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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.

472 results found
Article

Mesenteric lymph nodes

In the premultidetector CT era, mesenteric lymph nodes (often shortened to mesenteric nodes) were only really appreciated when enlarged. Following the advent of routine volume acquisition CT (and especially coronal reformats) lymph nodes in the mesentery are commonly seen in normal individuals, ...
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Microvascular decompression

Microvascular decompression is a surgical procedure for cranial nerve compression syndrome, most often carried out for trigeminal neuralgia, or less frequently hemifacial spasm and glossopharyngeal neuralgia. It is usually carried out via a retrosigmoid craniotomy. The culprit blood vessel, eit...
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Midfoot equinus

Midfoot equinus is an abnormality in foot alignment where there is abnormal plantarflexion of the foot in the midfoot. Related pathology Midfoot equinus occurs as a component of congenital talipes equinovarus.
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Mid zone

The mid (or middle) zone is one of the four chest radiograph zones.  Radiographic appearance Plain radiograph on frontal chest radiographs, extends between the superior and inferior aspects of the hilum
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Mitral annular plane systolic excursion

Mitral annular plane systolic excursion (MAPSE) refers to the displacement of the mitral valvular plane in the z-direction and reflects left ventricular longitudinal contraction or shortening, which has been attributed to account for about 60% of the stroke volume 1. Terminology Mitral annular...
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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...
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Monoarticular arthropathy

Monoarticular arthropathy can result from a number of causes: Commonest 2: gout (15-27%) septic arthritis (8-27%) osteoarthritis (5-17%) rheumatoid arthritis (RA) (11-16%) Less common 2: traumatic arthritis HADD (hydroxyapatite deposition disease) reactive arthritis 2 avascular necrosi...
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MR enterography

MR enterography (MRE) is a non-invasive technique for the diagnosis of small bowel disorders. Note: This article is intended to outline some general principles of protocol design. The specifics will vary depending on MRI hardware and software, radiologist's and referrer's preference, institutio...
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MRI of the ankle (an approach)

MRI of the ankle is one of the more frequent examinations faced in daily radiological practice. This approach is an example of how to create a radiological report of an MRI of the ankle with coverage of the most common anatomical sites of possible pathology, within the ankle without claim for co...
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MRI of the brachial plexus

MRI of the brachial plexus is used to provide a causal diagnosis for brachial plexopathies. It provides clear structural analysis of the brachial plexus, its intraneural integrity, as well as surrounding structures 1,3. Related pathology brachial plexus injuries grading of brachial plexus inj...
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MRI of the elbow (an approach)

MRI of the elbow is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an elbow MRI with coverage of the most common anatomical sites of possible patho...
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MRI of the shoulder (an approach)

MRI of the shoulder is one of the more frequent examinations faced in daily radiological practice. This approach is an example of how to create a radiological report of an MRI shoulder with coverage of the most common anatomical sites of possible pathology, within the shoulder. Systematic revie...
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MRI of the wrist (an approach)

MRI of the wrist is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an MRI of the wrist knee with coverage of the most common anatomical sites of po...
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MRI targeted prostate biopsy

MRI targeted prostate biopsy refers to an imaging targeted technique rather than the traditional systematic approach of a prostate biopsy after respective imaging with multiparametric MRI (mpMRI) of the prostate. As a consequence of the recent advances of multiparametric MRI (mpMRI) of the pros...
Article

Mulder sign

Mulder sign is a clinical test used to examine causes of metatarsalgia associated with Morton neuroma. It has high specificity (100%) but relatively low sensitivity (62%) 2. See the ultrasound correlate described separately: sonographic Mulder sign. Technique With one hand, clasp the metatarsa...
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Multiphase CT angiography in acute ischemic stroke

Multiphase CT angiography is an evolving imaging technique in acute ischemic 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 leptomeninge...
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Myocardial area at risk

Myocardial area at risk (AAR) is defined by the ischemic proportion of the myocardium after coronary occlusion and reflects the potential size of the myocardial infarction 1-9. Usage The assessment of myocardial area at risk is an important measure in the evaluation of the potentially salvagea...
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Myocardial mapping

Myocardial mapping or parametric mapping of the heart is one of various magnetic resonance imaging techniques, which has evolved and been increasingly used in the last decade for non-invasive tissue characterization of the myocardium 1-5. Unlike normal T1-, T2- or T2*- images, parametric mapping...
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Myocardial salvage

Myocardial salvage is referred to as the reversibly injured myocardium in a setting of myocardial ischemia and/or myocardial infarction, which remains non-infarcted after reperfusion 1-7. Usage The assessment of myocardial salvage is an important measure in the evaluation of the efficacy of th...
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 organisms. as set down by the International Commision on Zoological Nomenclature (ICZN) 1. As per the standard binomial system, the genus and species of the org...
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Nasogastric tube positioning

Assessment of nasogastric (NG) tube positioning is a key competency of all doctors as unidentified malpositioning may have dire consequences, including death.  Evaluation of Nasogastric tube Plain radiograph A correctly placed nasogastric tube should 10: descend in the midline, following the...
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Nasogastric tube position on chest x-ray (summary)

This is a basic article for medical students and other non-radiologists   Nasogastric (NG) tube position on chest x-ray should be assessed following initial placement and on subsequent radiographs. Reference article This is a summary article; we have a more in-depth reference article NGT. S...
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Neonatal chest radiograph in the exam setting

The neonatal chest radiograph in the exam setting may strike fear into the heart of many radiology registrars, but it need not! There are only a limited number of diagnoses that will be presented on such films and they are often highlighted by the history. Gestation First of all, have a look ...
Article

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...
Article

Neurodegenerative MRI brain (an approach)

Imaging of the brain in patients with suspected neurodegenerative conditions is common and challenging, as in patients with subtle and equivocal signs and symptoms, the imaging findings are also often subtle and equivocal. In many instances, by the time imaging findings are clear cut, then the p...
Article

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 require all of the following: alert and stable no focal neurologic de...
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Nipple markers

Nipple markers can be a useful technique in the evaluation of small radiodensities overlying the expected position of the nipple on a chest radiograph. Not uncommonly a small round opacity projects over the lower thorax on a chest radiograph (see: solitary pulmonary nodule). Often, especially i...
Article

Normal pulmonary venous Doppler

Normal pulmonary venous blood flow in the pulmonary veins may be investigated during echocardiography with spectral Doppler analysis. Perturbations in the normal pulmonary venous waveform may indicate the presence of diastolic dysfunction and elevated filling pressures in the left atrium and ven...
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Normal radiographic measurements of the shoulder

Normal radiographic measurements of the shoulder are important in evaluation of the osseous relationships in plain film radiography. Normal measurements do not rule out pathology, and must be considered in the context of other findings and the clinical presentation. AC joint space: 5-8 mm (narr...
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Occam's razor

Occam's razor (also known as lex parsimoniae), an often cited principle of parsimony, economy, or succinctness used in problem-solving. It has also been expressed as the KISS principle or "Keep it simple stupid!". It states that among competing hypotheses, the one with the fewest assumptions sh...
Article

Esophageal intubation

Esophageal intubation refers to the incorrect placement of an endotracheal tube in the esophagus. Within minutes its consequences can be catastrophic with the seriousness of its outcome depending largely on the timeliness of its diagnosis. Epidemiology Accidental esophageal intubation can happ...
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On-track and off-track shoulder lesions

Bipolar shoulder lesions of anterior glenohumeral dislocations (i.e. combined bony Bankart and Hill-Sachs lesions) put patients at increased risk of Hill-Sachs engagement or recurrent instability. Determining if the Hill-Sachs lesions are on-track or off-track can help guide management, although...
Article

Optic nerve sheath diameter

Optic nerve sheath diameter has significance in the assessment of papilledema in cases of elevated intracranial pressure. Pathology The optic nerve sheath demonstrates changes in diameter with CSF pressure changes as there is a layer of subarachnoid space between the nerve and its sheath, whic...
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Osteolytic lesions with septations and trabeculations (differential)

Differential diagnosis of lytic bone lesions with septations and trabeculations include 1: benign lesions unicameral bone cyst aneurysmal bone cyst giant cell tumor non-ossifying fibroma intraosseous lipoma fibrous dysplasia Brown tumor ameloblastoma adamantinoma haemophilic pseudotum...
Article

Ottawa ankle rules

The Ottawa ankle rules are a clinical decision-making strategy for determining which patients require radiographic imaging for ankle and midfoot injuries. Proper application has high (97.5%) sensitivity and reduces the need for radiographs by ~35% 1,2,4.  There are two components, assessing for...
Article

Ottawa knee rules

The Ottawa knee rules are a clinical decision-making strategy for determining which patients require radiographic imaging for knee pain. A patient with knee pain qualifies for knee radiographs if any of the following apply: 55 years or older point tenderness at the fibular head isolated poin...
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Ovarian-Adnexal Reporting and Data System Magnetic Resonance Imaging (O-RADS MRI)

The Ovarian-Adnexal Reporting and Data System Magnetic Resonance Imaging (O-RADS MRI) forms the MRI component of the Ovarian-Adnexal Reporting and Data System (O-RADS). This system aims to ensure that there are uniform unambiguous sonographic and MRI evaluations of ovarian or other adnexal lesio...
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Ovarian-Adnexal Reporting and Data System (O-RADS)

The Ovarian-Adnexal Imaging Reporting and Data System, (O-RADS), aims to ensure that there are uniform unambiguous sonographic and MRI evaluations of ovarian or other adnexal lesions, accurately assigning each lesion to a risk category of malignancy being present, which informs the appropriate m...
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Pediatric elbow radiograph (an approach)

Pediatric elbow radiographs are commonly encountered in the emergency department and, when approached in a systematic fashion, are not as difficult to interpret as most people think! Systematic review Ossification Check that the ossification centers are present and in the correct position. Th...
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Pediatric urinary tract infection (NICE guideline)

The British National Institute for Health and Care Excellence (NICE) published the “Urinary tract infection in under 16s: diagnosis and management” in 2007 as a guideline for pediatric urinary tract infection (UTI) management, including imaging, prophylaxis and follow-up 1.  This article intend...
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Pain rating scales

There are a number of pain rating scales used by clinicians and researchers to gauge the severity of patients' pain. Commonly used methods: pain numeric rating scale (NRS/NPRS) visual analog scale (VAS) verbal rating scale (VRS) faces pain scale-revised (FPS-R) Pain numeric rating scale Th...
Article

Pancreatic ultrasound

Pancreatic ultrasound can be used to assess for pancreatic malignancy, pancreatitis and its complications, as well as for other pancreatic pathology. Preparation Fast the patient to reduce interference from overlying bowel gas, which may otherwise make visualization difficult. Scanning techni...
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Paragonimiasis

Paragonimiasis is a disease caused by several species of the trematode genus Paragonimus.  More than 50 different species of Paragonimus have been described in Asia, Africa, and the Americas and of those nine species infecting humans. The most important species is Paragonimus Westermani, which ...
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

Pathology checklists

Pathology checklists are series of sometimes missed pathological entities possible to see on radiological studies. They are helpful when reporting a radiograph, ultrasound, or cross-sectional examination as a way to ensure that you fully review a film and don't fall foul of satisfaction of searc...
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Patterns of sinonasal obstruction

Recognizing patterns of sinonasal obstruction is useful to help localize 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...
Article

PECARN traumatic brain injury algorithm

The PECARN (Pediatric Emergency Care Applied Research Network) traumatic brain injury algorithm is a clinical decision rule that aims to identify children at very low risk of clinically important traumatic brain injury (ci-TBI) 1. This validated pediatric algorithm predicts likelihood of the abo...
Article

Pelvic pain in the exam

It is important to have a systematic way of approaching a case with pelvic pain in the exam.  Most examinations are performed using ultrasound. 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. Only...
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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...
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Pelvic radiograph (checklist)

The pelvic radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Plain radiograph ...
Article

Pelvic ultrasound

Pelvic ultrasound is usually the initial modality for imaging gynecologic 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

Perigestational hemorrhage in the exam

Getting a film with pregestational hemorrhage in the exam is one of the many exam set-pieces that can be prepared for.  Description Transabdominal and transvaginal (TV) pelvic ultrasound shows an anteverted uterus with an intrauterine gestational sac. MSD is 20 mm in TV study with a single, li...
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Peritoneal thickening

Peritoneal thickening is a descriptive term given to describe any form of thickening of the peritoneum.  It can occur with both benign and malignant peritoneal disease. It can be classified into various subtypes based on its morphology: smooth peritoneal thickening peritonitis peritoneal car...
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Per vaginal bleeding in the exam

It is important to have a systematic way of approaching a case with per vaginal (PV) bleeding in the exam.  Premenopausal embedded IUCD lost IUCD submucosal fibroid Pregnancy-related perigestational hemorrhage intrauterine fetal demise ectopic pregnancy ruptured ectopic cervical ectopi...
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Physiological pelvic intraperitoneal fluid

Physiological pelvic intraperitoneal fluid refers to the presence of a small volume of free fluid in the pelvis, particularly the pouch of Douglas. It occurs in young females of reproductive age and can be a mimic of traumatic free fluid in abdominal trauma. Unfortunately, pelvic free fluid may...
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Pineal region (an approach)

A systematic approach to the pineal region is crucial as it is at the confluence of many intracranial structures/regions and is the site of origin of a number of unique pathologies as well as playing host to many entities which are more frequently encountered elsewhere. As such an understanding ...
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 ...
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Placental abruption in the exam

Getting a film with placental abruption (premature separation of placenta from uterus) in the exam is one of the many exam set-pieces that can be prepared for.  Description Transabdominal and transvaginal pelvic ultrasound show a single live fetus with gestational age of 27 weeks. The cervix i...
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Pleural effusion volume (ultrasound)

Measurement of a pleural effusion volume with point-of-care ultrasonography may be a useful tool for intensivists and is an active area of research in critical care 7. In controlled settings ultrasound may detect constitutive pleural fluid, can reliably detect effusions >20 mL in clinical setti...
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Pneumothorax

Pneumothorax, sometimes abbreviated to PTX, (plural: pneumothoraces) refers to the presence of gas (often 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 pneu...
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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 worthwhile considering the likely causes and whether it is under tension. Miss it at your peril (both in real li...
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Point-of-care ultrasound (curriculum)

The point-of-care ultrasound (PoCUS) curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core applications of ultrasonography in a point-of-care setting. Point-of-care ultrasound refers to ultrasonography which may be simultaneously performed,...
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Polycystic ovarian syndrome in the exam

Getting a film with polycystic ovarian syndrome in a subfertile patient is one of the many exam set-pieces that can be prepared for.  Description Transabdominal and transvaginal pelvic ultrasound show an anteverted uterus with a normal size. There is diffuse thickening of the endometrium to 17...
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: preaxial polydactyly: extra digit(s) towards the thumb/hallux (radially) postaxial polydactyly: extra digit(s)...
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Prostate MRI (an approach)

Prostate MRI has become an increasingly frequent examination faced in daily radiological practice and is mainly conducted for the detection, active surveillance and staging of prostate cancer. This approach is an example of how to create a radiological report of a prostate MRI with consideration...
Article

Prosthetic cardiac valves on chest x-ray (an approach)

Prosthetic cardiac valves are a routine finding on chest X-ray. The frequency and degree of exposure is greatest in larger hospitals with cardiothoracic centers; however, prosthetic valves are commonplace universally. Recognition of which valve has been replaced, any other related cardiothoraci...
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Pudendal nerve block (technique)

Pudendal nerve blocks are performed on those with suspected or proven pudendal neuralgia.  Using CT will ensure accurate needle placement, which aims for a perineural pudendal nerve injection in the pudendal canal, also known as Alcock's canal.  Indications pudendal neuralgia diagnostic Cont...
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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...
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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 inves...
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Radiographic evaluation of anterior cruciate ligament reconstruction

Radiographic evaluation of anterior cruciate ligament (ACL) reconstruction involves: femoral component a line is drawn along the posterior cortex of the femur a second line is drawn along the roof of the intercondylar notch of the femur (Blumensaat line) the point of intersection of these tw...
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Radiographic positioning terminology

Radiographic positioning terminology is used routinely to describe the position of the patient for taking various radiographs. Standard nomenclature is employed with respect to the anatomic position. Terminology Basic terms of relations anterior is towards the front of the body (Latin: before...
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Radiological image artifact

Most artifacts in radiology refer to something seen on an image that are not present in reality but appear due to a quirk of the modality itself. Artifact is also used to describe findings that are due to things outside the patient that may obscure or distort the image, e.g. clothing, external c...
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Radiology training in the Republic of Ireland

Radiology training in the Republic of Ireland is organized under the auspices of the Faculty of Radiologists at the Royal College of Surgeons in Ireland. The duration of training is 5 years leading to a Certificate of Completion of Specialist Training which is a requirement for entry to the Spec...
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Radiotracers for SPECT brain imaging

Radiotracers for SPECT brain imaging are divided into two classes: diffusible and not-diffusible radiotracers; this distinction lies in the ability (or not) to cross the blood-brain barrier (BBB). The not-diffusible radiotracers - composed of ions or polar molecules - are unable to cross the li...
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

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

Ravitch procedure

The Ravitch procedure is one of the corrective surgical treatments for pectus excavatum and pectus carinatum. The costal cartilage is removed and the sternum detached before inserting a small bar underneath the sternum to hold it in the desired position. The bar is left implanted until the carti...
Article

Reactive vs malignant lymph nodes (ultrasound features)

A number of sonographic features are helpful in distinguishing reactive versus malignant lymph nodes. Grey scale features Features that favor reactive/infective nodes over malignancy include: nodal matting surrounding soft tissue edema Doppler features Doppler examination is particularly u...
Article

Red and yellow flags for guiding imaging of lower back pain

Lower back pain (also known as lumbago) is very common and often referred for imaging, with the vast majority of cases due to benign self-limiting causes which don't require imaging and resolve with conservative measures. Numerous authors have described various methods for supporting appropriate...
Article

Renal artery stenosis

Renal artery stenosis (RAS) (plural: stenoses) refers to a narrowing of a renal artery. When the process occurs slowly, it leads to secondary hypertension. Acute renal artery stenosis does not lead to hypersecretion of renin. Pathology When the stenosis occurs slowly, collateral vessels form a...
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

Reporting and Data Systems (disambiguation)

In recent years there has been a proliferation of Reporting and Data Systems (RADS), which have been proposed - and in many cases widely adopted - as standardized systems for the reporting of imaging of various body organs, often, but certainly not always, with a focus on oncological disease 2. ...
Article

Reporting tips for aortic aneurysms

When issuing an MRI or CT report on a patient with an aortic aneurysm, whether it be thoracic or abdominal, a number of features should be mentioned to aid the referring clinician in managing the patient. Reporting tips for aortic aneurysms include 1,2: size and shape sac dimensions (outer sur...
Article

Retained barium in appendix

Retained barium in appendix refers to the presence of barium in appendix beyond 72 hours from the start of procedure. Proposed significance Previously used as a sign of appendicitis. Actual significance Retained barium outlining the appendiceal lumen allows evaluation of its width and contou...
Article

Reticular and linear pulmonary opacification

In chest radiology, reticular and linear opacification refers to a broad subgroup of pulmonary opacification caused by a decrease in the gas to soft tissue ratio due to a pathological process centered in or around the pulmonary interstitium. This includes thickening of any of the interstitial co...
Article

Retrosigmoid craniotomy

Retrosigmoid craniotomy also known as a suboccipital lateral craniotomy refers to the neurosurgical procedure in which lateral section of the occipital bone is removed to gain surgical access to the wide range of neoplastic and vascular pathologies in the cerebellopontine angle.
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

Retrotracheal space

The retrotracheal space (or Raider triangle) is a radiolucent mediastinal space best seen on lateral chest x-rays. It is normally triangular in shape but can vary greatly in size and shape depending on the patient's body habitus and lung volume 1. Boundaries anterior: posterior tracheal stripe...
Article

Reversal of umbilical arterial end diastolic flow

Reversal of umbilical artery end-diastolic flow (REDF) or velocity is often an ominous finding if detected after 16 weeks. It is classified as Class III in severity in abnormal umbilical arterial Dopplers 6. Epidemiology The estimated incidence is at ~0.5% of all pregnancies with a much higher...
Article

Reverse total shoulder arthroplasty

A reverse total shoulder arthroplasty (RTSA) (also known as a reverse total shoulder replacement (RTSR)) is a variant on the standard total shoulder replacement (TSR). It is often the preferred method when there has been advanced damage to the rotator cuff as seen in rotator cuff arthropathy. P...
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 tumor), pneumothorax pulmonary hilum: mass, lymphadenopathy, vessel enlargement behind the heart: consolidation, masses, hiatus hernia below th...
Article

Revised PIOPED criteria for diagnosis of pulmonary embolus

The revised PIOPED criteria for the diagnosis of pulmonary embolus indicate the probability of pulmonary emboli based on findings on V/Q scan (ventilation-perfusion scintigraphy). The following article reflects the revised interpretation criteria promulgated in 1993 1 based on retrospective anal...
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...

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