Fluoroscopy Flashcards

Question

What is the concept and process behind indirect conversion FPDs?

Answer 1

INDIRECT - scintillator such as CsI absorbs x-rays and convert it into light photons. - the light photons are detected by an array of photodiodes or amorphous silicon thin-film transistors (TFT) placed behind the scintillator - these are then converted into electrical signals - these electrical signals are converted to digital images on a monitor

Answer 2

- eliminates the need for a scintillator and instead uses a layer of amorphous selenium for the detector material - when x-rays interact with the selenium, they generate electron-hole pairs creating an electrical charge - electrical charge collected by TFT integrated onto the surface of the selenium - collected electrical charge signals are processed and converted into a digital image

Answer 3

Direct - convert x-ray electrons directly into images - advantages: high spatial resolution, effective for low energy x-rays (e.g. mammography) indirect - convert x-rays to visible light, then to electrons for image formation - advantages: faster, more cost-effective, and efficient - disadvantages: requires higher radiation doses and provides lower resolution. - commonly used in TFT fluoroscopy/angiography and CCD for general radiology

Answer 4

- definition: pulse width refers to the duration of time that radiation is emitted during fluoroscopy - impact: correct selection of examination parameters and choice of exam protocol, including pulse width, directly affects radiation exposure to both patients and staff - achieving the right balance in pulse width is crucial to ensure clear and accurate imaging while minimising unnecessary radiation exposure

Answer 5

= persistence of the image on the screen following x-ray exposure - this can degrade image quality, leading to blurriness and obscuring fine details - lag can result in delayed visualisation of moving structures, complicating the assessment of dynamic processes

Answer 6

- refers to duration required to collect x-ray data and generate a complete image during real-time procedures impact on image quality - longer integration times: collect more x-ray data, resulting in smoother, clearer images. However, this may increase the radiation dose to the patient. - short integration times: capture less data, which can lead to grainy images, While this reduces radiation exposure, it may compromise image quality. - balancing quality and dose: finding the right balance between integration time and radiation dose is crucial for optimising image quality while minimising exposure.

Answer 7

- A recursive filtering technique enhances image quality by adjusting based on data from previous images, resulting in a smoother and clearer final picture. - This method leverages perceptual integration, allowing the brain to combine multiple image frames for improved clarity and detail. - By utilising recursive filters, fluoroscopy systems can effectively reduce noise and artefacts, leading to better diagnostic outcomes.

Answer 8

- digital enhancement: take advantage of post-processing tools available in modern fluoroscopy systems to enhance image quality digitally - edge enhancement: use edge enhancement algorithms to sharpen the borders of structures, improving their visibility.

Answer 9

- Over-Couch Systems: X-ray tube is positioned above patient, which can help reduce radiation scatter to healthcare professionals but may increase exposure to the patient. - Under-Couch Systems: The X-ray tube is located beneath the patient, allowing for more direct imaging of certain areas while potentially increasing scatter radiation exposure to the healthcare team. - Safety must be considered, x-ray tube positioning is crucial to minimise radiation exposure to both patients and healthcare professionals.

Answer 10

patient exposure is INDIRECT - with the x-ray tube positioned beneath the patient table, the primary beam passes through the patient before reaching the detector. This indirect path results in a more diffuse and less concentrated radiation dose. staff exposure is REDUCED SCATTERED RADIATION - although healthcare professionals are still exposed to scattered radiation, the under-couch positioning helps reduce their exposure. The patient's body and the table act as partial shields, decreasing the intensity of scattered radiation that reaches staff members.

Answer 11

patient exposure is DIRECT - the x-ray tube is positioned above the patient, directing the primary x-ray beam downward. This can lead to higher radiation doses to the patient as the beam is more concentrated. staff exposure is INCREASED SCATTERED RADIATION - healthcare professionals may experience greater exposure to scattered radiation due to the X-ray tube's overhead position. Without the shielding effect of the patient's body, more scattered radiation can reach staff members in the room, necessitating the use of protective measures.

Answer 12

Enhancing the visibility of specific anatomical structures and organs. This aids in diagnosing conditions such as vascular abnormalities, GI disorders, and urinary tract issues, facilitating more accurate assessments and treatment planning. Omnipaque, gastrografin, urografin.

Answer 13

Angiography - vascular imaging: iodinated contrast is essential in fluoroscopic angiography for visualising blood vessels, aiding in diagnosis of vascular diseases, aneurysms, blockages. - interventional procedures: nephrostomies, stent placements, embolisation GI imaging - barium replacement: iodinated contrast is preferred when barium is contraindicated, such as in cases of suspected perforation or aspiration. Urinary tract imaging - urography: to visualise the urinary system, helping to identify structures, blockages and tumours. Dynamic studies - Real time imaging: iodinated contrast enables dynamic studies, such as video fluoroscopy examinations, facilitating assessments with speech and language therapists (SALT).

Answer 14

- a radiopaque contrast medium used in fluoroscopy and other x-ray imaging procedures. It is a white, chalky powder that is mixed with water to form a thick, radio-opaque suspension. - not soluble in water - so ideal contrast agent for imaging the GI tract, including the oesophagus, stomach and intestines. - well tolerated by patients

Answer 15

Aspiration into lungs - pneumonia: aspiration of barium sulfate can lead to pneumonitis, causing cough, shortness of breath and chest pain. Rare but serious complication. - airway blockage: barium can obstruct small airways, resulting in breathing difficulties and reduced oxygenation. Treatment - immediate medical attention is essential for barium aspiration. Treatment may include physiotherapy, oxygen therapy, and in severe cases, bronchoscopy to remove the barium.

Answer 16

Entry into body cavities - perforation: if barium sulfate enters a perforated organ or cavity, it can lead to serious complications such as peritonitis (inflammation of the abdominal cavity), infection and sepsis. - blockage: barium sulfate may cause gastrointestinal blockages or obstructions Treatment - immediate medical intervention is essential if barium enters body cavities unintentionally. Treatment options may include flushing the affected area, surgical removal or other appropriate measures.

Answer 17

- Carbex - preparation that patients take which expands the stomach and enables clearer diagnostic images to be produced. - active ingredients: sodium bicarbonate, simeticone, citric acid. And an adequate volume of gas which is non-interference with barium coating. - absence of bubbles, rapid disintegration leaving no residue, ease of swallowing and low cost.

Fluoroscopy Flashcards

(41 cards)