Australasian Physical and Engineering Sciences in Medicine 
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This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.Development of a 3D printed phantom for commissioning and quality assurance of multiple brain targets stereotactic radiosurgery
In conclusion, an SRS QA phantom was designed, and 3D printed and its use for performing complex MBT patient specific QA in a single delivery was demonstrated. (Source: Australasian Physical and Engineering Sciences in Medicine)
Source: Australasian Physical and Engineering Sciences in Medicine - January 29, 2024 Category: Biomedical Engineering Source Type: research
Evaluation of robustness of optimization methods in breast intensity-modulated radiation therapy using TomoTherapy
AbstractIntensity-modulated radiation therapy (IMRT) has become a popular choice for breast cancer treatment. We aimed to evaluate and compare the robustness of each optimization method used for breast IMRT using TomoTherapy. A retrospective analysis was performed on 10 patients with left breast cancer. For each optimization method (clipping, virtual bolus, and skin flash), a corresponding 50 Gy/25 fr plan was created in the helical and direct TomoTherapy modes. The dose-volume histogram parameters were compared after shifting the patients anteriorly and posteriorly. In the helical mode, when the patient was not shifted,...
Source: Australasian Physical and Engineering Sciences in Medicine - January 24, 2024 Category: Biomedical Engineering Source Type: research
Comprehensive characterisation of the IBA myQA SRS for SRS and SBRT patient specific quality assurance
AbstractThe myQA SRS (IBA) is a new to market 2D complementary metal oxide semiconductor detector array with an active area 140 × 120 mm2 and 0.4 mm resolution, making it a potential real-time dosimetry alternative to radiochromic film for stereotactic plan verification. Characterisation of the device was completed to assess performance. The dosimetric properties of the device were assessed for 6FF and 6FFF beams from a Varian TrueBeam STx with high definition multileaf collimator. Clinical suitability of the device for Patient Specific Quality Assurance was verified using ten SRS/SBRT plans, compared against othe...
Source: Australasian Physical and Engineering Sciences in Medicine - January 18, 2024 Category: Biomedical Engineering Source Type: research
RF energy harvesters for wireless sensors, state of the art, future prospects and challenges: a review
AbstractThe power consumption of portable gadgets, implantable medical devices (IMDs) and wireless sensor nodes (WSNs) has reduced significantly with the ongoing progression in low-power electronics and the swift advancement in nano and microfabrication. Energy harvesting techniques that extract and convert ambient energy into electrical power have been favored to operate such low-power devices as an alternative to batteries. Due to the expanded availability of radio frequency (RF) energy residue in the surroundings, radio frequency energy harvesters (RFEHs) for low-power devices have garnered notable attention in recent t...
Source: Australasian Physical and Engineering Sciences in Medicine - January 17, 2024 Category: Biomedical Engineering Source Type: research
Potential dosimetric error in the adaptive workflow of a 1.5 T MR-Linac from patient movement relative to immobilisation systems
This study highlights the dosimetric effect of using this in such workflows when there are relative patient-ppd displacements, as these are not visualized on MR imaging and the treatment planning system assumes the patient is fixed relative to the ppd. The online adapted plans of two example rectum cancer patients treated at a Unity MR-linac were perturbed by introducing relative patient-ppd displacements, and the effect was evaluated on plan dosimetry. Forty-eight perturbed clinical adapted plans were recalculated, based on online MR-based synthetic computed tomography, and compared with the original plans, using dose-vol...
Source: Australasian Physical and Engineering Sciences in Medicine - January 16, 2024 Category: Biomedical Engineering Source Type: research
Comparison of skin dose in IMRT and VMAT with TrueBeam and Halcyon linear accelerator for whole breast irradiation
This study aimed to compare skin doses of treatments using FFF and flattening filter (FF) beams for breast cancer. The study established treatment plans for left breast of an anthropomorphic phantom using Halcyon ’s 6-MV FFF beam and TrueBeam’s 6-MV FF beam. Volumetric modulated arc therapy (VMAT) with varying numbers of arcs and intensity modulated radiation therapy (IMRT) were employed, and skin doses were measured at five points using Gafchromic EBT3 film. Each measurement was repeated three times, an d averaged to reduce uncertainty. All plans were compared in terms of plan quality to ensure homogeneous target cove...
Source: Australasian Physical and Engineering Sciences in Medicine - January 15, 2024 Category: Biomedical Engineering Source Type: research
ColonGen: an efficient polyp segmentation system for generalization improvement using a new comprehensive dataset
AbstractColorectal cancer (CRC) is one of the most common causes of cancer-related deaths. While polyp detection is important for diagnosing CRC, high miss rates for polyps have been reported during colonoscopy. Most deep learning methods extract features from images using convolutional neural networks (CNNs). In recent years, vision transformer (ViT) models have been employed for image processing and have been successful in image segmentation. It is possible to improve image processing by using transformer models that can extract spatial location information, and CNNs that are capable of aggregating local information. Des...
Source: Australasian Physical and Engineering Sciences in Medicine - January 15, 2024 Category: Biomedical Engineering Source Type: research
Comparing fetal phantoms with surrogate organs in female phantoms during CT exposure of pregnant patients
In conclusion, while the female uterus can indicate fetal radiation dose if the fetus is outside the primary beam, it is unreliable when the fetus is within the primary beam. More reliable abdomen/pelvic organs were recommended. (Source: Australasian Physical and Engineering Sciences in Medicine)
Source: Australasian Physical and Engineering Sciences in Medicine - January 11, 2024 Category: Biomedical Engineering Source Type: research
Inter-fractional portability of deep learning models for lung target tracking on cine imaging acquired in MRI-guided radiotherapy
This study aims to evaluate how deep-learning (DL) models for target tracking that are trained on data from one fraction can be translated to subsequent fractions. Cine images were acquired for six patients treated on an MRI-guided radiotherapy platform (MRIdian, Viewray Inc.) with an onboard 0.35 T MRI scanner. Three DL models (U-net, attention U-net and nested U-net) for target tracking were trained using two training strategies: (1) uniform training using data obtained only from the first fraction with testing performed on data from subsequent fractions and (2) adaptive training in which training was updated each fracti...
Source: Australasian Physical and Engineering Sciences in Medicine - January 10, 2024 Category: Biomedical Engineering Source Type: research
Distributed visual positioning for surgical instrument tracking
AbstractIn clinical operations, it is crucial for surgeons to know the location of the surgical instrument. Traditional positioning systems have difficulty dealing with camera occlusion, marker occlusion, and environmental interference. To address these issues, we propose a distributed visual positioning system for surgical instrument tracking in surgery. First, we design the marker pattern with a black and white triangular grid and dot that can be adapted to various instrument surfaces and improve the marker location accuracy of the feature. The cross-points in the marker are the features that each feature has a unique ID...
Source: Australasian Physical and Engineering Sciences in Medicine - January 9, 2024 Category: Biomedical Engineering Source Type: research
A computed tomography radiomics-based model for predicting osteoporosis after breast cancer treatment
In conclusion, the clinical-radiomic predictive model may be used as an opportunistic screening tool for early identification of breast cancer survivors at high risk of CTIBL based on non-contrast CT images of the L1 vertebra, thereby facilitating early intervention for osteoporosis. (Source: Australasian Physical and Engineering Sciences in Medicine)
Source: Australasian Physical and Engineering Sciences in Medicine - January 8, 2024 Category: Biomedical Engineering Source Type: research
In Australia professional registration for qualified medical physicists should be mandated through the Australian Health Practitioner Regulation Agency (AHPRA)
(Source: Australasian Physical and Engineering Sciences in Medicine)
Source: Australasian Physical and Engineering Sciences in Medicine - January 2, 2024 Category: Biomedical Engineering Source Type: research
Prediction of SBRT response in liver cancer by combining original and delta cone-beam CT radiomics: a pilot study
This study aims to explore the feasibility of utilizing a combination of original and delta cone-beam CT (CBCT) radiomics for predicting treatment response in liver tumors undergoing stereotactic body radiation therapy (SBRT). A total of 49 patients are included in this study, with 36 receiving 5-fraction SBRT, 3 receiving 4-fraction SBRT, and 10 receiving 3-fraction SBRT. The CBCT and planning CT images from liver cancer patients who underwent SBRT are collected to extract overall 547 radiomics features. The CBCT features which are reproducible and interchangeable with pCT are selected for modeling analysis. The delta fea...
Source: Australasian Physical and Engineering Sciences in Medicine - January 2, 2024 Category: Biomedical Engineering Source Type: research
Flow-induced high frequency vascular wall vibrations in an arteriovenous fistula: a specific stimulus for stenosis development?
AbstractHemodialysis is the lifeline for nearly three million end stage renal disease patients worldwide. Native arteriovenous fistula (AVF) is the preferred vascular access, but 40% fail within 1 year. We recently demonstrated that AVFs harbour transitional flows and the goal of the present study was to investigate whether the associated high-frequency pressure fluctuations could promote vibrations within the vascular wall. We acquired MRI images and flow rates immediately after surgery in one patient and generated a 3D patient-specific model. High-fidelity fluid structure interaction simulations revealed the presence of ...
Source: Australasian Physical and Engineering Sciences in Medicine - December 29, 2023 Category: Biomedical Engineering Source Type: research
Development and validation of a gel wax phantom to evaluate geometric accuracy and measurement of a hyperechoic target diameter in diagnostic ultrasound imaging
This study aimed to develop a low-cost gel wax phantom with targets to determine the lateral and axial resolution and diameter of a hyperechoic target in an US scanner. The acoustic property (AP) of gel wax, which includes the speed of sound (cus), acoustic impedance (Z), and attenuation coefficient (µ), were determined for multiple transducers operating at 2.25, 5, 10, 15, and 30 MHz. These results were compared to the AP of soft tissue. Two polytetrafluoroethylene (PTFE) rectangular frames with holes separated by 5, 10, and 20 mm were constructed. Nylon filaments and stainless-steel disc (SS disc) (diameter = 16....
Source: Australasian Physical and Engineering Sciences in Medicine - December 27, 2023 Category: Biomedical Engineering Source Type: research
