Primerjava dozne obremenitve in kakovosti rentgenograma pri slikanju kolena z in brez avtomatskega nadzora ekspozicije v splošni radiografiji : magistrsko delo

Janežič, Alja (author), Mekiš, Nejc (mentor), Škrk, Damijan (reviewer)

Uvod: Koleno je največji sklep v človeškem telesu in največkrat poškodovan sklep. Bolečina v kolenu je eden najpogostejših vzrokov obiska ambulante splošne medicine. Namen: Namen je ugotoviti, kako izbira avtomatskega nadzora ekspozicije (AEC) vpliva na dozno obremenitev pacienta pri slikanju kolena v anteroposteriorni (AP) in stranski projekciji. Metode dela: Raziskavo smo izvedli v dveh delih. V prvem delu smo merili vrednosti na fantomu. Naredili smo 20 slik, 10 z uporabo AEC in 10 z uporabo ročne ekspozicije. Drugi del smo opravili na 200 pacientih. Paciente smo razdelili v dve skupini. V prvi skupini so pacienti pri katerih smo uporabili AEC v drugi skupini pa ročne ekspozicijske pogoje. Pri vseh meritvah smo beležili obseg kolena, velikost polja, tokovni sunek in vrednost produkta doze in površine (DAP). Iz pridobljenih podatkov in slik smo izračunali še vrednosti vstopne kožne doze (VKD), razmerje signal-šum (SNR) in razmerje kontrast-šum (CNR). Rezultati in razprava: Raziskava na fantomu je pokazala, da je bil tokovni sunek v AP projekciji za 0,2 mAs večji pri ročni ekspoziciji, pri stranski ekspoziciji pa je bila razlika večja in sicer za 0,9 mAs. Vrednost DAP je pri AP projekciji za 3,1 µGym2 večja pri ročni ekspoziciji, pri stranski projekciji pa za 0,8 µGym2 prav tako pri ročni ekspoziciji. Pri pacientih je bila velikost polja večja pri AP projekciji za 9,1 cm2 pri ročni ekspoziciji, pri stranski projekciji pa je bila velikost polja za 16,6 cm2 večja pri AEC. Vrednosti DAP so bile pri AP projekciji večje za 1,4 µGym2 pri ročni ekspoziciji, pri stranskem slikanju do razlik pri vrednosti DAP ni prišlo. Obseg kolena je med protokoloma odstopal le za 0,7 cm. VKD je bila pri AP projekciji večja za 42,6 µGy, pri stranski projekciji pa za 20,6 µGy, v obeh primerih pri ročni ekspoziciji. Vrednosti SNR se pri AP projekciji razlikujejo za 8,2 %, pri stranskem slikanju pa za 1,2 %. Vrednosti CNR v AP projekciji se razlikujejo za 11,6 %, medtem ko pri stranskem slikanju za 0,1 %. Zaključek: Rezultati so pokazali, da slikanje kolen v AP projekciji in v stranski projekciji, priporočamo slikanje z uporabo avtomatskega nadzora ekspozicije.

• Language: Slovenian
• Keywords: magistrska dela, radiološka tehnologija, rentgensko slikanje kolen, AEC, ročna ekspozicija, DAP, VKD, SNR, CNR
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: ZF - Faculty of Health Sciences
• Place of publishing: Ljubljana
• Publisher: [A. Janežič]
• Year: 2021
• Number of pages: 56 str., [4] str. pril.
• PID: 20.500.12556/RUL-134088
• UDC: 616-07
• COBISS.SI-ID: 91328259
• Publication date in RUL: 23.12.2021

JANEŽIČ, Alja, 2021, Primerjava dozne obremenitve in kakovosti rentgenograma pri slikanju kolena z in brez avtomatskega nadzora ekspozicije v splošni radiografiji : magistrsko delo [online]. Master’s thesis. Ljubljana : A. Janežič. [Accessed 26 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=134088

Secondary language

• Language: English
• Title: The comparison of image quality and radiation dose in knee radiography with and without the use of automatic exposure control : master thesis

Abstract

Introduction: The knee is the largest joint in the human body. It is also the most commonly injured joint. Knee pain is one of the most common reasons for visiting a general practitioner. Purpose: The purpose is to determine how the choice of automatic exposure control (AEC) affect the patient’s radiation dose in anteroposterior (AP) and lateral projection in knee radiography. Methods: The study was conducted in two parts. In the first part of the study we took 20 exposures, 10 with AEC and 10 with manual exposure control. The second part of the study was performed on 200 patients. The patients were divided into two equal groups. In the first group we took images with AEC and in the second group with manual exposure control. Knee circumference, field size, anode current and dose area product (DAP) values were recorded in all patients. Entrance skin dose (ESD), sinal-noise ratio (SNR) and contrast-to-noise ratio (CNR) values were also calculated from the obtained data and images. Results and Discussion: A study on a phantom showed that the product of anode current in AP projection was 0.2 mAs higher at manual exposure control, and the difference was 0.9 mAs greater in lateral position at manual exposure control. The DAP value is 3.1 μGym2 higher in the AP projection at manual exposure and 0.8 μGym2 higher in the lateral position at manual exposure. Measurements on the patients showed that the field was 9.1 cm2 larger in the AP projection at manual exposure, and the field was 16.6 cm2 larger in the lateral projection at AEC. The DAP values were 1.4 μGym2 higher in the AP projection with manual exposure, and there were no differences in the DAP in lateral position. Knee circumference differed by 0.7 cm between protocols. In the AP projection, the ESD was 42.6 μGy higher with manual exposure, and in lateral position, the ESD value was 20.6 μGy higher at manual exposure. We also checked the image quality using the SNR and CNR parameters. The SNR values differed by 8.2% in the AP projection and by 1.2% in the lateral position. The CNR values in the AP projection differ by 11.6%, while the difference in the lateral position is 0.1%. Conclusion: The results show that knee imaging in AP projection and in lateral projection is recommended the use of AEC.

• Keywords: master's theses, radiologic technology, knee x-ray, AEC, manual exposure, DAP, ESD, SNR, CNR