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 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.

340 results found
Article

Amniotic fluid index

The amniotic fluid index (AFI) is an estimate of the amniotic fluid volume in a pregnant uterus. It is part of the fetal biophysical profile.  Technique the uterus is divided into four imaginary quadrants with the linea nigra and a mediolateral line running through the umbilicus acting as the ...
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Amniotic fluid volume

Amniotic fluid volume (AFV) is a function both of the amount of water transferred to the gestation across the placental membrane, and the flux of water across the amnion. Physiology Change in volume through gestation The AFV undergoes characteristic changes with gestation. It progressively ri...
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Deepest vertical pocket method

The deepest (maximal) vertical pocket (DVP) depth is considered a reliable method for assessing amniotic fluid volume on ultrasound 1,2. It is performed by assessing a pocket of a maximal depth of amniotic fluid which is free of an umbilical cord and fetal parts. The usually accepted values are...
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Two diameter pocket method

The two diameter pocket (TDP) method is an alternative method of assessing amniotic fluid volumes on ultrasound. However, it is not thought to be a good predictor of adverse neonatal outcome 2. Sonographic assessment According to this method 1,2: TDP <15 cm2: indicative of oligohydramnios TD...
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Neonatal pneumothorax

Neonatal pneumothorax describes pneumothoraces occurring in neonates. It is a life threatening condition, associated with high morbidity and mortality. The diagnosis is a challenge especially when the amount of air is small and may accumulate along the anterior or medial pleural space. Epidemio...
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Cardiac MRI

Cardiac MRI consists of using MRI to study heart anatomy, physiology, and pathology. Advantages In comparison to other techniques, cardiac MRI offers: improved soft tissue definition protocol can be tailored to likely differential diagnoses a large number of sequences are available dynamic...
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Interscalene brachial plexus block

An interscalene brachial plexus block is indicated for procedures involving the shoulder and upper arm. History Ultrasound-guided brachial plexus nerve blocks entered the literature in 1989, when Ting et al. detailed their success with axillary nerve blocks in 10 patients 3. Indications redu...
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Sleeve gastrectomy complications

Complications related to sleeve gastrectomy are often evaluated by imaging. For details about surgical procedure, please see the sleeve gastrectomy article.  Postoperative complications can be classified aetiologically or chronologically. Early complications staple line leakage clinical pres...
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Selective internal radiation therapy

Selective internal radiation therapy (SIRT), also know as hepatic radioembolisation, is a relatively new and developing modality for treating non-resectable liver tumours. The procedure consists of a transcatheter injection of radioactive particles via the hepatic artery.  It is generally consi...
Article

Normal mesenteric lymph nodes

In the pre-multidetector CT era, mesenteric lymph nodes were only really appreciated when enlarged. Following the advent of routine volume acquisition CT (and especially coronal reformats) they are commonly seen in normal individuals, which has raised the obvious question of what counts as mesen...
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Hepatobiliary contrast agents and LI-RADS

LI-RADS (Liver Imaging Reporting and Data System) is both a set of standardised terminology and a classification system for imaging findings in liver lesions. The LI-RADS score for a liver lesion is an indication of its relative risk for hepatocellular carcinoma (HCC). The classification system ...
Article

Left atrial enlargement

Left atrial enlargement may result from many conditions, either congenital or acquired. It has some characteristic findings on a frontal chest radiograph. CT or MRI may also be used for diagnosis. Clinical presentation An enlarged left atrium can have many clinical implications, such as: Ortn...
Article

Hyperechoic liver lesions

A hyperechoic liver lesion on ultrasound can arise from a number of entities, both benign and malignant. A benign hepatic haemangioma is the most common entity encountered, but in patients with atypical findings or a risk for malignancy, other entities must be considered. Benign hepatic haeman...
Article

Magnetic resonance neurography

Magnetic resonance neurography (MRN) is a relatively new non-invasive imaging technique for dedicated assessment of peripheral nerves. It is used to assess peripheral nerve entrapments and impingements as well as localization and grading of nerve injuries and lesions. Dedicated high-resolution...
Article

Fleischner Society pulmonary nodule recommendations

The Fleischner Society pulmonary nodule recommendations are for the follow-up and management of pulmonary nodules detected incidentally on imaging. The guideline does not apply to patients <35 years or with a history of cancer or immunosuppression. The initial guideline was released in 2005 1; s...
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Diffuse pulmonary nodules on HRCT (an approach)

A number of differentials must be kept in mind while approaching diffuse pulmonary nodules. Interpretation is easier if nodules are the only abnormality. These differentials can be narrowed down based on the several criteria: Based on appearance  miliary nodules   miliary tuberculosis silic...
Article

Renal transplant ultrasound

The central approach of renal transplant ultrasound is to evaluate for possibly treatable surgical or medical complications arising in the transplanted kidney. Institutions vary in the exact schedule of renal transplant ultrasound assessment, but it is common to obtain an initial ultrasound 24-...
Article

Ventral cord syndrome

Ventral cord syndrome (also known as anterior cord syndrome) is one of the incomplete cord syndromes and affects the anterior parts of the cord resulting in a pattern of neurological dysfunction dominated by motor paralysis and loss of pain, temperature and autonomic function. Anterior spinal ar...
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Myelination pattern on MRI

Myelination of the brain during infancy progresses in an orderly and predictable fashion which can be assessed with MRI.  At term (40 weeks corrected gestation) only certain structures are myelinated: dorsal brainstem ventrolateral thalamus lentiform nuclei central corticospinal tracts pos...
Article

Aortic nipple

An aortic nipple is seen in about 10% of PA chest x-rays on the lateral surface of the aortic arch/aortic knob. It represents the left superior intercostal vein. When prominent, superior vena cava obstruction should be considered as the left superior intercostal vein serves as a collateral path...
Article

CHALICE rule

The Children’s Head injury ALgorithm for prediction of Clinically Important Events (CHALICE) clinical decision rule was developed to predict clinically important brain injuries in children with head trauma. This rule identifies high-risk criteria and divides them into history, examination and me...
Article

Epistaxis

Epistaxis (plural: epistaxes) is the medical term for a nosebleed, and is very common in clinical practice with a broad differential diagnosis. Anterior epistaxes mainly bleed from Kiesselbach's plexus and posterior epistaxes (5% of all epistaxis) from Woodruff's plexus. Epidemiology Epistaxis...
Article

Polydactyly

Polydactyly (less commonly called hyperdactyly) refers to the situation where there are more than the usual number of digits (five) in a hand or foot. It can be broadly classified as: pre-axial polydactyly: extra digit(s) towards the thumb/hallux (radially) post-axial polydactyly: extra digit(...
Article

Pneumothorax

Pneumothorax refers to the presence of gas (air) in the pleural space. When this collection of gas is constantly enlarging with resulting compression of mediastinal structures, it can be life-threatening and is known as a tension pneumothorax. For those pneumothoraces occurring in neonates see t...
Article

Pituitary MRI (an approach)

A systematic approach to the pituitary region is crucial as small lesions can have a profound impact on the patient, and can be subtle even on high quality dedicated MRI imaging. Successful assessment of the pituitary region relies not only on a clear understanding of the local anatomy but also ...
Article

Focus‐assessed transthoracic echocardiography

FATE (focus‐assessed transthoracic echocardiography) is a goal-directed protocol used in critical care for indications such as haemodynamic instability, shock, and pulseless electrical activity (PEA) arrest 1. The protocol is designed as a series of questions as follows: does the left ventricl...
Article

Pelvic radiograph (an approach)

Systematic review Three rings trace the main pelvic ring and two obturator foramina if a ring is disrupted, think fracture... then look for a second one Joint spaces the sacroiliac joints should be symmetrical, joint space range 2-4 mm the symphysis pubis joint space should be ≤5 mm if ei...
Article

Cerebral oedema (summary)

This is a basic article for medical students and other non-radiologists Cerebral oedema describes the collection of additional fluid within the white matter of the brain. It is the brain's response to an insult and may take one of two broad forms: vasogenic (white matter) and cytotoxic (grey an...
Article

Subpleural reticulation

Subpleural reticulation is a type of reticular interstitial pattern where the changes are typically in a peripheral subpleural distribution (i.e. adjacent to costal pleural surfaces, located ≤1 cm from the pleura according to some publications 4). Pathology It can arise in a number of patholog...
Article

Fluid-fluid levels in bone tumours

Fluid-fluid levels in bone tumours is a commonly encountered finding, both in benign as well as malignant bone tumours, and can be used to differentiate between the two. Method of assessment On the sagittal T2W image: measure the length of the largest fluid-fluid level (A) measure the maximu...
Article

Umbilical venous flow assessment

Umbilical venous flow in the physiological situation comprises of a monophasic non-pulsatile flow pattern in the umbilical vein with a mean velocity of 10-15 cm/s. The presence of pulsatility implies a pathological state unless in the following situations: early in pregnancy: up to ~13 weeks ge...
Article

Coronary Artery Disease - Reporting and Data System - SCCT/ACR/NASCI (2016)

Coronary Artery Disease - Reporting and Data System (CAD-RADSTM) classification is proposed by the Society for Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR), and the North American Society for Cardiovascular Imaging (NASCI), last updated in 2016. This recomm...
Article

Cardiac segmentation model

The American Heart Association (AHA) has published the nomenclature and segmentation of the left ventricular myocardium (the cardiac segmentation model), now widely used for the description of disease-affected myocardial territories and wall function. There are 17 segments that have a reasonabl...
Article

Ankle impingement syndromes

There are several ankle impingement syndromes. They are characterised by limited range of motion and pain on attempting specific movements about the joint and often in a load-bearing position. They have variable aetiology and pathogenesis. They are best classified according to location. The key...
Article

Pulmonary nodule

Pulmonary nodules are small, rounded opacities within the pulmonary interstitium. Pulmonary nodules are common and, as the spatial resolution of CT scanners has increased, detection of smaller and smaller nodules has occurred, which are more often an incidental finding. Classification Pulmonar...
Article

Computed tomography texture analysis

Computed tomography texture analysis (or CTTA) is a new useful biomarker that provides an objective and quantitative assessment of tumour heterogeneity by analysing the differences in the pixel values of an image. Parameters assessed  gray-level frequency distribution: pixel intensity histogra...
Article

Pneumothorax in the exam

Getting a film with a pneumothorax in the exam is one of the many exam set-pieces that can be prepared for.   It is unlikely that they will give you a simple pneumothorax - so, it is worth while considering the likely causes and whether it is under tension. Miss it at your peril (both in real l...
Article

Urethrography

Urethrography refers to the radiographic study of the urethra using iodinated contrast media and is generally carried out in males.  Terminology When the urethra is studied with instillation of contrast into the distal/anterior urethra it has been referred to as retrograde urethrography (RUG)...
Article

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 ...
Article

Adult elbow radiograph (an approach)

Systematic review Whenever you look at an adult elbow x-ray, review: alignment fat pads bone cortex Alignment Check the anterior humeral line: drawn down the anterior surface of the humerus should intersect the middle 1/3 of the capitellum if it doesn't, think distal humeral fracture C...
Article

Situs inversus

Situs inversus, short form of the Latin “situs inversus viscerum”, is a term used to describe the inverted position of chest and abdominal organs. It is called situs inversus totalis when there is a total transposition of abdominal and thoracic viscera (mirror image of internal organs normal pos...
Article

Intervertebral disc disease nomenclature

Intervertebral disc disease nomenclature has changed over the years, and a familiarity with current definitions is essential if clear communication is to be achieved via radiology reports or referrals, especially as lumbar disc disease is a common problem and a source of a great deal of imaging....
Article

IOTA ultrasound rules for ovarian masses

The International Ovarian Tumour Analysis (IOTA) group ultrasound rules for ovarian masses are a simple set of ultrasound findings that classify ovarian masses into benign, malignant or inconclusive masses. These rules apply to masses that are not a classical ovarian mass (e.g. corpus luteum, en...
Article

Coronal balance

Coronal balance is one of the features that needs to be assessed on long spine radiographs obtained for spinal deformity, particularly scoliosis. It measures whether or not the upper spine is located over the midline (normal) or off to one side.  To assess coronal balance, a vertical (plumb) li...
Article

Sagittal balance (C7 plumb line)

Sagittal balance forms part of the plain radiographic assessment of spinal deformity including kyphotic or lordotic deformities and scoliosis. There are numerous ways of assessing this, using various bony landmarks and angles to evaluate whether or not a normal distribution of weight and stresse...
Article

Tumours of the base of skull (differential diagnosis)

Tumours of the base of skull are histologically varied and are often challenging to preoperatively diagnose and treat. Exactly which tumours are considered to be tumours of the base of skull is debatable. The broadest definition would include any tumour that involves or abuts the base of skull,...
Article

Knee radiograph (an approach)

Systematic review Effusion? Check for an effusion on the lateral: peripatellar fat pads should sit next to each other anterior suprapatellar fat pad prefemoral fat pad soft tissue density between them indicates an effusion if simple effusion (haemarthrosis), think severe ligamentous, meni...
Article

Second trimester ultrasound scan

The second trimester scan is a routine ultrasound examination in many countries that is primarily used to assess fetal anatomy and detect the presence of any fetal anomalies.  The second trimester extends from 13 weeks and 0 days to 27 weeks and 6 days of gestation although the majority of thes...
Article

Rapid ultrasound in shock

The rapid ultrasound in shock (RUSH) protocol is a structured point-of-care ultrasound (POCUS) examination performed at the time of presentation of a shocked patient. It is a more detailed and longer exam than the FAST scan, with the aim to differentiate between hypovolemic, cardiogenic, obstruc...
Article

Right paratracheal stripe

The right paratracheal stripe is a normal finding on the frontal chest x-ray and represents the right tracheal wall, adjacent pleural surfaces and any mediastinal fat between them. It is visible because of the silhouette sign created by air within the trachea medially and air within the lung lat...
Article

Review areas on chest x-ray

Review areas on a chest x-ray are common areas for missed findings, and special attention should be paid to them: lung apices: masses (e.g. Pancoast tumour), pneumothorax behind the heart: consolidation, masses, hiatus hernia below the diaphragm: free gas, lines and tubes (e.g. nasogastric tu...
Article

Systematic chest radiograph assessment (approach)

One approach to a systematic chest radiograph assessment is as follows: projection assessment of the technical adequacy tubes and lines cardiomediastinal contours hila airways, lungs and pleura bones and soft tissue review areas Following a systematic approach on every chest radiograph ...
Article

Assessment of chest x-ray technical adequacy (approach)

Described below are some points on an approach to the assessment of the chest x-ray technical adequacy. Rarely, a technically inadequate chest x-ray will prohibit diagnostic interpretation but knowledge of the limitations will impact on diagnostic confidence.  Inspiratory effort anterior aspec...
Article

Assessment of lungs, pleura and airways on chest x-ray (approach)

Described below is one approach to the assessment of airways, lungs and pleura on chest x-ray. Start by assessing the tracheal air column, followed by the lungs and finally the pleural spaces.  Tracheobronchial tree assess position, should be central and deviation can be due to positive mass ...
Article

Forbidden areas in mammography

In breast imaging, forbidden, check or review areas are zones that, according to Tabár, require special attention in mammographic interpretation. These are: on a mediolateral oblique (MLO) view the "milky way" (retromammary fat): a 3-4 cm wide band parallel to the edge of the pectoral muscle ...
Article

Assessment of cardiomediastinal contours on chest x-ray (approach)

Described below is one approach to systematic assessment and associated pathology of the cardiomediastinal contours on chest x-ray. Mediastinum size: widened mediastinum can be seen in aortic dissection, traumatic aortic injuries abnormal contour, e.g. lymphadenopathy, anterior mediastinal m...
Article

Assessment of pulmonary hila on chest x-ray (approach)

Described here are points to consider when approaching the assessment of the pulmonary hila on chest x-ray: shape normally appear as gentle C-shapes on either side contents: pulmonary arteries and veins, bronchi, lymph nodes position left hilum is normally 1-2 cm higher than the right low ...
Article

Transverse view of abdomen

A transverse abdominal view is one of the standard views on fetal echocardiography and is very useful for assessing situs abnormalities. In case of situs solitus (normal situs), the stomach is on the left and liver on the right. The descending aorta lies anterior and to the left of the spine whi...
Article

Assessment of bones and soft tissue on chest x-ray

Described below are points to consider on assessment of bones and soft tissue on chest x-ray.  ribs rib fractures lesions (most commonly metastases): may appear as lucent and/or sclerotic; inverting contrast may help in identification previous surgery, e.g. thoracotomy with rib resection ve...
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

Brock model for pulmonary nodules

The Brock model, also known as the PanCan model, is a multivariable model that estimates the risk that a pulmonary nodule on CT scan is a lung cancer. The model was developed from participants enrolled in the Pan-Canadian Early Detection of Lung Cancer Study 1, has been validated in lung cancer...
Article

Solitary pulmonary nodule (an approach)

A solitary pulmonary nodule, according to the Nomenclature Committee of the Fleischner Society, is defined as a rounded opacity, well or poorly-defined on a conventional radiograph, measuring up to 3 cm in diameter and is not associated with lymphadenopathy, atelectasis, or pneumonia. Several r...
Article

Incidental lung nodules

Incidental lung nodules are encountered commonly in normal clinical practice on CT. The risk of developing cancer in very small nodules (<5 mm) is very low. However, clear-cut recommendations are still not in place with high variation in practice amongst reporting radiologists 1. As a result, it...
Article

Sigmoid volvulus versus caecal volvulus

The following points may be helpful to distinguish between sigmoid volvulus and caecal volvulus on plain film. Sigmoid volvulus arises in the pelvis (left lower quadrant) extends towards the right upper quadrant ahaustral in appearance sigmoid volvulus causes obstruction of the proximal lar...
Article

Pelvic ultrasound

Pelvic ultrasound is usually the initial modality for imaging gynaecologic pathology, including acute pelvic pain and chronic pelvic pain. The exam normally involves two components: a transabdominal (TA) evaluation and a transvaginal (TV) / endovaginal (EV) evaluation. Normal ultrasound anatomy...
Article

Oesophageal intubation

Oesophageal intubation refers to the incorrect placement of an endotracheal tube in the oesophagus. Within minutes its consequences can be catastrophic with the seriousness of its outcome depending largely on the timeliness of its diagnosis. Epidemiology Accidental oesophageal intubation can h...
Article

Bedside lung ultrasound in emergency (approach)

Bedside lung ultrasound in emergency (BLUE) is a basic point-of-care ultrasound (POCUS) examination performed for undifferentiated respiratory failure at the bedside, immediately after the physical examination, and before echocardiography. It has been designed as a fast (<3 minute), three-point...
Article

Ultrasound of the wrist

Ultrasound is a useful imaging modality for evaluation of the wrist, allowing high-resolution imaging of anatomy while simultaneously allowing dynamic evaluation of the joint, tendons, and ligaments. Approach There are multiple possible approaches to imaging the wrist with ultrasound. The exam...
Article

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 calvaria. It is a wider setting than the standard non-contrast window, and there are a num...
Article

Isomerism

Isomerism is a term which in general means 'mirror-image'. It is used in the context of heterotaxy and is of two types: left isomerism right isomerism Left isomerism Mirror image of the structures on the left side of the chest along the left-right axis of the body, i.e. patients with isomeri...
Article

Scrotal scintigraphy

Scrotal scintigraphy is a radio-isotope examination of the scrotal contents, primarily in patients presenting with scrotal pain. Indications Although, ultrasound remains the mainstay of scrotal imaging, scintigraphy can be used where the diagnosis is unclear, since ultrasound appearances for s...
Article

Caudate–right lobe ratio

Caudate-right lobe ratio (C/RL) is used in the assessment of livers, usually in the setting of cirrhosis, in which there is atrophy of the right lobe with hypertrophy of the caudate lobe.  Method for measuring image: axial slice immediately below the bifurcation of the main portal vein line 1...
Article

Uteroplacental blood flow assessment

Uteroplacental blood flow assessment is an important part of fetal well-being assessment and evaluates Doppler flow in the uterine arteries and rarely the ovarian arteries. Pathology In a non-gravid state and at the very start of pregnancy the flow in the uterine artery is of high pulsatility ...
Article

Sonographic features of malignant lymph nodes

Lymphadenopathy is quite common, and it can be very difficult to differentiate malignant lymphadenopathy from reactive nodal enlargement. Several gray scale and colour Doppler features favour malignancy in a lymph node. Gray scale parameters that favour malignancy size: larger-more likely mal...
Article

Cardiac CT

Computed tomography of the heart or cardiac CT is routinely performed to gain knowledge about cardiac or coronary anatomy, to detect or diagnose coronary artery disease (CAD), to evaluate patency of coronary artery bypass grafts or implanted coronary stents or to evaluate volumetry and cardiac f...
Article

RANO criteria for glioblastoma

Response assessment in neuro-oncology criteria (RANO), published in 2010 1, are used to assess response to first-line treatment of glioblastoma (as well as lower grade astrocytoma 3) and have largely superseded the older Macdonald criteria (which only dealt with glioblastoma multiforme) 2. For ...
Article

Cardiothoracic ratio

The cardiothoracic ratio (CTR) aids in the detection of enlargement of the cardiac silhouette, which is most commonly from cardiomegaly but can be due to other processes such as a pericardial effusion.  Terminology Some report CTR as a percentage, however this is incorrect, as it is a ratio. ...
Article

Ultrasound guided breast biopsy

Ultrasound guided percutaneous breast biopsy is a widely used technique for an accurate histopathological assessment of suspected breast pathology. It is a fast, safe and economical procedure. Indications Ultrasound guidance is limited to lesions visible on ultrasound study, such as:  BIRADS ...
Article

Cardiac silhouette

Cardiac silhouette refers to the outline of the heart as seen on frontal and lateral chest radiographs and forms part of the cardiomediastinal contour. The size and shape of the cardiac silhouette provide useful clues for underlying disease. Radiographic features From the frontal projection, t...
Article

Chest radiograph assessment using ABCDEFGHI

ABCDEFGHI can be used to guide a systematic interpretation of chest x-rays. Assessment of quality / Airway The quality of the image can be assessed using the mnemonic PIER: position: is this a supine AP file? PA? Lateral? inspiration: count the posterior ribs. You should see 10 to 11 ribs wi...
Article

Chest x-ray: circulation (summary)

This is a basic article for medical students and other non-radiologists Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review where C refers to circulation ...
Article

Congenital heart disease chest x-ray (an approach)

With the advent of echocardiography, and cardiac CT and MRI, the role of chest x-rays in evaluating congenital heart disease has been largely been relegated to one of historical and academic interest, although they continue to crop up in radiology exams. In most instances a definite diagnosis ca...
Article

Traumatic aortic injury in the exam

Getting a film with traumatic aortic injury in the exam is one of the many exam set-pieces that can be prepared for.  This is one of the cases you should look and not speak for 10 seconds as there tends to be a lot of findings on the film of patients with a traumatic aortic injury. Description...
Article

Unilateral hypertranslucent hemithorax

Unilateral hypertranslucent hemithorax has many potential causes. It may be the result of rotation away from an optimal position or because of pathology. Rotation A unilateral hypertranslucent hemithorax may be caused by the positioning of the patient. Rotation away from the radiation beam alt...
Article

Pathognomonic

The term pathognomonic in radiology, as well as clinical medicine in general, refers to a finding or a sign that is only found in a single specific condition or specific group of conditions, i.e. the finding has 100% specificity. Thus by implication, a pathognomonic finding cannot and does not h...
Article

CT cystography

CT cystography is a variation of the traditional fluoroscopic cystogram. Instead of anterograde opacification of the urinary collecting system (as with CT urography), contrast is instilled retrograde into the patient's bladder, and then the pelvis is imaged with CT. Indications suspected bladd...
Article

Intercaudate distance to inner table width ratio

Intercaudate distance to inner table width ratio (CC/IT) is used in assessing patients with neurodegenerative diseases that affect the caudate nuclei. It is best known for assessing individuals with suspected Huntington disease but is in no way specific for the diagnosis, also seen in other less...
Article

Frontal horn width to intercaudate distance ratio

Frontal horn width to intercaudate distance ratio (FH/CC) is used in assessing patients with suspected Huntington disease.  On the same axial plane obtained on the ACPC (anterior commissure and posterior commissure) line, the ratio between the distance between the caudate heads (where they are ...
Article

Antenatal features of Down syndrome

Antenatal screening of Down syndrome (and other less common aneuploidies) should be available as a routine component of antenatal care. It allows families to either adjust to the idea of having a child with the condition or to consider termination of pregnancy. For a general description of Down...
Article

Geographic appearance

Geographic appearance is a term used in imaging, and other clinical fields (e.g. histopathology) to describe lesions with a well-circumscribed margins with adjacent tissues.  The term derives from the somewhat similar appearance of the outline of countries on a map or the clear demarcation forme...
Article

Lung cancer (staging - IASLC 8th edition)

The IASLC (International Association for the Study of Lung Cancer) 8th edition lung cancer staging system was introduced in 2016 and supersedes the IASLC 7th edition.  TNM system T: primary tumour Tx: primary tumour cannot be assessed or tumour proven by the presence of malignant cells in spu...
Article

Anatomic position

The anatomic position, also referred to as the standard anatomic position, is the consistent position of the human body in which positional reference is made for anatomical nomenclature. It is not reliant on whether the patient is standing, supine, prone, sitting, etc. The position is defined a...
Article

Imaging of gunshot injuries

Gunshot injuries often require imaging assessment, and this evaluation has both clinical relevance (assessment of organ damage, surgical planning and prognostication), and often also forensic implications. Epidemiology Incidence of gunshot injuries to the head is increasing in some countries, ...

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