CARDIAC SUBMILISIVERT VOLUME (SCREENING) CT

Purpose of study: Exposure of patients to X-ray doses is rather high during coronary angiography. The aim of our study is to demonstrate the possibility of radiation dose reduction during the imaging of coronary arteries by adjusting the examination parameters during CT scanning. Dynamic volume CT scanner was used to obtain images. Main advantages of this CT device and these types of scanning protocols are dose reduction, small amount of contrast medium, duration of examination, noninvasivness.

Methods: The imaging was carried out on the CT Aquilion One with 320 row detector. 21 patients (19 males, 2 females, average age 37,5 years, heart rate ±3,7bpm) were examined using customized scan protocol. This protocol was based on patient's body mass index (BMI) (23,8±1,9). The examination parameters of the protocol (voltage 100 kV, tube current 200-570MA, scan range 10-16cm, rotation time 0,35s) were adjusted for each patient.

Results: The goal was to decrease amount of radiation bellow 1mSV without reduction of image quality. Based on our results, to meet the goal, the scan range is adjusted to the BMI and tube current. In our study we met our criteria in almost all patients , only one patient had BMI 30 and his radiation dose had to be increased above 1 mSV.

Conclusion: Adjustement of the examination parameters can lead to a significant reduction of radiation dose. This examination protocol can be used in certain patients, whose BMI is not too high (idela below 26). In indicated cases, this can be used as standard protocol, which reliably shows coronary arteries.