Items tagged “reference needed”
70 results found
Extraocular muscle involvement in thyroid associated orbitopathy (mnemonic)
A mnemonic to remember the order in which extraocular muscles are involved in thyroid-associated orbitopathy (TAO) is: I'M SLOw Mnemonic I: inferior rectus M: medial rectus S: superior rectus L: lateral rectus O: obliques muscles (superior oblique and inferior oblique) There is some deba...
Nodular filling defects of duodenum (differential)
Nodular filling defects due to mucosal lesions in the duodenum are due to a number of processes. For a differential list which includes non-mucosal lesions see duodenal filling defects. The differential diagnosis for mucosal lesions includes: heterotopic gastric mucosa 1-2 mm clustered onl...
The increased globe size or macrophthalmia may have many differentials: buphthalmos (congenital glaucoma) axial myopia macrophthalmus in neurofibromatosis type 1 (NF1) connective tissue disorders: Marfan syndrome, Ehlers-Danlos syndrome Focal enlargement: staphyloma coloboma See also mi...
Tc-99m DTPA (diethylene-triamine-pentaacetate) is one of the technetium radiopharmaceuticals used in renal imaging and primarily used to measure the glomerular filtration rate (GFR). Characteristics photon energy: 140 KeV physical half-life: 6 hours biological half-life: 2.5 hours normal di...
Normal 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, ...
Skeletal metastases (a.k.a. bone metastases) are common and result in significant morbidity in patients with metastatic disease. Although the diagnosis is often straightforward, especially as in many cases there is a well-documented history of metastatic malignancy, sometimes they may mimic beni...
The physics of MRI are complicated and much harder to understand than those underpinning image generation in plain radiography, CT or ultrasound. What follows is a very abbreviated, 'broad strokes' description of the process. Essentially, the process can be broken down into four parts: prepar...
Hybrid imaging refers to the fusion of two (or more) imaging modalities to form a new technique. By combining the innate advantages of the fused imaging technologies synergistically, usually a new and more powerful modality comes into being. Some hybrid imaging modalities are synergistic solely...
Space charge refers to the collection of electrons which are emitted from the metal surface, after the application of tube current, at a short distance away from the metal surface. These electrons collect and form a cloud of negative charge around the metal surface. This space charge repels and...
It is common to see jewelry artifacts on imaging examinations, most commonly plain radiographs, although also on other modalities, where they can produce unhelpful artifacts that may obscure important structures and preclude confident diagnostic evaluation 1. These include: body piercings in m...
Radiology training for chiropractic radiologists in the United States of America
Radiology training for chiropractic radiologists in the United States of America includes a minimum of 3 years of residency after obtaining a Doctor of Chiropractic degree (DC), which is largely focused on musculoskeletal (MSK) radiology. A small number of chiropractic radiologists pursue a one ...
Microbubbles are intravenous contrast agents used in contrast-enhanced ultrasound. Microbubble contrast agent is different to the agitated saline contrast agent often used in echocardiographic studies. Microbubbles consist of a gas surrounded by a lipid, lipopolymer, or polymer shell. They rang...
Cholecystectomies are one of the most common surgical procedures performed. Evidence of a cholecystectomy is often seen on imaging procedures with surgical clips in the gallbladder fossa and radiologists should be aware of possible complications. Indications cholelithiasis cholecystitis gal...
Aberrant right subclavian and left vertebral arteries
Published 11 Mar 2017
History of imaging of the pituitary region
The history of imaging of the pituitary region encompasses many different modalities and has greatly evolved over the years, including plain radiographs, pneumoencephalography, angiography, CT and MRI. The pituitary gland is situated in the central skull base, closely related to the sphenoid sin...
A tracheobronchial stent is a device used in the treatment of symptomatic airway compression. This device is inserted under bronchoscopic guidance in patients with external compression from mediastinal based malignancy, for example lung or esophageal cancers. It may also be used in the treatme...
Epoch (machine learning)
An epoch is a term used in machine learning and indicates the number of passes of the entire training dataset the machine learning algorithm has completed. Datasets are usually grouped into batches (especially when the amount of data is very large). Some people use the term iteration loosely and...
The Ionizing Radiation (Protection of Persons Undergoing Medical Examination or Treatment) Regulations 1988 were popularly known as the POPUMET regulations. They were the former legal regulations in the UK covering the protection of patients undergoing the use of ionizing radiation for diagnosti...
The fornix conjunctiva is loose soft tissue lying at the junction between the palpebral conjunctiva (covering the inner surface of the eyelid) and the bulbar conjunctiva (covering the globe). Each eye has two fornices, the superior and inferior fornices. The fornix permits freedom of movement of...
An anlage in biology refers to the primordial precursor of a tissue or organ, which is still recognisable as a collection of cells that will form that specific tissue. The term is commonly used in medicine to refer to organs, such as the pancreas, when one is describing anatomical variants and ...