Sadr Momtaz N, Tabebi S J, Mahmode M,
Volume 65, Issue 13 (3-2008)
Abstract
Background: Assessment of different strategic in disaster planning in selected countries.
According to the international report indicating that IRAN is among the seven countries
most susceptible to disaster, experiencing 31 known disasters out of 40 in the world,
occurrence of 1536 moderate to severe earthquake, during 1370-80 and 712 other disasters
at the same period it seems necessary to design a disaster plan.
Methods: This research is a comparative-descriptive and case based study in which the
researcher used random sampling process in selecting the statistical society from both
developed and developing countries. In this goal oriented research the necessary
information are extracted from valid global reports, articles and many questionnaires
which were subjected to scientific analysis.
Results: Studying different countries (which includes: Canada, Japan, India, USA,
Turkey, Pakistan and Iran) shows that there is a direct relationship between the level of
countries development and their success in disaster planning and management (including
preventive measures and confrontation). In most of the studied countries, decentralized
planning caused many professional planners participate in different levels of disaster
management which ultimately led to development of efficient and realistic plans which in
turn decreased the catastrophic effects of disasters dramatically. The results of the
aforementioned countries showed that a balanced approach to disaster plan with
investment in prophylactic area is very important.
Conclusion: As our country uses a centralized strategy for disaster management which
has proven its ineffectiveness, the researcher suggests that we should change our
approach in disaster management and let our planners participate from all levels include:
provincial, rural and etc. This will led to a reality based planning and using all potential
capacities in disaster management. According to this study it will be possible to use
prophylactic delusions and to mitigate the outcome of threatening disasters.
Sahel Heydarheydari , Negin Farshchian , Abbas Haghparast , Seyed Masoud Rezaeijo,
Volume 75, Issue 11 (2-2018)
Abstract
Background: In three-dimensional conformal radiation therapy (3D-CRT), contrast-enhanced CT (CECT) image is commonly used to assist radiation oncologists in diagnosing regions of interest, so that normal and target tissues can be better delineated. CECT causes the temporary increase in the CT number and the corresponding electron density (ρe). Administrated contrast agents (CA) during CT simulation and altering the ρe of structures can be effective on radiation calculations and dose-volume histograms (DVHs) in radiotherapy treatment planning. Therefore, present study was designed and performed to determine the influence of the administrated CA on DVHs.
Methods: Current study performed as a self-controlled clinical trial study with before/after method at Imam Reza Hospital, Kermanshah City, during the period from June 2015 till August 2016. Ten patients with pelvic cancer included in this study through simple sampling. Cases with prior reactions to CA, diabetes, renal diseases, and asthma were excluded. Two sets of CT-scans were taken for each patient in the same position and coordinates. Primary study sets contained pre-contrast images and secondary study sets were performed post-contrast. Both sets of CT images were transferred to the treatment planning system (ISOgray® software, Version 4.1.3.23 L, DOSIsoft®, Cachan, France). All treatment plans were generated on pre-contrast and subsequently copied to the post-contrast CT. Quantitative calculations were performed in treatment planning including the difference in ρe before and after CA administration.
Results: The prostate (1.27%), the bladder (0.62-0.79%) and the rectum (0.43-0.56%) showed the largest changes in average ρe increase. The results confirm the expected relationship of increasing attenuation, CT number, and ρe with increased tissue density due to the CA. However, the DVHs showed insignificant difference between pre-and post-contrast CTs for 18 MV photon beam.
Conclusion: The results showed statistical insignificant difference between with and without CA CTs treatment plan in pelvic field for targets and OARs. These results may serve as a reference to justify the use of CECT data sets for 3D-CRT planning of pelvic region cancers using DosiSoft ISOgray system.
