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.

1,348 results found
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Benign lymphoepithelial lesions

Benign lymphoepithelial lesions (BLL or BLEL), also misleadingly known as AIDS-related parotid cysts (ARPC), are mixed solid and cystic lesions that enlarge the parotid glands, and are usually associated with cervical lymph node enlargement, and nasopharyngeal lymphofollicular hyperplasia. Term...
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Benign metastasising tumours

There are a number of benign metastasising tumours: benign metastasising meningioma 1,2 benign metastasising leiomyoma 3 primary adenoma of thyroid 4 giant cell tumour of bone 5
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Benign minor salivary gland pathology

Benign minor salivary gland pathology is a broad term that encompasses a number of relatively uncommon pathologies that affect the minor salivary glands of the head and neck: salivary retention cysts benign neoplasms pleomorphic adenoma
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Benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of vertigo. It occurs secondary to change in posture and typically is associated with nystagmus. The aetiology is thought to be due to changes of position of the otoliths in the inner ear, most commonly into the posteri...
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Bezold abscess

A Bezold abscess is a complication of acute otomastoiditis where the infection erodes through the cortex medial to the attachment of sternocleidomastoid, at the attachment site of the posterior belly of the digastric muscle, and extends into the infratemporal fossa. Due to it being deep to the i...
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Biffl scale for blunt cerebrovascular injury

The Biffl scale or grade illustrates the spectrum of blunt cerebrovascular injury (BCVI) seen on angiography (both CTA and DSA). Some authors refer to the grading scale as the Denver scale, which is not to be confused with the Denver criteria, a series of clinical indications and risk factors fo...
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Bilateral thinning of the parietal bones

Bilateral thinning of the parietal bones, also known as biparietal osteodystrophy, is an uncommon, slowly progressive acquired disease of middle-aged people with slight female predilection. It is typically an incidental finding.  Pathology The aetiology is unknown but is thought to be an age-r...
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Bill bar

Bill bar is a landmark that divides the superior compartment of the internal acoustic meatus into an anterior and posterior compartment. Anterior to Bill's bar, in the anterior superior quadrant, are the facial nerve (CN VII) and nervus intermedius, and posterior to it in the posterior superior ...
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Bimastoid line

The bimastoid line has been described and used to evaluate basilar invagination on frontal skull plain film and coronal reconstructed CT image. The bimastoid line is drawn between the inferior tips of the of mastoid processes bilaterally. The tip of the odontoid process of C2 normally projects ...
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Binocular distance

The binocular distance (BOD) is a measurement between the two lateral (outer) canthi of each eye. It is sometimes used as a accessory fetal biometric parameter where it is often documented on both 2nd trimester anatomy scans on axial brain scans. The largest diameter of the orbit should be used ...
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Biphenotypic sinonasal sarcoma

Biphenotypic sinonasal sarcoma, initially named low-grade sinonasal sarcoma with neural and myogenic features,  is a rare and only recently described low-grade sarcoma of the nasal and paranasal sinuses. The tumour exhibits both neural and myogenic differentiation and thus can be problematic to ...
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Black eyebrow sign

Black eyebrow sign is the description given on plain facial radiographs to intra-orbital air 1. Air rises into the most superior aspect of the orbit, almost always in the context of a facial fracture, in a linear fashion, giving the appearance of an eyebrow. The fracture is usually an orbital b...
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Black turbinate sign (nasal cavity)

The black turbinate sign refers to an area of non-enhancing mucosa on MRI in a patient with angioinvasive fungal sinus infection / rhinocerebral mucormycosis. Mucormycosis is caused by fungi that include Mucor, Rhizopus, and Absidia species.  It is seen in diabetic and immunocompromised patient...
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Blunt traumatic neck injury

Blunt traumatic neck injury is uncommon because it is usually protected by the head, shoulders, and chest. This term is generally used to refer to injuries of the neck besides to cervical spine injuries, which are common.  Pathology Blunt injury to the neck is most commonly from motor vehicle ...
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Body of sphenoid

The body of the sphenoid bone is the midline cubical portion of the sphenoid bone, hollowed by the sphenoid air sinuses.  Gross anatomy The body has superior, inferior, anterior, posterior, and lateral surfaces. The superior surface features: ethmoidal spine: prominent spine that articulates...
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Bogorad syndrome

Bogorad syndrome also known as the syndrome of crocodile tears, is characterized by residual facial paralysis with profuse lacrimation during eating. It is caused by a misdirection of the regenerating autonomic fibers to the lacrimal gland instead of to the salivary gland. Etymology Named afte...
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Bolger classification of maxillary sinus hypoplasia

The Bolger classification of maxillary sinus hypoplasia proposed by Bolger et al. in 1990 1 takes into account associated anomalies of the uncinate process, which are of utmost importance for planning functional endoscopic sinus surgery (FESS). Maxillary sinus hypoplasia in itself is asymptomat...
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Bony orbit

The bony orbit refers to the bones that constitute the margins of the orbits, that is the roof, medial and lateral walls and floor. The orbital margin or rim refers to the anterior circular margin of the orbit. The orbital apex refers to the posterior confluence of the orbit, where the optic can...
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Boogard's angle

Boogard's angle is measured by drawing a line from basion to opisthion and another line along the plane of the clivus to the basion intersecting the first line - the angle between these two lines is measured . The normal angle is 126° +/- 6°. If the angle measures more than 136° it is indicativ...
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Bouthillier classification of internal carotid artery segments

Bouthillier et al. described (in 1996) 1 a seven segment internal carotid artery (ICA) classification system. It remains the most widely used system for describing ICA segments at the time of writing (mid-2016). There are a few other classifications systems including those proposed by Fisher (1...
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Brachycephaly

Brachycephaly refers to a calvarial shape where the bi-parietal diameter to fronto-occipital diameter approaches the 95th percentile. It can result from a  craniosynostosis involving the coronal and lambdoid sutures. Pathology Associations Brachycephaly can be associated with numerous syndrom...
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Branches of maxillary artery (mnemonic)

A mnemonic for remembering the branches of the maxillary artery is: DAM I AM Piss Drunk But Stupid Drunk I Prefer, Must Phone Alcoholics Anonymous Mnemonic D: deep auricular artery A: anterior tympanic artery M: middle meningeal artery I: inferior alveolar artery A: accessory meningeal ar...
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Branches of the external carotid artery (mnemonic)

Mnemonics for the branches of the external carotid artery abound. A few colourful examples include:  Some American Ladies Found Our Pyramids Most Satisfactory Some Anatomists Like Freaking Out Poor Medical Students She Always Likes Friends Over Papa, Sister, and Mama There are many many many...
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Branches of the thoracoacromial artery (mnemonic)

Useful mnemonics to remember the four branches of the thoracoacromial artery are: ABCD CAlifornia Police Department Cadavers Are Dead People PACkeD Mnemonics ABCD A: acromial B: breast (pectoral) C: clavicular D: deltoid CAlifornia Police Department C: clavicular A: acromial  P: pe...
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Branchial cleft anomalies

Branchial cleft anomalies comprise of a spectrum of congenital defects that occur in the head and neck. Pathology The anomalies result from branchial apparatus (six arches; five clefts), which are the embryologic precursors of the ear and the muscles, blood vessels, bones, cartilage, and mucos...
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Branchio-oto-renal dysplasia

Branchio-oto-renal (BOR) dysplasia is a rare syndromic disorder characterised by: otic malformations can involve the outer, middle, and inner ear associated with conductive, sensorineural, or mixed hearing impairment preauricular pits branchial fistulae and branchial cleft cysts renal malfo...
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Bregma

The bregma is the midline bony landmark where the coronal and sagittal sutures meet, between the frontal and two parietal bones. It is the anterior fontanelle in the neonate and closes in the second 2 (typically around 18 months after birth). It is one of the skull landmarks, craniometric poin...
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Brown syndrome (orbit)

The Brown syndrome refers to an inability of a patient to perform an upward gaze while the eye is adducted due to an abnormality of the superior oblique tendon sheath complex. History and etymology It was first described by Allan Brown in 1950 1. See also Brown-Sequard syndrome
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Buccal nerve

The buccal nerve is the only purely sensory branch of the anterior division of the mandibular division of the trigeminal nerve. It is not to be confused with the buccal branch of the facial nerve. Gross anatomy The buccal nerve divides off the anterior division and passes with the paired nerve...
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Buccal space

The buccal space (or buccinator space) is one of the seven suprahyoid deep compartments of the head and neck. Gross anatomy  The buccal spaces are paired fat contained spaces on each side of the face forming cheeks. Each space is enveloped by the superficial (investing) layer of the deep cervi...
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Buccinator artery

The buccinator artery is a small branch from the second part of the maxillary artery. It runs obliquely forward, between the medial pterygoid and the insertion of the temporalis, to the outer surface of the buccinator, to which it is distributed, anastomosing with branches of the facial artery a...
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Bulla lamella

The bulla lamella is a structure that, when intact, forms the posterior boundary of the frontal recess. When pneumatised, it forms the ethmoid bulla. Gross anatomy It is frequently incomplete and often does not reach the roof of the ethmoid at the skull base. Under these circumstances, the fro...
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Buphthalmos

Buphthalmos is a descriptive term which simply means an enlarged eyeball or ocular globe due to increased intraocular pressure (glaucoma), without deformation or and intrinsic mass lesion. Epidemiology It typically manifests in infants and young children. Pathology It usually indicates the p...
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Calcification of the external ear (differential)

Calcification of the external ear (auricular cartilage) may arise from a number of causes, including: hyperparathyroidism gout and pseudogout relapsing polychondritis frostbite trauma ochronosis sarcoidosis diabetes mellitus adrenal insufficiency
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Calcification of the globe (differential)

Calcification of the globe has many causes, varying from the benign to malignant. When calcification is seen of the posterior half of the globe, it could relate to any of the layers (scleral, choroidal or retinal), as it is not possible to separate them out on CT. Retinal drusen: 1% population...
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Calcific tendinitis of the longus colli muscle

Calcific tendinitis of the longus colli muscles is an inflammatory/granulomatous response to the deposition of calcium hydroxyapatite crystals in the tendons of the longus colli muscle. Epidemiology This condition typically occurs in adults in middle age (20-50 years of age) with a slight pred...
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Calcifying epithelial odontogenic tumour

Calcifying epithelial odontogenic tumour, also known as a Pindborg tumour, is typically located in the premolar and molar region of the mandible, although up to a third are found in the maxilla. Epidemiology Usually they are seen in the 4th to 6th decades. They are rare tumours. Pathology As...
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Calcifying metastases (mnemonic)

A simple mnemonic to recall a list of commonly calcifying metastases is: BOTOM Mnemonic B: breast cancer O: osteosarcoma T: papillary thyroid cancer O: ovarian cancer (especially mucinous) M: mucinous adenocarcinoma (especially colorectal carcinoma)
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Canadian C-spine rules

Canadian C-spine rules are a set of guidelines that help a clinician decide if cervical spine imaging is not appropriate for a trauma patient in the emergency department. The patient must be alert and stable. There are three rules: is there any high-risk factor present that requires cervical s...
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Capillary haemangioma of the orbit

Capillary haemangiomas of the orbit, also known as strawberry haemangiomas, on account of its colouring, or orbital infantile haemangiomas, are the most common orbital tumours of infancy, and unlike orbital cavernous haemangiomas, they are neoplasms rather than vascular malformations. Clinical ...
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Capps triad

The Capps triad refers to the constellation of clinical and imaging findings in patients with spontaneous retropharyngeal haematomas, and consists of: tracheal and oesophageal compression anterior displacement of the trachea subcutaneous bruising over the neck and anterior chest History and ...
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Carcinoembryonic antigen

Serum carcinoembryonic antigen (CEA) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumour markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue. Normal range of CEA is...
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Carcinogens

Carcinogens are substances known to cause cancer. They include: Brain vinyl chloride Nasopharynx / nasal passage nickel wood dust chromium Thyroid ionising radiation (not technically a substance) Skin arsenic coal tars polyaromatic hydrocarbons (PAH) Lungs arsenic asbestos chloro...
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Carcinoma ex pleomorphic adenoma

Carcinoma ex pleomorphic adenoma is the most common of three malignant mixed tumours of salivary glands, and are thought to arise from pre-existing pleomorphic adenomas (or benign mixed tumours) 1. Epidemiology These tumours usually occur in older patients (6th to 8th decade), who have had a p...
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Carcinosarcoma

Carcinosarcomas are highly malignant biphasic tumours with both carcinomatous (epithelial) and sarcomatous (bone, cartilage, or skeletal muscle) components.  Pathology It can arise in many organs: lung 5: pulmonary carcinosarcoma oesophagus 1: oesophageal carcinosarcoma genitourinary tract ...
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Carina

The carina is part of the trachea and is an important reference point in chest imaging. Gross anatomy The carina is found at the base of the trachea and it is formed as the main bronchi divide into right and left branches. The carina usually sits in the T4/T5 plane and is at the level of the ...
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Caroticocavernous fistula

Caroticocavernous fistulas (CCF) represent abnormal communication between the carotid circulation and the cavernous sinus. They can be classified as direct or indirect which are separate conditions with different aetiologies.   Epidemiology Direct CCFs are often secondary to trauma, and as suc...
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Caroticotympanic artery

The caroticotympanic branch (tympanic branch) is a small branch from the C2 segment of the internal carotid artery. It is a vestigial remnant of the hyoid artery. It passes posterolaterally into the middle ear cavity and anastomoses with the inferior tympanic artery (a branch of the external ca...
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Carotid bifurcation

The carotid bifurcation is the point at which the common carotid artery terminates. As it does so, it forms the internal and external carotid arteries which go on to supply the head and neck. It is closely related anatomically to the carotid body, a small group of chemoreceptors and supporting ...
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Carotid body

The carotid body is located within the neck, and in close proximity to the carotid bifurcation. It is composed of a number of chemoreceptor cells and supporting matrix and detects changes in the composition of blood in the common carotid as it forms the internal and external carotid arteries. I...
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Carotid body tumour

Carotid body tumour, also known as a chemodectoma or carotid body paraganglioma, is a highly vascular glomus tumour that arises from the paraganglion cells of the carotid body. It is located at the carotid bifurcation with characteristic splaying of the ICA and ECA.  Epidemiology Typically, ca...
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Carotid canal

The carotid canal is a passage within the petrous temporal bone and transmits the internal carotid artery and sympathetic plexus. Its inferior opening is called the carotid foramen and is situated anteriorly to the jugular fossa and medially to the tympanic plate. The carotid canal is initially ...
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Carotid space

The carotid space (also known as the post-styloid parapharyngeal space) is one of the seven deep compartments of the head and neck. Gross anatomy The carotid space is a roughly cylindrical space that extends from the skull base through to the aortic arch.  It is circumscribed by all three laye...
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Carotid triangle

The carotid triangle is one of the paired triangles in the anterior triangle of the neck. The triangles of the neck are surgically focussed, first described from early dissection-based anatomical studies which predated cross-sectional anatomical description based on imaging (see deep spaces of t...
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Carotidynia

Carotidynia, also known as Fay syndrome, is a rare syndrome characterised by neck pain in the region of the carotid bifurcation. It was classified by the International Headache Society (IHS) in 1988 as an idiopathic neck pain syndrome associated with tenderness over the carotid bifurcation with...
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Castleman disease

Castleman disease, also known as angiofollicular lymph node hyperplasia or giant lymph node hyperplasia, is an uncommon benign B-cell lymphoproliferative condition. It can affect several regions of the body although commonly described as a solitary mediastinal mass. There are two distinct subty...
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Cataract

Cataract is an opacification or thickening of the lens within the globe and is the leading cause of blindness in the world 2.  Clinical presentation Visual deterioration occurs with increasing degrees of severity. The diagnosis is made clinically. Pathology Aetiology Common causes include: ...
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Cavernous sinus thrombosis

Cavernous sinus thrombosis (CST) is a rare condition, most commonly infectious in nature, and the diagnosis on imaging is not always straightforward. It has high mortality and morbidity rates. Epidemiology CST is rare with ~4.5 cases per 1,000,000 per year 5. It is the least common dural venou...
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Cebocephaly

Cebocephaly refers to a type of rare midline craniofacial anomaly where there is a single nostril (which usually ends blindly 6-7) with proboscis-like nose 8 and hypotelorism. Pathology Associations holoprosencephaly: particularly alobar holoprosencephaly trisomy 13 See also ethmocephaly ...
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Cementoblastoma

Cementoblastoma is one of many mandibular lesions is a rare tumour of the cementum, with only approximately 100 cases reported. Key to diagnosis both radiologically and histologically is attachment to the tooth root.  Terminology Cementoblastomas have been previously described in the literatur...
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Cemento-osseous dysplasia

Cemento-osseous dysplasia (COD) is a benign condition that can affect jaw. They may arise from the fibroblasts of the periodontal ligaments. Three types have been described periapical cemental dysplasia focal cemento-osseous dysplasia florid cemento-osseous dysplasia See also 2005 WHO his...
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Cemento-ossifying fibroma

Cemento-ossifying fibroma (COF) are rare, benign neoplasms that usually arise from the mandible or maxilla. They most often arise from the tooth bearing areas of these bones. Terminology In the 2005 WHO histological classification of odontogenic tumours, this tumour is referred to as "ossifyin...
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Central artery of the retina

The central artery of the retina or central retinal artery (CRA) arises from the ophthalmic artery.  Gross anatomy The central artery of the retina courses anteriorly and inferior to the optic nerve, It then pierces the dura and the arachnoid of the optic nerve. It then runs in the centre of t...
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Central base of skull

The central base of skull is a region of the skull base centred on the pituitary fossa and includes surrounding structures. Despite no single universally accepted definition of this region, it is frequently used clinically and is conceptually useful particularly when considering tumours of the ...
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Cerumen

Cerumen (or earwax) is a natural secretion produced by, and found within the external auditory canal (EAC). It has important roles as part of the first-line of defence of the ear from micro-organisms and optimising function of the tympanic membrane and EAC. Secretion Cerumen is secreted by the...
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Cervical adenitis

Cervical adenitis refers to the inflammation of lymph nodes in the neck. Epidemiology Most common cause of a paediatric neck mass following non-specific infectious/inflammatory insults. Clinical presentation In the paediatric population, a child will present with a painful cervical mass. Pa...
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Cervical lymph node groups

Cervical lymph node groups describe the anatomic position of the nodes. It differs from cervical lymph node levels, covering all lymph nodes not just those relevant to head and neck surgery.  Gross anatomy Groups described in the literature include but are not limited to:  facial group parot...
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Cervical lymph node (staging)

Cervical lymph node staging is important in a variety of tumours, especially squamous cell carcinoma of the head and neck. TNM nodal staging Nodal staging is the same for squamous cell carcinomas of most regions of the upper aerodigestive tract of the head and neck, including those of the of t...
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Cervical plexus

The cervical plexus is formed by the ventral (anterior) rami of the C1 to C5 nerve roots and innervates the diaphragm, provides motor supply to some neck muscles and cutaneous sensation to the skin of the head, neck and chest. Gross anatomy Roots anterior rami of C1 to C5 nerves Course runs...
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Cervical thymus

The cervical thymus refers to the ectopic location of thymus at the cervical level above the brachiocephalic vein. Clinical presentation A cervical thymus usually presents before adolescence as a painless unilateral midline or lateral neck mass. Pathology Aetiology Around the 4th to 5th wee...
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Chamberlain line

Chamberlain line is a line joining the back of hard palate with the opisthion on a lateral view of the craniocervical junction. Significance It helps to recognise basilar invagination which is said to be present if the tip of the dens is >3 mm above this line. McGregor developed a modificatio...
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Charcot-Leyden crystals

Charcot-Leyden crystals consist of collections of bipyramidal crystalloid made up of eosinophilic membrane proteins, which occur in:  asthma other eosinophilic lung disease 2 certain cases of sinusitis (e.g. allergic fungal sinusitis) They may be detected in the sputum or sinus secretions wi...
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Cherubism

Cherubism has historically been considered a variant of fibrous dysplasia, but in reality is likely a distinct entity.  Epidemiology Cherubism is a rare disorder and the precise incidence is unknown. It is inherited in an autosomal dominant pattern 2 and has variable penetrance, with onset in ...
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Choanal atresia

Choanal atresia refers to a lack of formation of the choanal openings. It can be unilateral or bilateral. Epidemiology It frequently presents in neonates where it is one of the commonest causes of nasal obstruction in this age group. There is a recognised female predilection. The incidence is ...
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Cholesteatoma

Cholesteatoma is histologically-equivalent to an epidermoid cyst and is composed of desquamated keratinizing stratified squamous epithelium forming a mass. They usually present with conductive hearing loss. Pathology The mass is lined by epithelium (facing inwards) which continues to grow, the...
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Chondrosarcoma of the skull base

Chondrosarcomas of the base of the skull are rare compared with other skull base tumours but are an important differential diagnosis as surgical resection and management are affected by the preoperative diagnosis. Epidemiology Chondrosarcomas of the base of the skull make up only a small fract...
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Chorda tympani

The Chorda tympani is a nerve that arises from the mastoid segment of the facial nerve, carrying afferent special sensation from the anterior two-thirds of the tongue via the lingual nerve, as well as efferent parasympathetic secretomotor innervation to the submandibular and sublingual glands. ...
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Chorioretinal lacunae

Chorioretinal lacunae refer to punched out lesions in pigmented layer of retina, usually around the optic disc. It is a considered a consistent feature of Aicardi syndrome.
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Choristoma

A choristoma is simply a collection of microscopically normal cells or tissues in an abnormal location. This is different to a hamartoma which is derived only from local tissues. Examples include: adrenal choristoma (myelolipoma) nasopharyngeal choristoma facial nerve choristoma optic nerve...
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Choroidal detachment

Choroidal detachment is a detachment of the choroid from the underlying sclera due to the accumulation of fluid in the suprachoroidal space generally due to increased intraocular pressure (IOP), as observed in some settings: choroidal effusion transudative: trauma exudative: fluid accumulatin...
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Choroidal haemangioma

Choroidal haemangiomas are benign vascular hamartomatous tumours of the choroid. They present in two forms based on the extent of choroidal involvement: Circumscribed choroidal hemangioma (CCH): solitary tumour with no systemic associations. Diffuse choroidal hemangioma (DCH): usually in assoc...
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Choroidal osteoma

Choroidal osteomas are rare benign calcific masses of the globe.  Epidemiology Choroidal osteomas are typically found in young Caucasian women 1. A number of familial cases have been reported 3.  Clinical presentation These lesions are usually unilateral (75%), and result in painless and gra...
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Chronic invasive fungal sinusitis

Chronic invasive fungal sinusitis is a form of invasive fungal sinusitis.  Clinical presentation The condition has a more prolonged course than acute invasive fungal sinusitis, usually more than 12 weeks 5. Patients are usually immunocompetent or have a milder level of immunocompromise. There ...
Article

Chronic otomastoiditis

Chronic otomastoiditis (COM) should be considered a separate entity from acute otomastoiditis, and is defined as persistent or recurrent inflammation of the middle ear and mastoid, lasting usually for a minimum of 12 weeks, and resulting in permanent perforation of the tympanic membrane. Pathol...
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Chronic otomastoiditis with ossicular erosions

Chronic otomastoiditis with ossicular erosions (aka) non-cholesteatomatous ossicular erosion or post inflammatory ossicular erosions is defined by the erosive changes involving the ossicles in the absence of cholesteatoma in a patient with a history of chronic otomastoiditis. Radiographic featu...
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Chronic otomastoiditis with tympanosclerosis

Chronic otomastoiditis with tympanosclerosis represents calcific or bony middle ear foci secondary to suppurative chronic otomastoiditis. Radiographic features Common locations of calcifications include: tympanic membrane ossicle surface stapes footplate muscle tendons ossicle ligaments ...
Article

Chronic sinusitis

Chronic sinusitis refers to ongoing long-term sinus infection-inflammation that often develops secondary to a prolonged/refractory acute sinus infection. Epidemiology It most commonly affects young to middle-aged adults but can uncommonly also affect children. Clinical presentation Chronic s...
Article

Chvostek sign

Chvostek sign is the facial twitch obtained by tapping the distribution of the facial nerve in front of the tragus. It is caused by mechanical irritability of peripheral nerves. It is indicative of hypocalcemia and is the most reliable test for hypocalcemia.
Article

Ciliary ganglion

The ciliary ganglion is one of four parasympathetic ganglia of the head and neck. It receives parasympathetic fibres from the oculomotor nerve. Gross anatomy smallest of the ganglia (2mm in size) located posterolaterally in the intraconal space of the orbit (towards the orbital apex) between ...
Article

Cirsoid aneurysm

Cirsoid aneurysms are rare arteriovenous malformations of the scalp and extremities.  Clinical presentation Patients often present with a slow-growing pulsatile mass and may also experience bleeding, tinnitus and/or a headache 3.  Pathology Cirsoid aneurysms develop due to an abnormal arteri...
Article

Cleft lip and palate

Cleft lip and palate is one of the commonest of neonatal facial anomalies. In ~80% of cases, the two features tend to occur together 6. Epidemiology It is estimated to occur with an incidence of ~1 in 700-to-1000 live births 1. This can increase to 4% for a sibling of a previously affected fet...
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Cleft palate

Cleft palate is a type of facial cleft. It can occur in two main aetiologically different forms: in association with a cleft lip: cleft lip +/- palate (much commoner) on its own: isolated cleft palate (rarer)
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Clival masses

The differential of a mass involving or arising from the clivus is a relatively narrow one and can be divided into whether the lesion arises from the skull base itself, the intracranial compartment above or the base of skull below. When evaluating the clivus it is important to compare the marro...

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