Copper Filtration and kVp: Effect on Entrance Skin Exposure

Area of Science:

• Radiologic Technology
• Medical Imaging Physics

Background:

• Radiographic image acquisition relies on technical factors influenced by patient and anatomical considerations.
• Analog systems have limitations in data recording range, unlike digital receptors which offer wider latitude and patient-centered adjustments.

Purpose of the Study:

• To investigate the interplay between milliampere seconds (mAs), kilovoltage peak (kVp), and copper filtration on exposure indicators and entrance skin exposure (ESE).
• To compare these effects across both analog and digital imaging receptors.

Main Methods:

• Utilized 2-tailed t-tests for statistical analysis.
• Employed hip and knee phantoms to simulate patient anatomy.
• Varied kVp, mAs, and introduced 0.1 mm copper filtration.

Main Results:

• Increasing kVp and copper filtration while reducing mAs decreased ESE by 64% on a hip phantom (151 mR to 54.4 mR).
• A similar reduction of 51% in ESE was observed on a knee phantom (27.2 mR to 13.4 mR).

Conclusions:

• Findings support the development of dose reduction protocols in radiology.
• Digital radiography's wide latitude enables minimized patient exposure without compromising diagnostic image quality.