Articles
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68 results found
Article
Intraconal orbital lesions
Intraconal orbital lesions are broadly divided into two main groups; those with or without involvement of the optic nerves.
Lesions with optic nerve involvement:
optic nerve glioma
optic nerve meningioma
optic neuritis
pseudotumor
lymphoma and leukemia
intracranial hypertension
retinobla...
Article
Leave alone lesions - skull base
Leave alone lesions of the skull base refers to incidental findings that do not require treatment nor follow-up.
This article includes findings from brain CT, HRCT of the temporal bone, and MRI studies.
Do not touch:
arrested pneumatization of the skull base - sphenoid benign fatty lesion 1
...
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
Heterogeneous thyroid echotexture
Heterogeneous echogenicity of the thyroid gland is a non-specific finding and is associated with conditions diffusely affecting the thyroid gland. These include:
Hashimoto thyroiditis
Graves disease
The presence of heterogenous thyroid echogenicity may reduce sensitivity of detection of thyro...
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
Orbital mass
An orbital mass carries a wide differential.
Differential diagnosis
tumors
lymphoma
metastasis
lacrimal gland or duct tumors
rhabdomyosarcoma of the orbit
retinoblastoma
optic nerve meningioma
optic nerve glioma
schwannoma (of trigeminal or other cranial nerves except optic)
neurofibr...
Article
Parotid gland enlargement
Parotid gland enlargement (also known as parotidomegaly) has a wide differential given the significant breadth of pathology that can affect the parotid gland. These can be separated by a standard surgical sieve approach into infective, inflammatory, immune, neoplastic, infiltrative, and congenit...
Article
Obstruction of nasolacrimal drainage apparatus
Obstruction of nasolacrimal drainage apparatus results in epiphora and can be primary or secondary, congenital or acquired. Obstruction can occur at canalicular, lacrimal saccular, or nasolacrimal ductal (post-saccular) levels.
Causes of obstruction
Congenital obstruction
persistence of the m...
Article
Periapical radiolucency (teeth)
Periapical radiolucencies are commonly observed findings on OPG and other dental/head and neck imaging modalities.
Differential diagnosis
They can represent a number of pathologies:
periapical lucency related to apical periodontitis
periapical granuloma
periapical abscess
periapical cyst
...
Article
Focal calvarial thinning
Focal calvarial thinning can result from a number of causes. They include:
bilateral thinning of the parietal bones (normal variant) most common
arachnoid cyst
mega cisterna magna
peripherally located tumors (e.g. oligodendroglioma)
See also
calvarial thinning
calvarial thickening
Article
Leave alone lesions - paranasal sinuses
Leave alone lesions are findings that are usually discovered incidentally and do not require any specific treatment or follow-up if the patient is asymptomatic.
This article includes findings from paranasal sinus CT and MRI studies.
physiological process
nasal cycle
anatomical variants
conc...
Article
Temporomandibular joint effusion
Temporomandibular joint (TMJ) effusions are unusual in asymptomatic patients, and thus should trigger a careful search for underlying pathology. It usually precedes osteoarthritis of the TMJ. Effusions are seen in:
TMJ dysfunction
septic arthritis
rheumatoid arthritis (RA)
Radiographic featu...
Article
Congenital calvarial defects
Congenital calvarial defects are a group of disorders characterized 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...
Article
Hyperattenuating paranasal sinus opacification
Hyperattenuating paranasal sinus opacification can arise in a number of situations:
fungal sinus disease
inspissated secretions
acute hemorrhage into sinus (hemosinus)
Differential diagnosis
In some situations can consider early calcification within the sinus - intrasinus calcification.
Article
Differential diagnosis for calcified masses in the mandible
Differential diagnosis for calcified masses in the mandible includes:
calcifying odontogenic cyst (Gorlin cyst)
calcifying epithelial odontogenic tumor (Pindborg tumor)
fibrous dysplasia
foreign body
odontoma
cemento-ossifying fibroma
osteoma
synovial osteochondromatosis
focal sclerosi...
Article
Orbital vascular lesions
Orbital vascular lesions may be difficult to distinguish on imaging. However, the following conditions have been described:
arteriovenous malformation (AVM)
capillary hemangioma
cavernous hemangioma
orbital lymphangioma / lymphangiovenous malformation / venolymphatic malformation
orbital ve...
Article
Developmental orbital cysts
Developmental orbital cysts correspond to a heterogeneous group of congenital orbital developmental anomalies with a cystic component, ranging from closed sacs lined by an ectodermal epithelium, such as epidermoid and dermoid, to neoplasms such as teratoma 1:
choristoma: benign tumors formed by...
Article
Middle ear tumors
There are a range of middle ear tumors, which are more likely to be benign than malignant.
Pathology
The three most common middle ear tumors are (not in any particular order as there are differences in the literature) 1-3:
tympanic paraganglioma
congenital cholesteatoma
middle ear schwann...
Article
Hypotelorism
Hypotelorism refers to an abnormal decrease in distance between any two organs although some authors use the term synonymously with orbital hypotelorism meaning an abnormal decrease in the distance between the two eyes (the eyes appear too close together). The article mainly focuses on the latte...
Article
Lacrimal sac mass
Lacrimal sac masses are very uncommon and more commonly have a malignant (~80%) rather than benign (~20%) etiology.
Pathology
Etiology
inflammatory
granulomatosis with polyangiitis
sarcoidosis
orbital pseudotumor
IgG4-related disease
Sjogren syndrome
neoplastic
epithelial tumors
beni...
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