Recent advances in electronics miniaturization have led to the development of low-power, low-cost, point-of-care ultrasound scanners. Low-cost systems employing simple bi-level pulse generation devices need only utilize binary phase modulated coded excitations to significantly improve sensitivity; however the performance of complementary codes in the presence of nonlinear harmonic distortion has not been thoroughly investigated. Through simulation, it was found that nonlinear propagation media with little attenuative properties can significantly deteriorate the Peak Sidelobe Level (PSL) performance of complementary Golay coded pulse compression, resulting in PSL levels of -62 dB using nonlinear acoustics theory contrasted with -198 dB in the linear case.
View Article and Find Full Text PDFBackground: Low shear stress has been implicated in abdominal aortic aneurysm (AAA) expansion and clinical events. We tested the hypothesis that low shear stress in AAA at baseline is a marker of expansion rate and future aneurysm-related events.
Methods: Patients were imaged with computed tomography angiography at baseline and followed up every 6 months >24 months with ultrasound measurements of maximum diameter.
Sprouting angiogenesis is an essential vascularization mechanism consisting of sprouting and remodelling. The remodelling phase is driven by rearrangements of endothelial cells (ECs) within the post-sprouting vascular plexus. Prior work has uncovered how ECs polarize and migrate in response to flow-induced wall shear stress (WSS).
View Article and Find Full Text PDFDoxorubicin plays an integral role in the treatment of patients with diffuse large B-cell lymphoma (DLBCL) but can be associated with significant toxicity. Treatment guidelines of British Columbia (BC) Cancer recommend the substitution of etoposide for doxorubicin in standard-dose R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) (R-CEOP) for patients who have a contraindication to anthracyclines; however, it is unknown if this compromises treatment outcome. We identified all patients with newly diagnosed DLBCL who were treated in BC with curative intent with R-CEOP (n = 70) within the study period.
View Article and Find Full Text PDFBackground: Adjuvant treatment in early ovarian clear cell carcinoma (OCCC) is not yet standardized. The objective of this population-based study was to compare the outcome of patients with early OCCC treated with adjuvant chemotherapy versus chemoradiotherapy (chemoRT) and evaluate the association of adjuvant radiotherapy regimens (whole abdominal radiotherapy [WART] versus pelvic nodal radiotherapy [PRT]) with outcome.
Patients And Methods: Chart review was conducted to identify patients with stage I and II OCCC with complete information on staging.
High-grade serous carcinoma of uterine adnexa (HGSC) is the most frequent histotype of epithelial ovarian cancer and has a poor 5-year survival rate due to late-stage diagnosis and the poor efficacy of standard treatments. Novel biomarkers of cancer outcome are needed to identify new targetable pathways and improve personalized treatments. Cell-surface screening of 26 HGSC cell lines by high-throughput flow cytometry identified junctional adhesion molecule 1 (JAM-A, also known as F11R) as a potential biomarker.
View Article and Find Full Text PDFObjectives: To assess the cost effectiveness from a Canadian perspective of index patient germline BRCA testing and then, if positive, family members with subsequent risk-reducing surgery (RRS) in as yet unaffected mutation carriers compared with no testing and treatment of cancer when it develops.
Methods: A patient level simulation was developed comparing outcomes between two groups using Canadian data. Group 1: no mutation testing with treatment if cancer developed.
Microfluidic technologies are commonly used for the manipulation of red blood cell (RBC) suspensions and analyses of flow-mediated biomechanics. To enhance the performance of microfluidic devices, understanding the dynamics of the suspensions processed within is crucial. We report novel, to our knowledge, aspects of the spatiotemporal dynamics of RBC suspensions flowing through a typical microchannel at low Reynolds number.
View Article and Find Full Text PDFEur J Vasc Endovasc Surg
September 2020
Objective: To test whether aneurysm biomechanical ratio (ABR; a dimensionless ratio of wall stress and wall strength) can predict aneurysm related events.
Methods: In a prospective multicentre clinical study of 295 patients with an abdominal aortic aneurysm (AAA; diameter ≥ 40 mm), three dimensional reconstruction and computational biomechanical analyses were used to compute ABR at baseline. Participants were followed for at least two years and the primary end point was the composite of aneurysm rupture or repair.
Introduction: Low risk gestational trophoblastic neoplasia, WHO prognostic score of 0 to 6, is highly curable. There is no consensus on the optimal chemotherapy. Common regimens are q2wk actinomycin-D (ACT-D), weekly intramuscular methotrexate (MTX) or multi-day MTX.
View Article and Find Full Text PDFObjective: Patients with advanced low-grade serous carcinoma (LGSC) have poor long-term survival rates. As a rare histotype, there are uncertainties regarding the use of current therapies. Thus, we studied practice patterns and treatment outcomes as part of a national initiative to better understand and improve the care of women with advanced LGSC.
View Article and Find Full Text PDFBackground: Niraparib, an inhibitor of poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP), has been associated with significantly increased progression-free survival among patients with recurrent ovarian cancer after platinum-based chemotherapy, regardless of the presence or absence of mutations. The efficacy of niraparib in patients with newly diagnosed advanced ovarian cancer after a response to first-line platinum-based chemotherapy is unknown.
Methods: In this randomized, double-blind, phase 3 trial, we randomly assigned patients with newly diagnosed advanced ovarian cancer in a 2:1 ratio to receive niraparib or placebo once daily after a response to platinum-based chemotherapy.
Objective: Survival but not cure rates have improved for epithelial ovarian cancer (EOC), demonstrating the need for effective prevention. Targeted prevention in BRCA carriers by risk reducing surgery (RRS) prevents 80% of cases but incurs additional up-front costs, compensated for by the potential for long term savings from treatment avoidance. Does prevention represent value for money? In the absence of long-term data from prospective trials, determining the cost effectiveness of a prevention strategy requires economic modelling.
View Article and Find Full Text PDFThe landscape of genetic testing in ovarian cancer patients has changed dramatically in recent years. The therapeutic benefits of poly ADP-ribose polymerase (PARP) inhibitors in treatment of -related ovarian cancers has resulted in an increased demand and urgency for genetic testing results, while technological developments have led to widespread use of multi-gene cancer panels and development of tumour testing protocols. Traditional genetic counselling models are no longer sustainable and must evolve to match the rapid evolution of genetic testing technologies and developments in personalized medicine.
View Article and Find Full Text PDFBackground: There is a potential for direct model manufacturing of abdominal aortic aneurysm (AAA) using 3D printing technique for generating flexible semi-transparent prototypes. A patient-specific AAA model was manufactured using fused deposition modelling (FDM) 3D printing technology. A flexible, semi-transparent thermoplastic polyurethane (TPU), called Cheetah Water (produced by Ninjatek, USA), was used as the flexible, transparent material for model manufacture with a hydrophilic support structure 3D printed with polyvinyl alcohol (PVA).
View Article and Find Full Text PDFFifteen per cent of women with epithelial ovarian cancer possess inherited mutations in the BRCA genes. Knowledge of her BRCA status is important to her and her family. Poly(ADP-ribose) polymerase (PARP) inhibitors provide a new therapeutic option for her.
View Article and Find Full Text PDFBackground: Aortic valve disease increases velocity and changes the way blood enters the aorta. Over time, the biomechanical environment can cause aortic remodelling. We hypothesized that aortic geometry and wall stress would be different in patients with aortic valve disease compared with controls.
View Article and Find Full Text PDFBackground: A blood-mimicking fluid developed by Ramnarine et al. has been widely used in flow phantoms for ultrasound flow imaging research, and it has also been cited by IEC 61685 as a reference for making blood-mimicking fluid.However, the surfactant material Synperonic N in this blood-mimicking fluid recipe is phased out from the European market due to environmental issues.
View Article and Find Full Text PDFObjective: Our aim was to evaluate the population-based outcomes of stages I and II invasive ovarian mucinous carcinomas (MCs) treated with adjuvant platinum-based chemotherapy and abdominopelvic radiotherapy (XRT).
Methods: International Federation of Gynecology and Obstetrics stage I/II MC cases referred to the British Columbia Cancer Agency between 1984 and 2014 were reviewed. Chemotherapy (minimum of 3 cycles) and XRT were the institutional policy for stages IA/B (grade 2/3) and IC/II (any grade).
Answer questions and earn CME/CNE Fifteen percent of women with epithelial ovarian cancer have inherited mutations in the BRCA breast cancer susceptibility genes. Knowledge of her BRCA status has value both for the woman and for her family. A therapeutic benefit exists for the woman with cancer, because a new family of oral drugs, the poly ADP-ribose polymerase (PARP) inhibitors, has recently been approved, and these drugs have the greatest efficacy in women who carry the mutation.
View Article and Find Full Text PDFInflammation detected through the uptake of ultrasmall superparamagnetic particles of iron oxide (USPIO) on magnetic resonance imaging (MRI) and finite element (FE) modelling of tissue stress both hold potential in the assessment of abdominal aortic aneurysm (AAA) rupture risk. This study aimed to examine the spatial relationship between these two biomarkers. Patients (n = 50) > 40 years with AAA maximum diameters > = 40 mm underwent USPIO-enhanced MRI and computed tomography angiogram (CTA).
View Article and Find Full Text PDFMagn Reson Imaging
November 2017
Purpose: To develop finite element analysis (FEA) of magnetic resonance elastography (MRE) in the human thigh and investigate inter-individual variability of measurement of muscle mechanical properties.
Methods: Segmentation was performed on MRI datasets of the human thigh from 5 individuals and FEA models consisting of 12 muscles and surrounding tissue created. The same material properties were applied to each tissue type and a previously developed transient FEA method of simulating MRE using Abaqus was performed at 4 frequencies.