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319 results found

Tangential views

Tangential views are useful to differentiate intracutaneous radiopaque particles in a tattoo from intraparenchymal microcalcifications. Mammographic findings close to the skin such as masses, microcalcifications, skin dimpling or shaded areas always pose a problem of differential diagnosis. Va...

Tardus parvus

Tardus parvus refers to a pattern of Doppler ultrasound spectral waveform resulting from arterial stenosis. The phenomenon is observed downstream to the site of stenosis, and is due to reduced magnitude of blood flow through the narrowed vessel during ventricular systole 7. This characteristic ...

Tc-99m sestamibi

Tc-99m sestamibi is one of the technetium radiopharmaceuticals. Characteristics photon energy: 140 KeV physical half life: 6 hours normal distribution: thyroid, parathyroid, heart excretion: hepatobiliary target organ: colon, kidneys, bladder, gallbladder Uses, doses and timings parathy...

Temporomandibular joint (axiolateral view)

The axiolateral temporomandibular view allows for visualization of the articular tubercle, mandibular condyle and fossa and is thus useful to identify structural changes and displaced fractures, as well as assess excursion and joint spaces. Clinical indications include trauma, the presence of ...

The air gap technique

The air gap technique is a radiographic technique that improves image contrast resolution through reducing the amount of scattered radiation that reaches the image detector. In select situations, this technique can be used instead of an anti-scatter grid as the primary scatter reduction method i...

Thermoluminescent dosimeter

Thermoluminescent dosimeter (TLD) is a passive radiation detection device that is used for personal dose monitoring or to measure patient dose. Parts plastic holder nickel-coated aluminum card with TLD discs the discs are made of a thermoluminescent material, commonly calcium sulphate doped...

Thoracic spine (AP view)

The thoracic spine AP view images the thoracic spine, which consists of twelve vertebrae. It is utilized in many imaging contexts including trauma, postoperatively, and for chronic conditions. Patient position the patient is erect or supine, depending on clinical history ideally, spinal imag...

Thoracic spine (lateral view)

The thoracic spine lateral view images the thoracic spine, which consists of twelve vertebrae. It is utilized in many imaging contexts including trauma, postoperatively, and for chronic conditions. It is used in conjunction with the thoracic spine AP view to complete a thoracic spine series. P...

Thoracic spine series

The thoracic spine series is comprised of two standard projections along with a range of additional projections depending on clinical indications. The series is often utilized in the context of trauma, postoperative imaging and for chronic conditions. Radiographs of the thoracic spine are consi...

Thumb (AP/PA view)

The thumb AP (anteroposterior) view is one of the standard views for assessment of the thumb. The PA (posteroanterior) view can be utilized when the patient is unable to achieve the position required for the AP view. They are one part of the three view thumb series. There will be some magnific...

Thumb (lateral view)

The thumb lateral view is an orthogonal projection of AP/PA view and helps in the localisation of a foreign body in the thenar eminence, as well as providing valuable information of suspected dislocations. Patient position patient is seated alongside the table the forearm is placed on table ...

Thumb (oblique view)

The thumb oblique view is a part of the thumb series and is particularly useful in cases with traumatic indications. Patient position patient is seated alongside the table forearm is placed on table the wrist is kept in ulnar deviation and thumb abducted fingers are kept in contact with the...

Thumb series

The thumb series is comprised of a posteroanterior and oblique, projection. The posteroanterior projection is interchangeably performed anterioposter or posteroanterior depending on mobility. It examines in detail the first metacarpal and its articulations. Thumbs have a vital impact in our day ...

Tibia fibula (AP view)

The tibia fibula AP view is part of a two view series of the entire tibia, fibula, and both the knee and ankle joint. Patient position the patient may be supine or sitting upright with their leg straighten on the table the foot is in dorsiflexion the toes will be pointing directly toward th...

Tibia fibula (lateral view)

The tibia fibula lateral view is part of a two view series of the entire tibia, fibula, and both the knee and ankle joint. Patient position the patient is in a lateral recumbent position on the table the lateral aspect of the knee and ankle joint should be in contact with the table resulting...

Tibia/fibula series

The tibia/fibula is comprised of an anteroposterior (AP), and lateral radiograph. The series is often used in emergency departments to evaluate the entirety of the tibia and fibula after trauma. Indications The tibia/fibula radiographs are performed for a variety of indications including: tr...

Toes (AP view)

Toes AP view is part of a three view toe series and includes the phalanges and the toe(s) of interest and the distal half of the associated metacarpals. Patient position the patient can be either supine or be sitting upright on the table knee should be flexed so the plantar surface of the foo...

Toes (oblique view)

The toes medial oblique view is part of the toe series examining the phalange and metatarsals of the foot. Patient position the patient may be supine or upright depending on comfort the affected leg must be flexed enough that the plantar aspect of the foot is resting on the image receptor th...

Toes series

The toes series is comprised of an AP, AP oblique, and a lateral projection. The series is often utilized in trauma situations. It examines the entirety of the proximal middle and distal phalanges of the foot. Indications Toe radiographs are performed for a variety of indications including 1:...

Toes (sesamoid view)

The sesamoid view of the toes is a specialed view examing the sesamoid bones of the first metatarsal. Patient position the patient may be supine or sitting upright with their leg straighten on the table the foot is in dorsiflexion the toes pulled back toward the patient Technical factors ...

Tracheal bifurcation angle

The tracheal bifurcation angle can have a wide range of normal values in patients and can vary significantly in serial radiographs. It is of poor diagnostic value due to the lack of sensitivity and specificity in identifying the underlying pathology. Terminology The interbronchial angle is th...

Triple-rule-out CT

Triple-rule-out CT (TRO CT) angiography may be ordered in the setting of acute chest pain to examine the thoracic aorta and the coronary and pulmonary arteries. The protocol helps exclude life-threatening causes of acute chest pain, especially if atypical, or if alternative causes to acute coron...

Tucked CC views

In the standard CC views posterior tissue may be excluded from the field of view, due to the anatomical attachment to the chest wall restricting mobility of breast tissues. The tucks CC views are useful to depict lesions deep in the posterior portion of the breast, located between 10 and 2 o'clo...

Upper limb radiography

Upper limb radiography is the radiological investigation of the shoulder girdle, humerus, ulna, radius, carpals and metacarpals of the hand. It is often utilized in the context of trauma to rule out fractures and dislocations.

V/Q scan

V/Q (ventilation/perfusion) scan is a scintigraphic examination of the lung that evaluates pulmonary vasculature perfusion and segmental bronchoalveolar tree ventilation. Indications diagnosis of suspected pulmonary embolism (PE) monitor pulmonary function following lung transplant provide p...

Windowing (CT)

Windowing, also known as grey-level mapping, contrast stretching, histogram modification or contrast enhancement is the process in which the CT image greyscale component of an image is manipulated via the CT numbers; doing this will change the appearance of the picture to highlight particular st...

Wrist (carpal bridge view)

The carpal bridge view an additional view to the three view series of the wrist and carpal bones. It is used to assess the dorsal aspect of the scaphoid, lunate and the triquetrum. Patient position the patient is seated alongside the table dorsal aspect of affected wrist is placed on the dete...

Wrist (carpal tunnel view)

The carpal tunnel view is an axial projection to demonstrate the medial and lateral prominences and the concavity. It can be utilized to investigate potential hook of hamate, pisiform and trapezium factures. Patient position patient stands with the back facing the table palmar surface of hand...

Wrist (clenched fist view)

The clenched fist view is an additional projection used to evaluate suspected widening of the scapholunate interval, often performed bilaterally it is a functional view that requires the patient to clench both hands. Patient position patient is seated in front of the table both hands are pl...

Wrist (horizontal beam lateral view)

The horizontal beam lateral wrist view is a modified lateral projection when performing the three view series of the wrist and carpal bones in trauma. It is the orthogonal projection of the PA wrist without any patient movement, making it the most appropriate projection for patients in pain. Pa...

Wrist (lateral view)

The lateral wrist view is part of a three view series of the wrist and carpal bones. It is the orthogonal projection of the PA wrist. Patient position patient is seated alongside the table the affected arm if possible is flexed at 90° so the arm and wrist can rest on the table abduct the hum...

Wrist (oblique view)

The oblique wrist view is part of a three view series of the wrist and carpal bones. It is not generally performed in follow-up studies unless specifically requested. Patient position patient is seated alongside the table the affected arm if possible is flexed at 90° so the arm and wrist can ...

Wrist (PA view)

The PA wrist view is part of a three view series of the wrist and carpal bones. Although performed PA the view can often be referred to an AP view. Patient position patient is seated alongside the table the affected arm if possible is flexed at 90° so the arm and wrist can rest on the table ...

Wrist (radial deviation view)

The wrist PA radial deviation view is specialized projection employed to better demonstrate the carpal bones that lay on the ulnar aspect of the wrist. Patient position patient is seated alongside the table the affected arm if possible is flexed at 90° so the arm and wrist can rest on the tab...

Wrist radiograph

Wrist radiographs are ubiquitous in the emergency departments. They are commonly performed in the pediatric and elderly populations after a fall on an outstretched hand as well as in patients after higher force trauma. Moreover, they may be performed as part of a skeletal survey looking for meta...

Wrist series

The wrist series is comprised of a posteroanterior, oblique, and lateral projection. The series examines the carpal bones that are consisting of the scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate and hamate. It also examines the radiocarpal and distal radiocarpal joint al...

XCCL view

An XCCL view is a supplementary mammographic view. It is a type of exaggerated cranio-caudal view. It is particularly good for imaging the lateral aspect of the breast. It is often done when a lesion is suspected on a MLO view but cannot be seen on the CC view. In this view, the lateral aspect...

XCCM view

An XCCM view is a supplementary mammographic view. It is a type of exaggerated cranio-caudal view. It is particularly good for imaging the medial portion of the breast. In this view, the medial portion of the breast is placed forward. A negative 15° tube tilt is suggested. An optimal XCCM view ...

Xenon-127

Xenon-127 is a radiopharmaceutical principally used when a performing VQ scan. It is not a widely used alternative to xenon-133 with the main advantage being a higher proton energy allowing for post perfusion scanning. photon energy: 203 KeV physical half life: 36.3 days

X-ray artifacts

Artifacts can present in a variety of ways including abnormal shadow noted on a radiograph or degraded image quality and have been produced by artificial means from hardware failure, operator error and software (post-processing) artifacts. There are common and distinct artifacts for film, comp...

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