| dc.description.abstract | Computed Tomography (CT) examinations
deliver higher patient dose in comparison
with other conventional x-ray examinations.
The aim of this study was to establish local
diagnostic reference levels (DRLs) for selected CT
examinations. This was a cross-sectional study
investigating local DRL in selected hospitals from
16 and 640 slice CT scanners in Sri Lanka. Three
hundred and fifty adult patients who underwent
CT scans of non-contrast and contrast brain,
contrast enhanced chest, HRCT chest, KUB,
contrast enhanced abdomen and chest-abdomen
examinations were included. Patients’ parameters
(height, weight, age and sex) and CT scan
parameters (kVp, effective mAs, total scan time,
slice thickness, CTDI (vol) and DLP) were collected.
The mean age of the patients was 53.25(±16) years
and the age range was 19 - 89 years. Local DRLs
were proposed to establish as the 75th percentile
of CTDI(vol) and the DLP values of NC- brain,
CE-brain, KUB, CE-chest, HRCT, CE-abdomen
and Chest-abdomen obtained from the 16 slice
CT machine. LDRLs for adult examinations
determined for NC- brain, CE-brain, KUB, CE-chest,
HRCT, CE-abdomen and Chest-abdomen
in terms of CTDI(vol) were 70.90 mGy, 141.8 mGy,
11.80 mGy, 17.70 mGy, 12.80 mGy, 45.27 mGy
and 27.02 mGy respectively. Effective doses for
the examinations NC-brain, CE-chest and CE-abdomen
were 2.60 mSv, 7.65 mSv and 20.7
mSv respectively and they were higher than
the AAPM reference levels. The study’s DRLs
values were generally higher than the ICRP 2007
recommended values. Moreover according to
the research, DRLs values of the commonest CT
examinations were generally higher than the
DRLs values of some other countries, requiring
further optimization process for these determined
DRLs. | en_US |
