Detector, collimator and real-time reconstructor for a new scanning-beam digital x-ray (SBDX) prototype

Area of Science:

• Medical Imaging
• Radiological Physics
• Biomedical Engineering

Background:

• Scanning-beam digital x-ray (SBDX) offers low-dose cardiac imaging by reducing scatter with a narrow beam.
• Limited x-ray fluence in previous SBDX systems restricted imaging capabilities.

Purpose of the Study:

• To develop an improved SBDX prototype with increased x-ray fluence for enhanced cardiac imaging.
• To evaluate the performance of the new prototype in terms of imaging quality and speed.

Main Methods:

• Constructed a new SBDX prototype featuring a wider x-ray beam, a larger-area CdTe photon counting detector (86% increase), and a multi-GPU real-time image reconstructor.
• Acquired 40,328 projections per 1/15s scan from 71x71 focal spot positions.
• Generated 32 tomosynthetic planes and a multiplane composite image per frame.

Main Results:

• The new SBDX prototype demonstrated a 63%-71% increase in noise equivalent quanta compared to the previous version.
• X-ray scatter fraction ranged from 3.9-7.8% in phantoms, slightly higher than the previous prototype (2.3-4.2%).
• Successfully performed coronary angiographic imaging at 15 frames/s with live display.

Conclusions:

• The enhanced SBDX prototype successfully increases x-ray fluence, enabling high-speed, real-time coronary angiography.
• The system provides multiplane and single-plane imaging options for cardiac procedures.
• Further optimization may be needed to mitigate the slight increase in scatter fraction.