Voltaj ve Akım Değerlerinin Hasta Dozu Üzerindeki Etkilerinin CTDI Fantomu ile Araştırılması

Year 2019, Volume: 14 Issue: 2, 327 - 334, 30.11.2019

İsmail Hakkı Sarpün Aysun İnal Buket Çeçen

https://doi.org/10.29233/sdufeffd.605430

Cited By: 1

Abstract

Bilgisayarlı
tomografi (CT) günümüzde etkin bir şekilde kullanılan modern bir cihaz olup, tanısal
görüntülemede çok önemli bir yer tutmaktadır. Bu çalışmanın amacı, CT’de tüp voltajı (kVp), tüp akımı
(mAs) ve kesit kalınlığı değerlerini değiştirerek farklı çaplara sahip biri 16 cm çapında ve diğeri 32 cm çapında olan su eşdeğeri
silindirik iki adet fantomda
doz değişimlerini incelemektir. İyonizasyon odası ile okunan soğurulan
doz değerleri bilgisayarda var olan bir paket programı
yardımıyla ilgili parametrelere çevrilmiştir. Belli bir hacim için
hesaplanan CTDI_vol ve kesit alınan uzunluk boyunca aldığı toplam doz
değerini veren DLP değerleri karşılaştırılmıştır. Çalışma sonuçlarından da
görüldüğü gibi, doz artışı akım ve voltaj değerini arttırdıkça yükselmektedir.
Özellikle kafa fantomu örneğindeki gibi küçük ve zayıf hastalarda doz artışı
daha fazladır.

Keywords

CT, CTDI, Doz, Fantom

Supporting Institution

Akdeniz Üniversitesi BAPK

Project Number

FYL-2019-4804

Thanks

Bu çalışma, Buket Çeçen’in Yüksek lisans tez çalışması olup Akdeniz Üniversitesi BAPK FYL-2019-4804 nolu proje ile desteklenmiştir.

Effects of Voltage and Current Values to Patient Dose by CTDI Phantom

Abstract

Computed tomography
is a modern device and plays an important role in diagnostic imaging. The aim
of this study was to examine the dose changes in two water-equivalent
cylindrical phantoms with different diameters, one 16 cm in diameter and the
other 32 cm in diameter, by changing the tube voltage (kVp), tube current (mU)
and slices thickness values in CT. The absorbed dose values obtained by the
ionization chamber were converted to the relevant parameters by means of a
package program available on the computer. The calculated CTDI_vol
for a given volume and the DLP values giving the total dose value taken during
the cross-sectional length were compared. As can be seen from the results of
the study, the dose increases with increasing the current and voltage values.
Especially in small and thin patients such as the head phantom, the dose
increase is higher.

Keywords

CT, CTDI, Dose, Phantom

Project Number

FYL-2019-4804

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