Putting it all together
Summing up, Pelc said his modest proposal for a more efficient CT scanner consists of several components working together, including the following:
- An energy-discriminating photon-counting detector (benefits: no electronic noise, higher geometric efficiency, optimal energy weighting)
- Dynamic bow tie (reduce dose, lower peak count rate)
- Modest gantry rotation speed (e.g., 1 sec, control count rate)
- Modest beam width (e.g., 1 cm, mitigate scatter and cost)
- No (or at least a coarse) antiscatter grid to eliminate associated geometric efficiencies
- Advanced reconstruction
In particular, the dynamic bow tie is a simple solution -- the low-hanging fruit of the more efficient scanner, he called it. The dynamic bow tie will be very helpful because it lowers the beat count rate and eases the workload of the photon-counting detector, according to Pelc.
The proposed scanner would have twice the spatial resolution of any clinical scanner currently on the market, and it represents "the largest spatial improvement we've had since 1980," leading to clinical benefits so substantial they cannot be predicted, he said. And, of course, spectral data would be available on all scans.
"I think the speed of this scanner would be sufficient for most applications, except for cardiac and whole-organ perfusion studies, which it would not support," Pelc said. And it will do all these things "at about one-fifth the dose of current systems, with comparable or better low-contrast performance."
Новый тип детекторов не за горами...