Patient-Specific Polyvinyl Alcohol Phantoms for Applications in Minimally Invasive Surgery

In biomedical engineering, phantoms are physical models of known geometric and material composition that are used to replicate biological tissues. Phantoms are vital tools in the testing and development of novel minimally invasive devices, as they can simulate the conditions in which devices will be used. Clinically, phantoms are also highly useful as training tools for minimally invasive procedures, such as those performed in regional anaesthesia, and for patient-specific surgical planning. Despite their widespread utility, there are many limitations with current phantoms and their fabrication methods. Commercial phantoms are often prohibitively expensive and may not be compatible with certain imaging modalities, such as ultrasound. Much of the phantom literature is complicated or hard to follow, making it difficult for researchers to produce their own models and it is highly challenging to create anatomically realistic phantoms that replicate real patient pathologies. Therefore, the aim of this work is to address some of the challenges with current phantoms. Novel fabrication methods and frameworks are presented to enable the creation of phantoms that are suitable for use in both the development of novel devices and as clinical training tools, for applications in minimally invasive surgery. This includes regional anaesthesia, brain tumour resection, and percutaneous coronary interventions. In such procedures, imaging is of key importance, and the phantoms developed are demonstrated to be compatible across a range of modalities, including ultrasound, computed tomography, MRI, and photoacoustic imaging

Early child care and adiposity at kindergarten entry

The association between pre-school child care participation and markers of adiposity at kindergarten entry was examined using parent reported previous child care exposure and directly measured body mass index (BMI) and waist circumference (WC) of kindergarten children (N=201; boys=106, girls=95). It was hypothesized that kindergarten children with previous exposure to full-time non-parent child care (FNPC; \u3e20h/week) would have increased risk of overweight/obesity (BMI≥ 85th percentile) and high central adiposity (WC ≥80th percentile) compared to parent care (PC). The data suggest that there was no significant relationship between FNPC (n=112) and risk of overweight/obesity (OR=1.17, 95% CI=0.58-2.34, p=0.66) or central adiposity (OR=1.82, 95% CI=0.95-3.50, p=0.71). However, girls in the FNPC group had greater BMI (PC=15.3±1.6 kg/m2vs FNPC=16.1± 1.5 kg/m2; p=0.03) and WC (PC=51.7±4.1 cm vs FNPC=53.8±4.1 cm; p=0.02) values compared to PC. These differences were not found in boys. These findings suggest that girls exposed to non-parent care during early years may be vulnerable to increased adiposity

Contamination of histology biopsy specimen - a potential source of error for surgeons: a case report

Tissue contamination is a common occurrence in pathology, but surgeons are relatively unaware of this. We present the case of a 45-year-old man with Barrett's oesophagus, in which the histology of routine biopsies of an asymptomatic patient, were reported as 'carcinoma in situ'. Further biopsies were taken over a three month period but showed no evidence of malignancy. Tissue contamination or 'cross over' was identified as the likely cause of the abnormal result. This case report highlights the importance of the correlation of the clinical and histopathological findings and tissue contamination should be considered when both of these findings are not consistent

Direct Model-Based Inversion for Improved Freehand Optical Ultrasound Imaging

Optical ultrasound imaging uses light to both generate and detect pulse-echo ultrasound. Recently, we presented a fibre-optic optical ultrasound imaging probe comprising 64 sources and a single receiver that allowed for video-rate, freehand imaging. However, its low number of sources limited the image contrast when using Delay-and-Sum reconstruction. Here, we present an alternative image formation paradigm for optical ultrasound based on model-based inversion, where the low number of sources allows for direct (i.e., non-iterative) inversion under modest hardware requirements. The model accurately incorporates the aperture geometry, frequency-dependent source directivity, and performance variation across the aperture, thereby reducing image artefacts associated with these properties. The method achieves a 15 dB gain in image contrast compared to Delay-and-Sum, at a similar image formation time

Making ICU Research Happen: a Qualitative Descriptive Study About the Role of the Research Nurse in New Zealand Level III Intensive Care Units

This study explored the role of the research nurse in New Zealand (NZ) Level III intensive care units (ICU). Little was known about this role in NZ prior to this study. A qualitative, descriptive approach, using semi-structured interviews was used. The study was conducted in six Level III ICUs throughout NZ, who employed a research nurse. Interviews were conducted with research nurses (n = 11), the doctors they work with (principal investigators) (n = 6) and nurse managers (n = 6) for the ICUs, and the findings were triangulated. The views across all ICUs and stakeholders were generally similar, with differences only being in some operational areas. This study found that the primary role of the research nurse was trial management, where they coordinated all elements of trial conduct. Almost half of the research nurses were also involved in trial design through their positions on management committees. Research nurses also played a vital role in patient and trial advocacy, and they bridged the knowledge gap by bringing research to staff nurses, patients and their families. The issue of consent for clinical trials in the ICU setting was significant, as this was a process which research nurses were very involved in. Consenting patients was a shared responsibility of research nurses and doctors. There was a perception that research nurses were senior nurses, but not necessarily because of their role in research. The majority of research nurses reported to a nursing line manager, and also had an informal accountability to the principal investigator (PI). Research nurses and PIs worked closely in the pursuit of rigorous research for ICU patients, and research nurses were highly regarded by PIs. This study provides clarity about the research nurse‟s role and showcases their key contribution in ensuring that NZ ICUs undertake high quality research, thus contributing to potential improvements for future patients‟ outcomes

Friends and Families: a Study of the Quakers of the Earls Colne Area, 1655-1750

This study examines the economic and demographic characteristics of the 464 adult members of the Earls Colne, Halstead, and Coggeshall meetings of the Society of Friends in north-central Essex for the period 1655- 1750, and is an attempt to discover if this group differed from the general demographic pattern of the English population during the same period. Recent demographic historians have overlooked the non-conformist sects in their studies of population in Britain during these same years, but a search of the microfiche collection of the records of the English village of Earls Colne has yielded the birth and death records and the marriage certificates of the Quarterly and Monthly meetings of the Quakers in thir region. These documents allow the examination of demographic and economic patterns among this group of non-conformists for a hundred-year period.Histor