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PubMed2005

Intraoperative monitoring of the recurrent laryngeal nerve using acoustic, free-run, and evoked electromyography.

The purpose of this study was to explore advantages and disadvantages of electrodes used for monitoring of the recurrent laryngeal nerve (RLN) and to determine the postoperative outcome in 135 patients. A pilot study examined 11 patients to compare the clinical performance of two commercially available recording electrodes and three stimulation electrodes for RLN neuromonitoring. After determining the most reliable and consistent stimulating/recording electrode combination, 124 patients were then monitored. In a total of 135 patients there was no permanent iatrogenic nerve damage to the RLN, although 2 patients developed transient vocal hoarseness that resolved shortly postoperatively. An initial "searching" current for evoked electromyography (EMG) was delivered at 0.7 mA and then decreased to a value of 0.35 mA, which reliably elicited RLN stimulation with a minimal incidence of false-positive results. The combination of auditory feedback from the mechanically elicited EMG and a control channel involving EMG monitoring of an additional peripheral muscle improved the detection of artifact and improved the clinical efficacy of intraoperative electromyography. A video camera showed the surgical manipulation on the EMG screen, allowing the neurophysiologist to correlate dissection with RLN status and location. Auditory responses from the nerve helped to determine the type of distress the RLN was encountering.

Acoustic Stimulation↗
PubMed2001

Continuous image and electrophysiological recording with real-time processing and control.

Collecting continuous video together with multichannel electrophysiological data and other experimental modalities requires high bandwidth and storage capacities, as well as accurate synchronization to detect correlations between different recorded events. Often, experiments are highly complex, with many variables requiring immediate analysis and feedback during the course of the experiment. In addition, output channels require real-time control with high time resolution. We have explored several approaches to a system that can perform the above functions. The design of our system considered a number of issues, including time intervals between control and acquisition events, longest continuous recording period, data transfer bottleneck considerations, file archiving and format, and real-time display and processing. To demonstrate the system, we describe an experiment for characterizing rapid evoked scattered light changes in neural tissue, in vivo, using simultaneous electronic image acquisition and electrophysiological recording.

Animals↗
PubMed1999

Reliability of student evaluations of voice therapy implications for theory and training.

This study examines reliability and the focus of attention of evaluations of voice therapy sessions. Therapy sessions were provided by 8 clinician-client pairs. For each pair, two 20-minute therapy sessions were evaluated by 50 undergraduate student raters and by 3 experienced clinicians. The goal of all therapy sessions was the modification of the frequency and type of voice onset. Raters evaluated each session using 12 behavioral and interpersonal criteria. Results indicated that (1) interrater reliability coefficients for each of the 12 criteria were moderately high to high, (2) the highest coefficients were found for ratings of the client, and (3) ratings of the client were found to be the most consistent across 2 sessions. Intrarater reliability was highest in ratings of quality, use of counseling, clarity and use of feedback, and amount of explanation by the clinician.

Adult↗
PubMed2002

Information sessions for outpatients referred to a hospital Nutrition and Dietetic Service for cholesterol lowering advice.

AIM: To assess the feasibility of recruiting outpatients referred for cholesterol lowering advice to attend a 1-h evening information session provided by a hospital dietitian and to evaluate the service. METHOD: A Cholesterol Information Session was held on one evening each month between April and September 2000. Patients referred to the Nutrition and Dietetic Service for cholesterol lowering advice were sent appointments for these sessions by post instead of a one-to-one daytime appointment with the dietitian. At the session, the dietitian explained what cholesterol is and gave advice about the healthy eating and lifestyle changes needed to control it. Video material and literature were used to support verbal information. Questions were encouraged throughout the session. RESULTS: Thirty-four patients were sent appointments. Twenty-seven (79%) attended, 10 of whom were accompanied by a spouse/partner/carer/family member. All patients who attended completed evaluation forms. There was a high level of satisfaction with the sessions. Twenty-six patients (96%) said they liked the way the session was run and found the advice and videos helpful. Twenty-five patients (93%) preferred the evening appointment to a day time one. Patients who attended with a spouse/partner/carer/family member indicated it was helpful to them and the accompanying person. Feedback through patient comments was positive. The seven patients (21%) who did not attend the sessions made contact with the dietetic service. CONCLUSION: As a result of the positive outcome of the evaluation, the Cholesterol Information Session is continuing as a service to patients. It provides a facility outside the usual hours of outpatient services and can readily accommodate accompanying people. The information session uses the group format, which may be applicable to other specialist areas of the Nutrition and Dietetic service in the future, such as diabetes management.

After-Hours Care↗
PubMed1996

Effects of a brief office-based intervention to facilitate diabetes dietary self-management.

OBJECTIVE: There is a pressing need for brief practical interventions that address diabetes management. Using a randomized design, we evaluated a medical office-based intervention focused on behavioral issues relevant to dietary self-management. RESEARCH DESIGN AND METHODS: There were 206 adult diabetes patients randomized to usual care or brief intervention, which consisted of touchscreen computer-assisted assessment to provide immediate feedback on key barriers to dietary self-management, and goal setting and problem-solving counseling for patients. Follow-up components to the single session intervention included phone calls and interactive video or videotape instruction as needed. RESULTS: Multivariate analyses of covariance revealed that the brief intervention produced greater improvements than usual care on a number of measures of dietary behavior (e.g., fewer calories from saturated fat, fewer high-fat eating habits and behaviors) at the 3-month follow-up. There were also significant differences favoring intervention on changes in serum cholesterol levels and patient satisfaction but not on glycosylated hemoglobin. The intervention effects were relatively robust across a variety of patient characteristics, the two participating physicians, and intervention staff members. CONCLUSIONS: If the long-term results are equally positive and generalize to other setting, this intervention could provide a prototype for a feasible cost-effective way to integrate patient views and behavioral management into office-based care for diabetes.

Adult↗
PubMed2003

Enduring impact of communication skills training: results of a 12-month follow-up.

The efficacy of a communication skills training programme was shown through a randomised trial. Oncologists (N=160) from 34 cancer centres were allocated to written feedback plus course; course alone; written feedback alone or control. Each clinician had 6 - 10 interviews with patients videotaped at baseline and 3 months postintervention. Analysis of videotapes revealed improvements in the communication skills of clinicians randomised to training (n=80) compared with others (n=80). A 12-month follow-up assessment is reported here. Robust Poisson conditional analyses of counts of changes in communication behaviours revealed no demonstrable attrition in those who had shown improvement previously, including fewer leading questions, appropriate use of focused and open-ended questions and responses to patient cues. Additional skills, not apparent at 3 months, were now evident; the estimated effect sizes corresponded to 81% fewer interruptions (P=0.001) and increased summarising of information to 38% (P=0.038). However, expressions of empathy (54%, P=0.001) declined. The overall results show that 12 - 15 months postintervention, clinicians had integrated key communication skills into clinical practice and were applying others. This is the first RCT to show an enduring effect of communication skills training with transfer into the clinic.

Adult↗
PubMed2002

On defining metrics for assessing laparoscopic surgical skills in a virtual training environment.

One of the key components of any training environment for surgical education is a method that can be used for assessing surgical skills. Traditionally, defining such a method has been difficult and based mainly on observations. However, through advances in modeling techniques and computer hardware and software, such methods can now be developed using combined visual and haptic rendering of a training scene. This paper presents some ideas on how metrics may be defined and used in the assessment of surgical skills in a virtual laparoscopic training environment.

Animals↗
PubMed1979

Knowledge of performance, skill level and performance on the balance beam.

Knowledge of performance (KP) using video-tape replay (VTR) was given to a group of girls aged 12--13, n = 8, learning to perform a beginning balance beam routine. A control group (n = 8) was taught utilizing conventional information feedback. Performance was assessed by three U.S. Federation Gymnastic judges after four weeks and again after six weeks. All S's in the experimental group were judged to be at the associative learning stage. The data were analyzed using a mixed repeated measures design with one between and one within subjects variables. A significant treatment effect (F = 48.7, alpha less than or equal to .01) and treatment by group interaction (F = 19.21, alpha less than or equal to .01) resulted. The experimental group was responsible for the bulk of the significance and it was therefore concluded th KP via VTP for S's in the associative learning stage was beneficial.

Adolescent↗
PubMed2000

Dynamic interaction between myogenic and TGF mechanisms in afferent arteriolar blood flow autoregulation.

The dynamic activity of afferent arteriolar diameter (AAD) and blood flow (AABF) responses to a rapid step increase in renal arterial pressure (100-148 mmHg) was examined in the kidneys of normal Sprague-Dawley rats (n = 11) before [tubuloglomerular feedback (TGF)-intact] and after interruption of distal tubular flow (TGF-independent). Utilizing the in vitro blood-perfused juxtamedullary nephron preparation, fluctuations in AAD and erythrocyte velocity were sampled by using analog-to-digital computerized conversion, video microscopy, image shearing, and fast-frame, slow-frame techniques. These assessments enabled dynamic characterization of the autonomous actions and collective interactions between the myogenic and TGF mechanisms at the level of the afferent arteriole. The TGF-intact and TGF-independent systems exhibited common initial (0-24 vs. 0-13 s, respectively) response slope kinetics (-0.53 vs. -0.47% DeltaAAD/s; respectively) yet different maximum vasoconstrictive magnitude (-11.28 +/- 0.1 vs. -7. 02 +/- 0.9% DeltaAAD; P < 0.05, respectively). The initial AABF responses similarly exhibited similar kinetics but differing magnitudes. In contrast, during the sustained pressure input (13-97 s), the maximum vasoconstrictor magnitude (-7.02 +/- 0.9% DeltaAAD) and kinetics (-0.01% DeltaAAD/s) of the TGF-independent system were markedly blunted whereas the TGF-intact system exhibited continued vasoconstriction with slower kinetics (-0.20% DeltaAAD/s) until a steady-state plateau was reached (-25.9 +/- 0.4% DeltaAAD). Thus the TGF mechanism plays a role in both direct mediation of vasoconstriction and in modulation of the myogenic response.

Animals↗
PubMed2004

Content-based adaptive spatio-temporal methods for MPEG repair.

Block loss and propagation error due to cell loss or missing packet information during the transmission over lossy networks can cause severe degradation of block and predictive-based video coding. Herein, new fast spatial and temporal methods are presented for block loss recovery. In the spatial algorithm, missing block recovery and edge extention are performed by pixel replacement based on range constraints imposed by surrounding neighborhood edge information and structure. In the temporal algorithm, an adaptive temporal correlation method is proposed for motion vector (MV) recovery. Parameters for the temporal correlation measurement are adaptively changed in accordance to surrounding edge information of a missing macroblock (MB). The temporal technique utilizes pixels in the reference frame as well as surrounding pixels of the lost block. Spatial motion compensation is applied after MV recovery when the reference frame does not have sufficient information for lost MB restoration. Simulations demonstrate that the proposed algorithms recover image information reliably using both spatial and temporal restoration. We compare the proposed algorithm with other procedures with consistently favorable results.

Algorithms↗
PubMed1988

The effect of infrahyoid-muscle tenotomy on orofacial motor activity in the rat.

The effects of disturbed proprioceptive feedback from the infrahyoid muscles on the control of chewing and drinking were studied in the unrestrained rat. Rats were trained to lick and to eat in a fixed body position in front of a video camera. After training, the left and right sternohyoid, omohyoid and sternothyroid muscles were cut close to the hyoid bone. EMG-wire electrodes were inserted into the superficial masseter, the anterior and posterior digastic and sternhyoid muscles. EMG-recordings were made at the third, the tenth and the eighteenth day after tenotomy. After about a week the cut ends of the muscles became encapsulated in connective tissue and began to reattach to the hyoid bone; in some animals the sternohyoid muscle reattached to the trachea. In the period before reattachment the mean cycle duration for chewing (but not for drinking) increased. After reattachment the mean cycle duration returned to control values. The contraction patterns after tenotomy were similar to those of the controls during chewing and drinking. The mean burst duration of the sternohyoid increased after tenotomy during chewing but not drinking; it decreased in the digastric muscles and did not change in the masseter.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2005

Mobile tele-echography: user interface design.

Ultrasound imaging allows the evaluation of the degree of emergency of a patient. However, in some instances, a well-trained sonographer is unavailable to perform such echography. To cope with this issue, the Mobile Tele-Echography Using an Ultralight Robot (OTELO) project aims to develop a fully integrated end-to-end mobile tele-echography system using an ultralight remote-controlled robot for population groups that are not served locally by medical experts. This paper focuses on the user interface of the OTELO system, consisting of the following parts: an ultrasound video transmission system providing real-time images of the scanned area, an audio/video conference to communicate with the paramedical assistant and with the patient, and a virtual-reality environment, providing visual and haptic feedback to the expert, while capturing the expert's hand movements. These movements are reproduced by the robot at the patient site while holding the ultrasound probe against the patient skin. In addition, the user interface includes an image processing facility for enhancing the received images and the possibility to include them into a database.

Algorithms↗
PubMedDate not supplied

Training of head control in the sitting and semi-prone positions.

The purpose of this study was to compare the semi-prone (SP) and sitting (SIT) training positions with respect to head control in children with cerebral palsy, before and after 5 weeks biofeedback training using a head position trainer (HPT). Four children were randomly assigned to each of two training groups: (a) SP on a prone board inclined 45 degrees above the horizontal and (b) SIT in their personal wheelchair and orthotic device. The HPT, secured to the child's head, controlled a video-cassette player, turning it off when the head deviated beyond 25 degrees from the vertical (termed an error). The time in error and the number of errors during test periods of 3 minutes, without feedback and completed in both the SP and the SIT positions, were determined immediately before and after, and at 16 weeks after training. The SIT trained group performed significantly better immediately post-training in three of four comparisons (P < 0.01), but the groups performed similarly in the other eight comparisons--four immediately pre-training and four at 16 weeks post-training (P > 0.05). Post-training scores for the total group (n = 8) were significantly improved over pre-training scores, regardless of the test position or the criterion measurement (P < 0.05). Biofeedback training with a HPT can be effective in either the SIT or the SP positions, with improvement lasting at least 16 weeks after training is discontinued.

Biofeedback, Psychology↗
PubMed1992

Purkinje cell complex and simple spike changes during a voluntary arm movement learning task in the monkey.

1. To evaluate the role of the cerebellum during improvement of voluntary motor performance over time, the discharge of 88 Purkinje cells in the intermediate and lateral cerebellum of two primates (Macaca mulatta) was investigated during a motor learning task involving visually guided arm movements. The animals were trained to move a draftsman's style manipulandum over a horizontally placed video screen. The animals were required to move a cursor from the start box to one of four target boxes by movement of the manipulandum. Errors were introduced into the movement by altering the visual feedback loop, changing the gain between the cursor movement and the hand movement. When a novel gain was presented over 100-200 movement trials, the animals adapted the movements to the new gain. The animals used a strategy of scaling the amplitude and velocity of the initial phase of the movement while keeping the time to peak velocity constant. 2. The learning paradigm consisted of an initial control phase with 35-100 trials at the gain of 1.0. The next 100-200 trials, the learning phase, were presented at one of four gains (0.6, 0.75, 1.5, 2.0). Lastly, a testing phase involved 80% of 100 trials at the learned gain and 20% of the trials randomly interspersed at the control gain of 1.0. An additional "distance control" was used in most experiments to control for the movement scaling associated with learning. In this series of movements using a gain of 1.0, the target box was placed at the distance and direction the hand would have to move in the adapted state. Two aspects of the kinematics were the same for the distance control and the movement at the learned gain: movement amplitude and time to peak velocity. There were, however, slight differences in the peak velocity attained. For gains < 1.0, the peak velocity of the learned task was 14-20% lower than the distance controls, and for gains > 1.0, it was 10-18% higher. 3. After implantation of chronic unit recording hardware, Purkinje cell simple and complex spike discharge was recorded extracellularly during the learning task. The cells were located primarily in the ipsilateral intermediate zone or nearby hemisphere of lobules V and VI. Simple and complex spike histograms, as well as averages of the hand displacement and velocity profiles, were calculated for each phase of the paradigm. To determine the time course of any changes, the learning trials were subdivided into three equal phases.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗
PubMed1991

Videoendoscopic evaluation of patients with dysphagia: an adjunct to the modified barium swallow.

The modified barium swallow is currently the most comprehensive, widely available, and easily interpreted technique for the evaluation of patients with dysphagia by the head and neck surgeon. However, it requires the facilities, personnel, and use of a radiology suite, a trained speech pathologist, and exposure of the patient to radiation. It would therefore be helpful to have an adjunctive, physician based, nonradiographic method of examination that could provide information similar to and possibly even more complete than that supplied by the modified barium swallow. Such an adjunctive method could help otolaryngologist-head and neck surgeons confronted by a new patient with swallowing difficulties to orient themselves to the nature and severity of the problem while waiting for the modified barium swallow to be scheduled, performed, and reviewed. It could also be a helpful tool for management of patients with cancer of the head and neck, whose swallowing function may change rapidly in the early postoperative period. In such cases, intervals between modified barium swallow examinations (dictated by concern over radiation exposure) may be too far apart to allow up-to-the-minute decisions on case management. Finally, some patients who may be too ill to travel to the radiology suite might benefit from a bedside procedure that would yield information about swallowing function similar to that provided by the modified barium swallow. Videoendoscopic evaluation of dysphagia (VEED) is a protocol I developed and have used regularly since 1984. Experience with this method of dysphagia evaluation has shown that it answers the needs outlined above. Its usefulness also goes beyond that of the modified barium swallow by providing a more detailed understanding of the component anatomic and functional deficits that comprise a given patient's swallowing problem, information about upper aerodigestive tract sensory deficits, and a means for visual feedback training of pharyngeal and laryngeal musculature. The protocol is reviewed here. Case reports illustrating the clinical usefulness of VEED as an adjunct to the modified barium swallow are also presented, and the relative strengths and weaknesses of VEED and the modified barium swallow are compared.

Aged↗
PubMed2005

Multi-sensory surgical support system incorporating, tactile, visual and auditory perception modalities.

The incorporation of novel broad band sensory modalities, integrating tactile technology, with visual and auditory signals into the evolution of the next generation of surgical robotic is likely to significantly enhance their utility and safety. In this paper considerations are made of a system, where tactile information together with visual and audio feedback are integrated into a multisensory surgical support platform. The tactile sensor system uses a piezoelectric transducer (PZT) system to evaluate the haptic properties of tissues. The spatial position of the sensor is tracked by a video camera, visualizing the location of the marker. Tactile information is additionally converted to an audio signal, to represent tissue properties in terms of a frequency/amplitude modulated signal. Representative data were obtained from biological tissues demonstrating that the technology developed has potential applications in virtual systems or robotic tele-medical care. In view of these technical developments, consideration is made as to whether visual audio and tactile modalities act as independent sources of information.

Hearing↗
PubMed2005

Optical computer recognition of facial expressions associated with stress induced by performance demands.

Application of computer vision to track changes in human facial expressions during long-duration spaceflight may be a useful way to unobtrusively detect the presence of stress during critical operations. To develop such an approach, we applied optical computer recognition (OCR) algorithms for detecting facial changes during performance while people experienced both low- and high-stressor performance demands. Workload and social feedback were used to vary performance stress in 60 healthy adults (29 men, 31 women; mean age 30 yr). High-stressor scenarios involved more difficult performance tasks, negative social feedback, and greater time pressure relative to low workload scenarios. Stress reactions were tracked using self-report ratings, salivary cortisol, and heart rate. Subjects also completed personality, mood, and alexithymia questionnaires. To bootstrap development of the OCR algorithm, we had a human observer, blind to stressor condition, identify the expressive elements of the face of people undergoing high- vs. low-stressor performance. Different sets of videos of subjects' faces during performance conditions were used for OCR algorithm training. Subjective ratings of stress, task difficulty, effort required, frustration, and negative mood were significantly increased during high-stressor performance bouts relative to low-stressor bouts (all p < 0.01). The OCR algorithm was refined to provide robust 3-d tracking of facial expressions during head movement. Movements of eyebrows and asymmetries in the mouth were extracted. These parameters are being used in a Hidden Markov model to identify high- and low-stressor conditions. Preliminary results suggest that an OCR algorithm using mouth and eyebrow regions has the potential to discriminate high- from low-stressor performance bouts in 75-88% of subjects. The validity of the workload paradigm to induce differential levels of stress in facial expressions was established. The paradigm also provided the basic stress-related facial expressions required to establish a prototypical OCR algorithm to detect such changes. Efforts are underway to further improve the OCR algorithm by adding facial touching and automating application of the deformable masks and OCR algorithms to video footage of the moving faces as a prelude to blind validation of the automated approach.

Adult↗