**6. Evaluation of the metodology of imaging studies**

Generation of spiral CT units enabled the examination of large blood vessels for the first time as a substitute for the invasive conventional angiography, most importantly for aorta, extracranial arteries of the neck and skull base, main trunks of visceral arteries of thorax and abdomen and ilio-popliteal vessels. There have been numerous attempts to affirm spiral angiography for the exploration of 2nd and 3rd order arteries of parenchymatous organs, but diagnostic sensitivity was disappointing (33,39). Development of CT technology from the year 2000, enabled the start of new epoch with multidetector CT units, that brought amazing possibilities of image acquisition and spatial to temporal resolution ratio (30,31). In the same terms, a new postprocessing editing of transverse CT images was developed, offering faster, more detailed and accurate reconstruction possibilities in all planes. Definitely, MDCT examination established itself as diagnostically most sensitive in postprocedural evaluation of AAA and became method of choice in this field. In year 2007, exponential dose for the examination of infrarenal aorta using standard protocol at 64-slice unit, was approximatelly 6-8 mSv for both sexes. In obese patients it was somewhat higher (29). During the following 3 years, introducing new pulse generators and faster rotating tubes in clinical practice, exponential dose for CT exam of infrarenal aorta was lowered for 8-10 times, remaining the preoccupation of inovators until now.
