METHOD: A total of 2247 PET/CT patients with normal glucose level underwent 18F-FDG-whole body imaging procedures. The 18F-FDG dose of 3.7MBq per kg of patient weight administered via intravenous infusion. For CT parameters, kilovoltage of 140keV and current of 40 mAs were used for all studies. All the acquired images collected retrospectively and the effective dose was calculated for each patient using algorithm adapted from ICRP Publication 106, modified for patient weight and patient blood volume. The estimated effective doses were evaluated for patients' body weight and BMI.
RESULTS: The mean of total effective dose and standard deviation is approximately 15.08(4.52) mSv using ICRP algorithm. 56% of total patient has normal BMI and their average total effective dose is 13.6mSv. Underweight patients' effective dose can be as low as 9.6mSv even using diagnostic CT protocols.
CONCLUSION: The effective dose of PET/CT procedure in present study is one of the lowest although using diagnostic parameters for CT acquisition compared to published data worldwide. This is due to the improved sensitivity of PET and complex reconstruction technique that maintains the image quality. A significant association between body weight, BMI and effective dose is reported in present study. Therefore, it is suggested that attention must be given for underweight and ideal BMI patients while prescribing FDG activity and CT imaging parameters in order to minimize the effective dose. The effective dose reported in present study can be considered as an upper limit for effective dose in PET/CT patients with normal BMI. This upper limit can be treated as a standard limit when optimizing imaging parameters, developing algorithm for image reconstruction and prescribing activity for patients. This practice could fulfill ALARA principle that could reduce cancer risk.
OBJECTIVES: This study aimed to determine the antigen relatedness and efficacy of different IB vaccine strains against a challenge with MV and QX-like strains.
METHODS: The antigen relatedness and the ability of different IB vaccine strains in conferring protection against MV and QX-like were assessed based on the clinical signs, macroscopic lesions, and ciliary activity.
RESULTS: The MV strain IBS037A/2014 showed minor antigenic subtype differences with the vaccine virus Mass H120 and 4/91 strains but showed major antigenic subtype differences with the K2 strain. The Malaysian QX-like strain IBS130/2015 showed major antigenic subtype differences with the MV strain IBS037A/2014 and the vaccine strains except for K2. Chickens vaccinated once with Mass (H120) or with non-Mass (4/91 and K2) developed antibody responses with the highest antibody titer detected in the groups vaccinated with H120 and 4/91. The mean ciliary activities of the vaccinated chickens were between 56 to 59% and 48 to 52% in chickens challenged with IBS037A/2014 and IBS130/2015, respectively. The vaccinated and challenged birds showed mild to severe lesions in the lungs and kidneys.
CONCLUSIONS: Despite the minor antigenic subtype differences, a single inoculation with Mass or non-Mass vaccines could not protect against the MV IBS037A/2014 and QX-like IBS130/2015.
Methods: This study was conducted to compare the outcomes of early and late tracheostomies in severe TBI. Only severe TBI patients who were admitted to the Neurosurgery High Dependency Unit (NHDU), Hospital Sultanah Aminah (HSA), Johor Bahru, Johor, Malaysia and who had underwent a tracheostomy were recruited. Three main outcomes noted: duration on ventilation, length of NHDU stay and rate of ventilator associated pneumonia (VAP).
Results: Out of 155 patients, 72 (46.5%) were in early tracheostomy group (ETG) and 83 (53.5%) were in late tracheostomy group (LTG). The majority of the participants, 95 (61.3%) were ethnic Malays. The mean duration on ventilator use was 2.65 days (1.57) for ETG and 5.63 days (2.35) for LTG. While, mean NHDU stay was 4.75 days (1.98) for ETG and 9.77 days (2.70) for LTG. Upon independent t-test, early duration of tracheostomies had shown significant outcome in reducing length of NHDU stay, (P < 0.001) and had shortening participants' time on mechanical ventilator (P < 0.001). Then, based on forward multiple logistic regression test, there were significant association between comorbid (P = 0.003) and tracheostomy (P = 0.020) towards presence of VAP when adjusted for other variables.
Conclusion: In this study it was found that early tracheostomy was significant in shortening the duration on ventilator, reducing the length of NHDU stay and reducing the rate of VAP.