Effects of Bolus Volume on Pharyngeal Contact Pressure During Normal Swallowing

This cross-sectional study investigated the effect of bolus volume on contact pressure within the pharynx and upper esophageal sphincter (UES). Three solid-state manometric pressure sensors were placed transnasally into the pharynx and the proximal esophagus of 40 participants (gender equally represented and between the ages of 20 and 45 years). Participants completed five repetitions each of three swallowing conditions: 5-, 10-, and 20-ml water bolus swallows. Repeated-measures ANOVA revealed no significant differences in the amplitude of pharyngeal contact pressure between the three swallowing conditions (sensor 1: p = 0.627, sensor 2: p = 0.764). Similarly, for durational measures nonsignificant main effects were found at both sensor 1 (p = 0.436) and sensor 2 (p = 0.350). Significant differences were found in UES pressure between the three conditions of bolus swallows (p = 0.000), with negative pressure in the UES inversely proportionate to bolus volume. However, durational measures of UES relaxation pressure were not significantly different between all conditions (p = 0.473). This study demonstrates no significant pressure differences of amplitude and duration between swallowing conditions in the pharynx. At the level of the UES, smaller boluses generated greater negative pressure.     

Oropharyngeal swallowing in normal adults of different ages.

In an effort to evaluate the effect of normal aging on oropharyngeal events of swallowing, 80 normal volunteers, stratified by gender into four age groups, were studied. Liquid and semisolid swallows were performed and recorded simultaneously using videofluoroscopy and manometry. Several parameters, including total duration of oropharyngeal swallowing, were significantly longer in the oldest age group than in any other age group. A delay in initiation of maximal hyolaryngeal excursion primarily accounted for the longer durations with increased age. Significant durational changes also were found as a function of bolus consistency and presence or absence of the manometry tube. Females had a longer duration of upper esophageal sphincter (UES) opening. The amplitude of pharyngeal pressures, duration of peak pharyngeal pressures, and rate of propagation of the contractions were not significantly different for age, gender, or consistency of bolus. No significant differences were found between age groups or between genders in UES pressure. Normal aging affects some parameters of swallowing, while others are preserved.     

Cricopharyngeal myotomy may be effective treatment for selected patients with neurogenic oropharyngeal dysphagia

The role of cricopharyngeal (CP) myotomy in the management of neurogenic oropharyngeal dysphagia remains controversial. A review of the literature regarding outcomes of CP myotomy for dysphagia in the setting of a variety of neurological disorders indicates a preponderance of favorable results. There are several potential explanations for reported improvement after CP myotomy for neurogenic dysphagia, including the possibility that it is an effective treatment, at least for selected patients. If this is true, appropriate selection criteria for this treatment of neurogenic dysphagia may include (1) intact voluntary initiation of swallowing, (2) adequate propulsive force generated by the tongue and pharyngeal constrictors, (3) videofluorographic demonstration of obstruction to bolus flow at the CP segment (rather than merely retention in the pharyngeal recesses), (4) manometric evidence of relatively elevated CP pressure in relation to the pharynx, and (5) relatively favorable neurological prognosis. The effectiveness and safety of CP myotomy for patients with neurogenic dysphagia are unlikely to be resolved without a prospective, controlled multicenter study enrolling patients who meet such criteria.     

Effects of body position and bolus consistency on the manometric parameters and coordination of the upper esophageal sphincter and pharynx

The development of a solid-state intraluminal sphincter transducer has alleviated many of the problems associated with manometric studies of the upper esophageal sphincter (UES) and pharynx (P). We used this technology to study the effect of position (upright vs. supine) on resting UES pressures and the pressure dynamics of the UES/P complex during both wet and dry swallows in 11 normal volunteers and the effects of foods of different consistencies on the UES/P swallow dynamics in 10 normal volunteers. The UES/P coordination parameters were defined as the 15 time intervals that can be measured between any 2 of 6 pertinent points: the beginning, peak, and end of the pharyngeal contraction and the beginning, nadir, and end of the UES relaxation. Data from both the circumferential transducer used to measure sphincter pressures and a standard microtransducer used to measure pharyngeal pressures were collected on-line by an Apple IIe microcomputer and analyzed by programs written in our laboratory. Significant changes in swallow coordination were measured between upright and supine swallows of the same bolus size, between wet and dry swallows in the same position, and among foods of varying consistencies. Resting UES pressure was unchanged by position and pharyngeal contraction pressure was unchanged by bolus size or consistency.     

Videofluorographic Study of Swallowing in Parkinson's Disease

We studied 16 patients with Parkinson's disease (PD) with dysphagia and 8 young and 7 elderly normal controls videofluorographically to evaluate the nature of swallowing disorders in PD patients. In 13 patients, abnormal findings in the oral phase were residue on the tongue or residue in the anterior and lateral sulci, repeated pumping tongue motion, uncontrolled bolus or premature loss of liquid, and piecemeal deglutition. Thirteen patients showed abnormal findings in the pharyngeal phase, including vallecular residue after swallow, residue in pyriform sinuses, and delayed onset of laryngeal elevation. Ten of these patients also showed abnormal findings in both the oral and pharyngeal phases. Aspiration was seen in 9 patients. The oral transit duration was significantly longer in the patients with and without aspiration than in the control subjects. The stage transition duration, pharyngeal transit duration, duration of the upper esophageal sphincter (UES) opening, and total swallow duration were significantly longer in the patients with and without aspiration than in the young controls, but were not longer than in the elderly controls. These durational changes in the pharyngeal phase of swallowing were similar to those in the elderly controls. The findings suggest that the disturbed motility in the oral phase of swallowing may be due to bradykinesia. Although PD patients with dysphagia evince a variety of swallowing abnormalities, the duration of pharyngeal swallowing may remain within the age-related range until the symptoms worsen.     

Morphologic Parameters of Normal Swallowing Events Using Single-Shot Fast Spin Echo Dynamic MRI

This study was designed to determine visible and measurable morphological parameters in normal swallowing using dynamic MRI with single-shot fast spin echo (SSFSE), as a preliminary study in view of noninvasive MRI swallowing evaluation in patients with dysphagia. Seven healthy volunteers aged 24–40 underwent dynamic MRI with SSFSE, with a 1.5-T unit, using a head and neck antenna. Patients repeated dry swallow, water swallow, marshmallow swallow, cake swallow, and cookie chewing for a total of five series, with 15 acquisitions per series at a rate of 700 ms per acquisition. A checklist of swallowing events and anatomic landmarks was used to determine which anatomic landmarks are always visible, which phases or swallowing movements are always visible, and which landmarks can be used to measure oral and pharyngeal motion in swallowing. The oral preparatory, oral, and oropharyngeal phases of deglutition were visible in all cases. No aspiration, reflux, or abnormal residue was observed. Spatial resolution allowed for anatomical measurements of laryngeal elevation, oropharyngeal diameter, and tongue base and velum displacement in all cases. SSFSE dynamic MRI is pertinent for evaluation of the anatomical and physiological characteristics of swallow. The temporal parameters, however, cannot be studied using this technique. Motion artifacts preclude its use in the study of mastication. It remains complementary to videofluoroscopy and other techniques in swallow evaluation.     

High‐resolution impedance manometry facilitates assessment of pharyngeal residue and oropharyngeal dysphagic mechanisms

The utility of high‐resolution impedance manometry (HRIM) for evaluating oropharyngeal dysphagia (OPD) has been investigated. These approaches are limited because of the sophisticated methodology. A method of transforming HRIM into a simple and useful diagnostic tool for evaluating OPD is needed. A videofluoroscopic swallowing study (VFSS) and HRIM were performed by independent blinded examiners in 26 consecutive healthy volunteers (12 men; median age, 56.5 years) and 10 OPD patients (five men; median age, 59.5 years). Upper esophageal sphincter (UES) relaxation parameters were measured using a standard HRIM protocol. Peristalsis and bolus transit of the pharyngoesophageal (PE) segment were assessed using an HRIM‐modified protocol in which the catheter was pulled back 10 cm. PE bolus transits were evaluated with an impedance contour pattern (linear vs. stasis) method. A significant difference was observed between the manometric measures of healthy volunteers and OPD patients for only the duration of pharyngeal contraction (0.49 ± 0.19 vs. 0.76 ± 0.33 s, P = 0.04). The percentage agreement and kappa value for detecting pharyngeal residue between the VFSS and the impedance analysis were 100% and 1.00, respectively. HRIM allowed for comprehensive assessment of abnormal pharyngeal components that caused pharyngeal residue on VFSS in two patients; reduced base of the tongue versus weak pharyngeal contraction in one, and reduced relaxation of the UES versus reduced laryngeal elevation in the remaining patient. Our findings demonstrated that HRIM using a simple methodology (i.e., pull‐back of the catheter) detected pharyngeal residue through a simple analysis of the impedance contour pattern (linear vs. stasis). Furthermore, HRIM facilitated a comprehensive assessment of OPD mechanisms and recognition of subtle abnormalities not yet visible to the naked eye on VFSS.     

High-Resolution Manometry of Pharyngeal Swallow Pressure Events Associated with Effortful Swallow and the Mendelsohn Maneuver

Effortful swallow and the Mendelsohn maneuver are two common strategies to improve disordered swallowing. We used high-resolution manometry (HRM) to quantify the effects of these maneuvers on pressure and timing characteristics. Fourteen normal subjects swallowed multiple, 5-ml water boluses using three techniques: normal swallow, effortful swallow, and the Mendelsohn maneuver. Maximum pressure, rate, duration, area integral, and line integral were determined for the velopharynx and tongue base. Minimum pressure, duration of pressure-related change, duration of nadir pressure, maximum preopening and postclosure pressure, area integral, and line integral were recorded for the upper esophageal sphincter (UES). Area and line integrals of the velopharyngeal pressure curve significantly increased with the Mendelsohn maneuver; the line integral increased with the effortful swallow. Preopening UES pressure decreased significantly for the Mendelsohn, while postclosure pressure tended to increase insignificantly for both maneuvers. UES area and line integrals as well as nadir UES pressure duration increased with both maneuvers. Maneuver-dependent changes were observed primarily at the velopharynx and UES. These regions are critical to safe swallowing, as the velopharynx provides positive pressure at the bolus tail while the UES allows a bolus to enter the esophagus without risk of regurgitation. Integrals were more responsive than maximum pressure or duration and should be investigated further.     

Dynamic aspects of lingual propulsive activity in swallowing

This investigation concerned the effect of different bolus volumes on the characteristics of lingual propulsive activity in swallowing. Young normal subjects were asked to perform dry swallows and swallows of 5, 10, and 15 ml of water. Tongue activity was recorded by tracking multiple gold pellets affixed to the tongue, utilizing the specialized research capabilities of the X-ray Microbeam facility at the University of Wisconsin. The major differences were between dry and liquid swallows, with dry swallows showing smaller range of movement, higher tongue position at the initiation of lingual propulsive activity, a slightly different direction of motion, a humped or flat rather than grooved cross-sectional contour of the tongue, lower peak velocity of motion, and slower progression of activity from tongue blade to dorsum. Within the 5–15 ml range of liquid bolus volumes, fewer consistent differences were found as a function of bolus size, and some marked individual differences in swallowing patterns were seen. Data are presented on normal within-subject variability in swallowing, with discussion of the possible contribution of sensory assessment of bolus size to the modification of oral and pharyngeal characteristics of swallowing.     

Oropharyngeal dysphagia due to iatrogenic neurological dysfunction

Oropharyngeal dysphagia due to iatrogenic neurological dysfunction may relate to either medication side effects or surgical complications. There are several general mechanisms by which neurological side effects of medications can cause or aggravate oropharyngeal dysphagia. These include decreased level of arousal, direct suppression of brainstem swallowing regulation, movement disorders (dyskinesias, dystonias, and parkinsonism), neuromuscular junction blockade, myopathy, oropharyngeal sensory impairment, and disturbance of salivation. Postsurgical oropharyngeal dysphagia due to neurological dysfunction has been described in association with carotid endarterectomy, esophageal cancer surgery, anterior cervical fusion, and ventral rhizotomy for spasmodic torticollis. A potential explanation for oropharyngeal dysphagia following these surgical procedures is intraoperative mechanical disruption of the innervation of the pharyngeal constrictor muscles by the pharyngeal plexus. Posterior fossa and skull base surgery can lead to dysphagia as a result of intraoperative damage to brainstem centers and/or cranial nerves involved in swallowing. Perioperative stroke is the most likely explanation for oropharyngeal dysphagia appearing acutely following surgery, especially if the type of surgery predisposes to embolism or hypoperfusion.     

The Effects of Cervical Bracing Upon Swallowing in Young,Normal, Healthy Volunteers

Abstract The purpose of this study was to evaluate radiographically the effects of cervical bracing upon swallowing thin liquids and solid food in normal adults under three cervical bracing conditions. This was a prospective, repeated measures design study. Seventeen healthy adult volunteers between the ages of 30 and 50 were recruited from hospital staff. All subjects reported no previous history of swallowing difficulty or diseases that might affect swallowing. Subjects were radiographically observed swallowing thin liquids and solid food without cervical bracing and with three common cervical orthoses (Philadelphia collar, SOMI, and halo-vest brace). Order of bracing and type of bolus were randomized. Changes in swallowing function (point of initiation of swallow response, presence of pharyngeal residue, airway penetration, hyoid bone movement, diameter of oropharyngeal airway, and durational measurements) were analyzed by two independent raters. Eighty-two percent (14/17) of the subjects demonstrated radiographic changes under one or more of the bracing conditions. Forty-seven percent (8/17) of subjects demonstrated changes with point of initiation of the swallow response, 59% (10/17) demonstrated increased pharyngeal residue, and 23.5% (4/17) demonstrated changes with bolus flow with laryngeal penetration present. Aspiration did not occur under any of the bracing conditions. Changes noted in durational measurements for oral containment and total pharyngeal transit under the bracing conditions were not considered statistically significant. This study shows that cervical bracing does change swallowing physiology in normal healthy adults.     

Bolus Location at the Initiation of the Pharyngeal Stage of Swallowing in Healthy Older Adults

This study characterized the vertical position of the bolus head at the onset of the pharyngeal swallow in healthy older adults. Lateral-view videofluoroscopic (VF) images were obtained from ten healthy volunteers (age-71.6 ± 7.5 years, mean± SD) as they swallowed 5-cc thin liquid barium aliquots. For each swallow, the bolus head and several anatomic landmarks were digitally recorded from the image in which pharyngeal swallow-related hyoid bone elevation began. Vertical distance between the bolus head and the intersection of the tongue base and mandibular ramus (TMI) was computed. Bolus head position at swallow onset ranged from 47.4-mm above to 34.9-mm below the TMI (2.2 ± 14.4-mm, mean ± SD). Although the bolus head was below the level of the TMI for the majority of swallows, neither penetration nor aspiration occurred. For individual subjects, mean bolus head position ranged from 25.8 ± 5.0-mm above to 15.5 ± 6.5-mm below the TMI. Whereas five of ten subjects initiated the pharyngeal swallow with the bolus head consistently above or consistently below the TMI, five subjects initiated swallowing with the bolus head either above or below the TMI across trials. Older adults commonly initiate thin-liquid swallows with the bolus head well below the TMI without associated penetration or aspiration. Thus, bolus position alone does not differentiate between normal and pathologic swallowing within the healthy elderly. Bolus position at pharyngeal swallow onset can vary substantially from trial to trial within an individual, suggesting that the triggering of swallowing depends on multiple influences. This research was supported by NSERC grant No. 0GPO171208 and an Ontario Ministry of Health Career Scientist Award to REM.     

Monitoring of Pharyngeal and Upper Esophageal Sphincter Activity with an Arterial Dilation Balloon Catheter

In patients with dysphagia and radiologic signs of dysfunction of the upper esophageal sphincter (UES), manometry is helpful in giving a better understanding of muscular activity during swallowing. Traditional manometric methods include use of perfusion catheters or solid-state intraluminal strain gauges. The rapid and asymmetric pressure variations in the UES and difficulties compensating for the pharyngolaryngeal elevation during swallowing limit the value of these methods. We used an arterial balloon dilation catheter as a probe in manometric recording of the UES in 28 healthy volunteers. Simultaneous perfusion manometry of the pharynx with the same catheter was performed to assess the coordination of the muscular activity in the esophageal entrance during swallowing. The catheter was well tolerated by all subjects. We found an average resting pressure in the UES of 31.0 mmHg, and the average maximum pressure during contraction was 89.0 mmHg. The average duration of the swallowing act was 3.9 s. All subjects displayed a complete UES relaxation and a normal coordination of propagated pressure in the hypopharynx and UES. The results were highly reproducible and the interindividual range was low. Arterial dilation catheters are safe and have suitable physical properties for pressure monitoring in the UES.     

The Effects of Intraoral Pressure Sensors on Normal Young and Old Swallowing Patterns

Lingual pressure generation plays a crucial role in oropharyngeal swallowing. To more discretely study the dynamic oropharyngeal system, a 3-bulb array of pressure sensors was designed with the Kay Elemetrics Corporation (Lincoln Park, NJ). The influence of the device upon normal swallowing mechanics and boluses representative of flow relative to age and bolus condition was the focus of this study. Twelve healthy adults in two age groups (31 ± 5 years, 2 males and 4 females, and 78 ± 7 years, 2 males and 4 females) participated. Each subject was instructed to swallow four boluses representative of conditions with and without three pressure sensors affixed to the hard palate. Postswallow residue at four locations, Penetration/Aspiration Scale scores, and three bolus flow timing measures were assessed videofluoroscopically with respect to age and bolus condition. The only statistically significant influences attributable to the presence of the pressure sensors were slight increases in residue in the oral cavity and upper esophageal sphincter with some bolus consistencies, 8% more frequent trace penetration of the laryngeal vestibule predominantly with effortful swallowing, and variances in oral clearance duration. We conclude that the presence of the pressure sensors does not significantly alter normal swallowing patterns of healthy individuals. This article is GRECC No. 03-01. This work was supported by NIH Grant NS24427 and VA Grant E727-2RA.     

Pharyngoesophageal Manometry with an Original Balloon Sensor Probe for the Study of Oropharyngeal Dysphagia

The goal of our study was to verify the clinical applicability of an original balloon sensor probe for the manofluorographic study of oropharyngeal dysphagia. A prototype apparatus for manofluorography was developed and a standard perfused probe for esophageal manometry was modified by applying fluid-filled floppy balloons 0.5-, 1-, and 2.5-cm long. A group of healthy volunteers and a group of patients affected by oropharyngeal dysphagia underwent manofluorography. Statistically significant differences were calculated between the groups with regard to the upper esophageal sphincter (UES) basal and postrelaxation contraction pressures (p < 0.05, Students t test, 2.5- vs. 1-cm-long balloon sensors). In the group of patients versus the group of healthy volunteers, statistically significant differences were calculated with regard to pharyngeal intrabolus pressure, UES residual and UES postrelaxation contraction pressures, and mean diameter of the UES during maximal opening (p < 0.05, Students t test). A strong negative correlation (r = –0.92, p = 0.001; r = –0.93, p = 0.006 linear regression analysis) was observed between intrabolus pressure and UES diameter during maximum opening in the group of patients. The balloon probe demonstrated its reliability and clinical adequacy for the study of swallowing disorders.     

Decreased Tongue Pressure Reflects Symptom of Dysphagia

The tongue plays a key role in oropharyngeal swallowing. It has been reported that maximum isometric tongue pressure decreases with age. The risk for dysphagia resulting from low tongue strength remains unclear. This study was designed to reveal the relationship between tongue pressure and clinical signs of dysphagic tongue movement and cough and to demonstrate the clinical value of tongue pressure measurement in the evaluation of swallowing function. One hundred forty-five institutionalized elderly in five nursing homes participated. Evaluation of physical activity with self-standing up capability and mental condition with Mini Mental Status Examination (MMSE) were recorded. Maximum tongue pressure was determined using a newly developed tongue pressure measurement device. Voluntary tongue movement and signs of dysphagic cough at mealtime were inspected and evaluated by one clinically experienced dentist and speech therapist. The relationship between level of tongue pressure and incidence of cough was evaluated using logistic regression analysis with physical and mental conditions as covariates. Tongue pressure as measured by the newly developed device was significantly related to the voluntary tongue movement and incidence of cough (p < 0.05). The results of this study suggest that tongue pressure measurement reflects clinical signs of dysphagic tongue movement and cough and that measurement of tongue pressure is useful for the bedside evaluation of swallowing.This study was supported by a grant-in-aid from the Ministry of Health, Labour and Welfare (tyoujyu-14-020).     

Swallowing Physiology of Toddlers with Long-Term Tracheostomies: A Preliminary Study

This study investigated the swallowing physiology of toddler-aged patients with long-term tracheostomies. Structural movements and motility of the pharyngeal stage of swallowing were studied in four toddlers ranging in age from 1:2 (years:months) to 2:9 with long-term tracheostomies. A patient aged 1:2 years with no tracheostomy served as a toddler model for comparison. Videofluoroscopic recordings of the patients' liquid and puree bolus swallows were analyzed for a) onset times for pharyngeal stage events, laryngeal vestibule closure, and tracheostomy tube movement; b) timeliness of swallow response initiation; and c) pharyngeal transport function. Results found differences in timing of pharyngeal stage movements between the tracheostomized patients and the patient with no tracheostomy. Laryngeal vestibule closure occurred before or within the same 0.033-s video frame as onset of upper esophageal sphincter (UES) opening in the patient with no tracheostomy, but occurred 0.033–.099 s after onset of UES opening in the tracheostomized patients. The time line required to close the laryngeal vestibule once the arytenoids began their anterior movement was longer in the tracheostomized patients than in the patient with no tracheostomy and was associated with laryngeal penetration. The patient with no tracheostomy displayed superior excursion of the arytenoid and epiglottis during the swallowing; the tracheostomized patients did not. No association was found between onset of tracheostomy tube movement and laryngeal vestibule closure. Delayed swallow response initiation was observed across tracheostomized patients at a mean frequency of 45% with associated penetration. Pharyngeal dysmotility was not observed. Findings supported the concept that long-term tracheostomy in toddler-aged patients affects swallowing physiology.     

Event Sequence Variability in Healthy Swallowing: Building on Previous Findings

This study builds on previous work by Kendall, Leonard, and McKenzie, which investigated event sequence variability for 12 paired events during swallowing by healthy volunteers. They identified four event pairs that always occurred in a stereotyped order and a most common occurring overall order of events during swallowing. In the current study, we investigated overall event sequencing and the same four paired events in a sample of swallows by healthy young (under 45 years old) volunteers. Data were collected during a 16-swallow lateral videofluoroscopy protocol, which included manipulations of bolus volume, barium density, bolus viscosity, and swallow cueing. Our results agreed with previous findings that variable event sequencing is found in healthy swallowing, and, in regard to obligatory sequencing of two paired events, movement of the arytenoids toward the base of the epiglottis begins prior to upper esophageal sphincter (UES) opening and maximum hyolaryngeal approximation occurs after UES opening. However, our data failed to replicate the previous findings that there is obligatory sequencing of maximum pharyngeal constriction after maximal UES distension and the UES opens before bolus arrival at the UES. The most common observed overall event sequence reported by Kendall et al. was observed in only 4/293 swallows in our dataset. Manipulations of bolus volume, bolus viscosity, barium concentration, swallow cueing, and swallow repetitions could not completely account for the differences observed between the two studies.     

健康老年妇女吞咽功能的研究

目的　通过电视X线透视吞咽功能的研究 ,评价健康老年妇女液体吞咽运动 ,并对液体吞咽运动的影响因素进行分析。　方法　 4 0例健康老年妇女 ,老年前期组 (5 0～ 5 9岁 ) 2 0例 ;老年组 2 0例 ,年龄 6 0～ 79岁。进行电视X线透视液体吞咽功能检查 ,分别对口咽部相关结构进行运动学分析 ,比较不同液体食团体及年龄对健康老年妇女吞咽的影响。　结果　 (1 )老年组较老年前期组渗透、口咽部滞留发生率增高 ,两组渗透发生率分别为 :7 5 %、3 8% ;口腔滞留发生率分别为 :1 2 5 %、6 3% ;咽腔滞留发生率分别为 :2 6 5 %、1 7 5 % ;口咽传递时间、腭咽部关闭时间及环咽部开放时间延长 (均为P <0 0 5 ) ;喉、舌骨向上运动距离增大 (P <0 0 5 )。 (2 ) 1 0ml食团较 1ml渗透、口咽部滞留发生率增高 ,两组渗透发生率分别为 :8 8%、2 5 % ;口腔滞留发生率分别为 :1 3 8%、5 0 % ;咽腔滞留发生率分别为 :31 3%、1 3 8% ;口传递时间缩短而环咽部开放时间延长 (均为P <0 0 5 ) ;喉向上、前运动 ,舌骨向前、向上运动的距离增大 (P <0 0 5 )。　结论　临床应用电视X线透视吞咽功能检查并对口咽期吞咽功能进行运动学分析是可行的 ;年龄及食团体积均影响健康老年妇女的液体吞咽功能