Naslov
Introducing computed tomography low dose protocol for sinuses at University Hospital Rijeka

Autori
Diklić, Ana ; Šegota, Doris ; Valković Zujić, Petra ; Dodig, Doris ; Banušić, Goran ; Jurković, Slaven

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Zbornik sažetaka 7. Kongresa hrvatskog društva radiologa i 3. Hrvatski neuroradiološki kongres / - , 2018

Skup
7. kongres Hrvatskog društva radiologa ; 3. hrvatski neuroradiološki sastanak

Mjesto i datum
Split, Hrvatska, 04.10.2018. - 07.10.2018

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
optimization, CT

Sažetak
Aim Computed tomography (CT) is considered to be a high dose radiological procedure. The speed and ease of performing this imaging procedure has resulted in over-stretching the use of this modality. A lot of effort has been made to create a „so called“ low dose protocols in order to individually adapt the dose to the clinical indication. CT of paranasal sinuses is frequently performed at University Hospital Rijeka. Thin axial CT images have become an essential aid in the treatment of sinus disease as a mandatory preoperative diagnostic tool used for the navigation during the functional endoscopic sinus surgeries (FESS). The population undergoing this exam is usually relatively young and requires follow-up exam. Special attention must be payed to the eye lens and thyroid gland because these radiosensitive organs are exposed to direct or scattered radiation. Therefore, we decided to implement a low dose protocol in our clinical practice dedicated to the given indication. Methodology Up to the time of this research a standard protocol for sinuses (120 ref. kV, 50 ref. mAs, kV and tube current modulation turned on) was used regardless of the indication. Low dose protocols for paranasal sinuses have already been published with different dose reduction strategies. In order to decide on the protocol to be used, several measurements were made. For the initial evaluation of the image quality anthropomorphic phantom was used. It was scanned with our standard protocol and four other scanning protocols with dose reduction on the 256-slice Siemens Definition Flash. Dose indicator values CTDIvol and DLP were recorded. These images were evaluated by two independent radiologists. Average image quality score was assigned to every protocol. Signal to Noise Ratio (SNR) was measured in three different anatomical regions. Following the phantom evaluation, clinical trial was performed and clinical images were evaluated. Results After the overall evaluation, the standard helical protocol was replaced with a low dose protocol (80 kV, 40 mAs, kV and tube current modulation turned off, axial mode). It resulted with a reduction of CTDIvol from 5, 4 mGy to 2, 2 mGy. SNR and image quality were consequently decreased but to an acceptable level for the given indication. Conclusion Regarding the localization of structures used for FESS, a new low dose protocol indicates sufficient accuracy at a lower dosage level.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Temeljne medicinske znanosti

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