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.

568 results found
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Secondary involvement of the bone with lymphoma

Secondary involvement of the bone with lymphoma, also referred as secondary bone lymphoma, is much more common than primary bone lymphoma, occurring in ~15% of disseminated lymphomas. Terminology Secondary bone lymphoma is defined as lymphoma involving the bone with nodal disease occurring wit...
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Secondary involvement of the pleura with lymphoma

Secondary involvement of the pleura with lymphoma (secondary pleural lymphoma) is very common, occurring in ~20% of lymphomas. It may be a result of an extension of lymphoma into the visceral or parietal pleura or be a complicating pleural effusion and is a poor prognostic factor.  Epidemiology...
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Secondary organising pneumonia

Secondary organising pneumonia (SOP) refers to organising pneumonia that can be attributed to a specific cause, in contrast to cryptogenic organising pneumonia (COP). Pathology Aetiology SOP can be attributed to the following causes 1: Prior infection bacteria atypical pneumonias (e.g. Leg...
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Second branchial cleft cyst

Second branchial cleft cysts are a cystic dilatation of the remnant of the 2nd branchial apparatus, and along with 2nd branchial fistulae and sinuses accounts for 95% of all branchial cleft anomalies. Clinical presentation Although a congenital abnormality, they tend to present in early adulth...
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Selective internal radiation therapy

Selective internal radiation therapy (SIRT), also know as hepatic radioembolisation, is a relatively new and developing modality for treating non-resectable liver tumours. The procedure consists of a transcatheter injection of radioactive particles via the hepatic artery.  It is generally consi...
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Sezary syndrome

Sézary syndrome (SS) is a type of cutaneous T-cell lymphoma. It is sometimes considered an advanced and leukaemic form of cutaneous T-cell lymphoma (CTCL). Clinical presentation It is clinically characterised by an extensive erythematous rash covering most of the body as well as the presence o...
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Siewert-Stein classification of oesophageal adenocarcinoma

The Siewert-Stein classification of oesophageal adenocarcinoma classes these tumours according to their relationship to anatomical landmarks 1. It was initially proposed by Siewert et al in 1996, becoming widely used in predicting lymph node spread and directing optimal management. As of the 7th...
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Sinonasal adenocarcinoma

Sinonasal adenocarcinomas are primary tumours of the sinonasal region with glandular differentiation. They are grossly classified as salivary and non-salivary subtypes. However, generally in the literature and IARC/WHO classification, the term Sinonasal adenocarcinoma refers to non-salivary aden...
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Sinonasal lymphoma

Sinonasal lymphoma refers to the involvement of the nasal cavity and/or paranasal sinuses with lymphoma. It can be primary or secondary. Clinical presentation Presenting symptoms of sinonasal lymphoma are variable but are usually similar to those of benign inflammatory diseases. The clinical s...
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Sinonasal mucosal melanoma

Sinonasal mucosal melanoma (SNMM) is a very rare and unique subtype of malignant melanoma. Epidemiology SNMMs account for ~1% of malignant melanomas and <4% of head and neck cancers 1,2. They affect older patients (60-90 years old) 2. There is a higher incidence in Japan 5.  Clinical presenta...
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Skeletal muscle metastases

Skeletal muscle metastases are uncommon compared to other sites and are generally seen in the context of widespread metastatic disease.  Epidemiology Post-mortem rates of skeletal metastases vary between 0.03% and 17% 1.  Clinical presentation Most commonly asymptomatic 2,3.  Pathology Com...
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Skin cancer

Skin cancers refer to malignancies arising from the skin. This is a general discussion of skin cancers, for discussions of specific skin cancers please refer to individual articles. Epidemiology Overall, skin cancers are the most common human malignancy 1. Pathology Primary skin malignancy ...
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Skull metastases

Metastases to the skull are very common in patients with disseminated skeletal metastatic disease, although they are often asymptomatic. For a more detailed general discussion please refer to the article on skeletal metastatic disease. Epidemiology Skull metastases are seen in ~20% (range 15-2...
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Small bowel carcinoid tumour

Small bowel carcinoid tumours are the most common gastrointestinal carcinoid tumours and most frequently involves the terminal ileum. Epidemiology Small bowel carcinoid tumours account for ~40% of gastrointestinal carcinoid tumours 1.  Clinical presentation Small bowel carcinoids are slow gr...
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Small bowel lymphoma

Small bowel lymphoma is the most common small bowel malignancy, accounting accounts for ~25% of all primary small bowel malignancies and ~40% of all primary gastrointestinal lymphomas. Epidemiology Small bowel lymphoma is most commonly secondary extranodal involvement in widespread systemic ly...
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Small cell carcinoma of the bladder

Small cell carcinomas of the bladder are rare bladder cancers with a poor prognosis. Its appearance overlaps other bladder cancers, in particular, urothelial/transitional cell carcinoma. Epidemiology A very rare tumor, it has been estimated at <0.0001% of bladder cancers. It is thought to have...
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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...
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Soft tissue calcification (mnemonic)

Mnemonics to remember the causes of soft tissue calcification include: My GHOSTS 1 TIC MTV 2 Mnemonic  My GHOSTS My: myositis ossificans G: gout H: hyperparathyroidism O: ochronosis S: scleroderma/connective tissue disease T: tumoral calcinosis S: sarcoma (synovial cell) TIC MTV T: ...
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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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Solid and enhancing pituitary region mass

Solid lesions with enhancement is by far the most commonly encountered appearance of pituitary region masses. Differential diagnosis macroadenoma by far the most common entity typically enhances less vividly than other entities elevates the dura of the diaphragma sella (as the origin is wit...
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Solid periosteal reaction

Solid periosteal pattern is thought to evolve from single layer and multilayered periosteal reactions, forming a solid layer of new bone adjacent to the cortex. It can be seen in: osteoid osteoma osteomyelitis osteosarcoma chondrosarcoma fibrous dysplasia non-ossifying fibroma osteoblast...
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Solitary bone plasmacytoma

Solitary bone plasmacytomas is an uncommon plasma cell tumour which is localised to bone. They may involve any bone, but they have a predisposition for the red marrow-containing axial skeleton: spinal disease is observed in ~50% (range 34-72%) of cases the thoracic vertebrae are most commonly ...
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Solitary pulmonary nodule (an approach)

A solitary pulmonary nodule, according to the Nomenclature Committee of the Fleischner Society, is 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 r...
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Solitary sclerotic bone lesion

The differential diagnosis of a solitary sclerotic bone lesion is heavily influenced by the age of the patient, and includes: sclerotic metastasis solitary either because no others are present or no others have been imaged enostosis (bone island) osteosarcoma calcifying enchondroma osteobl...
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Sonographic features of malignant lymph nodes

Lymphadenopathy is quite common, and it can be very difficult to differentiate malignant lymphadenopathy from reactive nodal enlargement. Several gray scale and colour Doppler features favour malignancy in a lymph node. Gray scale parameters that favour malignancy size: larger-more likely mal...
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SpaceOAR

SpaceOAR is a technique in which a physical space is created between the prostate gland and rectum for electron beam radiotherapy targeted to the prostate gland in cases of prostate cancer.  OAR stands for "organ at risk", and in cases of prostate cancer radiotherapy treatment the rectum is the...
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Spermatic cord leiomyosarcoma

Spermatic cord leiomyosarcomas are uncommon malignant paratesticular masses. Epidemiology Accounts for ~10% of spermatic cord sarcomas. The average of a patient at presentation is 58 years old (although has been seen as young as 15 years old). Clinical features Patients may have left inguina...
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Spermatic cord liposarcoma

Spermatic cord liposarcomas are the most common malignant tumour of the spermatic cord. Most present as painless, slow-growing masses and can be mistaken for inguinal hernias. They are usually well-differentiated and spread by local extension.  Epidemiology In a large population-based registry...
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Spinal astrocytoma

Spinal astrocytomas are the second most common spinal cord tumour overall, representing 40% of intramedullary tumours 3. They account for 60% of paediatric intramedullary tumours, making them the most common spinal cord tumour in children 6. This article specifically relates to spinal astrocyto...
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Spinal instability neoplastic score (SINS)

The spinal instability neoplastic score (SINS) helps to assess tumour related instability of the vertebral column. It has been shown to useful in guiding the mobilisation or operative management of patients with neoplastic spinal disease. Studies have reported good inter-observer agreement amon...
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Spinal metastases

Spinal metastases is a vague term which can be variably taken to refer to metastatic disease to any of the following: vertebral metastases (94%) may have epidural extension intradural extramedullary metastases (5%) intramedually metastases (1%) Each of these are discussed separately. Below ...
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Spinal paraganglioma

Spinal paragangliomas are tumours of neuroendocrine origin that rarely involve the central nervous system, usually the filum terminale and cauda equina). They are indolent and considered WHO grade I lesions 5.  Paragangliomas overall are most commonly located within the adrenal gland (pheochrom...
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Splenic lymphoma

Splenic lymphoma, also termed as lymphomatous involvement of the spleen, represents the most common malignancy to involve the spleen. They are commonly secondary, rarely being primary (referred as primary splenic lymphoma).   This article focuses on the location-specific primary and secondary l...
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Splenic metastases

Splenic metastases are relatively rare on imaging, although they are more commonly found on autopsy. Typically they are part of a widespread metastatic disease. Epidemiology The rate of splenic metastases varies between 1-10% of autopsy studies, depending on whether microscopic or macroscopic ...
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Splenomegaly

Splenomegaly is a term which refers to enlargement of the spleen. The normal adult splenic length upper limit is usually around 12-15 cm. It can also be helpful to know how to calculate splenic index, volume and mass by CT and MR techniques. Massive splenomegaly is a term used when the spleen we...
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Squamous cell carcinoma (head and neck)

Squamous cell carcinomas (SCC) of the head and neck are common, being the sixth most common cancer. They can have a cutaneous or mucosal origin. As such there is a wide array of clinical and radiographic manifestations, and are separated into: squamous cell carcinoma of the skin of the head and...
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Squamous cell carcinoma of the larynx

Squamous cell carcinoma of the larynx is the most common primary malignant tumour that affects the laryngeal framework. Typically it is categorised by the laryngeal subsite affected, which affects presentation, treatment and prognosis.  Epidemiology Males are more affected than females, and us...
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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 cell carcinoma of the oral cavity (staging)

Staging of oral cavity squamous cell carcinoma uses the TNM staging system. Primary tumour staging (T) Tx - tumour cannot be assessed T0 - no evidence of primary tumour Tis - carcinoma in situ T1 - tumour 2 cm or less in greatest dimension T2 - tumour greater than 2 cm and less than 4 cm i...
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Squamous cell carcinoma of the penis (staging)

Squamous cell carcinoma of the penis arises most commonly at the distal end of the penile urethra with local invasion of the glans. In addition to TNM classification, the following staging is used: Staging stage I: confined to the glans or foreskin stage II: invasion of penile shaft stage I...
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Stereotactic ablative radiotherapy

Stereotactic ablative radiotherapy (SABR) is a technique used to treat certain cancers as an alternative to surgical resection. It can be used to treat early lung cancer and hepatocellular carcinoma.
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Stipple sign (transitional cell carcinoma)

The stipple sign refers to the pointillistic end-on appearance on intravenous pyelography or retrograde pyelography of contrast material tracking into the interstices of a papillary lesion. Because the majority of transitional cell carcinomas (TCC) have a papillary configuration, the presence of...
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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 obstruc...
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Superscan

Superscan is intense symmetric activity in the bones with diminished renal and soft tissue activity on a Tc99m diphosphonate bone scan. This appearance can result from a range of aetiological factors: diffuse metastatic disease prostatic carcinoma breast cancer transitional cell carcinoma (...
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Sweet syndrome

Sweet syndrome (acute febrile neutrophilic dermatosis) is characterised by a constellation of clinical symptoms, physical features, and pathologic findings which include: fever neutrophilia tender erythematous skin lesions (papules, nodules, and plaques) a diffuse infiltrate consisting predo...
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Synchronous breast cancer

Synchronous breast cancers are two (or more) primary breast cancers that occur in either breast at the same time.  Epidemiology Up to 10% of all breast cancers may be synchronous (particularly found with the use of breast MRI). The occurrence of bilaterality is greatest with invasive lobular c...
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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...
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Synonyms

Synonyms, located below references when in edit mode, are used in a number of scenarios.  To view a YouTube screencast tutorial please click here.  What is a synonym? A synonym is essentially a 'redirect' to an article. This enables links created to article A to pass to article B, provided ar...
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Synovial sarcoma

Synovial sarcomas are relatively common intermediate-to-high grade malignant soft tissue tumours, often with an initial indolent course, affecting young patients, and most commonly involving the soft tissue surrounding the knees. Epidemiology Synovial sarcomas typically present in adolescents ...
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Tamoxifen-associated endometrial changes

Tamoxifen has pro-oestrogenic effects on the endometrium and thus is associated with an increased prevalence of: endometrial polyps: occurs in ~8-36% of women in treated 8 endometrial hyperplasia: occurs in ~1-20% of women treated ref cystic endometrial atrophy endometrial carcinoma Epidemi...
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T-cell prolymphocytic leukaemia

T-cell prolymphocytic leukaemia (T-PLL) is a rare and unusual haematological malignancy. Epidemiology It represents around 2% of all mature lymphocytic leukaemias in adults over the age of 30 1. It usually affects older adults with an average age at presentation being around 65 years. There ma...
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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...
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Technique of masking

Masking is very important when viewing mammograms, especially with high-density breasts. It helps the adaptation of the eye to the luminance of the mammograms on the viewbox.                     The technique of masking allows the comparative study of small areas of both breasts and is a featur...
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Terminal ileitis (differential)

The differential diagnosis for a terminal ileitis is quite extensive, and includes: inflammatory bowel disease Crohn disease (most common) backwash ileitis due to ulcerative colitis infectious colitis Yersinia spp.  Yersinia enterocolitica Yersinia pseudotuberculosis Salmonella spp. Clo...
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Testicular cancer

Testicular cancers are the most common neoplasm in men between the ages of 20 and 34 years. Epidemiology Testicular cancer is uncommon, accounting for less than 1% of all internal organ malignancies 2. The demographics of affected individuals depends on the age of the histology of the tumour....
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Testicular lymphoma

Testicular lymphoma is an uncommon testicular malignancy. Lymphoma can involve the testes in three ways: primary site of extranodal disease (primary testicular lymphoma) secondary involvement of systemic disease primary manifestation of subclinical systemic disease This article is concerned ...
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Testicular seminoma

Testicular seminomas are the most common testicular tumours and account for ~45% of all primary testicular tumours. This article concerns itself only with testicular seminomas, however, seminomas can arise outside of the testicle most often within the anterior mediastinum, e.g. anterior mediasti...
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Testicular teratoma

Testicular teratoma, unlike ovarian teratoma, is often aggressive in its biological behaviour, and often exists as part of testicular mixed germ cell tumours.   Epidemiology Pure testicular teratomas account for only 4-9% of all testicular tumours. A similar number are seen in the context of t...
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Thoracic lymph node stations

Thoracic lymph nodes are divided into 14 stations as defined by the International Association for the Study of Lung Cancer (IASLC) 1, principally in the context of oncologic staging. For the purpose of prognostication, the stations may be grouped into 7 zones.  The IASLC definitions leave some a...
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Thymic carcinoma

Thymic carcinoma is part of the malignant end of thymic epithelial tumours. Epidemiology Patients are typically 50 to 70 years of age at presentation 9. Pathology The incidence of paraneoplastic syndromes is thought to be low. At least 10 different histologic variants have been described 4. ...
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Thymic hyperplasia

Thymic hyperplasia is a disorder whereby there is hyperplasia of the thymus gland.  Pathology Thymus hyperplasia can be subdivided into two forms:  true thymic hyperplasia lymphoid hyperplasia Both true thymic hyperplasia and lymphoid hyperplasia manifest as diffuse symmetric enlargement of...
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Thyroid-associated orbitopathy

Thyroid-associated orbitopathy is the most common cause of proptosis in adults and is most frequently associated with Graves disease. On imaging, it is characterised by bilateral and symmetrical enlargement of the extraocular muscle bellies. The typical distribution is inferior rectus > medial r...
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Thyroid lymphoma

Thyroid lymphoma is rare, accounting for a minority of both thyroid malignancies and lymphoma in general.  The thyroid may be affected primarily or secondary to lymphoma elsewhere. This article is concerned with primary thyroid lymphoma.  Epidemiology Thyroid lymphoma accounts for <5% of thyr...
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Thyroid malignancies

Thyroid malignancies are most commonly primary thyroid cancers but can rarely be metastatic deposits. Pathology Classification Thyroid malignancies can be categorised into the following key subtypes: primary thyroid cancers ​papillary thyroid carcinoma: 60-80% of carcinomas follicular thyr...
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Thyroid scan (I-123)

Thyroid scan (thyroid scintigraphy) is a nuclear medicine examination used to evaluate thyroid tissue.  Clinical indications functional status of a thyroid nodule thyrotoxicosis: differential diagnosis thyroid cancer whole body scan for distant metastases estimation of local residual thyro...
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TNM staging system

The TNM system has been widely adopted in many areas as a replacement for idiosyncratic disease specific systems. The precise details depend on the primary tumour site and/or histology but in general: TNM T: Tumour Tx: primary tumour cannot be assessed T0: no evidence of primary tumour Tis:...
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Tolosa-Hunt syndrome

Tolosa-Hunt syndrome (THS) is an idiopathic inflammatory condition that involves the cavernous sinus and orbital apex, and is essentially a clinical diagnosis of exclusion. Clinical presentation Clinically it refers to the presence of a painful ophthalmoplegia secondary to surrounding cavernou...
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TP53 (gene)

The TP53 gene, located on chromosome 17, is a tumour suppressor gene, responsible for the production of the p53 protein, a transcription regulatory protein which works in concert with a number of other proteins, together forming the p53 pathway 1,2. Inherited mutations in this gene result in th...
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Tracheal masses

The differential for tracheal masses can be rather wide. For a single mass consider: metastasis  direct invasion from adjacent organ (lung, thyroid, oesophagus and larynx) distant metastasis (e.g. melanoma, breast, renal and colon cancer)  primary neoplasms: squamous cell carcinoma: common...
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Trachelectomy

Trachelectomy (sometimes known as a cervicectomy) refers to the removal of the uterine cervix.  It is sometimes performed as a uterine-sparing surgery for certain cases with cervical malignancy 2-3. When it is performed with the curative intent it is often termed a radical trachelectomy and is ...
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Tram-track sign (orbit)

Tram-track sign refers to the parallel thickening and enhancement around the optic nerve, and is most frequently seen in the setting of optic nerve meningioma. It may however also be seen in 1: orbital pseudotumour perioptic neuritis orbital sarcoidosis oribtal leukemia orbital lymphoma or...
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Transcoelomic spread

Transcoelomic spread describes the spread of a malignancy into body cavities that occurs via penetrating the surface of the peritoneal, pleural, pericardial, or subarachnoid spaces. For example, ovarian tumours can spread transperitoneally to the surface of the liver.
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Transitional cell carcinoma of the bladder (staging)

Transitional cell carcinoma of the bladder staging uses the TNM system which has replaced the previously widely used Jewett-Scott-Marshall tumour staging system. It is very similar to the staging of TCC of the renal pelvis and staging of TCC of the ureter. TNM staging T Ta: non-invasive papil...
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Transitional cell carcinoma (staging)

Staging of transitional cell carcinomas of the urinary tract vary according to the location of the tumour, and are staged using the TNM staging system.  transitional cell carcinoma of the renal pelvis transitional cell carcinoma of the ureter transitional cell carcinoma of the bladder  
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Transverse rectus abdominis musculocutaneous flap

Transplantation of a transverse rectus abdominis myocutaneous (TRAM) flap is a commonly used surgical procedure for breast reconstruction following mastectomy. An autologous myocutaneous flap consisting of abdominal skin, subcutaneous fat, the rectus abdominis muscle, and adjoining vasculature ...
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Trousseau syndrome

Trousseau syndrome (not to be confused with Trousseau sign) represents the association between migratory thrombophlebitis and malignancy; hence one of its other names: cancer-associated thromboembolism. History and etymology  Armand Trousseau (1801-1867), was a French physician who was the fir...
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Tuberculosis (intracranial manifestations)

Tuberculosis of the central nervous system can result from either haematogenous spread from distant systemic infection (e.g. pulmonary tuberculosis) or direct extension from local infection (e.g. tuberculous otomastoiditis). Intracranial manifestations of tuberculosis are protean and can affect...
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Tuberculous cervical lymphadenitis

Tuberculous cervical lymphadenitis, also known as scrofula and King's evil, continues to be seen in endemic areas and in the industrialised world particularly among the immunocompromised. Epidemiology Tuberculous cervical lymphadenitis is the most common manifestation of extrapulmonary tubercu...
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Tumour markers

Tumour markers are a group of molecules in serum that are elevated in various malignancies and are often used to monitor treatment response as well as alert for potential progressive disease when in remission. Commonly used markers include: AFP (alpha fetoprotein) beta-hCG CA 19-9 CA 27-29 ...
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Tumours of the male urethra

Tumours of the male urethra are uncommon. They can be categorised both on the grounds of histology and location. Histology squamous cell carcinoma of the urethra: 80% urothelial/transitional cell carcinoma of the urethra: 15% (predominantly posterior urethra) adenocarcinoma of the urethra: 5...
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Tumour thrombus

Tumour thrombus is defined as tumour extending into a vessel, typically a vein. It occurs in a wide variety of malignancies. It is vital to distinguish tumour thrombus from "bland" thrombus (free of neoplastic cells) in the setting of neoplasia, as this often impacts staging and treatment approa...
Article

Typhlitis

Typhlitis, also called caecitis or neutropaenic colitis, is a necrotising inflammatory condition which typically involves the caecum and, sometimes, can extend into the ascending colon or terminal ileum. Epidemiology Typhlitis was first described in children with leukaemia and severe neutropae...
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Ultrasound appearances of liver metastases

Ultrasound appearance of liver metastases can have bewildering variation, and the presence of hepatic steatosis can affect the sonographic appearance of liver lesions. Radiographic features Ultrasound Patterns do exist between ultrasound appearance of the liver metastases and the likely prima...
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Ultrasound "U" classification of thyroid nodules

The ultrasound "U" classification of thyroid nodules has been developed by the British Thyroid Association (BTA) as part of their 2014 guidelines on the management of thyroid cancer 1. It allows for stratifying thyroid nodules as benign, suspicious or malignant based on ultrasound appearances t...
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Undifferentiated embryonal sarcoma of the liver

Undifferentiated embryonal sarcomas of the liver are rare, aggressive, and malignant liver tumours encountered in the paediatric population.  Epidemiology Approximately 90% of cases occur in patients under 15 years of age, most commonly between 6 and 10 years of age, but some cases have been r...
Article

Unilateral axillary lymphadenopathy (differential)

Unilateral axillary lymphadenopathy while being more concerning than bilateral axillary lymphadenopathy can still arise from a various benign as well as malignant causes. Benign mastitis other regional infective causes tuberculosis ipsilateral arm infection, e.g. cellulitis silicone induce...
Article

Unilateral testicular lesions

The differential diagnosis for unilateral testicular lesions is wide-ranging.  Neoplastic Common seminoma (40-50% of testicular malignancies) non-seminomatous germ cell tumours: testicular teratoma testicular epidermoid (teratoma with ectodermal elements only) testicular choriocarcinoma ...
Article

Urethral diverticulum

Urethral diverticula, or urethroceles, are focal outpouchings of the urethra. They should not be confused with a ureterocele of the distal ureter. Epidemiology Urethral diverticula occur far more frequently in women than in men and are estimated to occur in 1-6% of women, especially those with...
Article

Vertebral metastases

Vertebral metastases represent the secondary involvement of the vertebral spine by haematogenously-disseminated metastatic cells. They must be included in any differential diagnosis of a bone lesion in a patient older than 40 years. This article will focus only on the metastasis involving the b...
Article

Vertebra plana

Vertebra plana (a.k.a. pancake / silver dollar / coin-on-edge vertebra) is the term given when a vertebral body has lost almost its entire height anteriorly and posteriorly, representing a very advanced compression fracture. Plural is vertebrae planae. It can occur in a variety of settings, incl...
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VIPoma

VIPomas are a very rare type of pancreatic endocrine tumour that secrete, and get their name from, vasoactive intestinal peptide (VIP). The clinical syndrome resulting from these tumours is commonly known as WDHA syndrome, as an acronym of the cardinal symptoms of watery diarrhoea, hypokalaemia,...
Article

Visceral pleural invasion

Visceral pleural invasion is a feature that can be seen in lung cancers. It is defined as tumour extension beyond the elastic layer of the visceral pleura. It is considered an aggressive sign and one of the most important adverse prognostic factors in non-small cell lung cancers 1. Pathology G...
Article

Volcano sign (meningioma)

Volcano sign refers to the appearance of classical meningioma that resembels the appearance of volcano (viewed in cross-section MRI, parallel to dural attachment) in which there is triangular hyperostosis at the base of the meningioma (mountain) with the tumour being the cloud around it. The int...

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