over 2-3 intercostal spaces. It is most common in the upper (1-4) and low...
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Subcostal nerve

The subcostal nerve can also be considered as the twelfth intercostal nerve. Some authors describe it as the first branch of the lumbar plexus. Gross anatomy The anterior division of the twelfth thoracic nerve, called the subcostal nerve, is larger than the other intercostal nerves. It runs al...
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Subcutaneous emphysema

Subcutaneous or surgical emphysema, strictly speaking, refers to air in the subcutaneous tissues. But the term is generally used to describe any soft tissue emphysema of the body wall or limbs since the air often dissects into the deeper soft tissues and musculature along fascial planes. Clinic...
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Subpleural line

Subpleural line refers to a thin curvilinear opacity, 1-3 mm in thickness, lying less than 1 cm from and parallel to the pleural surface. It corresponds to: atelectasis of normal lung if seen in the dependent posteroinferior portion of lung of a patient in the supine position (disappears if pro...
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Subpleural pulmonary bullae

Subpleural pulmonary bullae are a location-specific descriptive term to describe pulmonary bullae occurring in subpleural locations. Many are considered to represent regions of paraseptal emphysema where the emphysematous spaces are greater than 1cm in diameter 1. They may or may not contain sep...
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Subpleural sparing

Subpleural sparing in thoracic radiology is a imaging descriptor usually used on cross sectional imaging (mainly CT) where the pathology that affects the lungs spares the extreme peripheral lung margin abutting the pleura - chest wall. It can be seen in a number of situations non specific inte...
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Subpulmonic effusion

Subpulmonic effusions are a pleural effusion that can be seen only on an erect projection. Rather than layering laterally and blunting the costophrenic angle, the pleural fluid lies almost exclusively between the lung base and the diaphragm. Radiographic features Plain radiograph The fluid ca...
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Superficial endobronchial carcinoma

A superficial endobronchial lung cancer may be defined as a bronchogenic tumour of any size with its invasive component limited to the bronchial wall. It may extend into the proximal bronchus and is often classified as T1 at TNM staging. It is one of the causes of more focal bronchial wall thick...
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Superior accessory fissure

The superior accessory fissure is present in around 5% of individuals examined with CT 4.  Gross anatomy The superior accessory fissure of the right lower lobe is located in the same plane and posterior to the right minor fissure. It separates the right lower lobe into superior and basal segme...
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Superior mediastinum

Superior mediastinum is an artificially divided wedge-shaped compartment of the mediastinum located between the thoracic plane inferiorly and the thoracic inlet superiorly. The inferior mediastinum, comprising of the anterior, middle and posterior parts, lies inferiorly. Gross anatomy Boundari...
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Superior pulmonary sulcus

The superior pulmonary sulcus (or just the superior sulcus) refers to an apical pleuro-pulmonary groove formed by the subclavian artery as it curves in front of the pleura runs upward and lateral immediately below the apex. It is a typical location for Pancoast tumours (also known as superior su...
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Superior thoracic aperture

The superior thoracic aperture, also known as the thoracic inlet or outlet, connects the root of the neck with the thorax.  Gross anatomy The superior thoracic aperture is kidney-shaped and lies in an oblique transverse plane, tilted anteroinferiorly to posterosuperiorly.  Boundaries posteri...
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Superior vena cava

The superior vena cava (SVC) is a large valveless venous channel formed by the union of the brachiocephalic veins. It receives blood from the upper half of the body (except the heart) and returns it to the right atrium. Gross anatomy The SVC begins behind the lower border of the first right co...
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Superior vena caval duplication

Superior vena caval (SVC) duplication is the most common form of a left-sided SVC, where the normal right-sided SVC remains. The right SVC, however, can be smaller in approximately two-thirds of such cases 3. Pathology Results from failure of the embryonic left anterior cardiac vein to regress...
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Superior vena cava obstruction

Superior vena cava (SVC) obstruction can occur from extrinsic compression, intrinsic stenosis or thrombosis. Malignancies are the main cause and are considered an oncologic emergency. Superior vena cava syndrome (SVCS) refers to the clinical syndrome with symptoms that results from this obstruct...
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Suprapleural membrane

The suprapleural membrane, also known as Sibson fascia, is a dense fascial layer that is attached to the inner border of the first rib and costal cartilage anteriorly, C7 transverse process posteriorly and to the mediastinal pleura medially. It is flat and lies in the oblique plane of the thora...
Article

Suprascapular artery

The suprascapular artery is 1 of the 4 branches of the thyrocervical trunk (off the first part of the subclavian artery). It traverses inferiorly and laterally in the lower anterior neck superficial to the anterior scalene muscle and phrenic nerve before crossing the third part of the subclavia...
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Supreme intercostal arteries

The supreme intercostal arteries, or superior intercostal arteries, are formed as a direct result of the embryological development of the intersegmental arteries. These arteries are paired structures of the upper thorax which normally form to provide blood flow to the first and second intercosta...
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Surgical emphysema (summary)

This is a basic article for medical students and other non-radiologists Surgical emphysema (or subcutaneous emphysema) occurs when air/gas is located in the subcutaneous tissues (the layer under the skin). This usually occurs in the chest, face or neck. Reference article This is a summary art...
Article

Swiss cheese sign (lungs)

The Swiss cheese sign has been used for the appearance on CT of fluid-containing pneumatocoeles, that typically occur following pulmonary lacerations 1. The pneumatocoeles appear as 'holes' in the lung parenchyma and hence the description with respect to Swiss-style cheeses (e.g. Emmental), whi...
Article

Swyer-James syndrome

Swyer-James syndrome (SJS), also known as Swyer-James-MacLeod syndrome and Bret syndrome, is a rare lung condition that manifests as unilateral hemithorax lucency as a result of postinfectious obliterative bronchiolitis.  Epidemiology The condition typically follows a viral respiratory infecti...
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Symptomatic pneumothorax (summary)

This is a basic article for medical students and other non-radiologists Pneumothoraces (singular: pneumothorax) are collections of gas within the pleural space. If the pneumothorax is under pressure, it is called a tension pneumothorax. Reference article This is a summary article; read more i...
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Synchronous primary lung carcinoma

Synchronous primary lung carcinoma (SPLC) is a term given to the occurrence of two or more primary lung carcinomas within different portions of the lung in the same time period. They are thought to the carry the same pathophysiological mechanism as metachronous lung carcinoma (i.e. two or more ...
Article

Syndrome of inappropriate antidiuretic hormone secretion

Syndrome of inappropriate antidiuretic hormone secretion (SIADH or SIAD) was described in patients with lung cancer who developed hyponatraemia associated with continued urinary sodium loss. The result is often dilutional hyponatremia in which the sodium remains normal but total body fluid incre...
Article

Systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multisystem involvement. It is also sometimes classified as a vasculitis.  Epidemiology There is an overall increased female predilection. In adults, women are affected 9-13 times more than males. In children, this ratio i...
Article

Systemic lupus erythematosus (thoracic manifestations)

Thoracic manifestations of systemic lupus erythematosus can be variable.  For a general discussion, and for links to other system specific manifestations, please refer to the article on systemic lupus erythematosus.  Pathology Pleuropulmonary manifestations pleuritis: considered one of the c...
Article

Takayasu arteritis

Takayasu arteritis (TA), also known as idiopathic medial aortopathy or pulseless disease, is a granulomatous large vessel vasculitis that predominantly affects the aorta and its major branches. It may also affect the pulmonary arteries. The exact cause is not well known but the pathology is thou...
Article

Takeuchi procedure

The Takeuchi procedure refers to a direct anastomosis of the anomalous left coronary artery from the pulmonary artery directly to the aorta was described in the 1970s and currently remains the procedure of choice. An intrapulmonary aortocoronary tunnel or baffle was performed by Takeuchi prior ...
Article

Talc induced lung disease

Talc induced lung disease comprises of a group of pathologies that can occur related to talc (Magnesium silicate) Four types of pulmonary disease secondary to talc exposure have been defined these include: talco-silicosis - associated with occupational exposure talco-asbestosis - associated w...
Article

Talcosis

Talcosis is a type of pneumoconiosis and can be prevalent in intravenous drug users. It is one of the four recognised types talc induced lung disease. Pathology Talc (magnesium silicate) is used in the preparation of tablets intended for oral use, where it acts as a 'filler' and lubricant. Whe...
Article

Talc pleurodesis

Talc pleurodesis is one of the chemical methods of pleurodesis which is a procedure performed to prevent recurrence of a pneumothorax or recurrent pleural effusion in benign or malignant conditions. It involves achieving an area of adhesion between the parietal and visceral layers of the pleura....
Article

Talc pulmonary embolism

Talc (magnesium trisilicate) pulmonary embolism is a rare cause of non thrombotic pulmonary embolism. It tends to be more prevalent in patients with narcotic abuse. Clinical presentation Most patients are asymptomatic although dyspnea and persistent cough occur with severe talc exposure. Clini...
Article

Tc-99m DTPA (aerosol)

Tc-99m DTPA (diethylenetriamine-pentaacetic acid) (aerosol) is one of the technetium agents and is used in VQ imaging. Characteristics photon energy: 140 KeV physical half life: 6 hours biological half life: 1 hour normal distribution: lungs pharmacokinetics: aerosol deposited in bronhoal...
Article

Tc-99m MAA

Tc-99m MAA (macroaggregated albumin) is one of the technetium radiopharmaceuticals used in lung perfusion imaging. Characteristics photon energy: 140 KeV physical half life: 6 hours biological half life: 2-3 hours normal distribution: lungs, liver, spleen, kidneys pharmacokinetics: >90% p...
Article

Technetium agents

Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. The radioactive technetium radiotracer can be chelated to a number of different compounds to create specific radiopharmaceuticals and optimise the functional imaging of various stru...
Article

Tension gastrothorax

Tension gastrothorax describes a rare life-threatening condition caused by mediastinal shift due to a distended stomach herniating into the thorax through a diaphragmatic defect.  Clinical presentation Presentation is generally with acute and severe respiratory failure, with clinical features ...
Article

Tension pneumothorax

Tension pneumothoraces occur when intrapleural air accumulates progressively in such a way as to exert positive pressure on mediastinal and intrathoracic structures. It is a life-threatening occurrence requiring both rapid recognition and prompt treatment to avoid a cardiorespiratory arrest. Fo...
Article

Tension pneumothorax (summary)

This is a basic article for medical students and other non-radiologists Tension pneumothoraces are pneumothoraces under pressure. If the pressure gets high enough, the pneumothorax can compress the heart and great vessels, and even cause cardiac arrest. Clinical presentation Presentation is u...
Article

Terminal bronchiole

The terminal bronchioles are a continuation of the bronchi and are the last divisions of the conducting airways.   Gross Anatomy Terminal bronchioles, are confusingly named, as they not the final branches but rather the distal bronchioles that do not bear alveoli.  The first 19 divisions from ...
Article

Thalassaemia

Thalassaemia is an autosomal recessive haemoglobinopathy that originated in the Mediterranean region. The genetic defect causes a reduction in the rate of globin chain synthesis which causes the formation of abnormal haemoglobin molecules. The resultant microcytic anaemia is the characteristic p...
Article

The Macklin effect: pulmonary interstitial emphysema and pneumomediastinum

The Macklin effect describes one of the pathophysiological processes of pneumomediastinum in blunt chest trauma. The Macklin effect accounts for ~40% of severe blunt traumatic pneumomediastinum. Exclusion of tracheobronchial and oesophageal causes of pneumomediastinum is mandatory to exclude con...

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