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Objectives: To propose a novel robust radiogenomics approach to the identification of epidermal growth factor receptor (EGFR) mutations among patients with non-small cell lung cancer (NSCLC) using Betti numbers (BNs). Materials and methods: Contrast enhanced computed tomography (CT) images of 194 multi-racial NSCLC patients (79 EGFR mutants and 115 wildtypes) were collected from three different countries using 5 manufacturers' scanners with a variety of scanning parameters. Ninety-nine cases obtained from the University of Malaya Medical Centre (UMMC) in Malaysia were used for training and validation procedures. Forty-one cases collected from the Kyushu University Hospital (KUH) in Japan and fifty-four cases obtained from The Cancer Imaging Archive (TCIA) in America were used for a test procedure. Radiomic features were obtained from BN maps, which represent topologically invariant heterogeneous characteristics of lung cancer on CT images, by applying histogram- and texture-based feature computations. A BN-based signature was determined using support vector machine (SVM) models with the best combination of features that maximized a robustness index (RI) which defined a higher total area under receiver operating characteristics curves (AUCs) and lower difference of AUCs between the training and the validation. The SVM model was built using the signature and optimized in a five-fold cross validation. The BN-based model was compared to conventional original image (OI)- and wavelet-decomposition (WD)-based models with respect to the RI between the validation and the test. Results: The BN-based model showed a higher RI of 1.51 compared with the models based on the OI (RI: 1.33) and the WD (RI: 1.29). Conclusion: The proposed model showed higher robustness than the conventional models in the identification of EGFR mutations among NSCLC patients. The results suggested the robustness of the BN-based approach against variations in image scanner/scanning parameters. [ABSTRACT FROM AUTHOR]

The growing use of peripherally inserted central catheters (PICCs) has led to an increased risk of central line-associated bloodstream infection (CLABSI), necessitating the development of strategies to address this issue. This study evaluated the implementation of a Comprehensive Unit-Based Safety Program (CUSP) for the reduction of CLABSI at a medical imaging department in a tertiary teaching hospital. The three CUSP phases included P1: baseline (October 2019 to June 2020), P2: implementation (July 2020 to March 2021), P3a and P3b: sustaining (April 2021 to December 2022). The CUSP followed by a technical intervention; silver-alginate-coated dressings were applied from April to December 2022 (P3b). All PICCs from a surgical ward were included. CLABSI rates were measured quarterly. The device utilization ratio was calculated by dividing the number of device days by patient days. A total of 213 PICCs were included. CLABSI rates decreased from 3.3 per 1,000 central line days (P1) to 2.7 (P2), then increased to 4.5 (P3a) but reduced the rate significantly to 1.8 (P3b) (rate ratio, 0.55; 95% confidence interval [CI], 0.29-0.99, p<0.05) and 0.9 per 1,000 patient days (rate ratio, 0.86; 95% CI, 0.64-1.16, p=0.31) following the introduction of silver-alginate-coated dressings. The device utilization ratio increased by 60%. The CUSP intervention led to a reduction rate of 45% overall. The introduction of CUSP led to decreased CLABSI following a technical intervention in the medical imaging department with sustainable improvements. [ABSTRACT FROM AUTHOR]

Alleviating acute pain and providing pain relief are central to caring for surgical patients as pain can lead to many adverse medical consequences. This study aimed to explore patients' experience of pain and satisfaction with postoperative pain control. A cross-sectional survey was carried out among 107 respondents who had undergone abdominal surgery in the surgical ward of an urban hospital using the Revised American Pain Society's Patient Outcome and Satisfaction Survey Questionnaires ( APS- POQ- R). Data were analysed using descriptive statistics and chi-square test. Chi-square test showed significant association between race ( P = 0.038), education level ( P ≤ 0.001), previous operation status ( P = 0.032) and operation status ( P ≤ 0.001). Further analysis on nominal regression, association between dissatisfaction with factors of operation status (46.09 (95% CI 7.456, 284.947)) and previous operation status (13.38 (95% CI 1.39, 128.74)) was found to be significant. Moderate to high levels of pain intensity in the last 24 h after surgery, as well as moderate to high rates of pain-related interference with care activities were most reported. Pain still remains an issue among surgical patients, and effective pain management and health education are needed to manage pain more effectively after surgery. [ABSTRACT FROM AUTHOR]

This study was undertaken to compare the entrance surface dose (ESD) and image quality of adult chest and abdominal X-ray examinations conducted at general practitioner (GP) clinics, and public and private hospitals in Malaysia. The surveyed facilities were randomly selected within a given category (28 GP clinics, 20 public hospitals and 15 private hospitals). Only departmental X-ray units were involved in the survey Chest examinations were done at all facilities, while only hospitals per- formed abdominal examinations. This study used the x-ray attenuation phantoms and protocols developed for the Nationwide Evaluation of X-rat' Trends (NEXT) survey program in the United States. The ESD was calculated from measurements of exposure and clinical geometry An image quality test tool was used to evaluate the low-contrast detectability and high-contrast detail performance under typical clinical conditions. The median ESD value for the adult chest X-ray examination was the highest (0.25 mGy) at GP clinics, followed by private hospitals (0.22 mGy) and public hospitals (0.17 mGy). The median ESD for the adult abdominal X-ray examination at public hospitals (3.35 mGy) was higher than that for private hospitals (2.81 mGy). Results of image quality assessment for the chest X-ray examination show that all facility types have a similar median spatial resolution and low-contrast detectability. For the abdominal X-ray examination, public hospitals have a similar median spatial resolution but larger low-contrast detectability compared with private hospitals. The results of this survey clearly show that there is room for further improvement in performing chest and abdominal X-ray examinations in Malaysia. [ABSTRACT FROM AUTHOR]

Pediatrics are more vulnerable to radiation and are prone to dose compared to adults, requiring more attention to computed tomography (CT) optimization. Hence, diagnostic reference levels (DRLs) have been implemented as part of optimization process in order to monitor CT dose and diagnostic quality. The noise index has recently been endorsed to be included as a part of CT optimization in the DRLs report. In this study, we have therefore set local DRLs for pediatric CT examination with a noise index as an indicator of image quality. One thousand one hundred and ninety-two (1192) paediatric patients undergoing CT brain, CT thorax and CT chest-abdomen-pelvis (CAP) examinations were analyzed retrospectively and categorized into four age groups; group 1 (0–1 year), group 2 (1–5 years), group 3 (5–10 years) and group 4 (10–15 years). For each group, data such as the volume-weighted CT dose index (CTDIvol), dose-length product (DLP) and the effective dose (E) were calculated and DRLs for each age group set at 50th percentile were determined. Both CT dose and image noise values between age groups have differed significantly with p-value < 0.05. The highest CTDIvol and DLP values in all age groups with the lowest noise index value reported in the 10–15 age group were found in CT brain examination. In conclusion, there was a significant variation in doses and noise intensity among children of different ages, and the need to change specific parameters to fit the clinical requirement. [ABSTRACT FROM AUTHOR]

Intensity-modulated radiotherapy (IMRT) treatment planning for head and neck cancer is challenging and complex due to many organs at risk (OAR) in this region. The experience and skills of planners may result in substantial variability of treatment plan quality. This study assessed the performance of IMRT planning in Malaysia and observed plan quality variation among participating centers. The computed tomography dataset containing contoured target volumes and OAR was provided to participating centers. This is to control variations in contouring the target volumes and OARs by oncologists. The planner at each center was instructed to complete the treatment plan based on clinical practice with a given prescription, and the plan was analyzed against the planning goals provided. The quality of completed treatment plans was analyzed using the plan quality index (PQI), in which a score of 0 indicated that all dose objectives and constraints were achieved. A total of 23 plans were received from all participating centers comprising 14 VMAT, 7 IMRT, and 2 tomotherapy plans. The PQI indexes of these plans ranged from 0 to 0.65, indicating a wide variation of plan quality nationwide. Results also reported 5 out of 21 plans achieved all dose objectives and constraints showing more professional training is needed for planners in Malaysia. Understanding of treatment planning system and computational physics could also help in improving the quality of treatment plans for IMRT delivery. [ABSTRACT FROM AUTHOR]

IMRT is a commonly used technique for radiotherapy. This is the first multicentre study conducted nationally for assessing the quality of IMRT delivery in participating centres by cross-checking local QA results with on-site measurements using novel MO Skin detector and a commercial two-dimensional planar detector. By using MOSkin, 40 measurement points were evaluated, with 18% (8 points) showing deviations of more than ±5% from the predicted dose, while 82% of the results were within the recommended tolerance level of ±5% for on-site and end-to-end IMRT/VMAT audits. Most centres passed the 95% points of the gamma criteria of 3%/3 mm for planar dose measurement, which is consistent with other similar studies and within the confidence limits recommended by AAPM TG119. By benchmarking their performance with the recommended tolerance levels for IMRT delivery, participating centres can improve their quality continuously. In conclusion, the study found that participating centres generally met the international guidelines for IMRT delivery standards. • The first multicentre IMRT dosimetry audit was carried out in Malaysia. • Institutional QA results were compared with MO Skin detector and a planar detector. • Point dose measurement showed 18% measurements with deviations of more than ±5%. • Most centres passed the 95% gamma passing criteria of 3%/3 mm. [ABSTRACT FROM AUTHOR]

Purpose: We present the implementation of e-learning in the Master of Medical Physics programme at the University of Malaya during a partial lockdown from March to June 2020 due to the COVID-19 pandemic., Methods: Teaching and Learning (T&L) activities were conducted virtually on e-learning platforms. The students' experience and feedback were evaluated after 15 weeks., Results: We found that while students preferred face-to-face, physical teaching, they were able to adapt to the new norm of e-learning. More than 60% of the students agreed that pre-recorded lectures and viewing videos of practical sessions, plus answering short questions, were beneficial. Certain aspects, such as hands-on practical and clinical experience, could never be replaced. The e-learning and study-from-home environment accorded a lot of flexibility. However, students also found it challenging to focus because of distractions, lack of engagement and mental stress. Technical problems, such as poor Internet connectivity and limited data plans, also compounded the problem., Conclusion: We expect e-learning to prevail in future. Hybrid learning strategies, which includes face-to-face classes and e-learning, will become common, at least in the medical physics programme of the University of Malaya even after the pandemic., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Objective: To understand the status of pre-procedural safety practices in radiological examinations at radiology residency training institutions in various Asian regions., Methods: A questionnaire based on the Joint Commission International Accreditation Standards was electronically sent to 3 institutions each in 10 geographical regions across 9 Asian countries. Questions addressing 45 practices were divided into 3 categories. A five-tier scale with numerical scores was used to evaluate safety practices in each institution. Responses obtained from three institutions in the United States were used to validate the execution rate of each surveyed safety practice., Results: The institutional response rate was 70.0% (7 Asian regions, 21 institutions). 44 practices (all those surveyed except for the application of wrist tags for identifying patients with fall risks) were validated using the US participants. Overall, the Asian participants reached a consensus on 89% of the safety practices. Comparatively, most Asian participants did not routinely perform three pre-procedural practices in the examination appropriateness topic., Conclusion: Based on the responses from 21 participating Asian institutions, most routinely perform standard practices during radiological examinations except when it comes to examination appropriateness. This study can provide direction for safety policymakers scrutinizing and improving regional standards of care., Advances in Knowledge: This is the first multicenter survey study to elucidate pre-procedural safety practices in radiological examinations in seven Asian regions.

Objective: This study measured the radiation exposure of the eye lens of medical personnel performing fluoroscopy and interventional procedures at the Sarawak General Hospital in Kuching, Sarawak, Malaysia. This study was the first in Malaysia to utilise in vivo radiation measurement relatively near the eye lens., Methods: 41 medical personnel performing 79 procedures were monitored for their eye lens exposure using the NanoDot™ optically-stimulated luminescence dosimeters (OSLD) taped to the outer canthus of their eyes. The air-kerma area product (KAP), fluoroscopy time (FT) and number of procedure runs were also recorded., Results: KAP, FT and number of runs were strongly correlated. However, only weak to moderate correlations were observed between these parameters with the measured eye lens doses. The average median equivalent eye lens dose was 0.052 mSv (ranging from 0.0155 to 0.672 mSv). The eye lens doses of primary operators were found to be significantly higher than their assistants due to the closer proximity to the patient and X-ray tube. The left eye lens of the operators received the highest amount of radiation due to their habitual positioning towards the radiation source., Conclusion: KAP and FT were not useful in predicting the equivalent eye lens dose exposure in interventional radiological procedures. Direct in vivo measurements were needed to provide a better estimate of the eye lens doses received by medical personnel during these procedures. This study highlights the importance of using direct measurement, such as OSLDs, instead of just indirect factors to monitor dose in the eye lens in radiological procedures., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Objective: Medical physics in Malaysia is still considered a young profession. This workforce survey aims to understand the status, aspirations, motivation and experiences of medical physicists (MPs) in the country. A subsection of this survey also aims to understand the role of women., Method: A survey was carried out between April 20 and May 30, 2018 by a working group under the Medical Physics Division of the Malaysian Institute of Physics (IFM). The survey form was designed using Google Form and sent to various public and private institutions nationwide that employed MPs registered with IFM., Results: A total of 106 responses (28% men and 72% women) were analysed. This represented 30% of the medical physics workforce. Majority of them had postgraduate degrees, but their clinical training is mostly obtained on the job with no certification. The number of low-ranking female MPs was disproportionately high. MPs worked long hours and achieving work-life balance (WLB) was a challenge. Factors that improved their WLB included working close to home, having a supportive manager and flexible working hours. Most MPs aspired to become professional and mentor younger compatriots, besides contributing to patient care and research. Gender discrimination was reportedly low., Conclusion: Medical physics in Malaysia is growing and has a strong representation of women. In future, they would probably take over the top management from their male counterparts, whose number had stagnated. A united effort was essential to set up a proper clinical training system to train clinically qualified MPs., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Purpose: Intensity Modulated Radiotherapy (IMRT) has changed the practice of radiotherapy since its implementation in the 1990s. The purpose of this study is to review current practice of IMRT in Malaysia., Methods: A survey on medical physics aspects of IMRT is conducted on radiotherapy departments across Malaysia to assess the usage, experience and QA in IMRT, which is done for the first time in this country. A set of questionnaires was designed and sent to the physicist in charge for their responses. The questionnaire consisted of four sections; (i) Experience and qualification of medical physicists, (ii) CT simulation techniques (iii) Treatment planning and treatment unit, (iv) IMRT process, delivery and QA procedure., Results: A total of 26 responses were collected, representing 26 departments out of 33 radiotherapy departments in operation across Malaysia (79% response rate). Results showed that the medical physics aspects of IMRT practice in Malaysia are homogenous, with some variations in certain areas of practices. Thirteen centres (52%) performed measurement-based QA using 2D array detector and analysed using gamma index criteria of 3%, 3 mm with variation confidence range. In relation to the IMRT delivery, 44% of Malaysia's physicist takes more than 8 h to plan a head and neck case compared to the UK study possibly due to the lack of professional training., Conclusions: This survey provides a picture of medical physics aspects of IMRT in Malaysia where the results/data can be used by radiotherapy departments to benchmark their local policies and practice., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

There is widespread anxiety and speculation about RF-EMF emissions by telecommunication base stations and structures, as it is perceived by some to be unsafe and a threat to public health. Scientists, medical experts, politicians, journalists, and mobile telecommunication company specialists are involved in an active debate on whether people are immune to RF or if we are gambling with our future. Interviews with 31 individuals from 7 stakeholder groups in Malaysia reveal that the residents' main concerns are that the telecommunication companies do not follow guidelines and as a result the telecommunication structures are constructed close to their homes, which they perceive as a threat to public health. Some residents also do not want these structures because of cultural reasons, while some are jealous over rental income received by the landlords. Meanwhile, the authorities entrusted with safe-guarding public health are involved in a blame game as there is no agency that is clearly in charge. The interviews also highlight that the current risk communication initiatives are more reactive rather than proactive, and that the authorities do not speak in one voice. Based on the outcome of the interviews, eleven recommendations are formulated to improve risk communication initiatives in Malaysia. The recommendations stress on repairing, building, and strengthening trust, because trust in agencies, along with credibility, determines risk communication initiatives' effectiveness. These strategies can also be effectively replicated across regions to deal with contestations over RF-EMF emissions and the impact on health.

This study was undertaken to compare the entrance surface dose (ESD) and image quality of adult chest and abdominal X-ray examinations conducted at general practitioner (GP) clinics, and public and private hospitals in Malaysia. The surveyed facilities were randomly selected within a given category (28 GP clinics, 20 public hospitals and 15 private hospitals). Only departmental X-ray units were involved in the survey. Chest examinations were done at all facilities, while only hospitals performed abdominal examinations. This study used the x-ray attenuation phantoms and protocols developed for the Nationwide Evaluation of X-ray Trends (NEXT) survey program in the United States. The ESD was calculated from measurements of exposure and clinical geometry. An image quality test tool was used to evaluate the low-contrast detectability and high-contrast detail performance under typical clinical conditions. The median ESD value for the adult chest X-ray examination was the highest (0.25 mGy) at GP clinics, followed by private hospitals (0.22 mGy) and public hospitals (0.17 mGy). The median ESD for the adult abdominal X-ray examination at public hospitals (3.35 mGy) was higher than that for private hospitals (2.81 mGy). Results of image quality assessment for the chest X-ray examination show that all facility types have a similar median spatial resolution and low-contrast detectability. For the abdominal X-ray examination, public hospitals have a similar median spatial resolution but larger low-contrast detectability compared with private hospitals. The results of this survey clearly show that there is room for further improvement in performing chest and abdominal X-ray examinations in Malaysia.

Objective: This study was undertaken to estimate mammographic breast glandularity in Malaysian women from radiographic data., Materials and Methods: A mammography X-ray unit was used to expose different thicknesses of phantom material of varying glandular and adipose composition at 27 kV. A least squares method was then used to fit the combined data of phantom glandularity, thickness, and milliampere-seconds. The subsequent fitted equation was then applied to calculate breast glandularity for 705 women who underwent diagnostic mammography, who were drawn equally from the three major ethnic groups of Malaysia: Malay, Chinese, and Indian. The difference in breast glandularity among ethnic groups was tested for significance using the nonparametric Kruskal-Wallis test., Results: The fitted equation gave an absolute error of less than or equal to +/- 8% when applied to the data from phantom exposure. The average breast glandularity of the study sample was 48.9% +/- 18.7%. Breast glandularity was found to decrease with breast thickness and age., Conclusion: No significant difference was seen in breast glandularity among the ethnic groups (p > 0.05, Kruskal-Wallis test).