[Dose optimization for multislice computed tomography protocols of the midface]

Area of Science:

• Radiology
• Medical Imaging
• Radiation Dosimetry

Background:

• Multislice computed tomography (MSCT) is crucial for midface imaging.
• Optimizing MSCT protocols is essential for balancing diagnostic image quality with radiation dose reduction.
• Previous protocols may not fully leverage dose-saving techniques without compromising diagnostic efficacy.

Purpose of the Study:

• To determine optimal multislice computed tomography (MSCT) protocols for the midface.
• To achieve significant radiation dose reduction while maintaining adequate image quality.
• To evaluate specific parameters like tube current and voltage for midface CT scans.

Main Methods:

• MSCT of cadaveric midfaces was performed with progressively reduced tube current (mAs) at 120 kV and 80 kV.
• Image quality was qualitatively assessed by two radiologists using a five-point scale for sharpness, demarcation, and noise.
• Effective body dose and ocular lens organ dose were calculated, and interobserver agreement was determined.

Main Results:

• Adequate sharpness, demarcation, and image quality for lamellar bone evaluation were achieved at 120 kV/30 mAs.
• Acceptable overall image quality and noise levels were noted at 120 kV/40 mAs.
• Effective dose decreased from 1.89 mSv to 0.34 mSv, and ocular lens dose from 27.2 mSv to 4.8 mSv.

Conclusions:

• Optimized MSCT protocols using 30 mAs at 120 kV provide adequate image quality for midface imaging.
• This protocol results in a substantial dose reduction of approximately 70% compared to standard protocols.
• The findings support the implementation of lower dose MSCT protocols for midface examinations without compromising diagnostic value.