Computed tomography (CT) is a non-invasive medical imaging technique employed in a broad variety of diagnostic applications, from detection and tracking of malignant tumors to guidance during interventional radiology procedures [Power et al., 2016]. CT urography (CTU) pertains to a multiple-phase CT scan that examines the urinary tract system’s organs [Noorbakhsh et al., 2019]. Renal calculi formation inside the kidneys is one of the most ordinary sources of urinary tract pathological conditions, such as infections and hematuria. As a consequence, the detection and assessment of urinary stones is of considerable importance [Sandor et al., 2003]. Additionally, CTU imaging is required during lithiasis treatment planning, prior to percutaneous or endoscopic interventions [Kalogeropoulou et al. 2009].                       ...

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Gender, age, and weight were documented for 198 patients submitted for CTU examinations. All the CTU examinations were performed at the CT Department of University Hospital of Patras from experienced radiologists and CT technologists during a six-year period.

     The clinical indications for CTU examination consisted of 119 patients with lithiasis, 26 patients with cancer, and 53 patients with other diseases of the urinary tract system. Lithiasis refers to the presence of stones that can originate in any part of the urinary tract. Imaging was also performed for detection of suspected cancer tumors or treatment response monitoring. Other diseases included several conditions such as pain in the lower back, obstructive uropathy and haematuria.

     Regarding the preparation of the patients, approximately 60 m prior to the examination, they...

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Patient’s gender, age and weight, per phase and per clinical indication, for the three-phase and four-phase protocols, and as a whole, are presented in Table 2. The study’s population consists of 96 males and 192 females. Patients’ mean (range) age is 58.2 (19-95) years whilst the mean (range) weight is 74.9 (48-125) kg. It should be underlined that this mean weight value is in line with the ICRP’s recommendations for DRLs determination [Vano et al., 2017].

     Sixty-three out of the total one hundred and nineteen patients referred for lithiasis were scanned with the three-phase protocol, while the four-phase protocol was selected for the rest fifty-six patients. Most of the patients (twenty out of twenty-six) referred for cancer were scanned with the four-phase protocol, whereas twenty-six  of the fifty-three patients referred for...

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This work establishes IDRLs for CTU examinations taking into account both the phases’ number and clinical indications. The mean and median values of the present study are similar or lower than those of the previously published surveys. The broad variation in literature’s reported CTDI_vol and DLP values reflects the diversity of utilized scanners in addition to the different technical parameters of the applied acquisition protocols. The proposed IDRLs will grant other Hospitals, both in Greece and abroad, the ability to evaluate their CTU practice. In order to optimize the ratio between a successful diagnosis and the eventual health harm due to unnecessary or undesired radiation exposure, the harmonic collaboration of all the involved parties is a prerequisite, from the patient to the CT technologist and the medical physicist responsible for the radiation...

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