Speaker
Description
The Walk-Through PET (WT-PET) is an innovative approach to Positron Emission Tomography imaging that rethinks both system geometry and patient workflow. Unlike conventional cylindrical PET scanners that require patients to lie still on a moving bed, the WT-PET uses two vertically aligned flat detector panels positioned on either side of a standing patient. This design introduces a more open and accessible scanning environment, allowing patients to walk into the system and position themselves without extensive assistance. The scanner dimensions—106 cm in height, a 50 cm adjustable gap, and 71 cm width—are carefully optimized based on ergonomic studies and clinical datasets to ensure both comfort and imaging performance.
A major advantage of the WT-PET system lies in its ability to significantly streamline clinical workflow. By eliminating the need for a patient bed and minimizing staff involvement in positioning, the system reduces setup time and increases overall throughput. With scan durations as short as 30 seconds and the ability to handle up to 12 patients per hour, WT-PET has the potential to dramatically improve efficiency in busy imaging centers. This is particularly valuable in regions with high demand for PET imaging, where scanner availability is often a limiting factor.
From a technical perspective, the system employs monolithic detectors capable of high spatial resolution, depth-of-interaction (DOI) measurement, and time-of-flight (TOF) capabilities. These features contribute to more uniform image resolution—below 2 mm—across the imaging field, which is an improvement over many traditional systems. Despite using approximately 50% less detector material due to its planar configuration, the WT-PET maintains competitive sensitivity (around 120 kcps/MBq), approaching that of larger cylindrical long axial field-of-view scanners. This reduction in detector area not only lowers system cost but also contributes to a smaller physical footprint, making installation more feasible in constrained clinical environments. Another important benefit is the more efficient use of radiotracers. The combination of high sensitivity and rapid acquisition enables a reduction of approximately 66% in the required tracer activity per patient, which has implications for cost savings. Further savings on system cost were investigated by simulating sparse configurations.
However, the WT-PET concept also introduces several challenges. Patient motion is a concern when scanning in an upright position, but this is mitigated through rapid acquisition times, ergonomic supports such as headrests and adjustable hand grips, and real-time feedback systems. The absence of an integrated CT scanner for attenuation correction is addressed with deep learning–based methods that estimate attenuation maps directly from PET data. Additionally, the planar geometry results in limited-angle sampling, which can affect image reconstruction. This is compensated for by leveraging the system’s large axial acceptance angle, along with DOI and TOF information, supplemented by advanced reconstruction algorithms and AI-based corrections. Following extensive simulation studies and reconstruction optimization, the WT-PET system is currently under construction, representing a promising step toward more efficient, accessible, and patient-friendly PET imaging. A 2-row bench top has been set-up and first lab measurements are ongoing.
| Track | TBPET |
|---|---|
| Presentation type | Oral |