Heat-Mitigated Design and Lorentz Force-Based Steering of an MRI-Driven Microcatheter toward Minimally Invasive Surgery.

Catheters integrated with microcoils for electromagnetic steering under the high, uniform magnetic field within magnetic resonance (MR) scanners (3-7 Tesla) have enabled an alternative approach for active catheter operations. Achieving larger ranges of tip motion for Lorentz force-based steering have previously been dependent on using high power coupled with active cooling, bulkier catheter designs, or introducing additional microcoil sets along the catheter. This work proposes an alternative approach using a heat-mitigated design and actuation strategy for a magnetic resonance imaging (MRI)-driven microcatheter. A quad-configuration microcoil (QCM) design is introduced, allowing miniaturization of existing MRI-driven, Lorentz force-based catheters down to 1-mm diameters with minimal power consumption (0.44 W). Heating concerns are experimentally validated using noninvasive MRI thermometry. The Cosserat model is implemented within an MR scanner and results demonstrate a desired tip range up to 110° with 4° error. The QCM is used to validate the proposed model and power-optimized steering algorithm using an MRI-compatible neurovascular phantom and ex vivo kidney tissue. The power-optimized tip orientation controller conserves as much as 25% power regardless of the catheter's initial orientation. These results demonstrate the implementation of an MRI-driven, electromagnetic catheter steering platform for minimally invasive surgical applications without the need for camera feedback or manual advancement via guidewires. The incorporation of such system in clinics using the proposed design and actuation strategy can further improve the safety and reliability of future MRI-driven active catheter operations.

Patient satisfaction with private physiotherapy for musculoskeletal pain.

BACKGROUND: Despite emphasis on patient centred healthcare, healthcare professionals have been slow to use validated measurements of patient satisfaction in physiotherapy practice. The aim of this cross sectional survey was to measure patient satisfaction with private physiotherapy in Ireland, for patients with musculoskeletal pain, using a previously validated survey instrument. METHODS: A multidimensional patient satisfaction questionnaire 'PTOPS', which assesses patient satisfaction with outpatient physiotherapy treatment, was translated from American English to European English, and relevant demographic and global satisfaction items were included. This was then circulated to patients with musculoskeletal pain (n = 240) for anonymous completion and return to the research team. Data were analysed using the Statistical Package for the Social Sciences (SPSS, v.12). RESULTS: In total 55% (n = 131/240) of questionnaires were returned. Just over half of the respondents were male (53.4%, n = 70), with a mean age (SD) of 37.7 years (12.4), and had previous experience of physiotherapy (65.6%, n = 86). The most common site of musculoskeletal pain was spinal (51.5% n = 66). The mean (SD) number of treatments was 8.3 (8.3), at a mean total cost (SD) of 350.2 euros (322.8 euros). The 'PTOPS' questionnaire categorised and scored satisfaction items under four domains, Enhancer, Detractor, Location and Cost. The mean score (SD), optimum score, and scoring range for each domain were: 'Enhancer' 41.2 (3.8), 50, 10-50; 'Detractor' 19.4 (4.4), 10, 10-50; 'Location' 28.0 (4.1), 35, 7-35; 'Cost' 18.9 (2.8), 7, 7-35. "Overall satisfaction with physiotherapy experience" was scored on a five-point scale "excellent to poor", with a modal response of "Very Good" (42%; n = 55). CONCLUSION: This study measured patient satisfaction with private physiotherapy treatment for musculoskeletal pain in Ireland using a previously validated outcome measure and provides a template for future studies of this increasingly important topic. Results demonstrated high levels of satisfaction with all components of physiotherapy treatment, except cost, and provided valuable patient feedback regarding their physiotherapy treatment for musculoskeletal pain. Results can be used by physiotherapists to improve future patient experiences with a view to improving patient attendance and compliance with physiotherapy treatment protocols for patients with musculoskeletal pain.