Analisis Nilai CT Number (CTN) dan Kualitas Citra dari Pengaruh Variasi Tegangan dan Arus Tabung Menggunakan Pesawat CT Simulator

Nisa Amalia Ansar; Syamsir Dewang; Satrial Male

doi:10.55451/jri.v7i2.291

Nisa Amalia Ansar Universitas Hasanuddin
Syamsir Dewang Rumah Sakit Tk. II Pelamonia Makassar
Satrial Male Rumah Sakit Tk. II Pelamonia Makassar

DOI: https://doi.org/10.55451/jri.v7i2.291

Keywords: CT Simulator, CT Number, SNR, CNR, image quality

Abstract

Background: The CT simulator is an integral part of radiotherapy treatment that can determine the target location and dose planning in images. Exposure factors such as tube voltage and current are important components that affect the resulting images. This study compares the effects of varying exposure factors on CT numbers (CTN) and image quality (spatial resolution, uniformity, SNR, and CNR).

Methods: This study used a Catphan®604 phantom with helical image acquisition on a CT simulator to obtain images. The voltage variations were 80, 100, 120, and 135 kV. Additionally, current variations of 50, 100, 150, and 200 mA were applied at both their maximum and minimum values.

Results: The study results indicate that variations in voltage tend to decrease CTN values and improve image quality. Conversely, variations in current do not result in significant changes in CTN values but tend to enhance the quality of the image. The optimal values for CTN and image quality were found at 100 kV and 200 mA.

Conclusions: The exposure factor of voltage significantly affects changes in CTN and image quality. Conversely, tube current does not have a significant impact on CTN. As the voltage and current increase, the image quality improves, but the resulting noise also becomes greater.