Articles
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1,953 results found
Article
Branch retinal artery occlusion
Branch retinal artery occlusion (BRAO) refers to the acute obstruction of an arteriolar branch of the central retinal artery, which can lead to retinal ischaemia and transient or permanent visual loss. The distribution affecting a branch distinguishes this disease from central retinal artery occ...
Article
Sphincter pupillae muscle
The sphincter pupillae muscle is a circular ring of smooth muscle within the iris responsible for constriction of the pupil (miosis). The structure is stimulated by the parasympathetic nervous system causing the muscle to decrease in diameter as it contracts.
Gross anatomy
The sphincter pupill...
Article
Apical periodontitis
Apical periodontitis refers to a spectrum of diseases that occur around the tooth apex and these can include 1,4:
periodontitis
chronic periodontitis
aggressive periodontitis
necrotising periodontitis
periapical granuloma
periapical abscess
periapical (radicular) cyst
Clinical presentati...
Article
Vagal schwannoma
Vagal schwannomas are uncommon benign masses that can occur anywhere along the course of the vagus nerve but most commonly occur in the cervical region.
Epidemiology
Most commonly occurs in the 3rd to 5th decades. No sex predilection 3.
Clinical presentation
Patients may be asymptomatic. Whe...
Article
Kissing carotids
The term kissing carotids refers to tortuous and elongated carotid arteries which touch in the midline. They can be found in:
retropharynx 2
intrasphenoid 1
within the pituitary fossa
within sphenoid sinuses
within sphenoid bones
The significance of kissing carotids is two-fold:
may mimi...
Article
Jugulodigastric lymph nodes
The jugulodigastric lymph nodes, also known as subdigastric lymph nodes, are deep cervical nodes located below the posterior belly of the digastric muscle and anterior to the internal jugular vein.
They are located in neck node level IIa and receive lymphatic drainage from the tonsils, pharynx,...
Article
Choanal atresia
Choanal atresia refers to a lack of formation of the choanae, the openings providing communication between the nasal cavity and nasopharynx. 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 a...
Article
Cloverleaf skull (craniosynostosis)
Cloverleaf skull, also known as kleeblattschädel syndrome or deformity, refers to a type of severe craniosynostosis that 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, corona...
Article
Persistent stapedial artery
The persistent stapedial artery (PSA) is an abnormal small vessel arising from the petrous portion of the internal carotid artery and crossing through the middle ear. It results from the failure of regression of the embryonic stapedial artery.
Epidemiology
The prevalence is thought to range f...
Article
Intracranial dermoid cyst
Intracranial dermoid cysts are uncommon lesions with characteristic imaging appearances. Dermoid cysts can be thought of as along the spectrum: from epidermoid cysts at one end (containing only desquamated squamous epithelium) and teratomas at the other (containing essentially any kind of tissue...
Article
Superior semicircular canal dehiscence syndrome
Superior semicircular canal dehiscence syndrome (SCDS) is an inner ear abnormality, where a clinical disequilibrium phenomenon is associated with the absence of the bony covering of the superior semicircular canal (SSCC).
Notably, this CT finding has also been described in ~10% of individuals w...
Article
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...
Article
Masticator space
The masticator space is the deep compartment of the head and neck that contains the muscles of mastication.
Gross anatomy
The masticator spaces are paired suprahyoid cervical spaces on each side of the face. Each space is enveloped by the superficial (investing) layer of the deep cervical fasc...
Article
Leave alone lesions - maxillodental
Maxillodental leave alone lesions are usually incidental findings that do not require treatment nor follow-up if the patient is asymptomatic.
This article includes findings from orthopantomogram, cone-beam CT, and sinus CT studies.
Do not touch:
benign lesions
tooth ankylosis
hypercementosi...
Article
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 species of Coccidioides are Coccidioides immitis and Cocc...
Article
Fallopian canal
The fallopian canal or facial nerve canal refers to a bony canal through which the facial nerve traverses the petrous temporal bone, from the internal acoustic meatus to the stylomastoid foramen.
There are three segments of the canal, corresponding to the segments of the facial nerve they cont...
Article
Orbicularis oculi muscle
The orbicularis oculi muscle is a muscle of facial expression, a ring-like muscle functioning in a number of eyelid movements.
Gross anatomy
The orbicularis oculi muscle is subdivided into orbital, palpebral and lacrimal parts. Each has defined actions.
The orbicularis oculi is secured to th...
Article
Osteoarthritis of the temporomandibular joint
Osteoarthritis of the temporomandibular joint (TMJ) is the end point of long-standing TMJ dysfunction. It is a common finding incidentally on a base of skull imaging, and it should be remembered that TMJ pain does not correlate well with osteoarthritic changes. Indeed pain from TMJ dysfunction i...
Article
Postpartum thyroiditis
Postpartum thyroiditis (PPT) is a type of thyroid inflammatory condition defined as the development of hypothyroidism, thyrotoxicosis or both in the year following childbirth in any women who did not have clinical evidence of thyroid disease before pregnancy 7. It may also occur following a spon...
Article
Black turbinate sign (nasal cavity)
The black turbinate sign refers to the non-enhancement of nasal turbinates in a patient with acute invasive fungal rhinosinusitis.
Angioinvasive fungal infection (e.g. mucormycosis or aspergillosis) involves the nasal mucosa and causes infarction of the surrounding tissue. The infarcted tissue ...