Articles

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496 results found
Article

Musculoskeletal imaging (dual-energy CT)

Dual-energy CT has a number of clinical applications in the assessment of the musculoskeletal system particularly in the realm of artefact reduction and material composition. Detection of bone marrow edema Similar to the concept of using virtual non-contrast imaging, virtual non-calcium images...
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Normal gastrointestinal tract imaging examples

This article lists examples of normal imaging of the gastrointestinal tract and surrounding structures, divided by modality. Plain radiograph abdominal film example 1 example 2: erect and supine example 3: pediatric example 4: pediatric example 5: young adult male Barium studies barium ...
Article

Whole-body CT (protocol)

CT polytrauma/multitrauma, also called trauma CT, whole body CT (WBCT) or panscan, is an increasingly used investigation in patients with multiple injuries sustained after significant trauma. The majority of the evidence regarding whole-body CT is, understandably, retrospective. There is some e...
Article

Noise power spectrum

The noise power spectrum (NPS), also known as the power spectral density, of a signal, is the Fourier transform of the noise autocorrelation. It gives the intensity of noise as a function of spatial frequency. It is used in all the main radiological modalities, most commonly x-ray-based, i.e. ra...
Article

Epidermal inclusion cyst

Epidermal inclusion cysts or epidermal cysts are common cutaneous lesions that represent proliferation of squamous epithelium within a confined space in the dermis or subdermis. Terminology These are occasionally termed sebaceous cysts, although this is a misnomer as the lesion does not origin...
Article

Cervical spine (AP view)

The anteroposterior (AP) cervical spine projection is part of the cervical spine series. Indications This projection helps to visualize pathology relating to C3-C7 in the anatomical position, demonstrating any compression fractures, clay-shoveler fractures and herniated nucleus pulposus (HNP) ...
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Hand (bilateral PA view)

The bilateral PA view is merely a single film that includes both hands, side by side. Although convenient, research in 2023 showed that the distortion due to divergent rays when imaging bilaterally can impact diagnosis and x-raying the hands individually is preferred at a minimal dose increase 1...
Article

Air gap technique (general radiography)

The utilization of the air gap technique in general radiography is limited due to the need for equipment facilitation to create the air gap when it is not inherent in the standard technique. Horizontal-beam lateral hip There are many different methods of performing the horizontal beam lateral ...
Article

Normal genitourinary tract imaging examples

This article lists examples of normal imaging of the genitourinary tract and surrounding structures, divided by modality. Kidneys Plain radiograph KUB: example abdominal x-ray: example Intravenous Urogram / Pyelogram (IVU/IVP) IVU: example 1, example 2 Ultrasound renal ultrasound: exampl...
Article

Digital breast tomosynthesis

Digital breast tomosynthesis (DBT) is an imaging technique that allows a volumetric reconstruction of the whole breast from a finite number of low-dose two-dimensional projections obtained by different X-ray tube angles, with a geometric principle very similar to that applied in stratigraphic te...
Article

Pelvis radiograph (pediatric)

The radiography of the pelvis in the pediatric patient varies greatly from the adult examination; particularly as specialized techniques are often required to immobilize the patient. To avoid future mobility and pain complications, it is essential to treat fractures and correct developmental pat...
Article

Practical radiography: A Hand-Book of the Applications of the X-Rays

The book Practical radiography: A Hand-Book of the Applications of the X-Rays was the first ever textbook on x-rays anywhere in the world. It was written by H Snowden Ward and first published in May 1896 by Dawbarn & Ward. This is a mere six months after Wilhelm Roentgen's discovery of x-rays. ...
Article

Orbitomeatal line

The orbitomeatal line, also known as the canthomeatal line, was the traditional axial plane used for CT of the brain. It was easily identified on the inspection of the patient's head when tilting the gantry or patient's head to achieve a standard axial plane.  The orbitomeatal line was defined ...
Article

Normal lower limb imaging examples

This page lists examples of normal imaging of the lower limb, divided by region and modality. Pelvic girdle plain radiograph pelvis example 1: frontal example 2: pediatric example 3: pediatric (9 months, 11 months, and older child) example 4: trauma supine example 5: frontal (female) ex...
Article

Normal hepatobiliary imaging examples

This article lists examples of normal imaging of the liver and biliary tree and surrounding structures, divided by region and modality. Liver Plain radiographs liver silhouette: example Ultrasound liver ultrasound example 1 with shear wave elastography liver Doppler ultrasound: example ne...
Article

Pediatric scaphoid (axial view)

The scaphoid axial view in pediatrics examines the scaphoid bone in its true anatomical position. Since minimizing radiation dose is essential in pediatric imaging, one posteroanterior angled view of the scaphoid is usually sufficient. The scaphoid bone begins ossification at age 5 years and com...
Article

F-18 DOPA

F-18 DOPA (3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine) is a PET radiotracer primarily used in the evaluation of neuropsychiatric diseases, movement disorders, and brain malignancies 1.  Production L-DOPA is the non-proteinogenic amino acid precursor to dopamine, with F-18 DOPA usually being s...
Article

Lipoma

Lipomas are benign tumors composed of mature adipocytes. They are the most common soft tissue tumor, seen in ~2% of the population.  Epidemiology Patients typically present in adulthood (5th-7th decades). Associations In some cases, multiple lipomas are associated with syndromes and other di...
Article

Pleomorphic adenoma of the salivary glands

Pleomorphic adenomas of the salivary glands, also known as benign mixed tumors (see below), are the most common salivary gland tumors. The salivary glands are the most common site of pleomorphic adenomas. On imaging, they commonly present as well-circumscribed rounded masses, most commonly loca...
Article

Chest (lateral view)

The lateral chest view examines the lungs, bony thoracic cavity, mediastinum, and great vessels. Indications This orthogonal view to a frontal chest radiograph may be performed as an adjunct in cases where there is diagnostic uncertainty. The lateral chest view can be particularly useful in as...

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