Take 6: More Deets on the C-Arm

The C-Arm offers a variety of control panel options, all of the which the tech should be familiar with. Depending on the type of C-Arm unit, the control panel may be on an (un)attached remote control, on the mobile unit itself, or perhaps on the monitor cart and may consist of five categories: orientation, collimation, contrast, generator and workstation (ASRT, 2010). Check out the list below for a brief description of each of the operation modes!

Magnification mode: This mode allows the image to be magnified at any time

Pulse Mode: This mode reduces dose by creating an x-ray beam that pulsates at times increments resulting in a significant reduction of patient dose.

Digital Spot Mode (Snapshot): This activates a digital spot resulting in an improved computer- enhanced image as compared with a half fluoro image.

Auto/ Manual Exposure Control: This simply means that exposure can be made manually by the operator or automatically by the use of an AEC.

Subtraction: This is a technique in which an initial image is recorded during continuous fluoroscopy, and this image is then used as a filter for each of the following images meaning that the C-Arm will subtract the initial image form all the other images produced. This technique is sometimes used for operative cholangiography.

Road-Mapping: Similarly to subtraction, this control will remove stationary structures from images; however, the difference is that a specific fluoro-image is held on the screen in combination with continuous fluoro.

Foot Pedal: This allows for hands- free operation of the C-Arm. Some physicians prefer to be in control of the unit and exposure being made so this nifty gadget allows for them to have the control. Gotta be careful not to let them get carried away with the fluoro though!

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Take 4: Components of Fluoroscopy

The fluoroscope unit is similar to that of a general x-ray unit; however there is one key difference-- it's flipped flopped. On a regular x-ray unit, the tube is positioned above the patient table and the image receptor is underneath the patient. On the other hand, the fluoro x-ray tube is located underneath the patient table and the image receptor above. Here is a simple description of each of the components of the fluoroscopy unit: 1. Generator : This is important for converting the alternating current (AC) to direct current (DC) which then allows for the adjustment of mAs and kVp as well as to select pulsed fluoroscopy (ASRT, 2010). 2. X-Ray Tube : This is contained within a glass or metal tube to help prevent leakage and scatter radiation. DC will flow from cathode to anode; and once the electrons reach the anode, x-rays are produced. 3. Collimator: Blades that allow for modification of shape/size of x-ray field, reduction of scatter radiation thus resulting

Take 7: Image Intensifier vs Flat Panel Detector

As mentioned before in "Take 4," the Image Intensifier (II) and Flat Panel Detector (FPD) are important fluoroscopic components that function similarly yet are different. Since we know that the purpose of each component is to brighten the image without increasing dose, here is a brief comparison of the difference of both the II and FPD. Here is what's different about the II: Consists of input phosphor, photocathode, electrostatic focusing lenses, anode, output phosphor, and glass envelope Input phosphor: absorb and convert x-rays to light photons Photocathode: absorbs the light created by input phosphor and then emits photo(light)electrons Electrostatic focusing lenses: guides and directs photoelectrons to output phosphor Anode : these photoelectrons then pass through the anode Output Phosphor: converts the photoelectrons that exited the anode to light photons Here is what's different about the FPD: "All flat panel detectors used in radiol

Take 9: Dose Limits & Exposure Patterns

For the protection and safety of radiation workers ands staff, it is very important to limit the amount of dose as much as possible. It is our responsibility as radiation workers to keep radiation exposure ALARA- As Low As Reasonably Achievable! In addition to the three keys (time, distance, and shielding) of radiation safety and protection, there are other ways to manage dose. For example, the number of image taken and repeated. During fluoroscopy, setting the number of frames per second is one way the radiologist can limit patient dose. The more frames (or pictures) taken per second, the more radiation being exposed to the patient and surrounding people (ASRT, 2010). In order to effectively protect workers and patients, dose limits have been established. Check out the table below!... sorry for the poor quality screenshot. Note: Dose equivalent is measured in Sieverts and/ or rems. (1 rem= .01 Sv) Statkiewicz-Sherer, Mary Alice, Paula J. Visconti, E. Russell Ritenour, an

Zoe's "Take" on Fluoroscopy

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