Background: X-ray computed tomography (CT)
examinations deliver a significant amount of radiation
doses to patients comparing to conventional radiography
examinations. The objective of the current
study was to analyze and investigate the average
patient received dose from axial and spiral CT exams
in a medical imaging center. Material and Methods:
In this study, the patient imaging technique, weight
and height were recorded. The patients’ doses
provided by CT unit in terms of CTDIw were also
recorded. Then, other dosimetric quantities including
dose-length product (DLP) and effective dose were
calculated for each patient using the recorded data.
The average values were obtained for all the studied
dosimetric quantities. Also, their distribution in terms
of examined regions and imaging mode ie, axial and
spiral CT were analyzed by SPSS software. Results:
For all patients, the mean effective dose of 4.4 mGy
with the standard deviation of 9.2 was found. The
CTDIw for axial group was two times higher than spiral
ones. Conversely, the effective dose of axial group
was less than spiral group. Additionally, the effective
doses of 2.3 and 5.2 mSv were found for axial and
spiral, receptively. For both quantities of CTDIw and
effective dose, the observed difference between axial
and spiral modes were significant (P<0.001).
Conclusion: Our results showed that although the
patient doses in the current study was comparable
with the reported values by similar studies in other
countries, it was higher than the reported values of a
similar study in Iran. Exposure technique’s optimaization
and further review in routine CT examinations
were recommended. Iran. J. Radiat. Res., 2012 10(2):
89‐94
Ghavami S, Mesbahi A, Pesianian I. Patient doses from X-ray computed tomography examinations by a single-array detector unit: Axial versus spiral mode. Int J Radiat Res 2012; 10 (2) :89-94 URL: http://ijrr.com/article-1-940-en.html