PET and CT Image Quality and Artifacts

A series of vocabulary flashcards designed to help understand key terms and concepts related to PET and CT Image Quality and Artifacts.

PET Image Quality

The overall visual and diagnostic clarity of images produced in Positron Emission Tomography (PET).

Image Quality (IQ) Factors

Factors that influence the quality of PET images, including patient preparation, technologist skills, and hardware/software performance.

Normal Distribution of FDG

Refers to the expected uptake patterns of Fludeoxyglucose (FDG) in various organs during PET imaging, used in oncology.

Patient Preparation

Activities and conditions required prior to a PET scan to ensure optimal image quality, including diet and medication.

SUV Parameters

Standardized Uptake Values, which are critical in assessing the metabolic activity of tissues in PET images.

Radiopharmaceuticals

Radioactive compounds used in PET imaging to visualize physiological processes.

Detectors

Devices in PET scanners that capture gamma rays emitted from radiopharmaceuticals and convert them into images.

Gantry Offsets

The positioning adjustments between the PET and CT scanners that can affect image registration and quality.

Motion Artifacts

Blurring or distortion in PET images caused by patient movement during the scan.

Beam Hardening

An artifact in CT images due to the absorption of lower energy x-ray photons by denser tissues.

Partial Volume Effects

Artifacts occurring when voxel sizes are too thick relative to the anatomical structures being visualized, causing blurriness.

Hydration's Role in IQ

Adequate fluid intake helps improve image quality by improving FDG distribution.

Chemotherapy Effects on Imaging

Chemotherapy can alter the distribution of FDG, impacting image interpretation.

FDG Excretion

The process by which FDG is eliminated from the body, primarily through the urinary tract.

Uptake Phase

The initial period following a radiopharmaceutical injection, during which the agent localizes in tissues.

CT Artifacts

Image distortions in CT scans caused by equipment issues, patient movement, or anatomical challenges.

Cold Uptake Room

A low-temperature environment that may cause unexpected fat uptake artifacts in PET imaging.

Artifacts due to Infiltrated Dose

Anomalies in PET imaging caused by the improper administration of radiopharmaceuticals.

Anxious Patient Effects

Anxiety can lead to physiological responses that may impact image quality during PET scans.

Electronics Quality Check (QC)

Daily checks performed on PET systems to ensure they perform optimally before patients are scanned.

Reconstruction Techniques

Methods used to process raw PET data into meaningful images; different methods vary in effectiveness.

Timing of Injection

The synchronization of radiopharmaceutical injection with patient positioning that can affect image quality.

Contrast Medium

Substances used in imaging studies to enhance visibility of internal structures, which can introduce their own artifacts if not managed correctly.

Radiative Shadows

Streak artifacts created by high-density materials such as metals during image reconstruction.

PSF Modeling

Point Spread Function modeling in reconstruction processes that describes how a point source's signal is spread.

Adaptive Filters

Algorithms used in imaging to correct artifacts by enhancing image clarity and minimizing noise.

System Maintenance

Regular servicing of imaging equipment to prevent and correct artifacts and ensure image quality.

Abnormal Glucose Metabolism

A key indicator in oncology studies, where altered FDG patterns signify potential malignancies.