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.

21 results found

ACR Thyroid Imaging Reporting and Data System (ACR TI-RADS)

ACR TI-RADS is a reporting system for thyroid nodules on ultrasound proposed by the American College of Radiology (ACR) 1. This uses a standardised scoring system for reports providing users with recommendations for when to use fine needle aspiration (FNA) or ultrasound follow-up of suspicious ...

Anterior cord syndrome

Anterior cord syndrome (also known as Beck's syndrome or anterior spinal artery syndrome) is a clinical subset of spinal cord injury syndromes, due to ischaemia/infarction of the anterior two-thirds of the spinal cord, typically sparing the posterior third. Clinical presentation Patient presen...

Assessment of thyroid lesions (ultrasound)

Ultrasound along with nuclear medicine, is an important modality for assessment of thyroid lesions, and it is also frequently used to guide biopsy. Diagnostic criteria for thyroid nodules continue to evolve with improving ultrasound technology. Radiographic features Ultrasound Calcification ...

ATA guidelines for assessment of thyroid nodules

The American Thyroid Association (ATA) guidelines for assessment of thyroid nodules are meant to improve inter- and intra-reader consistency during assessment of thyroid nodules on ultrasound, and to facilitate communication with referring endocrinologists. The 2015 guidelines stress the import...

Bimastoid line

The bimastoid line has been described and used to evaluate basilar invagination on frontal skull plain film and coronal reconstructed CT image. The bimastoid line is drawn between the inferior tips of the of mastoid processes bilaterally. The tip of the odontoid process of C2 normally projects ...

Canadian C-spine rules

Canadian C-spine rules are a set of guidelines that help a clinician decide if cervical spine imaging is not appropriate for a trauma patient in the emergency department. The patient must be alert and stable. There are three rules: is there any high-risk factor present that requires cervical s...

CT head (subdural window)

The subdural (blood) window can be used when reviewing a CT brain as it makes intracranial haemorrhage more conspicuous, and may help in the detection of thin acute subdural haematomas that are against the calvarium. It is a wider setting than the standard non-contrast window, and there are a nu...

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 ...

Denver criteria for blunt cerebrovascular injury

The Denver criteria are a set of screening criteria for blunt cerebrovascular injury (BCVI) in trauma used to reduce the need for CT angiography and its associated radiation exposure.  Screening criteria The screening protocol criteria 1,3 for BCVI are divided into signs and symptoms of BCVI a...

Digastric line

The digastric (or biventer) line has been described and used to evaluate basilar invagination on frontal skull plain film and coronal recontructed CT image.  The digastric line is drawn between right and left digastric grooves. The tip of the odontoid process and atlanto-occipital joint normall...

Dolan's lines

Dolan's lines are the collective name given to three lines described by Dolan and Jacoby 1 that aid in evaluating for maxillofacial fractures on an occipitomental skull radiograph. They are usually used as an adjunct to McGrigor-Campbell lines. orbital line traces the inner margins of the later...


Epistaxis (nosebleed) is very common and has a broad differential diagnosis in clinical practice. In clinical practice, anterior epistaxis are mainly located in Kiesselbach's plexus and posterior epistaxis (5% of all epistaxis) in Woodruff's plexus. Epidemiology Epistaxis is very common, with ...

Functional endoscopic sinus surgery

Functional endoscopic sinus surgery (FESS) is performed intranasally using a rigid endoscope. Its primary objective is to restore physiological ventilation and mucociliary transport 1. Sinus imaging is crucial in preoperative planning and is increasingly being used intraoperatively. Indication...

Localisation of parotid lesions

The parotid gland consists of a superficial and deep lobe. Determining the location and extent of the lesions affecting the gland is an essential aspect of imaging and vital information which needs to be conveyed to the surgeon. Method of evaluation The following lines are proposed for differe...

McGill Thyroid Nodule Score (MTNS)

The McGill Thyroid Nodule Score (MTNS) is a scoring system developed to estimate the risk of malignancy of thyroid nodules.1 Scoring system The MTNS is based on 22 parameters: eight clinical or laboratory parameters gender (male): 1 point age (>45 years old): 1 point palpable nodule (prese...

Multiphase CT angiography in acute ischaemic stroke

Multiphase CT angiography is an evolving imaging technique in acute ischaemic stroke. The technique aims to quickly and reliably identify brain which is potentially salvageable with intervention. Brain tissue viability depends on many factors, with this technique assessing collateral leptomening...

NEXUS criteria

NEXUS (National Emergency X-Radiography Utilization Study) is a set of validated criteria used to decide which trauma patients do not require cervical spine imaging. Trauma patients who do not require cervical spine imaging: alert and stable no focal neurologic deficit no altered level of co...

Patterns of sinonasal obstruction

Recognising patterns of sinonasal obstruction is useful to help localise the area of pathology and narrow the differential diagnosis.  Radiographic features Babbel et al described five pattern of sinonasal obstruction 1, which are readily apparent on CT: Infundibular pattern opacification of...

Radiographic assessment of basilar invagination

Five lines have been described and used by most of the radiologists to evaluate basilar invagination on frontal and lateral skull plain radiographs as well as coronal and midsaggital reconstructed CT images. This is based on the relative projection of odontoid process to these lines, which is a...

Tentorial angle

The tentorial angle is measured between a line connecting the nasion with the tuberculum sellae and the the angle of the straight sinus. Normally it should measure between 27° and 52°. Abnormalities of the posterior fossa / base of skull can alter this. For example this angle is elevated in ach...

Ultrasound-guided FNA of the thyroid

Ultrasound-guided fine needle aspiration (FNA) of the thyroid refers to a minimally invasive procedure where in which tissue samples are collected from a thyroid nodule or other suspicious thyroid lesion. It is usually done on a outpatient basis and generally complications are very minimal. Pro...

Updating… Please wait.

Alert accept

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

Alert accept Thank you for updating your details.