SU-E-I-25: Performance Evaluation of a Proposed CMOS-Based X-Ray Detector Using Linear Cascade Model Analysis

Area of Science:

• Medical Imaging Technology
• X-ray Detector Development
• Neurovascular Applications

Background:

• Current flat-panel detectors for neurovascular imaging have limitations in resolution and noise performance.
• High-resolution, dynamic X-ray imaging is crucial for advancing neurovascular procedures.
• Existing technologies like the Micro-Angio Fluoroscope (MAF) show promise but have room for improvement.

Purpose of the Study:

• To theoretically estimate the performance of a proposed CMOS-based X-ray detector for neurovascular applications.
• To compare the projected performance of the CMOS detector against a high-resolution MAF system.
• To assess the potential of CMOS technology to overcome limitations of current detectors.

Main Methods:

• Linear cascade modeling was employed to analyze the signal and noise propagation through each stage of the imaging chain.
• The proposed detector model included a 300-micron CsI phosphor, 35-micron pixels, and a variable gain light image intensifier.
• Theoretical Modulation Transfer Function (MTF) and Detective Quantum Efficiency (DQE) were calculated and compared to the MAF detector using an RQA5 spectrum.

Main Results:

• The linear cascade model predicted improved performance for the proposed CMOS detector across its imaging chain.
• At 5 cycles/mm, the CMOS detector achieved an MTF of 0.08 and DQE of 0.28.
• These results represent a significant improvement over the MAF detector's MTF (0.05) and DQE (0.07) at the same spatial frequency.

Conclusions:

• The proposed CMOS-based detector is expected to offer superior MTF and DQE compared to the MAF.
• The new design will also feature a slimmer physical profile, eliminating the need for a bulky fiber-optic taper.
• This CMOS detector represents a significant advancement over existing flat-panel detectors and is anticipated to be well-received by neuro-vascular interventionalists.