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.

1,393 results found
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...
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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.
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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 ...
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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...
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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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Clivus

The clivus is the sloping midline surface of the occipital bone anterior to the foramen magnum. Specifically it is located in the basiocciput. At the clivus, the occipital bone has articulations with the sphenoid and petrous part of temporal bone1. Inferiorly the clivus is flanked be the rounde...
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Cloquet's canal

Cloquet's canal, also known as the hyaloid canal or Stilling's canal, is a transparent canal that runs from the optic nerve disc to the lens traversing the vitreous body. It serves as a perivascular sheath surrounding the hyaloid artery in the embryonic eye. History and etymology Hippolyte Clo...
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Cloverleaf skull

Cloverleaf skull, also known as kleeblattschädel, refers to a type of severe craniosynostosis which gives the skull a cloverleaf shape. It is very rare, with less than 130 case reports globally. It typically results from intrauterine premature closure of the sagittal, coronal and lambdoid suture...
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Coalescent mastoiditis

Coalescent mastoiditis is simply the term given to acute otomastoiditis when mucoperiosteal disease extends to involve the bone. The septae which normally separate one mastoid air cell from another are resorbed. This change is only easily appreciated on thin section bone-algorithm through the te...
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Coca-Cola bottle sign (thyroid eye disease)

The Coca-Cola bottle sign refers to the appearance of the muscles of the orbit in thyroid eye disease.  The belly of the muscle enlarges with sparing of the tendinous insertion, giving the appearance of the traditional Coca-Cola bottle. The enlargement of the muscles follows the I'M SLOW format...
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Coccidioidomycosis

Coccidioidomycosis refers to an infection caused by the dimorphic fungus Coccidioides spp, usually localised to the lungs. This disease is not to be confused with the similarly named paracoccidioidomycosis. Epidemiology The most common forms of Coccidioides spp are Coccidioides immitis and Coc...
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Cochlea

The cochlea is part of the inner ear osseous labyrinth found in the petrous temporal bone.  Gross anatomy The cochlea is a shell-shaped spiral that turns between two-and-a-half and two-and-three-quarters times around the modiolus (a central column of porous bone). The spiral of the cochlea is...
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Cochlear anomalies (classification)

Cochlear anomalies are a variety of congenital anomalies which, depending on the exact time at which an insult occurs during embryogenesis, may have different manifestations. Terminology is often used imprecisely leading to confusion not only among clinicians, but also in the literature. Classi...
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Cochlear aplasia

Cochlear aplasia, or complete absence of the cochlea is a rare anomaly which accounts for only 3% of cochlear malformations.1 Radiographic features complete absence of the cochlea. Dense otic bone is seen at the anatomical site of the cochlea 2 cochlear nerve canal and cochlear nerve are abse...
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Cochlear duct

The cochlear duct (also known as the scala media) is housed centrally in the cochlea which is part of the inner ear along with the vestibular apparatus 1,4. The cochlea is located in the bony labyrinth, which is found in the temporal bone 2. Gross anatomy The cochlear duct is a cavity filled w...
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Cochlear hypoplasia

Cochlear hypoplasia is defined by small underdeveloped cochlea <2 turns. Radiographic features a small cochlear bud of variable length (usually 1–3 mm).  It has only one turn or a partial turn is seen cochlear nerve often hypoplastic or absent cochlear nerve canal: absent, narrow or normal ...
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Cochleariform process

Thin osseous septum separating the semicanal for tensor tympani and the bony Eustachian tube.
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Cochlear implant

Cochlear implants (CI) are a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing. Unlike conventional hearing aids, the cochlear implant does not amplify sound, but works by directly stimulating any functioning audi...
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Cochlear incomplete partition

Cochlear incomplete partition is a group of cochlear malformations associated with variable degree of inner ear architecture defects. It is classified in three groups: cochlear incomplete partition type I (IP-I) a severe form of IP-I is known as cystic cochleovestibular malformation cochlear...
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Cochlear incomplete partition type I

Cochlear incomplete partition type I  (IP-I) is a type of cochlear anomaly associated with sensorineural hearing loss. Radiographic features CT The main findings on CT are: absent modiolus absent interscalar septum wide (most common) or normal cochlear nerve canal Absence of these structu...
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Cochlear incomplete partition type II

Cochlear incomplete partition type II  (IP-II) is a type of cochlear anomaly associated with sensorineural hearing loss. It should not be confused with Mondini anomaly, which his an historic term for a combination of IP-II and large vestibular aqueduct. Radiographic features CT On CT, the co...
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Cochlear incomplete partition type III

Cochlear incomplete partition type III (IP-III), also termed X-linked deafness, is a rare type of genetic cochlear anomaly associated with mixed conductive and sensorineural hearing loss.  Pathology It is caused a mutation in the POU3F4 gene located on the X chromosome. Clinical presentation ...
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Cochlear promontory

The cochlear promontory is the name given to the bone that overlies the basal turn of the cochlea protruding into the middle ear cavity.  Related pathology glomus tympanicum paragangliomas typically arise in the region of the cochlear promonotory
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Cogan syndrome

Cogan syndrome is a rare vasculitis of children and young adults which primarily characterised by 1,4,6: inflammatory eye disease (ocular keratitis, uveitis, scleritis, optic neuritis) 6 audiovestibular symptoms (similar to Meniere disease) 6 However, it can potentially affect a multitude of ...
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COL4A1-related disorders

COL4A1-related disorders are a group of autosomal dominant disorders caused by a mutation in the COL4A1 gene. Epidemiology The exact prevalence is unknown, but the group of disorders is considered to be under-recognised, especially asymptomatic variants 1. Clinical presentation The clinical ...
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Collet-Sicard syndrome

Collet-Sicard syndrome is a constellation of cranial nerve palsies due to a lesion at the jugular foramen such as a glomus jugulare tumour or schwannoma. It consists of : Vernet syndrome, consisting of motor paralysis of glossopharyngeal nerve (CN IX) vagus nerve (CN X) accessory nerve (CN X...
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Colliscalene triangle

The colliscalene triangle is an important anatomical region of the neck, situated medial to the scalenus anterior muscle. Gross anatomy Boundaries medial: lateral border of longus colli lateral: medial border of scalenus anterior inferior: first part of the subclavian artery apex: carotid ...
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Colloid nodule (thyroid)

Colloid nodules are non-neoplastic benign nodules occurring within the thyroid gland. They form the vast majority of nodular thyroid disease. Pathology Colloid nodules are composed of irregularly enlarged follicles containing abundant colloid. Some colloid nodules can be cystic (cystic colloid...
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Coloboma

Coloboma is collective term encompassing any focal discontinuity in the structure of the eye, and should not be confused with staphylomas, which are due to choroidal thinning.  Pathology Most commonly colobomas are due to failure of closure of the choroidal fissure posteriorly. Typically colob...
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Columella

The columella is the most anteroinferior portion of the nasal septum and forms the central fleshy portion between the two nostrils when looking at someone's nose. It is a single midline structure composed of cartilage and overlying skin, extending posteriorly from the tip of the nose. The latera...
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Common carotid artery

The common carotid artery is a paired structure that supplies blood to the head and neck.  Summary origin: left: branch of the aortic arch right: branch of the brachiocephalic trunk course: posterior to sternoclavicular joint, lateral to thyroid and trachea supply: head and neck main bran...
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Common cavity malformation

Common cavity malformation is defined by the absence of the normal differentiation between the cochlea and vestibule, replaced instead by a cystic structure (i.e. the 'common cavity'). It accounts for about 25% of cochlear malformations 1.  Radiographic features confluence of the cochlea, vest...
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Common facial vein

The common facial vein is formed by the joining of the facial vein and anterior branch of the retromandibular vein. It is part of the venous drainage system of the face. Summary origin and termination: the facial vein (along with the facial artery) pierces the deep investing fascia of the neck...
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Common variable immunodeficiency

Common variable immunodeficiency (CVID) is a condition that is associated with an impaired immune system. It is considered the most common symptomatic primary immunodeficiency, and is characterised by recurrent respiratory tract infections. Clinical presentation The commonest presentation is t...
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Complex midfacial fracture

Complex midfacial fractures consist of multiple facial fractures that cannot be classified as any of the defined complex facial fracture (e.g. Le Fort fracture, zygomaticomaxillary complex fracture, naso-orbital-ethmoid fracture).
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Complications of petrous temporal bone fracture (mnemonic)

A handy mnemonic to recall the complications of transverse and longitudinal petrous temporal bone fractures is: listen carefully to something funny Mnemonic listen carefully = longitudinal / conductive hearing loss to something funny = transverse / sensorineural hearing loss and facial nerve...
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Concha bullosa

Concha bullosa (plural: conchae bullosae) (also known as middle turbinate pneumatisation) is a common finding and although associated with deviation of the nasal septum, it is usually of little clinical importance. Epidemiology Concha bullosa is a normal variant and is one of the most common v...
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Conductive hearing loss

Conductive hearing loss is caused by a range of developmental, congenital or acquired pathology to the external, middle or inner ear. Pathology Essentially any process that obstructs or disrupts the passage of sound waves through the outer or middle ear can cause conductive hearing loss and th...
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Condylar canal

The condylar canal, or canalis condylaris, is a skull base canal in the posterior cranial fossa, located in the condylar fossa. Summary location: in the condylar fossa of the posterior cranial fossa, posterior to the occipital condyles contents emissary veins, connecting the sigmoid sinus to...
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Condylar process fractures

Condylar process fractures are fractures of the condylar process of the mandible. The condylar process of the mandible is involved in around 30% of all mandibular fractures. Condylar fractures are classified according to the location of the fracture and the direction displacement of the condyle...
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Congenital absence of the internal carotid artery

Congenital absence of the internal carotid artery (ICA) is a rare anomaly that occurs in less than 0.01% of the population. It encompasses agenesis, aplasia, and hypoplasia 1. The most common type of collateral flow is through the circle of Willis, through the anterior communicating artery (ACO...
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Congenital calvarial defects

Congenital calvarial defects are a group of disorders characterised by congenital calvarial bone defects that vary in severity. Radiographic features CT with 3D shaded surface reformats is the best imaging tool as it demonstrates calvarial defects and bone margins: parietal foramina parietal...
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Congenital cataract

Congenital cataracts are a major cause of blindness with early detection the most important factor in reducing impact on future vision.  Epidemiology Incidence is ~3 per 100,000 in the United Kingdom 1. Will be higher in areas with increased rates of congenital infection 5. Risk factors low ...
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Congenital cervical teratoma

Congenital cervical teratoma refers to a teratoma arising in the cervical region. They are thought to account for ~3% of teratomas in childhood/infancy 3. Epidemiology The estimated occurrence in neonates is ~1:20,000-40,000 live births 8. Clinical presentation Most tumours are diagnosed at ...
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Congenital cholesteatoma

Congenital cholesteatomas are identical to epidermoid cysts, differing only in name and location.  Pathology They are intraosseous inclusions of ectoderm, and are therefore comprised of keratin debris and cholesterol. Characteristically, they are located at the petrous apex. In contrast middle...
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Congenital goitre

Congenital goitre is a rare cause of neck swelling in neonates and is demonstrated as diffuse/nodular thyroid gland enlargement. Epidemiology It is a common endocrine disease in newborns and affects approximately 1:2000-4000 live births. Clinical presentation There may be a difficult vaginal...
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Congenital granular cell myoblastoma

A congenital granular cell myoblastoma (also known as congenital epulis) is a very rare benign tumour which classically presents in the fetal-neonatal population. Epidemiology It occurs almost exclusively in females when it presents in the fetal-neonatal population although no such predilectio...
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Congenital hypothyroidism

Congenital hypothyroidism (CHT), previously known as cretinism, can be of thyroidal or central (hypothalamic/pituitary) origin and can have a widely diverse molecular aetiology. Clinical presentation Most children are asymptomatic at birth and are diagnosed after screening. In untreated CHT pa...
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Congenital hypothyroidism (mnemonic)

The features of an infant with congenital hypothyroidism can be recalled with the following mnemonic: 5 Ps of congenital hypothyroidism Mnemonic P: pot belly P: pallor P: puffy face P: protruding umbilicus P: poked out tongue
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Congenital ossicular anomalies

Congenital anomalies of the ossicles are most frequently associated with external ear abnormalities also, although they can occur in isolation.  They cause conductive hearing loss (CHL). When bilateral they are most frequently genetic, with autosomal dominant inheritance, whereas unilateral a...
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Conjunctiva

The conjunctiva is a transparent membrane is attached at the margins of the cornea. It is loosely attached to the sclera and thence reflected over the inner surface of the eyelids. It is firmly attached to the tarsal plates and blends with the skin at the margins of the lids.  Nerve supply ner...
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Convexal subarachnoid haemorrhage

Convexal subarachnoid haemorrhages (cSAH) are nontraumatic intracranial haemorrhages that occur within the surface sulci of the brain (c.f. basal cisternal distribution of aneurysmal SAH). There are various causes of convexal SAH, some of which include: dural venous sinus thromboses cortical ...
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Convoluted cerebriform pattern

A convoluted cerebriform pattern is a term used to denote the appearance of a sinonasal inverted papilloma on MRI. The appearance is seen on both T2 and post contrast T1 images and appears as alternating roughly parallel lines of high and low signal intensity. This sign has been reported as pre...
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Corniculate cartilage

The corniculate cartilages are paired, elastic and accessory cartilages of the larynx that lie superior to and articulate with the apices of the arytenoid cartilages. They are components of the laryngeal cartilages. The word 'corniculate' comes from the latin word 'cornu' meaning horn-like.
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Coronal suture

The coronal suture is the cranial suture formed between the two parietal bones and the frontal bone. At the junction of coronal, sagittal and frontal sutures is the anterior fontanelle which is open at birth and usually fuses at around 18-24 months after birth. Fusion of the coronal suture occu...
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Corrugator supercilii

The corrugator supercilii are two small, triangular muscles that allow facial expression through movement of the eyebrows, including frowning. They originate from the medial end of the supraorbital margins and insert deep to and can cause traction on the skin over the middle of the supraorbital ...
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Costocervical trunk

The costocervical trunk is one of the branches of the second part of the subclavian artery. It arises from the posterior wall of the subclavian artery, posterior or medial to the anterior scalene muscle and courses posterosuperiorly across the suprapleural membrane where it divides into 2 branc...
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Cranial vault

The cranial vault, also known as the skull vault, skullcap or calvaria, is the cranial space that encases and protects the brain together with the base of the skull (chondrocranium). The cranial vault and the base of skull together form the neurocranium. Terminology Although commonly seen in r...
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Craniofacial fibrous dysplasia

Craniofacial fibrous dysplasia is one of four types of fibrous dysplasia and is characterised, as the name suggests, by involvement of the skull and facial bones. For a general discussion of the underlying pathology, refer to the parent article fibrous dysplasia. Terminology Although the term...
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Craniotomy

Craniotomy is a surgical procedure where a piece of calvarial bone is removed to allow intracranial exposure. The bone flap is replaced at the end of the procedure, usually secured with microplates and screws. If the bone flap is not replaced it is either a craniectomy or cranioplasty.  Classif...
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Cribriform plate

The cribriform plate is a sieve-like structure between the anterior cranial fossa and the nasal cavity. It is a part of ethmoid bone and supports the olfactory bulb, which lies in the olfactory fossa. It is perforated by foramina for the passage of the olfactory nerves and the anterior ethmoidal...
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Cricoid cartilage

The cricoid cartilage is a ring shaped structure that sits just below the thyroid cartilage. It is the only complete cartilaginous ring of the whole airway. Gross Anatomy The anterior portion is called the arch and the posterior quadrangular shaped portion is the lamina. It articulates with th...
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Cricopharyngeal muscle spasm

Cricopharyngeal muscle spasm is also known as cricopharyngeal achalasia, although some authors distinguish between these entities, and may present as a cause of dysphagia. Terminology There is confusing use of the terms cricopharyngeal muscle spasm, cricopharyngeal achalasia and cricopharyngea...
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Crista galli

The crista galli is a thick, midline, smooth triangular process arising from the superior surface of the ethmoid bone, projecting into the anterior cranial fossa. It separates the olfactory bulbs, which lie either side of it in the olfactory fossae of the cribriform plate. It serves as an anteri...
Article

Crystalline lens

The crystalline lens (or simply, the lens) is in the ocular globe between the posterior chamber and the vitreous body. It is transparent and biconvex in morphology, and aids the focusing of light onto the retina.  Gross anatomy Location The lens lies in the globe at the posterior aspect of th...
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CSF otorrhoea

CSF otorrhoea is defined as leakage of cerebrospinal fluid (CSF) from the subarachnoid space into the middle ear cavity or mastoid air cells (cf. CSF rhinorrhoea) Epidemiology There are a number of underlying causes, and thus no specific demographic is affected.  Clinical presentation Patien...
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CT polytrauma (technique)

CT polytrauma/multitrauma, also called trauma CT, whole body CT (WBCT) or panscan, is an increasingly used investigation in patients with multiple injuries sustained after significant trauma. Clinical assessment and mechanism of injury may underestimate injury severity by 30% 8. There is some e...
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Cuneiform cartilage

The cuneiform cartilage is a small, paired cartilage which resides in the aryepiglottic fold. It takes the form of a club-like nodule, visible as an elevation beneath the mucosa (the cuneiform tubercle) anterosuperior to the corniculate cartilages. History and etymology The word cuneiform deri...
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Cutis verticis gyrata

Cutis verticis gyrata is a rare progressive dermatological condition characterised by excessive skin folds in the scalp, resembling the surface of the cerebral cortex. Epidemiology It occurs more commonly in males, with a male-to-female ratio of approximately 5:1 1. Clinical presentation Pat...
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Cystic hygroma

Cystic hygroma, also known as cystic or nuchal lymphangioma, refers to the cystic variety of congenital lymphangioma which, most commonly, occur in the cervicofacial regions, particularly at the posterior cervical triangle.  Epidemiology  They usually occur in the fetal/infantile and paediatri...
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Cystic mass adjacent to the angle of mandible (differential)

The differential diagnosis of a cystic mass adjacent to the angle of mandible includes: 2nd branchial cleft cyst lymphatic malformation (lymphangioma) cystic lymphadenopathy from tuberculosis from metastatic squamous cell carcinoma  from metastatic papillary thyroid cancer See also cys...
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Cystic (necrotic) lymph nodes

Cystic or necrotic appearing lymph nodes can be caused by a number of infectious, inflammatory or malignant conditions: Systemic squamous cell carcinoma metastases treated lymphoma leukemia plasmacytoid T-cell leukemia acute myeloid leukemia viral lymphadenitis herpes simplex lymphadenit...
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Cystic parotid lesions

The differential for cystic parotid lesions includes: bilateral cystic parotid lesions Warthin tumour benign lymphoepithelial lesions of HIV Sjögren syndrome sialocoeles unilateral cystic parotid lesion(s) Warthin tumour sialocoele first branchial cleft cyst: parotid lymphoepithelial cy...
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Cytomegalovirus retinitis

Cytomegalovirus retinitis is a late complication of cytomegalovirus (CMV) infection, usually occurring in immunosuppressed patients. It is an acquired immune deficiency syndrome (AIDS) defining illness. Epidemiology The reported incidence and prevalence of CMV retinitis varies with geographica...
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Dacryoadenitis

Dacryoadenitis is infection of the lacrimal gland results in diffuse homogeneous enlargement, which can sometimes compress the globe. Most common organisms are Staphylococcus aureus, mumps, infectious mononucleosis, and influenza virus.
Article

Dacryocystitis

Dacryocystitis is the inflammation of the nasolacrimal sac related to impairment in the lacrimal drainage system and superimposed infection.  Epidemiology Dacryocystitis has a bimodal distribution: neonates due to congenital abnormalities and, when acquired, usually affect individuals older th...
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Dacryocystocele

Dacryocystoceles are caused by obstruction of both the proximal and distal ends of the nasolacrimal duct. An imperforate Hasner membrane causes the distal blockage, but the cause of proximal obstruction is less clearly understood. Epidemiology Dacryocystoceles, although rare, are the second mo...
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Dacryocystography

Dacryocystography is a fluoroscopic contrast examination of the nasolacrimal apparatus. The duct is cannulated enabling iodinated contrast to be instilled into the nasolacrimal system. Indications The most frequent indication is epiphora: excessive tearing or watering of the eyes. Technique ...
Article

Danger space

The danger space is a potential space located behind the true retropharyngeal space, which connects the deep cervical spaces to the mediastinum.  Gross anatomy Boundaries anteriorly: alar fascia posteriorly: prevertebral layer of the deep cervical fascia superiorly: clivus inferiorly: post...
Article

Deep auricular artery

The deep auricular artery is the first named branch of the maxillary artery and passes through the bony or cartilaginous wall of the external acoustic meatus to supply the skin of that canal and part of the tympanic membrane. It can sometimes contribute a small branch to the arterial supply of t...
Article

Deep brain ultrasound therapy

Deep brain ultrasound (DBUS) therapy is a form of precision medicine using a technique based on the principle of high-intensity focused ultrasound (HIFU), also referred to as focused ultrasound surgery (FUS). Technique The method combines two main components 1: guidance component MRI of the ...
Article

Deep cervical fascia

The deep cervical fascia consists of 3 separate but related fascial layers that encircle structures in the neck and allow anatomic compartmentalisation. These layers cannot be visualized directly by cross sectional imaging. All 3 layers meet to form the carotid sheath. From superficial to deep, ...
Article

Deep petrosal nerve

The deep petrosal nerve transmits post-ganglionic sympathetic fibres from the internal carotid plexus to the Vidian nerve on its way to the pterygopalatine ganglion. Gross anatomy The nerve begins at the internal carotid plexus and runs alongside the lateral aspect of the internal carotid arte...
Article

Deep spaces of the head and neck

Head and neck anatomy is described in slightly different terms in the radiology literature reflecting the importance of fascia lined spaces in confining various pathologies. As such the neck has been divided into a number of 'deep spaces' which overlap with traditional anatomical description. A...
Article

Deep temporal branches

The deep temporal arteries (anterior and posterior) are branches from the second part of the maxillary artery. They ascend between the temporalis muscle and the pericranium supplying the overlying muscle. The anterior branch communicates with the lacrimal artery by means of small branches which...
Article

Deep temporal nerves

The deep temporal nerves are a pair of motor branches of the anterior division of the mandibular division of the trigeminal nerve. It should not be confused with the temporal branch of the facial nerve. Gross anatomy The two deep temporal nerves divide off the anterior division and course abov...
Article

Dehiscence

Dehiscence is a general term referring to 'splitting open' and is used in a variety of contexts in medicine generally and radiology more specifically.  The two most common usages are: splitting open of a wound (e.g. sternal dehiscence) loss of bone separating one structure from another (e.g. ...
Article

Dehiscent jugular bulb

Dehiscent jugular bulbs are present when the sigmoid plate between a high riding jugular bulb and the middle ear is absent, allowing the wall of the jugular bulb to bulge into the middle ear cavity. Epidemiology The estimated incidence is ~5% (range 3.5-7%) of the symptomatic population (e.g. ...
Article

Delphian node

The Delphian (prelaryngeal/precricoid) node is one of the cervical lymph node groups that comprise level VI cervical lymph nodes and is not routinely excised in radical neck dissections. Gross anatomy It is located between the cricothyroid muscles, above the thyroid isthmus, lying directly ant...
Article

Dental abscess

Dental (periapical) abscess is an acute infection of the periapical tissue around the root of the tooth. Clinical presentation Patients may present with pain, oedema, and purulent discharge localised to the site of pathology with or without fever and tender cervical lymphadenopathy 1. Patholo...
Article

Dental caries

Dental caries are cavities in teeth ('caries' is both the singular and plural form). They are very common and can lead to serious morbidity.  Pathology Focal enamel and dentin demineralisation result in cavity formation. There are multiple theories for their pathogenesis but contributing facto...

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