Dynamic flat panel detector versus image intensifier in cardiac imaging: dose and image quality

Area of Science:

• Medical Physics
• Radiology
• Cardiovascular Imaging

Background:

• Digital x-ray systems are crucial for cardiology procedures.
• Evaluating system performance is essential for patient safety and diagnostic accuracy.
• Image intensifiers (II) and dynamic flat panel detectors (FD) are key imaging technologies.

Purpose of the Study:

• To assess the dosimetric and imaging performance of a digital x-ray system in cardiology.
• To compare the performance of an image intensifier (II) with a dynamic flat panel detector (FD).
• To evaluate the accuracy of dose information in DICOM headers.

Main Methods:

• Measured Entrance Surface Air Kerma (ESAK) using polymethyl methacrylate (PMMA) phantoms of varying thicknesses.
• Assessed image quality using a test object, evaluated numerically (noise, SNR) and visually.
• Tested DICOM header information for dosimetry audit compliance.
• Compared II and FD systems across different field sizes and operational modes (cine, fluoroscopy).

Main Results:

• Similar Entrance Surface Air Kerma (ESAK) values were observed for both II and FD systems across tested conditions.
• Measured dose rates ranged from 19 to 589 microGy/frame (cine) and 5 to 95 mGy/min (fluoroscopy).
• The dynamic flat panel detector (FD) demonstrated superior image quality compared to the image intensifier (II) at equivalent dose settings.

Conclusions:

• Dynamic flat panel detectors (FD) offer improved image quality in digital x-ray systems for cardiology.
• FD systems have the potential for future dose reduction, particularly in digital cine runs.
• The evaluated system's 'study dosimetric report' is accurate and comprehensive, aiding dosimetry audits.