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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.

More than 200 results
Article

Subconjunctival fat prolapse

Subconjunctival fat prolapse is an acquired herniation of intraconal fat due to the weakening of the Tenon capsule by normal ageing, surgery, or trauma. It presents clinically with a fat-containing epibulbar mass in the lateral canthal area. Epidemiology  Subconjunctival fat prolapse occurs ma...
Article

Acquired cholesteatoma

Acquired cholesteatomas are far more common than congenital cholesteatomas and are almost always closely related to the tympanic membrane and pneumatised portion of the temporal bone from which most are thought to arise 9. Cholesteatomas occur far more commonly in the middle ear than in the ext...
Article

Submandibular ganglion

The submandibular ganglion is one of four parasympathetic ganglia of the head and neck. It receives parasympathetic fibres from the facial nerve. Gross anatomy small ganglion suspended from the undersurface of the lingual nerve inferior to submandibular duct sitting on the hyoglossus muscle ...
Article

Otalgia

Otalgia refers to the clinical symptoms of ear pain. It is broadly divided in two categories which are primary otalgia (~ 50% 3) - ear pain originating from causes within or near to the ear itself secondary otalgia / referred otalgia (~50% 3)- ear pain due to causes remote from the ear Pathol...
Article

Pterygopalatine ganglion

The pterygopalatine ganglion (also known as the nasal ganglion, or sphenopalatine ganglion) is one of four parasympathetic ganglia of the head and neck and largest of the peripheral parasympathetic ganglia. It receives parasympathetic fibres from the facial nerve. Gross anatomy ganglion locate...
Article

Parietal foramen

The parietal foramina are inconstant foramina on each side of the posterior aspect of the parietal bone near the sagittal suture and represent a normal anatomic variant. They transmit emissary veins, draining to the superior sagittal sinus, and occasionally a branch of the occipital artery. The ...
Article

Xerostomia

Xerostomia is the medical term for a dry mouth, and is most commonly due to hyposalivation. Epidemiology Xerostomia is the most frequently observed salivary abnormality in clinical practice 1. Clinical presentation dryness of the mouth uncomfortable swallowing vocalisation difficulties: to...
Article

Lillie-Crowe sign

The Lillie-Crowe sign is used in the diagnosis of unilateral sinus thrombophlebitis. Digital compression of the internal jugular vein on the opposite side to the thrombus causes dilatation of the retinal veins as venous drainage is now occluded bilaterally 2.
Article

Mandibular lesions

Mandibular lesions are myriad and common. The presence of teeth results in lesions that are specific to the mandible (and maxilla) and a useful classification that defines them as odontogenic or non-odontogenic. While it may often not be possible to make a diagnosis on imaging alone, this classi...
Article

Skull base angle

The skull base angle (of Boogard) allows the diagnosis of platybasia and basilar kyphosis. Several different techniques may be used on sagittal images from MRI or CT. Traditionally, basal angle measurements were based on plain skull images. With the advent and generalisation of MR imaging, it h...
Article

Chronic maxillary atelectasis

Chronic maxillary atelectasis is a descriptive term that is characterised by a persistent decrease in the maxillary sinus volume due to inward bowing of its walls. Terminology It is not considered synonymous with - but can include the term silent sinus syndrome, typically when there is also sp...
Article

Pyogenic granuloma

Pyogenic granulomas, also known as lobular capillary haemangiomas, are common lesions found arising from the skin and mucous membranes. Sometimes it may be difficult to differentiate them from malignancy, clinically or on imaging.  Terminology Despite its name, a pyogenic granuloma is not a tr...
Article

Otosyphilis

Otosyphilis, otic syphilis or syphilitic labyrinthitis is a manifestation of neurosyphilis affecting the inner ear. For a general discussion, and for links to other system-specific manifestations, please refer to the article on syphilis.  Pathology The pathological features of syphilitic laby...
Article

Laryngocele

A laryngocele is the dilatation of the saccule of the laryngeal ventricle and is unilateral in the vast majority of cases 8. On imaging, these lesions are generally characterised as well-defined, thin-walled, fluid or air-filled cystic lesions in the paraglottic space. Communication with the la...
Article

Prussak space

Prussak space is a subcomponent of the lateral epitympanic space and extends from the level of the scutum to the umbo. This space is best demonstrated on the oblique coronal image.  Gross anatomy Boundaries lateral: pars flaccida of the tympanic membrane and the scutum medial: neck of the ma...
Article

Eyelid

The eyelids cover the eyes, with an upper and lower eyelid on each side, and are covered in front with loose skin and behind with adherent conjunctiva. The lower lids possess very little mobility; the upper eyelid is elevated by levator palpebrae superioris muscle fibres and the lids are closed ...
Article

Goitre

Goitre (rarely thyromegaly) refers to enlargement of the thyroid gland. It can occur from multiple conditions. The absence of thyroid enlargement does not preclude significant thyroid pathology. The definition of goitre depends on age and sex. The upper limit of normal thyroid gland volume: ad...
Article

Pseudodacryocystitis

Pseudodacryocystitis refers to anterior ethmoidal sinus inflammation, usually with superimposed infection, extending into the adjacent lacrimal sac region and consequently giving a clinical presentation similar to dacryocystitis. Unlike dacryocystitis, clinical irrigation typically shows patenc...
Article

Sensorineural hearing loss

Sensorineural hearing loss (SNHL) refers to deafness secondary to conditions affecting the inner ear, internal acoustic canal, cerebellopontine angle, or vestibulocochlear nerve. It an be classified audiometrically into two types sensory (cochlear) neural (retrocochlear)  Pathology Conditio...
Article

Fossa of Rosenmüller

The fossa of Rosenmüller, also known as the posterolateral pharyngeal recess, is the most common site of origin for nasopharyngeal carcinoma 5. Gross anatomy It is located superior and posterior to the torus tubarius (the posterior projection of the cartilaginous portion of the Eustachian tube...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.