SURVEY OF COMPUTED TOMOGRAPHY PRACTICE IN UKRAINE AND ESTABLISHMENT OF NATIONAL DIAGNOSTIC REFERENCE LEVELS FOR MOST COMMON CT EXAMINATIONS OF ADULTS.

This study reports results of the first nationwide survey of computed tomography (CT) practice in Ukraine and proposed national diagnostic reference levels (DRLs) for common CT examinations. The collected data included characteristics of CT scanners, frequency of CT exams per anatomical region, dose indices CTDIvol and dose-length product (DLP). National DRLs were proposed at the 75th percentile of median dose indices distributions for four common CT protocols: head without contrast (brain examinations for stroke and trauma), routine chest without contrast, single-phase contrast-enhanced CT of abdomen and pelvis and oncology protocol (chest-abdomen-pelvis). The results showed 4- to 9-fold variations of median dose indices between CT scanners for the same type of examination. The following values of the CTDIvol and DLP were proposed as national DRLs: 59 mGy and 1130 mGy•cm for head, 14 mGy and 492 mGy•cm for chest, 22 mGy and 845 mGy•cm for abdomen/pelvis and 2120 mGy•cm for oncological protocol.