Articles

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More than 200 results
Article

CT angiography of the cerebral arteries (protocol)

CT angiography of the cerebral arteries, also known as a CTA carotids or an arch to vertex angiogram, is a non-invasive technique that allows visualization of the internal and external carotid arteries and vertebral arteries and can include just the intracranial compartment or also extend down t...
Article

Describing a bone lesion

Describing a bone lesion is an essential skill for the radiologist, used to form an accurate differential diagnosis for neoplastic entities, and occasionally non-neoplastic. In addition to patient demographics, the radiographic features of a bone lesion are often the primary determinant of non-h...
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MRI in patients with pacemaker systems

MRI in patients with cardiac implantable electronic devices (CIED) has increasingly become a requirement in radiological departments 1-8. Especially in the setting of patients with MR conditional pacemaker systems, where all the manufacturer's instructions are followed and a standardized institu...
Article

Extradural hematoma vs subdural hematoma

Differentiating extradural (EDH) from subdural (SDH) hemorrhage in the head is usually straightforward, but occasionally it can be challenging. SDHs are more common and there are a few distinguishing features which are usually reliable. Pathology History and mechanism of injury Extradural hem...
Article

Diagnostic HRCT criteria for usual interstitial pneumonia (UIP) pattern - Fleischner society guideline (2018)

In 2018, the Fleischner Society provided updated diagnostic HRCT criteria for usual interstitial pneumonia (UIP) pattern based on literature review and the expert opinion of members. As a part of this white paper, diagnostic HRCT criteria for usual interstitial pneumonia (UIP) pattern were updat...
Article

Sternoclavicular joint (ultrasound)

Ultrasound of the sternoclavicular (SC) joint can have a role along with CT and MRI in the assessment of related pathology and for intra-articular injection. Indications sternoclavicular joint arthropathy post-trauma, e.g. suspected sternoclavicular joint dislocation Normal ultrasound anatom...
Article

Bicaudate index

The bicaudate index (BCI) is the ratio of width of two lateral ventricles at the level of the head of the caudate nucleus to distance between outer tables of skull at the same level. It can be a useful marker of ventricular volume and in the diagnosis of hydrocephalus.  See also Evans' index ...
Article

Infertility in the exam

It is important to have a systematic way of approaching a case with subfertility in the exam.  Ultrasound is the initial examination of choice. Always say that you would further assess the uterus with 3D ultrasound. You may also say that in my department we would perform a sonohysterogram or HS...
Article

Cervical lymph node metastasis (radiologic criteria)

Cervical lymph node metastases refer to regional nodal involvement by cancer in the head and neck, most commonly due to squamous cell carcinoma originating from the aerodigestive tract or skin. Radiologic detection of cervical lymph node metastases is important for clinical staging and planning ...
Article

Pyrexia of unknown origin

A pyrexia of unknown origin, commonly shortened to PUO, and also known as a fever of unknown origin (FUO), was originally defined in 1961 as the condition in which the core body temperature is >38.3oC for a period of three weeks or more, with no diagnosis reached after one week of inpatient inve...
Article

Fetal abdominal circumference

Abdominal circumference (AC) is one of the basic biometric parameters used to assess fetal size. AC together with biparietal diameter, head circumference, and femur length are computed to produce an estimate of fetal weight. In the second trimester, this may be extrapolated to an estimate of ges...
Article

Cervical cerclage

Cervical cerclage is a treatment that is undertaken during pregnancy to reduce the chances of preterm labor. It involves the placement of a suture around the neck of the cervix. It aims to reduce the risk of preterm birth and provides mechanical support to keep the cervix closed 1,2. Cervical c...
Article

CT head (an approach)

The approach taken to interpreting a CT scan of the head is no doubt different depending on the circumstances and the reading clinician, however, most radiologists will go through the same steps, although order may vary. What follows is merely a suggested approach to interpreting a CT of the hea...
Article

Spinal cord tuberculoma

Spinal cord tuberculomas are rare compared to intracranial tuberculomas and can be challenging to diagnose particularly in individuals who are not from endemic areas.  Epidemiology Only 0.2% of central nervous system tuberculosis shows evidence of spinal cord involvement, and among tuberculosi...
Article

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 an outpatient basis and generally complications are very minimal. Pr...
Article

M-line of Cremin

M-line of Cremin is an imaginary line that can be used to determine the level at which the blind pouch ends in anal atresia, determining whether the anal atresia is a high or a low type. The line is drawn perpendicular to the long axis of the ischium on the lateral view and passes through the j...
Article

Retrosternal airspace

The retrosternal airspace is seen as a normal lucency between the posterior aspect of the sternum and anterior aspect of the ascending aorta on lateral chest radiographs. This space normally measures less than 2.5 cm in width. Increased retrosternal airspace is a sign of pulmonary emphysema, whi...
Article

Knee radiograph (an approach)

Knee radiographs are common and often a quick and easy diagnostic exam in the emergency setting. An efficient approach to them requires a good understanding of anatomy with review strategies to ensure an accurate diagnosis. Systematic review Choosing a search strategy and utilizing it consiste...
Article

Hysterosalpingogram

A hysterosalpingogram (HSG) is a fluoroscopic examination of the uterus and the fallopian tubes, most commonly used in the investigation of infertility or recurrent spontaneous abortions. Indications infertility: to assess uterine morphology and tubal patency Contraindications pregnancy act...
Article

Naming of organisms

Occasionally, we will refer to lifeforms in an article or case, and we adhere to standard scientific convention when it comes to naming of organisms, as set down by the International Commission on Zoological Nomenclature (ICZN) 1. As per the standard binomial system, the genus and species of the...

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