Implementing a nurse-led screening clinic for symptom distress with community-based referral for cancer survivors: A feasibility study.

INTRODUCTION: This prospective, single-arm, pragmatic implementation study evaluated the feasibility of a nurse-led symptom-screening program embedded in routine oncology post-treatment outpatient clinics by assessing (1) the acceptance rate for symptom distress screening (SDS), (2) the prevalence of SDS cases, (3) the acceptance rate for community-based psychosocial support services, and (4) the effect of referred psychosocial support services on reducing symptom distress. METHODS: Using the modified Edmonton Symptom Assessment System (ESAS-r), we screened patients who recently completed cancer treatment. Patients screening positive for moderate-to-severe symptom distress were referred to a nurse-led community-based symptom-management program involving stepped-care symptom/psychosocial management interventions using a pre-defined triage system. Reassessments were conducted at 3-months and 9-months thereafter. The primary outcomes included SDS acceptance rate, SDS case prevalence, intervention acceptance rate, and ESAS-r score change over time. RESULTS: Overall, 2988/3742(80%) eligible patients consented to SDS, with 970(32%) reporting ≥1 ESAS-r symptom as moderate-to-severe (caseness). All cases received psychoeducational material, 673/970(69%) accepted psychosocial support service referrals. Among 328 patients completing both reassessments, ESAS-r scores improved significantly over time (p < 0.0001); 101(30.8%) of patients remained ESAS cases throughout the study, 112(34.1%) recovered at 3-month post-baseline, an additional 72(22%) recovered at 9-month post-baseline, while 43(12.2%) had resumed ESAS caseness at 9-month post-baseline. CONCLUSION: Nurse-led SDS programs with well-structured referral pathways to community-based services and continued monitoring are feasible and acceptable in cancer patients and may help in reducing symptom distress. We intend next to develop optimal strategies for SDS implementation and referral within routine cancer care services.

The Orthotic Effects of Different Functional Electrical Stimulation Protocols on Walking Performance in Individuals with Incomplete Spinal Cord Injury: A Case Series.

Background: Functional electrical stimulation (FES) of paralyzed muscles can facilitate walking after spinal cord injury (SCI). Objectives: To test the orthotic effects of different FES walking protocols on lower joint kinematics and walking speed. Methods: Three adults with incomplete SCI participated in this study. Their lower extremity motor scores and 10-meter walk test results were as follows: subject A: 50, 1.05 m/s, subject B: 44, 0.29 m/s, and subject C: 32, 0.27 m/s. Participants completed four conditions of over-ground walking including no FES and three bilateral FES-walking protocols as follows: multi-muscle stimulation (stimulation of quadriceps and gastrocnemius in the stance phase, and hamstring and tibialis anterior in the swing phase), drop foot (tibialis anterior stimulation), and flexor withdrawal (common peroneal nerve stimulation). The FES system obtained gait phase information from foot switches located under the individuals' heels. Three-dimensional kinematic analysis was undertaken to measure minimum toe clearance (MTC); ankle, knee, and hip range of motion (ROM); stride length; and stride speed. Results: Compared to no-FES walking, MTC increased during drop foot (all subjects), flexor withdrawal (subjects A and B), and multi-muscle stimulation (subjects B and C) protocols. A significant decrease in ankle ROM was seen with drop foot (all subjects), flexor withdrawal (subjects A), and multi-muscle stimulation (subjects A and C) protocols. Hip ROM increased with drop foot (subjects B and C), flexor withdrawal (subject B), and multi-muscle stimulation (subject C) protocols. Conclusion: Three FES walking protocols induced positive kinematic changes as indicated by increased MTC, decreased ankle ROM, and increased hip ROM during walking in subjects with incomplete SCI.

A viscoelastic model for the prediction of transcranial ultrasound propagation: application for the estimation of shear acoustic properties in the human skull.

A better understanding of ultrasound transmission through the human skull is fundamental to develop optimal imaging and therapeutic applications. In this study, we present global attenuation values and functions that correlate apparent density calculated from computed tomography scans to shear speed of sound. For this purpose, we used a model for sound propagation based on the viscoelastic wave equation (VWE) assuming isotropic conditions. The model was validated using a series of measurements with plates of different plastic materials and angles of incidence of 0°, 15° and 50°. The optimal functions for transcranial ultrasound propagation were established using the VWE, scan measurements of transcranial propagation with an angle of incidence of 40° and a genetic optimization algorithm. Ten (10) locations over three (3) skulls were used for ultrasound frequencies of 270 kHz and 836 kHz. Results with plastic materials demonstrated that the viscoelastic modeling predicted both longitudinal and shear propagation with an average (±s.d.) error of 9(±7)% of the wavelength in the predicted delay and an error of 6.7(±5)% in the estimation of transmitted power. Using the new optimal functions of speed of sound and global attenuation for the human skull, the proposed model predicted the transcranial ultrasound transmission for a frequency of 270 kHz with an expected error in the predicted delay of 5(±2.7)% of the wavelength. The sound propagation model predicted accurately the sound propagation regardless of either shear or longitudinal sound transmission dominated. For 836 kHz, the model predicted accurately in average with an error in the predicted delay of 17(±16)% of the wavelength. Results indicated the importance of the specificity of the information at a voxel level to better understand ultrasound transmission through the skull. These results and new model will be very valuable tools for the future development of transcranial applications of ultrasound therapy and imaging.

Design and validation of an MR-conditional robot for transcranial focused ultrasound surgery in infants.

PURPOSE: Current treatment of intraventricular hemorrhage (IVH) involves cerebral shunt placement or an invasive brain surgery. Magnetic resonance-guided focused ultrasound (MRgFUS) applied to the brains of pediatric patients presents an opportunity to treat IVH in a noninvasive manner, termed "incision-less surgery." Current clinical and research focused ultrasound systems lack the capability to perform neonatal transcranial surgeries due to either range of motion or dexterity requirements. A novel robotic system is proposed to position a focused ultrasound transducer accurately above the head of a neonatal patient inside an MRI machine to deliver the therapy. METHODS: A clinical Philips Sonalleve MRgFUS system was expanded to perform transcranial treatment. A five degree-of-freedom MR-conditional robot was designed and manufactured using MR compatible materials. The robot electronics and control were integrated into existing Philips electronics and software interfaces. The user commands the position of the robot with a graphical user interface, and is presented with real-time MR imaging of the patient throughout the surgery. The robot is validated through a series of experiments that characterize accuracy, signal-to-noise ratio degeneration of an MR image as a result of the robot, MR imaging artifacts generated by the robot, and the robot's ability to operate in a representative surgical environment inside an MR machine. RESULTS: Experimental results show the robot responds reliably within an MR environment, has achieved 0.59 ± 0.25 mm accuracy, does not produce severe MR-imaging artifacts, has a workspace providing sufficient coverage of a neonatal brain, and can manipulate a 5 kg payload. A full system demonstration shows these characteristics apply in an application environment. CONCLUSIONS: This paper presents a comprehensive look at the process of designing and validating a new robot from concept to implementation for use in an MR environment. An MR conditional robot has been designed and manufactured to design specifications. The system has demonstrated its feasibility as a platform for MRgFUS interventions for neonatal patients. The success of the system in experimental trials suggests that it is ready to be used for validation of the transcranial intervention in animal studies.

Is intrapartum translabial ultrasound examination painless?

OBJECTIVES: To find out whether intrapartum translabial ultrasound examination is painless by comparing pain score of ultrasound-based versus digital vaginal examination of foetal head station. METHODS: In 94 women carrying uncomplicated-term singleton pregnancies, labour progress was assessed by translabial ultrasound, followed immediately by conventional digital vaginal examination. Pain scores (0-10) using visual analogue pain scale were obtained for both examinations. Forty-eight and forty-six sets of data were obtained in first and second stage of labour, respectively. The difference in pain scores between digital vaginal examination and translabial ultrasound was analysed. RESULTS: The median pain score for translabial ultrasound was 0 (range 0-8), while that for vaginal examination was 4.5 (range 0-10), p < 0.05. There was no significant difference in pain scores between first and second stages of labour for translabial ultrasound (p = 0.123) and for vaginal examination (p = 0.680). The pain score for vaginal examination was higher than that of translabial ultrasound in 81.9%, similar in 13.8% and lower in 4.3% of cases. There was no statistically significant difference in pain scores obtained for digital vaginal examination by clinicians with different experience (p = 0.941). CONCLUSIONS: Intrapartum translabial ultrasound is generally better tolerated than digital vaginal examination for assessment of labour progress, making it an acceptable adjunctive assessment tool during labour.

Multi-frequency characterization of the speed of sound and attenuation coefficient for longitudinal transmission of freshly excised human skulls.

For medical applications of ultrasound inside the brain, it is necessary to understand the relationship between the apparent density of skull bone and its corresponding speed of sound and attenuation coefficient. Although there have been previous studies exploring this phenomenon, there is still a need to extend the measurements to cover more of the clinically relevant frequency range. The results of measurements of the longitudinal speed of sound and attenuation coefficient are presented for specimens of human calvaria. The study was performed for the frequencies of 0.27, 0.836, 1.402, 1.965 and 2.525 MHz. Specimens were obtained from fresh cadavers through a protocol with the Division of Anatomy of the University of Toronto. The protocol was approved by the Research Ethics Board of Sunnybrook Health Sciences Centre. The specimens were mounted in polycarbonate supports that were marked for stereoscopic positioning. Computer tomography (CT) scans of the skulls mounted on their supports were performed, and a three-dimensional skull surface was reconstructed. This surface was used to guide a positioning system to ensure the normal sound incidence of an acoustic signal. This signal was produced by a focused device with a diameter of 5 cm and a focal length of 10 cm. Measurements of delay in time of flight were carried out using a needle hydrophone. Measurements of effective transmitted energy were carried out using a radiation force method with a 10 µg resolution scale. Preliminary functions of speed of sound and attenuation coefficient, both of which are related to apparent density, were established using a multi-layer propagation model that takes into account speed of sound, density and thickness of the layer. An optimization process was executed from a large set of random functions and the best functions were chosen for those ones that closest reproduced the experimental observations. The final functions were obtained after a second pass of the optimization process was executed, but this time using a finite-difference time-difference solution of the Westervelt equation, which is more precise than the multi-layer model but much more time consuming for computation. For six of seven specimens, measurements were carried out on five locations on the calvaria, and for the other specimen three measurements were made. In total, measurements were carried out on 33 locations. Results indicated the presence of dispersion effects and that these effects are different according to the type of bone in the skull (cortical and trabecular). Additionally, both the speed of sound and attenuation showed dependence on the skull density that varied with the frequency. Using the optimal functions and the information of density from the CT scans, the average values (±s.d.) of the speed of sound for cortical bone were estimated to be 2384(± 130), 2471(± 90), 2504(± 120), 2327(± 90) and 2053(± 40) m s(-1) for the frequencies of 270, 836, 1402, 1965 and 2526 kHz, respectively. For trabecular bone, and in the same order of frequency values, the speeds of sound were 2140(± 130), 2300(± 100), 2219(± 200), 2133(± 130) and 1937(± 40) m s(-1), respectively. The average values of the attenuation coefficient for cortical bone were 33(± 9), 240(± 9) and 307(± 30) Np m(-1) for the frequencies of 270, 836, and 1402, respectively. For trabecular bone, and in the same order of frequency values, the average values of the attenuation coefficient were 34(± 13), 216(± 16) and 375(± 30) Np m(-1), respectively. For frequencies of 1.965 and 2.525 MHz, no measurable radiation force was detected with the setup used.

Posturographic measures in healthy young adults during quiet sitting in comparison with quiet standing.

Measures of postural steadiness - known as posturography - are commonly used for balance assessment during quiet standing. Although quiet sitting balance may be studied via posturography as well, this has not been done to date. As such, the purpose of this study was to characterize the posturography during quiet sitting in comparison with quiet standing and to provide a benchmark for future studies investigating differences in balance regulation and execution. Twelve young and healthy people agreed to quietly sit and stand on a force platform with their eyes open and closed. For each condition, one trial of 2 min was executed and the anterior-posterior, medial-lateral, and resultant distance fluctuations of the body's center of pressure (COP) were calculated. Finally, time-domain, frequency-domain, and stabilogram diffusion function (SDF) measures were identified and compared for all COP time series. The results consistently indicate that, for quiet sitting, the body sway size and velocity were smaller and the power-weighted average frequency larger than for quiet standing. Moreover, the SDF analysis revealed that quiet sitting shows fewer drifts over short time intervals, but also fewer controlled adjustments in the longer term to bring the system back to equilibrium. The observed differences can be partially explained by biomechanical and dynamic differences of the body portions that are in motion during quiet sitting and standing. The SDF analysis suggests, however, that also the balance control strategies are not identical. These findings may be especially useful for the assessment of sitting balance and the development of novel balance rehabilitation techniques and assistive devices.

Responses of the trunk to multidirectional perturbations during unsupported sitting in normal adults.

Understanding how the human body responds to unexpected force perturbations during quiet sitting is important to the science of motor behavior and the design of neuroprostheses for sitting posture. In this study, the performance characteristics of the neck and trunk in healthy individuals were assessed by measuring the kinematic responses to sudden, unexpected force perturbations applied to the thorax. Perturbations were applied in eight horizontal directions. It was hypothesized that displacement of the trunk, settling time and steady-state error would increase when the perturbation direction was diagonal (i.e., anterior-lateral or posterior-lateral) due to the increased complexity of asymmetrical muscle responses. Perturbation forces were applied manually. The neck and trunk responded in a synchronized manner in which all joints achieved peak displacement simultaneously then returned directly to equilibrium. Displacement in the direction of perturbation and perpendicular to the direction of perturbation were both significantly greater in response to diagonal perturbations (p<.001). The center of mass returned to equilibrium in 3.64±1.42 s after the onset of perturbation. Our results suggest that the trunk sometimes behaves like an underdamped oscillator and is not controlled by simple stiffness when subjected to loads of approximately 200 N. The results of this study are intended to be used to develop a neuroprosthesis for artificial control of trunk stability in individuals with spinal cord injury.

Postural reactions of the trunk muscles to multi-directional perturbations in sitting.

BACKGROUND: The dynamic role of the trunk musculature, with respect to stability, has not been fully explored to date. The purpose of this study was, using a transient and multi-directional perturbation, to: (1) quantify the tonic level of activity in the superficial trunk musculature prior to any perturbation; (2) quantify the phasic activity in those same muscles following application of a transient, horizontally directed load; and (3) quantify the direction-dependent behavior of this phasic response. METHODS: Twelve healthy individuals were perturbed during sitting via a chest harness in eight horizontal directions. Surface electromyograms were measured bilaterally from the abdominal (rectus abdominis, internal and external obliques) and back musculature (thoracic and lumbar erector spinae) to determine the tonic muscle activity prior to perturbation, and the phasic response following perturbation. A descriptive model was used to characterize the relationship between the phasic response of the muscles due to perturbation and the pulling direction. FINDINGS: Tonic activity in the trunk musculature in upright sitting is low, but still above resting levels by at about 1-3% of the MVC for the abdominal muscles, and 4-6% for the back muscles. Each trunk muscle also showed a direction-specific, phasic activation in response to perturbation, above these tonic levels of activation. This phasic activation was accurately modeled using a descriptive model for each muscle. INTERPRETATION: The obtained muscle activation level and the identified descriptive model will be applied in the design of a closed-loop controller for functional electrical stimulation.