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[176] EFFECTS OF AGING ON MOTOR UNIT FIRING BEHAVIOR
Zeynep Erim, PhD; Carlo J. De Luca, PhD; Joseph F.
Jabre, MD
NeuroMuscular Research Center, Boston University,
Boston, MA 02215; Physical Medicine and Rehabilitation
Service, Boston VA Medical Center, Boston, MA 02130; email:
erim@bu.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #B829-RA)
PURPOSE--It is hypothesized that there is a change in the control of aged motor units to accommodate their altered mechanical and physiological properties. The knowledge of age-related alterations in the control of motor units will provide insight into the observed decline in neuromuscular performance in the elderly.
METHODOLOGY--The first dorsal inter osseous muscle was chosen to be studied in male subjects during voluntary abduction of the index finger. Electromyographic signals, detected via the quadrifillar needle electrode and the surface bipolar electrodes, were recorded along with the force generated by the muscle. The Precision Decomposition Technique was used to identify firing times of motor units.
PROGRESS--Data from 10 "young" (20-37 yrs) and 10 "elderly" (65-88 yrs) subjects have been analyzed and the results compiled.
RESULTS--Observations on data analyzed so far suggest a depression of the firing rate of motor units in the elderly as compared to the young. The phenomenon of onion skin observed in the young whereby motor units recruited earlier during increasing force have a higher average firing rate than motor units recruited later which have a lower firing rate is not observed in the elderly, in whom the firing rate plots of motor units "crossover." The highly correlated common fluctuations in the firing rates of concurrently active motor units in the young are not as correlated in the elderly. There are polyphasic and satellite motor unit action potentials observed in the elderly. Taken together, these observations suggest an altered control behavior of motor units in the elderly as compared to the young. Further testing of subjects and decomposition of data are in progress.
FUTURE PLANS--Further testing of subjects and analysis of data are in progress.
[177] MUSCLE STRENGTH AND FUNCTIONAL PERFORMANCE IN PARKINSON'S DISEASE: A PILOT STUDY
Thomas Mathews, MD; Roger M. Glaser, PhD; Thomas W.J.
Janssen, PhD; D. Drew Pringle, EdD; Kathy D. Zoerb, PAC;
Trudy L. Cortez, PAC, José W. Almeyda, BS; William P.
Couch, BS
VA Medical Center, Dayton, OH 45428; Institute for
Rehabilitation Research and Medicine, Wright State
University School of Medicine, Dayton, OH 45420;
Rehabilitation Institute of Ohio, Miami Valley Hospital,
Dayton, OH 45409; email: mathews.thomas@dayton.va.gov;
t.janssen@fbw.vu.nl;
dpringle@desire.wright.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Pilot Project #B2064-PA)
PURPOSE--Our goal was to obtain a general indication of the severity of disability of persons with Parkinson's disease (PD). Qualitative clinical rating scales, such as the Hoehn & Yahr scale (H&Y) and the Unified Parkinson's Disease Rating Scale (UPDRS), are typically used. However, more precise and quantitative measurements may be desirable for evaluating disease progression and the results of clinical interventions. The purpose of this 1-year study was to gain more insight into the different characteristics of muscular strength and force production in relation to functional performance of persons with PD, so as to improve validity of clinical evaluations. Specific objectives are to develop an quantitative and reliable method to evaluate upper- and lower-body voluntary isometric and isokinetic (concentric and eccentric) strength of persons with PD; to correlate muscle strength parameters to gait performance and daily activity level for those persons; and to correlate scores on conventional PD clinical rating scales with the quantitative measures obtained for muscle strength and functional performance.
METHODOLOGY--Sixteen persons with PD were recruited from outpatient services at the Dayton VAMC and clinically rated using the H&Y and the UPDRS while being off medication. The subjects then performed a foot-tapping test to determine motor speed of both feet, and a sit-stand-walk test (SSW) to study complex motor performance and postural control. Within 2 weeks, the subjects underwent muscle strength (upper- and lower-body, concentric/eccentric/isometric) testing on an isokinetic dynamometer, and hand-grip strength testing with a hand-held dynamometer. Additionally, on a separate day, each underwent gait analysis using a 3-D motion capture system. Also, during one typical weekday, heart rate and body movements were monitored to estimate activity level and functional performance during daily life.
PRELIMINARY RESULTS--Data from 12 subjects have been analyzed. The H&Y was strongly related to UPDRS (r=0.86). None of these clinical ratings were significantly related to the muscle strength variables, the SSW, or activity level during daily life, and only moderately related to self-selected walking velocity (r=-0.64, r=-0.56) and stride length (r=-0.65, r=-0.57) as measured in the gait analysis. More strongly related to walking velocity and SSW performance was quadriceps concentric muscle strength (r=0.72, r=-0.60, respectively). Activity level was not significantly related to any variable. These data indicate that clinical ratings may only be moderately related to functional performance variables, such as the SSW, activity level during daily life, and gait parameters, suggesting a need for additional objective muscle strength and functional performance tests. The evaluation of the those with PD may be improved by the addition of quantitative muscle strength testing and functional performance analysis to the currently used qualitative clinical ratings.
[178] QUANTITATIVE MEASUREMENT OF UPPER LIMB SPASTICITY: A PILOT STUDY
James W. Little, MD, PhD; Robert Price, MSME; Justus
Lehmann, MD
Spinal Cord Injury Service, Puget Sound Health Care
System, Seattle, WA 98108; Dept of Rehabilitation Medicine
University of Washington, Seattle, WA 98195; email:
JWL128@u.washington.edu;
pricer@u.washington.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Pilot Project #B2118-PA)
PURPOSE--A disabling aspect of central nervous system disease is spasticity, a velocity-dependent muscle hypertonus due to hyperactive stretch reflexes. This spasticity impairs self-care and mobility after spinal cord injury, multiple sclerosis, brain injury, and stroke. Clinical management of spasticity is often suboptimal in several ways: 1) impaired voluntary movement due to spasticity is difficult to distinguish from that due to weakness; 2) the development of spasticity cannot be prevented; 3) the relationship between spasticity and contracture is not well understood; and 4) spasticity treatments are often ineffective or too costly. A major hindrance to progress in these areas is lack of practical quantitative spasticity measures.
METHODOLOGY--In this study, we will develop a joint rotational device, patterned after the Lehmann-Price ankle device, for measuring spasticity during passive motion. We will also add two new measures to quantitate spasticity during active motion. We will then assess its test-retest reliability and validity in three groups of subjects: nondisabled controls, tetraplegic subjects with elbow extensor spasticity, and tetraplegic subjects with elbow flexor weakness. We expect to show that these new spasticity measures distinguish spastic tetraplegic subjects from controls and weak tetraplegic subjects.
The initial focus is to design an elbow joint rotational device that incorporates a computer-controlled torque motor for oscillating the elbow over 5° at varying frequencies from 3 to 12 Hz and that has sufficient torsional stiffness to avoid resonance effects in the frequency range of interest. The device includes transducers for monitoring torque and angular position during passive motion produced by the torque motor. Fourier analysis is applied to determine torque at the various applied frequencies and its phase relationship to displacement. The pathlength across oscillation frequency in the viscous stiffness and elastic stiffness plane is a reliable, valid measure of ankle spasticity, as shown by Lehmann and Price. In this study, we will assess reliability and validity of this pathlength measure for quantitating elbow spasticity. With the torque motor disengaged, two additional measures are derived to quantitate spasticity during active elbow movements.
FUTURE PLANS/IMPLICATIONS--This study undertakes to develop reliable, valid measures of elbow spasticity that can be used to guide clinical management with physical modalities, medications, and blocks.
[179] SIMPLE TWO-JOINT SYNERGY IN INDIVIDUALS WITH DOWN SYNDROME
Alexander S. Aruin, PhD; Gil Almeida, PhD; Mark L.
Latash, PhD
Rehabilitation Foundation Inc. Wheaton, IL, 60189;
Department of Physical Medicine and Rehabilitation, Rush
University, Chicago IL 60612; University of Campinas,
Campinas, San Paulo, Brazil; Pennsylvania State University,
PA 16802; email: aruin@rfi.org
Sponsor: The Down's Syndrome Research Fund, Chicago, IL, 60642
PURPOSE--Redundancy of motor control system is an important feature that the central nervous system successfully uses, based on priorities presently unknown. Motor patterns reflecting these priorities may be different in unimpaired adults and impaired individuals with changed biomechanics of the body (amputation), changed reflexes (spasticity), impaired decision making (Down syndrome), impaired preprogramming (Parkinson's disease), and so forth. The aim of this study was to investigate the organization of motor patterns in individuals with Down syndrome.
METHODOLOGY--Six individuals with Down syndrome and six age- and gender-matched controls sat comfortably in a chair, placed their right upper arm on an adjustable horizontal surface, and performed discrete elbow or wrist, flexion or extension movements in a sagittal plane under the instruction to move one of the joints as fast as possible. The hand was either pronated or supinated. The EMG activity of biceps, lateral head of triceps, flexor carpi radialis and extensor carpi ulnaris longus, as well as wrist and elbow joint angle changes in a sagittal plane, were recorded.
RESULTS--Control subjects and subjects with Down syndrome demonstrated qualitatively different EMG patterns in the flexor/extensor muscle pairs acting at the focal and postural joints when the instruction required moving only one joint (focal) of a two-joint limb segment. Controls use alternating, phasic bursts of muscle activation, apparently leading to a sequence of alternating flexion and extension torques around the joint. Down syndrome individuals use co-contraction of muscles acting at the postural joint, thus increasing its stiffness and decreasing its deviations in response to perturbations irrespective of their direction (pronation or supination). The co-contraction strategy apparently allows persons with Down syndrome to achieve satisfactory control over arm movements, although it is also likely to contribute to the general impression of clumsiness of their movements. The difference in the organization of the investigated simple synergy between control subjects and individuals with Down syndrome is likely to be secondary (adaptive) to the impairment in the ability of persons with Down syndrome to make quick accurate decisions.
FUTURE PLANS--It is quite possible that some atypical motor patterns, that may look "clumsy," have been elaborated by the central nervous system of the individual with Down syndrome based on its current state and on the everyday experience with frequently occurring unexpected changes in motor tasks and movement conditions. Practice of movements in friendly, predictable laboratory conditions may lift some of the restrictions self-imposed by the central nervous system of the individual with Down syndrome and lead to more "normal-looking" movement patterns.
[180] SENSITIVITY AND SPECIFICITY OF A CLINICAL EXAMINATION OF SWALLOWING
Robert T. Wertz, PhD; Gary H. McCullough, PhD; John C.
Rosenbek, PhD
Audiology and Speech Pathology, VA Medical Center,
Nashville, TN 37212; Department of Speech Pathology and
Audiology, University of Tennessee, Knoxville, TN 37996;
Audiology and Speech Pathology, VA Medical Center, Madison,
WI 53705; email: wertz.robert_t.@nashville.va.gov
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #C2113-RA)
PURPOSE--The objective of this investigation is to develop a sensitive and specific clinical/bedside swallowing examination by testing the sensitivity and specificity of clinical/bedside appraisal procedures for dysphagia. We seek answers to two primary research questions: What is the sensitivity of a clinical/bedside examination for detecting dysphagia? What is the specificity of a clinical/bedside examination in the evaluation of dysphagia? Dysphagia is defined as the presence of bolus penetration/aspiration into the laryngeal vestibule during swallowing and/or the presence of a delayed initiation of swallowing.
METHODOLOGY--Subjects will be 180 clients in the VA Medical Centers in Nashville and Madison who have suffered a recent stroke prior to the time of examination. Each subject will receive a clinical/bedside swallowing examination and be rated for the presence of penetration/aspiration and/or delayed swallowing. A videofluoroscopic examination of swallowing will be conducted on each subject, and the presence of penetration/aspiration and/or delayed swallowing will be rated. Using the videofluoroscopic examination results as the gold standard for the presence of dysphagia, signal detection analysis will be conducted to determine the sensitivity and specificity of the clinical/bedside swallowing examination.
PROGRESS--The investigation will be initiated October 1997.
[181] EFFECTS OF AGE ON OROPHARYNGEAL SWALLOWING
JoAnne Robbins, PhD; Kimberly A.Chignell, MS; Gail
Dengel, MS; Brian Goodman, PhD; Jackie Hind, MS; Todd
Kennell, MD; Ross Levine, MD; Jennifer Wood, MS
William S. Middleton Memorial Veterans Hospital,
Madison, WI 53705; email: jrobbin2@facstaff.wisc.edu
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #E727-2RA)
PURPOSE--The long-term objective of this work is to increase understanding of the effects of aging on swallowing physiology in an effort to advance the diagnosis and treatment of swallowing disorders in age-related disease. The short-term aims of this project were to establish a normative database of movement parameters comprising salient features of oropharyngeal swallowing in conjunction with structural brain quantification throughout the adult age interval of 45 to 95 years and to further develop a pressure transducer, designed to measure tongue strength during swallowing.
PROGRESS--We are grateful to Kay Elemetrics who supported our efforts to modify aspects of their Swallowing Workstation, thereby resulting in our intraoral pressure measuring instrument. This is comprised of a thin strip of pressure-sensitive air-filled bulbs attached to the midsaggital line of the hard palate. The three pressure bulbs measure tongue strength simultaneously at anterior, mid, and posterior palate. Pressure from each bulb is transduced and recorded on the Workstation and linked with video data in order to facilitate understanding of amplitude by time relationships as they impact bolus transfer during swallowing. Prior to achieving the database of swallowing parameters, it was necessary to test the new instrumentation in order to determine the effect of its presence on swallowing physiology.
RESULTS--Principle components analysis of the submental EMG recordings of swallowing in bulb-in and bulb-out conditions indicated no significant systematic differences between conditions. The absence of a bulb condition effect indicates that swallowing physiology with the intra-oral pressure measuring instrument in place is similar to normal swallowing. We interpreted these findings as a green light to proceed with the new instrumentation as an integral part of our methodology. Significant differences in the EMG signal were found, however, for bolus viscosity (liquid/semi-solid) and age. Older subjects tended to have reduced EMG amplitude and a smaller range of phase shifts relative to their young counterparts.
While instrumentation development was underway, we used the Iowa Oral Performance Instrument (IOPI), a single air-filled pressure-sensitive bulb, to obtain maximum lingual pressures during isometric and saliva swallows in 15 old control, and 25 stroke, subjects. Performance on the isometric task did not distinguish control from stroke groups, nor did it differentiate stroke subjects from each other by site of lesion. However, stroke subjects showed a trend toward reduced swallowing pressures at the blade position (p=0.07). Also, stroke subjects who generated lower isometric pressures tended to have slower oral transit duration on videofluoroscopy.
Currently, we have collected multiple levels of data, including isometric and swallowing pressures, videofluoroscopic swallows, and magnetic resonance images (MRI) of the brain and the tongue on 51 of our intended 100 nonimpaired control subjects, stratified by age (45-95 years) and by gender. Preliminary analysis of six of the 45-year-olds and six of the 75-year-old controls reveals differences in swallowing duration, pressure generation, and clearance of material from the upper aerodigestive tract. Gender differences also are found in biomechanics of the volitional initial portion of the oropharyngeal swallow as well as for tongue volume as measured by the MRI. We shall continue data collection and analysis for the normative age- and gender-stratified swallowing database. It is of interest that several of our older controls (age>75) demonstrated aspiration of thin liquids during the study protocol. How this swallowing outcome relates to lingual pressures, timing, lingual volume, and central nervous system changes (the latter two variables measured with MRI) is currently under study.
Another aspect of our research is to apply the same instrumentation and protocol to stroke patients, with the intent of comparing physiologic and functional outcomes with those of the old controls. Therefore, we have collected analogous data on eight stroke patients, to date, for comparison to their age-matched controls.
Finally, this project permitted imaging of the esophagus on seven young and four old controls. Maximum distention of the UES, LES, and at 5 cm above the LES was measured, and speed from the upper esophagus to the LES for the head and tail of the bolus was analyzed. None of the anatomical or physiological parameters studied were significantly different between the two groups, indicating that the esophagrams of nonimpaired elders should appear similar to those of young adults, and abnormalities obtained from esophagrams most likely indicate specific pathologies in the elderly that must be carefully addressed.
FUTURE PLANS--In future, we intend to complete data collection and analysis for the normative age-stratified swallowing database that will improve clinical ability to differentiate pathologic from simple age-related changes in swallowing. Along with brain and lingual MRI analysis, this effort will elucidate underlying mechanisms in that central and peripheral nervous system contributions to changes in swallowing function with nonimpaired aging and with age-related disease will be determined.
We shall also pilot test a program in which old nonimpaired individuals who demonstrate reduced tongue volume (as determined by measuring volume on MRI) and perform on the lower end of the normal range for swallowing function in terms of strength (using our new intra-oral pressure instrument and the Kay Workstation), participate in an 8-wk lingual resistance exercise program.
[182] BIOMECHANICS AND SENSORY INPUT OF SWALLOW AFTER HEAD AND NECK CANCER
Jerilyn A. Logemann, PhD
Northwestern University, Communication Sciences and
Disorders, Evanston, IL 60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--This project examines the biomechanical effects of head and neck treatment on swallowing function and on the individual's ability to exert voluntary control over specific aspects of the swallow as well as the impact of varying bolus flavor. A biomechanical analysis will enable us to define the changes in muscle pull created by head and neck surgical procedures and to develop more effective swallow interventions, including surgical reconstruction.
METHODOLOGY--Videofluoroscopic (VFS) swallowing studies of persons under treatment for head and neck cancer, collected 3 points in time post treatment, will be quantified temporally and biomechanically to identify the ways in which voluntary maneuvers and postures as well as heightened sensory input from bolus flavors impact the swallow, as compared to normal age- and gender-matched controls.
PROGRESS--Over the last 15 mo, we have established approval for use of human subjects at participating institutions, and trained clinicians at those institutions in the proper instruction, administration, and assessment of adequacy of postures and maneuvers. We have recruited head and neck cancer subjects and age- and gender-matched controls.
FUTURE PLANS--We seek to complete a study of the effect of a sour-flavored bolus in head and neck cancer subjects and to continue recruitment.
[183] LONG-TERM SURVIVORS OF HEAD AND NECK CANCER
Jerilyn A. Logemann, PhD
Northwestern University, Communication Sciences and
Disorders, Evanston, IL 60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--Our first hypothesis based on pilot data is that treated head and neck cancer subjects continue to suffer significant functional deficits long after treatment has been completed, and that the exact nature of these deficits will vary, based on the original tumor site and stage, and nature of treatment (surgery and/or radiotherapy). A second objective of this project is to evaluate the effects of a specific intervention strategy on subject function. Our third objective is to determine whether the gains are maintained long term. A fourth objective is to define the cost of the intervention proposed and the cost impact of the intervention, such as a reduction of the need for expensive prepared feedings, decreased incidence of hospitalization for pneumonias that may be aspiration-related or for depression related disorders due to speech and swallowing problems, and changes in other health care needs. A fifth and final objective of this proposal is to determine whether it is possible to predict from baseline measures, and disease stage and treatment variables, those subjects who will benefit most from the intervention.
METHODOLOGY--Data collection begins with a baseline collection period on 300 head and neck cancer subjects at least 1-year post treatment, after which we enter into the intervention stage of the protocol any subject who is not eating a full range of diet consistencies (i.e., liquid, paste and masticated materials) because of a swallowing disorder, or whose oropharyngeal swallow efficiency is 30 or less on any food consistency, randomizing them to early intervention (group A) or delayed intervention (group B). At the end of the 4-mo intervention period for Group A, all subjects will be retested and the change over the 4-mo period measured. After retesting of function, subjects in Group B will begin their 4-mo intervention protocol, while Group A will receive no intervention. At the end of the second 4-mo period, both groups will again be tested to identify the effects of intervention in B and the carry-over in A.
PROGRESS--Over the last 15 mo, we have recruited head and neck cancer subjects, sending letters to medical oncologists, radiation oncologists, otolaryngologist/head and neck surgeons, and speech-language pathologists throughout northern Illinois and Indiana. We have begun to get phone calls from these individuals regarding the project and referral of subjects.
We have completed an analysis of oral and oropharyngeal cancer subjects who received swallowing and speech therapy of various types. We examined the effectiveness of range of motion exercises versus a general therapy program and found that those subjects who had range of motion exercises were demonstrating significant improvements in both speech understandability and swallowing efficiency.
FUTURE PLANS--We seek to accrue head and neck cancer subjects and follow them for a year and to complete data reduction on these 150 subjects.
[184] THE EFFECTS OF RADIOTHERAPY/CHEMOTHERAPY ON VOICE, SPEECH, AND SWALLOWING FUNCTION
Bharat B. Mittal, MD; Jerilyn A. Logemann, PhD; Merrill
Kies, MD
Department of Radiology/Oncology, Northwestern Memorial
Hospital, Chicago, IL 60611; Northwestern University,
Communication Sciences and Disorders, Evanston, IL
60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--This project proposes to define the effects of organ preservation protocols involving high dose radiotherapy (5,000+ cGy) with or without chemotherapy in 300 persons with oral, laryngeal, and pharyngeal cancer (previously untreated Stages II to IV disease) and to measure the effectiveness of swallow maneuvers in improving the swallow. Each individual's response to swallow maneuvers will be defined.
METHODOLOGY--Each subject will be followed for 12 mo after treatment completion. All will be studied pretreatment, and at 1, 3, 6, and 12 mo post completion of chemoradiotherapy. At each of these data collection points, each will receive a videofluoroscopic assessment of swallowing, a voice recording for acoustic analysis, and a speech analysis for understandability and articulatory production.
PROGRESS--Over the past 15 mo we have established approval for use of human subjects at participating institutions and trained clinicians at those institutions in the study protocol; and recruited head and neck cancer subjects.
RESULTS--Results continue to show a severe effect of combined high dose radiation and chemotherapy to the functions of laryngeal elevation and tongue-base/pharyngeal wall contraction. The combination of high-dose radiotherapy and chemotherapy appears to have a more devastating effect on swallowing than radiotherapy without concurrent chemotherapy. However, these are very early results and must be corroborated with larger subject numbers.
FUTURE PLANS--We seek to recruit 75 subjects and follow them for a year to complete data reduction on them, and to continue recruitment of head and neck cancer subjects.
[185] THE EFFECTS OF SURGICAL INTERVENTION ON SPEECH AND SWALLOWING FUNCTION IN PERSONS WITH RECURRENT/RESIDUAL DISEASE
Barbara Roa Pauloski, PhD; Jerilyn A. Logemann,
PhD
Northwestern University, Communication Sciences and
Disorders, Evanston, IL 60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--Changes in patterns of care over the past 5 years have resulted in the treatment of persons with oral and oropharyngeal cancer with radiation only or radiation and chemotherapy who would have previously received surgical intervention. It is expected that a number of these individuals will present with residual or recurrent disease for which surgery will be required for cancer control, and they may face significant functional impairment in the areas of speech and swallowing after salvage surgery. This study will examine the functional impairments and recovery of function experienced by this group over a 12-mo period after surgery.
METHODOLOGY--Each subject will be followed 12 mo postoperatively. All will be studied preoperatively, and at 1, 3, 6, and 12 mo posttreatment. At each of these data collection points, each subject will receive a videofluoroscopic assessment of swallowing and speech, an articulation test, and recording of conversational speech for later intelligibility rating.
PROGRESS--Over the last 15 mo, we have established approval for use of human subjects at participating institutions, and trained clinicians at those institutions in the proper instruction, administration, and assessment of adequacy of postures and maneuvers. We have recruited head and neck cancer subjects, and surveyed participants concerning changes in the pattern of care for recurrent subjects. We have modified the study protocol to include four groups of subjects, depending upon the combination of primary and salvage treatment, either of which may be radiotherapy, chemotherapy, or surgery.
FUTURE PLANS--We seek to reconceptualize the study questions for the new subject populations, to evaluate the revised protocol for accruals, retention, and potential for early stopping, and to continue recruitment of head and neck cancer patients.
[186] HEAD AND NECK CANCER: QUALITY OF LIFE, PERFORMANCE, AND PATIENTS' PRIORITIES
Marcy List, PhD; Jerilyn A. Logemann, PhD
University of Chicago, Cancer Research Center, Chicago,
IL 60637; Northwestern University, Communication Sciences
and Disorders, Evanston, IL 60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--The specific aims of the project are as follows: a) to determine rate and degree of recovery of function, mood, and overall quality of life by group (site, treatment) and time since treatment; to identify times of greatest difficulty for subjects. b) to evaluate subjects' priorities with respect to potential disease and treatment sequelae; to determine whether these rankings change over time as subjects experience effects of disease and treatment; and to determine the relationship between priority rankings and actual function. c) to compare the priorities of subjects with head and neck cancer to nonimpaired controls.
METHODOLOGY--A total of 500 head and neck cancer subjects representing four treatment types will be assessed at four points in time, pretreatment, and at 3, 6, and 12 mo posttreatment. The assessment will consist of the PSS-HN (Performance Status Scale for Head and Neck Cancer), the FACT-HN (Functional Assessment of Cancer Therapy Scale-Head and Neck), the subject's Priorities Ranking Scale, as well as the collection of relevant medical, personal, and social demographic data.
PROGRESS--Over the last 15 mo, we have established approval for use of human subjects at participating institutions, and trained clinicians at those institutions in the proper instruction, administration, and assessment of adequacy of postures and maneuvers. We have recruited head and neck cancer subjects.
FUTURE PLANS--Data collection will continue, and we will work with speech-language pathologists to identify and resolve any issues that interfere with timely, accurate collection. A significant increase in accrual is expected when IRB approvals have been obtained for all participating institutions. As head and neck cancer subjects are more rapidly accrued, we will begin enrollment of the control group.
[187] THE EFFECTS OF SURGICAL RECONSTRUCTION ON SPEECH AND SWALLOWING
Fred McConnel, MD; Jerilyn A. Logemann, PhD
Southern Ear, Nose, and Throat, Lawrenceville, GA 30245;
Northwestern University, Communication Sciences and
Disorders, Evanston, IL 60208-3540
Sponsor: National Institutes of Health, National Cancer Institute, Bethesda, MD 20892
PURPOSE--This study examines the effects of surgical reconstruction for oropharyngeal cancer as a first line rehabilitation strategy for persons with oral cancer. It is our hypothesis that particular surgical reconstruction can facilitate speech and swallowing or cause a further decrement in function. This project will follow 8 groups of surgically treated oral cancer subjects to examine the effects of surgical reconstruction on early and late functional outcomes of speech and swallowing.
METHODOLOGY--Each subject will be followed for 3 months postoperatively. All will be studied preoperatively, and at 1 and 3 mo posthealing. Those reconstructed with flaps designated as sensate will receive an additional assessment at 12 mo posthealing. At each of these data collection points, each subject will receive a videofluoroscopic assessment of swallowing and speech, an articulation test, and recording of conversational speech for later intelligibility rating.
PROGRESS--Over the last 15 mo, we have established approval for use of human subjects at participating institutions, and trained clinicians at those institutions in the proper instruction, administration, and assessment of adequacy of postures and maneuvers. We have recruited head and neck cancer subjects.
RESULTS--Results showed that irradiated subjects had significantly reduced oral and pharyngeal swallowing performance, while speech performance was not impaired.
FUTURE PLANS--We seek to add three institutions where the surgeons specialize in sensate flap reconstruction, and to continue accrual of head and neck cancer subjects.
[188] 3-D CONTOUR TRACKING OF PHARYNGEAL BOLUS MOVEMENT USING A KNOWLEDGE-BASED SNAKE SEARCH ALGORITHM
Michael W. Chang, MD, PhD; Eugene Lin, MS; Jenq-Neng
Hwang, PhD
Department of Rehabilitation Medicine, School of
Medicine and Department of Electrical Engineering, College
of Engineering, University of Washington, Seattle, WA 98195;
email: mwc@u.washington.edu
Sponsor: The Whitaker Foundation, Rosslyn, VA 22209
PURPOSE--Videofluorography (VFG) of the pharyngeal phase of swallowing using a barium-mixed bolus is in wide clinical use for assessing patients with swallowing disorders. VFG is usually done with both lateral (LA) and anterior-posterior (AP) views, most commonly in two separate sittings. It is important but tedious to reconstruct a real-time, three-dimensional (3-D) view of pharyngeal bolus evolution from these LA and AP video images. We applied a knowledge-based Snake search algorithm to semiautomate the contour tracking and reconstruction of these VFG images. 3-D evolution of the pharyngeal bolus can then be accurately and efficiently visualized.
METHODOLOGY--VFG of pharyngeal bolus transport in control subjects was recorded using barium-mixed boluses with combinations of three bolus consistencies (185, 5,000, 45,000 centi-poise (cp)), three bolus volumes (5, 10, and 20 cc), and three head positions (20° flexion, neutral, and 20° extension). VFG of a total of 16 barium swallows were recorded for each subject (8 in LA, 8 in AP). The resulting LA and AP video images were digitally captured and matched frame-by-frame on a Power Mac computer. A knowledge-based Snake search algorithm was used to generate points to satisfy both internal (i.e., smoothness) and external (i.e., boundary fitting) constraints. Using the points generated from the LA and AP video images, we traced the 3-D bolus movement at each time instant, assuming elliptic geometry of the cross-section area of the pharynx. By concatenating the 3-D images for each time instant, we developed a 3-D movie representing pharyngeal bolus movement.
PROGRESS--We have so far studied seven controls with normal swallow in pharyngeal phase.
PRELIMINARY RESULTS--VFGs of pharyngeal swallowing (viscosity: 185 cp, head position: neutral) in a control were analyzed with three bolus volumes (5, 10, 20 cc). Mean errors of the Snake algorithm were estimated to be 1.3 mm (in LA views) and 2.1 mm (in AP views) for all three volumes with respect to manually traced bolus boundaries. Bolus front and tail velocities were calculated from the original LA images and compared with those generated from the Snake search algorithm. Mean errors in bolus velocity calculation for all three bolus volumes were 5.8 cm/s (front), and 2.6 cm/s (tail).
IMPLICATIONS--3-D pharyngeal bolus movement can be traced both efficiently and accurately using a knowledge-based Snake search algorithm. Video images from standard clinical VFG studies for pharyngeal bolus transport can be fully utilized to understand swallowing disorders.
FUTURE PLANS--Analysis of all VFG studies (with various combinations of bolus consistencies, bolus volumes, and head positions) using Snake search algorithm are underway for all controls as well as for persons with various swallowing disorders.
[189] THE EFFECT OF BOLUS VISCOSITY ON THE PHARYNGEAL PHASE OF SWALLOWING: A STUDY USING COMPUTATIONAL FLUID DYNAMICS
Michael W. Chang, MD, PhD; Brigette M. Rosendall, PhD;
Bruce A. Finlayson, PhD
Department of Rehabilitation Medicine, School of
Medicine and Department of Chemical Engineering, College of
Engineering, University of Washington Seattle, WA 98195;
email: mwc@u.washington.edu
Sponsor: The Whitaker Foundation, Rosslyn, VA 22209
PURPOSE--Many factors affect laryngeal penetration during the pharyngeal phase of swallowing. The interplay of these factors cannot be thoroughly investigated using common clinical studies such as videofluorography (VFG). Therefore, there is significant limitation for utilizing VFG to derive guidelines for safe oral feeding. Modification of bolus consistency is a common clinical practice to ensure safe oral feeding, but the limitations of dietary modification and the reasons for its efficacy are not well understood. We propose to study the effect of bolus viscosity on the pharyngeal phase of swallowing using computational fluid dynamics based on Galerkin finite element analysis.
METHODOLOGY--We constructed a two-dimensional planar model using a computational fluid dynamics software, FIDAP. VFG images were obtained by having control subjects swallow 10 cc of barium-mixed boluses with three consistencies: measured viscosities (centi-poise)/densities (g/cc) of 185/2.84, 5,000/2.36, and 45,000/2.75, respectively. Digitized lateral VFG images from these controls were used to trace the pharyngeal wall motion that was implemented as boundary conditions in the simulation. The simulation was divided into two consecutive phases: 1) the filling phase when the bolus first enters into the pharynx, and 2) the moving boundary phase when pharyngeal peristalsis becomes a dominant force for the bolus transport.
PRELIMINARY RESULTS--Our simulations reveal that the bolus front in the low-viscosity fluid moves faster and breaks off more easily from the main bolus than in the mid- and high-viscosity fluids. Therefore, a low-viscosity fluid is more likely to reach the larynx before it can close. Recirculations form during the peristaltic transport of the low-viscosity fluid, but not when mid- and high-viscosity fluids are swallowed. These recirculations could contribute to laryngeal penetration in situations where they produce high velocities in the direction of the larynx. On the other hand, the simulation indicates that the pharyngeal muscles must generate a greater force to propel higher-viscosity boluses, and thus that persons with impairment of the muscles required to propel the bolus would do better with low-viscosity food. Simulations based on VFG data from a person with brain stem stroke and weakened pharyngeal peristalsis validate this hypothesis.
IMPLICATIONS--Persons with dysphagic often have the most trouble swallowing thin liquids, and their diets are commonly restricted to thick liquids, a practice that is supported by the modeling results. Pharyngeal bolus transport becomes 'viscous-dominant' when the Reynolds number (RE), an estimate of fluid inertial versus viscous forces, is less than one. No apparent additional benefit can be gained by further thickening of the bolus beyond this point. For individuals with reduced pharyngeal peristalsis, who often have impaired oral-tonsil control and delayed laryngeal closure, thickening of the diet should be kept to a minimum (i.e., maintaining RE close to one).
[190] POLESTRIDING EXERCISE AND VITAMIN E FOR MANAGEMENT OF CLAUDICATION PAIN
W. Edwin Langbein, PhD; Eileen G. Collins, PhD, RN;
Cynthia Orebaugh, BSN, RN; Fred N. Littooy, MD; Lonnie
Edwards, MD; Domenic Reda, MS
Rehabilitation R&D Center, Nursing, Medical and Surgical
Services, Hines Cooperative Studies Program Coordinating
Center, VA Hines, Hines, IL 60141; enail:
Langbein@research.hines.med.va.gov
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Project #B2095-RA)
PURPOSE--Persons with atherosclerotic peripheral arterial disease (PAD) of the lower limbs are subject to periods of intermittent claudication, caused by the formation of atherosclerotic plaques which narrow or occlude arteries. This condition results in an inadequate blood flow causing ischemic muscle pain. If unchecked, progressive atherosclerotic disease in the leg arteries will result in tissue damage, ulceration, gangrene, and ultimately amputation. The purpose of this project is to determine the efficacy of utilizing Polestriding (PS), a form of walking that uses muscles of the upper and lower body in a continuous movement similar to cross country skiing, with and without vitamin E supplements for increasing exercise tolerance and management (delaying the onset) of intermittent claudication pain in subjects with PAD.
METHODOLOGY--This clinical trial utilizes a prospective, randomized two-by-two factorial design. Subjects are randomized into four groups after baseline testing is completed: PS with vitamin E, PS with placebo; vitamin E only, placebo only. A sample of 84 subjects with a current diagnosis of PAD, a history of intermittent claudication, and an ankle to brachial index (ABI) <0.85 at rest, and/or <0.60 after exercise are being recruited. Intermittent claudication pain must be the primary limiting factor to maximal exercise during the treadmill test.
Initially, all subjects complete a symptom-limited maximal wheelchair exercise test to screen for coronary artery disease, at least two symptom-limited ramp treadmill tests to establish a stable baseline, a constant load treadmill test, a segmental arterial examination, ABIs determined immediately before and after treadmill walking, Borg's ratio scale to determine subjects' perception of effort and severity of exercise induced claudication pain, a quality of life battery, and daily physical activity recall. Subjects are then randomized.
Those randomized into the PS group receive PS instruction and training; sessions include a 3-5 min warm-up, interval training, and cool down. Each subject's training program is individualized according to the results of the baseline exercise tests. Individuals in the vitamin E/Placebo-only groups come to the laboratory weekly for ABI measurements, and physical activity recall. The walking endurance treadmill test, constant load treadmill test, segmental arterial exams, quality of life testing, and physical activity recall interviews are repeated on all subjects at specified intervals.
PROGRESS--Eighteen males (mean age=61±8 non-PS, 66±8 PS) have been randomized thusfar. Subjects are educated (12 yrs school completed) and moderately obese (body mass index =32.8±5.9 non-PS, 28.6±4.9 PS). Prevalent comorbidities and risk factors include arthritis, hypertension, and smoking. Subjects report that they are able to walk one to two blocks before the onset of claudication pain.
At baseline, subjects were able to walk 622±273 s on a specially designed ramp protocol treadmill test. Ankle brachial indices were diminished in both groups before and after exercise (non-PS indices =0.64±0.21 pre-exercise, 0.33±0.23 post-exercise; PS indices =0.67±0=20 pre-exercise, 0.46±0.19 post-exercise).
FUTURE PLANS--Our principles of interventional prevention and vascular rehabilitation may be applied nationally to create VA special clinics dedicated to enhancement of health via the proposed Polestriding exercise program. The reduction in the need for expensive, and labor intensive hospitalizations would also be cost-effective.
[191] COMPARISON OF LOWER-LIMB ARTERY SIZE IN MEN AND WOMEN WITH AND WITHOUT PERIPHERAL VASCULAR DISEASE: A PILOT STUDY
Bok Lee, MD; German Chu-Aquino, MD; Phyllis Berkowitz,
RVT; Lee E. Ostrander, PhD
VA Medical Center, Castle Point, New York 12511
Sponsor: Department of Veterans Affairs, VA
Rehabilitation Research and Development Service, Washington,
DC 20420
(Pilot Project #A2086-PA)
PURPOSE--There is controversy regarding difference in artery size and treatment outcomes of women versus men. The objective of this study is to determine whether there is a difference in lower extremity artery size between men and women; whether lower extremity artery size is related to body surface; and whether lower extremity artery size is predictive of degree of vascular disease and bypass outcome.
METHODOLOGY--Height, weight, and body frame will be noted and intragroup match attempt will be done in order to minimize intragroup variables. Vascular status will first be assessed by segmental Doppler pressure profile and Doppler arterial blood flow waveforms. If noninvasive vascular studies are within normal range, the volunteer will then proceed to the second phase of the study which is having the peripheral artery size measured and blood flow velocity readings using Duplex scan imaging with spectra analysis. The common femoral, superficial femoral, profunda, popliteal, and posterior tibial arteries will be evaluated. When indicated, residual lumen will also be measured (% stenosis). Testing will be performed by a single Registered Vascular Technologist using the same Duplex imager, in order to eliminate technique and/or technical variables. Vessels will be imaged in both transverse and longitude planes. Duplex imaging examinations will allow for remeasurement by an independent observer.
This is a prospective, transverse and comparative study. Twenty volunteer controls (10 male and 10 female) with comparable height and weight will have diameter measurements of the arteries of the lower extremity (common, femoral, superficial femoral, profunda, popliteal, and posterior tibial arteries using Duplex scanning techniques. Correlation will be made with height and weight. Fifty persons (25 male and 25 female) with arterial insufficiency of the lower limbs will have measurements of artery size following the same protocol as the controls. The results be evaluated with t-paired tests and analysis of variance.
PROGRESS--The epidemiological knowledge of the measurement of artery size and its correlation with sex, height, and weight will help identify, in a more systemic and scientific manner, the possible risk factors. It will reveal if there is a significant difference in the size of the arteries of the lower extremity in healthy and diseased women by having an objective comparative with men. Blood flow velocities obtained will delineate normal velocities and velocities in varying degrees of disease.
To date, five females and one male have had screening for group designation in this study. The females qualified as controls (no peripheral vascular disease). Body surface areas were calculated in all volunteers and a match with opposite gender volunteers will be done. The volunteers with peripheral vascular disease had Duplex imaging and artery sizing and this information is being analyzed. The five females are scheduled for imaging shortly.
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Last revised Fri 04/30/1999