Items tagged “ref link”
29 results found
Fatty falx cerebri
A fatty falx cerebri is a benign entity in which there is fat within the extradural neural axis compartment located between the two visceral layers of the falx. Epidemiology According to one study, it is a common finding seen in approximately 7.3% of patients 1. This can be more common in old...
Myoepitheliomas and malignant myoepitheliomas were considered a variant of pleomorphic adenomas until 1991. However, these are also found in breast and bronchus and have gained recognition as separate entities. They account for less than 1% of salivary gland tumors, only rarely undergo malignant...
Recurrent artery of Heubner
Recurrent artery of Heubner, also known as the medial striate artery or long central artery, is the largest perforating branch from the proximal anterior cerebral artery (ACA) and is the only one routinely seen on angiography. Gross anatomy Origin and course Its origin is near the A1-ACOM-A2 ...
Anterior cerebral artery
The anterior cerebral artery (ACA) along with the middle cerebral artery (MCA) forms at the termination of the internal carotid artery (ICA). It is the smaller of the two, and arches anteromedially to pass anterior to the genu of the corpus callosum, dividing as it does so into its two major bra...
The pericallosal artery is the distal portion of the anterior cerebral artery (ACA) that courses over the superior surface of the body of the corpus callosum in the pericallosal cistern. It gives off many small branches to the corpus callosum, forming the pericallosal moustache. Some authors de...
Equivalent dose (symbol HT) is a measure of the radiation dose to tissue where an attempt has been made to allow for the different relative biological effects of different types of ionizing radiation. In quantitative terms, equivalent dose is less fundamental than absorbed dose, but it is more b...
Coffin-Siris syndrome, first described in 1970, is a rare genetic abnormality. Coffin-Siris syndrome should not be confused with Coffin-Lowry syndrome. Epidemiology It occurs more frequently in females (with a M:F of ~4:1). Clinical presentation One of the most typical features is absence o...
A Schatzki ring, also called Schatzki-Gary ring, is symptomatically narrow esophageal B-ring occurring in the distal esophagus and usually associated with a hiatus hernia. Epidemiology Relatively common, lower esophageal rings are found in ~10% of oesophagrams. Clinical presentation Most c...
The thalamus (plural: thalami) is the largest of the structures comprising the diencephalon. Role The thalamus acts as a relay center, receiving and distributing information between the peripheries and higher centers such as the cerebral cortices. It contributes to functions such as: consciou...
Anterior spinal artery
The anterior spinal artery supplies the anterior portion of the spinal cord and arises from the vertebral artery in the region of the medulla oblongata. The two vertebral arteries (one of which is usually bigger than the other) anastamose in the midline to form a single anterior spinal artery at...
An x-ray tube functions as a specific energy converter, receiving the electrical energy and converting it into two other forms of energy: x-radiation and heat. Heat is considered the undesirable product of this conversion process; therefore x-radiation is created by taking the energy from the el...
The anode (or anticathode) is the component of the x-ray tube where x-rays are produced. It is a piece of metal, shaped in the form of a bevelled disk with the diameter between 55 and 100 mm, and thickness of 7 mm, connected to the positive side of the electrical circuit. The anode converts ener...
Toxoplasmosis vs lymphoma
Toxoplasmosis and lymphoma are frequently differential diagnoses in patients with HIV/AIDS, as these represent the most common brain lesions with mass effect in this population. As treatment is substantially different, distinguishing the two on imaging is important, particularly when the lesion ...
Computed tomography (CT) scanning, also known as, especially in the older literature and textbooks, computerized axial tomography (CAT) scanning, is a diagnostic imaging procedure that uses x-rays to build cross-sectional images ("slices") of the body. Cross-sections are reconstructed from measu...
Premature closure of a growth plate (differential)
Premature closure of a growth plate subsequently results in a shortened bone, which can occur in a number of situations. Pathology Common etiologies local hyperemia infection: osteomyelitis juvenile chronic arthritis juvenile rheumatoid arthritis hemophilia arteriovenous malformation t...
Central nervous system curriculum
The central nervous system curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core central nervous system knowledge. Definition Topics pertaining to the intracranial content (brain, pituitary, dura, intracranial vasculatures). There will be...
Cerebral venous sinus thrombosis
Published 23 Oct 2013
The Girdlestone procedure (also known as a femoral head ostectomy or Girdlestone resection arthroplasty) is an excision arthroplasty of the hip. The procedure inevitably results in limb shortening. Indications peri-prosthetic infection aseptic loosening recurrent dislocation failed interna...
Image plate artifact
Image plate artifact is caused by backscatter radiation. Backscatter radiation is transmitted through the back of the cassette to the cassette hinge where the lead coating gets weakened or cracked. To reduce backscatter, the radiographer should collimate where possible.
Slit ventricle syndrome
Slit ventricle syndrome refers to cerebrospinal fluid shunt-related symptoms in the setting of small ventricles demonstrated on radiologic studies. Clinical presentation The presence of characteristic symptoms is required to diagnose slit-ventricle syndrome and must be distinguished from slit-...