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Searchterm 'Flow' found in 1 term [
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Regional Cerebral Blood Flow
(RCBF) The regional cerebral blood flow is the evaluation of blood circulation in individual brain sections.
Contrast Media Injector
Contrast media injectors are part of the medical equipment used to deliver fluids in examinations such as CT, MRI, fluoroscopy and angiography. Many of these diagnostic imaging procedures include the administration of intravenous contrast agents to enhance the blood and perfusion in tissues.

Mainly there are two types of injector technology:
Piston-based systems use a plunger/piston to move a piston in the cylinder of a reservoir, which works in two directions to first fill the reservoir and then deliver the fluid from the reservoir to the patient, similar to a hand-held syringe.
Peristaltic-pump-based systems operate as rotary pumps that use rollers to compress sections of flexible tubing, drawing fluid directly from the supply source and delivering it to the patient.

See also Single-Head Contrast Media Injector, Dual-Head CT Power Injector, Syringeless CT Power Injector.

The use of x-ray contrast agents in computed tomography (CT) began with a hand injection by the radiologist in the scan room. During its history, CT scanners have made great improvements in speed and image quality. Actual CT systems with multiple detectors allow scan times of a few seconds per body region. Some CT protocols require multiphase scans, where a body region is imaged with a single bolus of contrast in different blood flow phases. Automatic power (pressure) contrast media injectors are required to provide precise control of flow rate, volume and timing of injection. The use of a saline bolus following contrast administration reduces the volume of contrast required.

Most relevant topics for the use of a power injector in medical imaging procedures such as contrast enhanced computed tomography (CECT):
Avoidance of microbiologic contamination;
workflow efficiency in the use of the contrast media injector;
contrast cost and waste volume;
reimbursement.

Must have basic injector control options:
Flow rate with a usual range from 0.1 to 10 mL/sec in 0.1 mL/sec increments; some injectors can be set to inject in ml/min or ml/hour;
volume range from 1 mL to 200 mL for contrast and saline phases;
pressure limit typically programmable from 50 psi to 300 psi in 1 psi increments (also displayable in kPa and kg/cm²).

Examples of other injector control options:
Warmer/heater; an increase in temperature of the contrast medium results in a decrease in its viscosity; warmed contrast media are less viscous and offer lesser resistance;
pre-filled syringes; the compatibility with many selected syringes makes it easy to change and select the appropriate contrast medium for each patient;
injection reports accessible via RIS/PACS for dose management systems and records of prior injections.

Multiphase Bone Scintigraphy
A multiphase bone scintigraphy (bone scan) is a nuclear medical examination including blood flow images, immediate images, and delayed images.
The blood flow study is a dynamic sequence of planar images of the bone region of interest obtained during the injection of the radiopharmaceutical (radioactive tracer).
The immediate phase (blood pool or soft tissue study) include one or more static images of selected regions, obtained immediately after the blood flow phase within 10 min.
Delayed images (usually whole body) are usually acquired 2-5 hours after injection. Later (6-24 hour) delayed images result in a higher target to background ratio and may permit better evaluation of the pelvis if this was obscured by bladder activity on the routine images. This late imaging may be particularly helpful in patients with renal insufficiency or peripheral circulatory disorders and those with urinary retention.
Antegrade
Antegrade blood flow is the naturally direction of the flowing blood.
CT Power Injector
A computed tomography (CT) power injector (also named pressure injector) is used to deliver contrast agents during CT imaging procedures with high-flow, high-volume, fixed-rate injection at relatively high pressures. The use of power injectors allows precise administration of contrast agent to obtain consistent high quality CT images. A dual-head CT power injector permits loading of contrast and saline onto the same injector. Contrast injection systems manage injector protocol data, improve patient safety, and workflow efficiency. When combined with pressure monitoring systems and hardware to prevent extravasation (accidental leakage of IV material into the surrounding tissue) these CT injectors can simultaneously mitigate risk.

See also Contrast Media Injector, Single-Head CT Power Injector, Multi-Head Contrast Media Injector, Syringeless CT Power Injector.
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 [last update: 2023-11-06 02:01:00]