Comparison and Evaluation of PET/CT Image Registration

Area of Science:

• Medical Imaging
• Radiology
• Nuclear Medicine

Background:

• Accurate image registration combining functional (PET) and anatomical (CT) data is vital for improved diagnosis, treatment planning, and prognosis.
• Quality assurance of PET/CT systems is essential for reliable clinical and research applications.

Purpose of the Study:

• To assess the spatial accuracy, reliability, and speed of registration techniques on the GeminiTM PET/CT Imaging System.
• To establish a quality assurance program for PET/CT registration in clinical and research settings.

Main Methods:

• Utilized a multi-layer alignment bearing source device and a Rando a Man phantom to validate intrinsic PET/CT alignment.
• Simulated misalignments using known transformations and assessed two semi-automated registration techniques.
• Quantitatively compared registration accuracy by measuring distances between fiducial marker centroids.

Main Results:

• Fused PET/CT imaging proved superior to individual visual correlation for identifying registration errors.
• The GeminiTM PET/CT system demonstrated robust intrinsic alignment and accurate image registration with user interaction.
• Maximum spatial error was below 4 mm, exceeding the PET scanner's spatial resolution.

Conclusions:

• The PET/CT hybrid system offers reliable intrinsic alignment and accurate registration, suitable for most clinical and research applications.
• Semi-automated registration techniques provide quantitative assessment of spatial accuracy.
• The validated registration methods contribute to the quality assurance of PET/CT imaging.