1.Effective Atomic Number based on Energy Dispersive X-Ray (EDX) Analysis and Carbon Hydrogen Nitrogen (CHN) Analysis for Phantom Material in Medical Physics Applications
Siti Hajar Zuber ; Nurul Ab. Aziz Hashikin ; Mohd Fahmi Mohd Yusof ; Rokiah Hashim ; Mohd Zahri Abdul Aziz
Malaysian Journal of Medicine and Health Sciences 2021;17(No.4):116-121
Introduction: In medical physics applications, effective atomic numbers are often employed to set apart and specify
the interaction of ionizing radiation with matter. Methods: The effective atomic number of soy-lignin bonded with
Rhizophora spp. particleboards were analyzed using Energy Dispersive X-ray analysis and Carbon Hydrogen Nitrogen
Analyzer. The effective atomic number were compared and recorded with reference to the effective atomic value
of water. Results: The result showed that the effective atomic number calculated for adhesive bound Rhizophora spp.
samples were close to effective atomic value of water, with 3.34 – 3.47 % differences by using Energy Dispersive
X-ray and 6.47 – 6.78 % differences by using Carbon Hydrogen Nitrogen analysis. The result revealed that through
Energy Dispersive X-ray method, the effective atomic number was much closer to water compared to Carbon Hydrogen
Nitrogen analysis. Conclusion: Despite the availability of hydrogen content in the samples in Carbon Hydrogen
Nitrogen analysis, Energy Dispersive X-ray method was much more preferred and gave better result compared to
Carbon Hydrogen Nitrogen analysis thus provide a compelling argument for the use of Energy Dispersive X-ray
method to measure the effective atomic number of Rhizophora spp. particleboard in medical physics applications.
2.Scoping Review on Gonadal Effects in Patients with Pelvic Irradiation
Siti Hajar Zuber ; Nor Shazleen Ab Shukor ; Rafidah Zainon
Malaysian Journal of Medicine and Health Sciences 2021;17(No.4):306-312
This scoping review aimed to review studies on gonadal effects and time of recovery post-irradiation, and the approaches taken to manage the condition. A literature search was performed via three directories and databases
including PubMed, Cochrane Library and Google Scholar. A total of 41 articles fulfilled the inclusion criteria of the
study. The study populations primarily involved rectal cancer and Hodgkin’s lymphoma. In general, there were 65 %
of cases reported in female involved ovarian failure and dysfunction, while 36.4 % of cases reported in male showed
hypogonadism, as the side effects from pelvic irradiation. The most common interventions were pre-treatment interventions, such as ovarian transposition. However, information on the time of recovery was limited from these studies.
The review shows that more evidences exist for the potency and effectiveness of pre-treatment interventions such as
ovarian transposition in preserving the ovarian function post pelvic irradiation. Expansion of this review on participants with identical criteria can be performed, to permit further understanding of the post-irradiation gonadal effects.
3.Dosimetric Study of Custom-made Pelvic Perspex Phantom using Single-Energy Mode (SECT) and Dual-Energy Mode (DECT) Computed Tomography
Siti Hajar Zuber ; Nursyatina Abdul Raof ; Rafidah Zainon ; Abd Aziz Tajuddin
Malaysian Journal of Medicine and Health Sciences 2021;17(No.2):72-77
Introduction: A custom-made Perspex male pelvic phantom was developed to measure and to compare absorbed,
surface and effective doses obtained from Single-Energy and Dual-Energy Computed Tomography (SECT & DECT).
Methods: A customised Perspex pelvic phantom that mimicked male Asian reference size was scanned with SECT
mode at 80 kV, 100 kV, 120 kV and 140 kV. In addition, the fabricated phantom was also scanned with DECT mode
at 80/140 kV. Thermoluminescence dosimeters (TLD) were used to measure the charges and doses obtained from
the TLD calibration curve. The absorbed dose, surface dose and effective dose obtained from SECT and DECT were
measured and compared between these two modes. Results: The DECT showed 55.9 % dose reduction compared to
SECT at 140 kV tube voltage. It shows that DECT can be used with radiation dose sparing, and it is in good agreement
with routine CTDI phantom study. The effective dose of DECT of the abdominal imaging was within the acceptable
effective dose limit of AAPM Report No. 96. This study also found that the surface dose was lower than values reported in previous studies for both modes. Conclusion: The fabricated Perspex phantom shows a great potential to be
considered as an alternative phantom for the commercially existing phantom in CT dosimetry application.