Title: The Effects of Different Collimation size on signal to Noise Ratio (SNR) of Wrist Joint Radiograph PA Projection
Authors: Anak Agung Aris Diartama, Ni Putu Rita Jeniyanthi, I Nyoman Wiradarma, Rachel Monica Deovania Moningka, Langkir Sapto Adi, I Wayan Angga Wirajaya, , I Kadek Sukadana
DOI: https://dx.doi.org/10.18535/jmscr/v6i12.104
Abstract
Background: The quality of radiographic image will significantly affect diagnose. One of the factors used to evaluate digital image quality is signal to noise ratio (SNR)[1]. The use of excessive radiation field or collimation in radiological examination should be avoided in order to reduce the radiation dose[2]. Additionally, excessive collimation may increase scattered radiation, degrading the image quality[1]. In previous observations in practice, radiological examination of wrist joint often use large area radiation field. This study aims to determine the effect of the different size of collimation on the Signal to Noise Ratio of Wrist Joint examination
Purpose: To assess the effects of different collimationsize on SNR of wrist joint examination PA projection.
Method: This is quantitative studywith experimental approach, conducted atthe ATRO Bali laboratory. Wrist radiographs were acquired from 6 volunteers. The SNRof each radiograph was calculated with paired T-test on SPSS statistical software.
Result: The data was normally distributed(p> 0.05),therefore paired-T testwas performed, resulting inp <0.05, which means that there is a significant differenceof SNR in different collimation size of18x24 cm and 9x12 cm. The mean SNR value of the smaller collimation(9x12 cm)was higher than the larger size (18x24 cm).
Conclussion: There is a significant difference in the SNR value in different collimation size (18x24 cm and 9x12 cm), with smallercollimationsize resulted in a higher SNR.
Keywords: Collimation size, SNR, wrist joint radiograph.
