Performance evaluation of SPRINT, a single photon ring tomography for brain imaging

Area of Science:

• Medical Imaging
• Nuclear Medicine
• Biomedical Engineering

Background:

• High-resolution brain imaging is crucial for understanding neurological disorders.
• Existing single photon emission computed tomography (SPECT) systems have limitations in resolution and sampling speed.
• Development of advanced imaging devices is needed for improved diagnostic capabilities.

Purpose of the Study:

• To introduce and evaluate SPRINT, a prototype single photon tomograph designed for high-resolution human brain imaging.
• To assess the performance characteristics of the SPRINT system, including spatial resolution and sensitivity.
• To demonstrate the feasibility of using SPRINT for brain blood flow imaging with I-123 labeled compounds.

Main Methods:

• SPRINT utilizes a ring of stationary sodium iodide (NaI) detectors.
• Fan-beam sampling is achieved via a rotating eight-slit aperture ring, completing projections in 1/8 revolution.
• System performance was evaluated using phantoms and preliminary human studies with hydroxyiodopropyldiamine (HIPDM).

Main Results:

• SPRINT achieved in-plane and cross-plane resolutions of 8mm and 10mm FWHM, respectively.
• System sensitivity was measured at 1000 counts per second per microCurie/cc for Tc-99m in a 20 cm phantom with an 18% energy window.
• Preliminary human brain blood flow images using HIPDM were successfully obtained.

Conclusions:

• SPRINT demonstrates potential as a high-resolution brain imaging tool for I-123 labeled compounds.
• The system's design facilitates efficient data acquisition and provides detailed anatomical and functional information.
• Further studies are warranted to explore SPRINT's clinical applications in various neurological conditions.