ARDIŞIK TORAKS VE ABDOMEN BT TETKİKLERİNDE TARAMA UZUNLUĞU VE RADYASYON DOZ PARAMETRELERİNİN KARŞILAŞTIRILMASI

Year 2021, , 278 - 281, 01.07.2021

Eray Atlı , Abidin Kılınçer Sadık Uyanık Umut Öğüşlü , Halime Çevik

https://doi.org/10.18229/kocatepetip.741211

Abstract

AMAÇ: Bu çalışma ile amacımız ardışık toraks ve abdomen BT tetkiklerinde tarama uzunluğu değişkenliğini ve tarama uzunluğunun radyasyon dozu parametreleri üzerine etkisini değerlendirmektir.
GEREÇ VE YÖNTEM: Merkezimizde, Ocak 2018 ve Aralık 2018 tarihleri arasında aynı hastaya ait ardışık toraks (n=85) ve abdomen BT (n=57) tetkikleri çalışmaya dahil edildi. Toraks BT tetkiklerinin % 39 (n=33)'u, abdomen BT tetkiklerinin % 51 (n=29)'i kadındı. BT radyasyon dozu parametreleri görüntü arşivleme iletişim sisteminden (picture archiving communications system, PACS) retrospektif elde edildi. Hacimsel BT doz indeksi (Volume CT dose index, CTDIvol) ve doz uzunluk çarpımı (dose length product, DLP) değerleri hasta protokolünden kaydedildi. Etkin doz (ED) ve tarama uzunluğu (TU) hesaplandı. Ardışık toraks ve abdomen BT tetkikleri kendi içinde (ilk tetkik ve ikinci tetkik olmak üzere) iki gruba ayrıldı, ve BT radyasyon dozu parametreleri ile TU değerlendirildi.
BULGULAR: Toraks ve abdomen BT'si elde edilen hastaların ortalama yaşı sırasıyla 58±16 ve 51±16'dır. Her iki tetkik bölgesinde ardışık BT tetkikleri arasında DLP ve ED değerleri arasında istatiksel fark saptanmadı (p>0,05). Ardışık tetkikler arasında CTDIvol değeri açısından toraks BT grubunda anlamlı fark bulunmazken (p=0,724), abdomen BT grubunda anlamlı fark göstermektedir (P=0,042). Tarama uzunluğunun tetkikler arasındaki ortalama farkı toraks BT için 3,3 ± 2,6 cm, abdomen BT için 3,1 ± 2,5 cm olarak hesaplandı. Her iki tetkik bölgesinde tarama uzunluğu ardışık tetkikler arasında anlamlı farklılık göstermemektedir (p>0,05).
SONUÇ: Ardışık toraks ve abdomen BT tetkiklerinde, tarama uzunluğu açısından DLP ve ED'ye etki edecek bir farklılık saptanmadı. Ardışık tetkiklerde TU açısından fark saptanmamasına rağmen, BT çekimlerinde TU taranan anatomik bölgede tanısal bilgi kaybına neden olmayacak en kısa şekilde ayarlanmalıdır.

Keywords

BT, tarama uzunluğu, CTDIvol, , DLP

Supporting Institution

Yok

Project Number

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Thanks

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COMPARISON OF SCAN LENGTH AND RADIATION DOSE PARAMETERS IN CONSECUTIVE THORACIC AND ABDOMINAL CT EXAMINATIONS

Abstract

OBJECTIVE: The aim of this study is to evaluate the scan length variability and the effect of the scan length on radiation dose parameters in consecutive thoracic and abdominal CT examinations.
MATERIAL AND METHODS: Patients who underwent consecutive thoracic (n = 85) and abdominal CT (n = 57) examinations between January 2018 and December 2018 were included in this study. Thirty-nine percent (n = 33) of the thoracic CT examinations and 51 % (n = 29) of the abdominal CT examinations were performed on women. CT radiation dose parameters were obtained retrospectively from picture archiving communications system. Volume CT dose index (CTDIvol) and dose length product (DLP) values were recorded from the patient protocols. Effective dose (ED) and scan length (SL) were calculated. Consecutive thoracic and abdominal CT examinations were divided into two groups (first examination and second examination), and CT radiation dose parameters and SL were evaluated.
RESULTS: The mean age of patients in both thoracic and abdominal CT groups were 58±16 and 51±16 years old, respectively. There was no statistical difference between consecutive CT examinations in the relevant regions in terms of DLP and ED values (p> 0.05). CTDIvol were similar between consecutive examinations in the thoracic CT group (p=0.724), whereas there was significant difference between consecutive examinations in the abdominal CT group in terms of CTDIvol (p=0.042). The mean differences of SL in CT examinations were 3.3±2.6 cm for thoracic CT group and 3.1±2.5 cm for abdominal CT group. There was no significant difference in both consecutive thoracic and abdominal CT examinations in terms of SL (p> 0.05).
CONCLUSIONS: In consecutive thoracic and abdominal CT examinations, there was no difference in terms of SL that can affect DLP and ED. Although there is no difference in terms of SL between consecutive thoracic and abdominal CT examinations, SL must be adjusted as short as possible since it will not cause any loss in the diagnostic information in the region of interest.

Keywords

Computed tomography, Scan length, Volume computed tomography dose index

Project Number

Yok

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