The Repetitive Saliva Swallowing Test (RSST) is in widespread clinical use as a highly sensitive, low-risk method of dysphagia screening. However, conducting the RSST is challenging when laryngeal elevation cannot be confirmed due to thick cervical subcutaneous fat or high positioning of the thyroid cartilage. During evocation of the swallowing reflex, movement is observable in both the suprahyoid and infrahyoid muscles. Therefore, in the present study, we investigated whether it was possible to improve the accuracy of RSST by concurrent palpation of the thyroid cartilage and the inferior aspect of the mandible. This hypothesis was verified by videofluorographic (VF) assessment of swallowing in addition to simultaneous measurement of surface electromyography (SEMG) and swallowing sounds. Methods comprised simultaneous measurement of 1) VF, SEMG and palpation of the inferior aspect of the mandible in four healthy adults; and 2) SEMG, palpation of the thyroid cartilage, palpation of the inferior aspect of the mandible and swallowing sounds in 20 healthy adults. When reflex was detected by palpation, a corresponding mark was made by the investigator on the EMG. Muscle activity was calculated using integration after absolute value processing. SEMG was recorded from the suprahyoid and infrahyoid muscles. The following results were obtained. 1) Comparison of the swallowing reflex marks made for swallowing sounds and during palpation revealed that the swallowing reflex detection rate was significantly increased by palpation of the suprahyoid muscles (95%) compared with thyroid cartilage palpation alone (58%). Furthermore, suprahyoid muscle group activation was significantly greater during evocation than during failed attempts. These findings suggest that the accuracy of RSST can be improved by concurrent palpation of the inferior aspect of the mandible in patients in whom confirmation of the swallowing reflex is difficult using thyroid cartilage palpation alone. In addition 2) Up and down movements of the larynx thought to be swallowing hesitation (swallowing reflex failed attempt) were observed on VF in addition to laryngeal elevation and epiglottic inversion (swallowing reflex evocation).
The purpose of this study was to investigate the effects of sensory information in the anticipatory stage of feeding on lip closing pressure during food capturing.
The subjects were 20 healthy young adults (10 males: 23.3±2.2 years of age, 10 females: 23.5±3.2 years of age).
Soft jelly-type food was fed to them in the following four manners: (1) with their eyes closed and being given no information about the food, (2) with their eyes closed and being told what they were about to eat, (3) with their eyes open and being told what they were about to eat, and (4) self feeding with their eyes open and being told what they were about to eat. Each action was performed three times and the food was chosen randomly from eight sorts having different tastes but similar textures.
A strain gauge transducer was embedded in the feeding spoon in advance, and lip closing pressure during food capturing was measured and recorded. Both the average and relative standard deviation of strength, duration, and waveform of the lip closing pressure were analyzed and compared between the four conditions.
The results showed that:
1）The pressure strength showed no significant difference between the four conditions, but the male subjects tended to show a larger pressure in self feeding.
2）The duration of the pressure was significantly longer when subjects had no visual information.
3）The personal relative standard deviation of the pressure strength was large when male subjects had no information or when female subjects fed themselves.
4）The personal relative standard deviation of the pressure duration showed no significant difference between the four conditions.
5）Without visual information, the waveform tended to have two peaks, one of which was smaller and appeared before the main peak.
These experiment results suggested that sensory information affects the lip pressure by altering the duration, stability, and style of the pressure.
Objective: To understand the role of tongue position for pharyngeal swallowing, the effects of altered tongue positions on hyolaryngeal movement and pharyngo-esophageal segment (PES) opening were investigated.
Method: Thirteen normal adults (22–38 years old) participated in the experiment. Each subject swallowed two volumes (3 cc and 10 cc) of thickened liquid with contrast media under four tongue positions (normal, upper, lower, and no-contact). Hyoid bone and laryngeal displacement (vertical and horizontal directions) and the degree and duration of PES opening were measured with fluoroscopic images.
Results: The magnitude of hyoid bone displacement was greater for normal and upper positions (15.1–16.6 mm) than for lower and no-contact positions (11.1–14.9 mm). The magnitude of laryngeal displacement was invariant for tongue positions and volumes (20.1–24.7 mm). There was a moderate positive correlation between the degree of PES opening and the horizontal displacement of hyoid bone.
Conclusion: Upper tongue positions facilitate hyoid bone movement and PES opening.
[Purpose] The present study evaluated expiratory muscle strength training (EMST) as a method of strengthening the suprahyoid muscles in 15 healthy volunteers (10 males and 5 females; mean age, 29.3 years).
[Methods] We measured the electromyographic activity of the suprahyoid muscles during EMST, the Mendelsohn maneuver and an isometric head lifting exercise. The EMST load pressure was set at 25% and 75% of maximum expiratory mouth pressure (PEmax) and the participants forcibly exhaled at maximal inspiratory level. We compared the root mean square (RMS) and mean power frequency (MPF) using continuous wavelet frequency analysis for 1 second at high amplitude during training at each level.
[Results] Suprahyoid muscle activity (% RMS) peaked (208.5±106.0%) during EMST at 75% PEmax and significantly differed from that at 25% PEmax (155.4±74.3%), during the Mendelsohn maneuver (88.8± 57.4%) and during isometric head lifting (100%; normalization). In addition, continuous wavelet frequency analysis showed that a high-power component was sustained in the high frequency zone area during EMST. The MPF value was the highest (127.8±20.7 Hz) during EMST at 75% PEmax, which significantly differed from that at 25% PEmax (107.6±20.1 Hz) and isometric head lifting (100.4±19.3 Hz).
[Conclusions] The increased activity of motor unit recruitment and of type II fibers in the suprahyoid muscles indicate that EMST is an effective method of strengthening these muscles.
[Purpose] We evaluated the risk factors for aspiration pneumonia in patients with severe motor and intellectual disabilities (SMID).
[Subjects and Methods] We performed a videofluoroscopic swallow study (VFSS) and tartaric acid reflex cough test (RCT) in 32 SMID patients with clinically apparent aspiration and studied the risk factors for aspiration pneumonia.
Based on clinical symptoms, the subjects were divided into the following two groups: the “permission group” and the “non-permission group.” The permission group included patients who experienced choking and wheezing and produced sputum during meals but had no history of fever. The non-permission group included patients who exhibited aspiration symptoms during meals and ＞3 episodes of fever in half a year. The two groups were compared for individual factors of VFSS and tartaric acid RCT.
[Results] In the VFSS, 20 (62.5%) of the 32 patients showed aspiration, all of which were silent. These 20 patients were categorized into the permission group (n＝10) and non-permission group (n＝10). No significant difference was observed in the factors determined by the VFSS. On the other hand, in the comparison of tartaric acid RCT, 100% in the permission group showed a reaction, whereas 50% in the non-permission group showed no reaction. A significant difference was found between the two groups (p＜0.01).
[Conclusion] These results suggest that the tartaric acid RCT is effective for detecting the risk of aspiration pneumonia in SMID patients.
[Purpose] It is known that the anticipatory stage including recognizing and understanding food plays an important role in the feeding process. The aim of this study was to clarify the effects of cognition in the anticipatory stage of feeding, therefore, the relationship between sensory input such as visual and verbal information and the food-capturing motion was investigated.
[Methods] The subjects were 20 healthy young adults (10 males and 10 females). The feeding tasks observed were the following: (1) with their eyes closed and being given no information about the food, (2) with their eyes closed and being told what they were about to eat, (3) with their eyes open and being told what they were about to eat, and (4) self-feeding with their eyes open and being told what they were about to eat.
In this research, time of mouth-opening, position of spoon, maximum mouth-opening and length of spoon were measured on a personal computer three-dimensionally.
[Results] Firstly, the measurement of lip motion indicated that the subjects whose eyes had been kept closed with no auditory information, under condition 1, began to open their mouths 0.3 seconds after the spoon reached their lower lips on average. Meanwhile, the participants under conditions 2 and 3 began to open their mouths earlier than the other conditions. The average time of mouth-opening was the shortest in subjects under condition 4.
Secondly, the measured position of the spoon tended to be farther in condition 4 than the other conditions. In contrast, there was no significant difference between the results of the items under conditions 1 and 2.
Thirdly, though maximum mouth-opening showed little differences among the four conditions, the result of condition 4 tended to be greater than that of conditions 1 and 2.
Finally, the mean length of spoon was greater for the subjects under conditions 1 and 2, whereas the personal coefficient of variance was dramatically greater under conditions 3 and 4.
[Conclusion] This study suggests that a limitation on sensory information can affect prefeeding motions, and hence auditory information may alleviate the influence by offsetting the loss of visual information.
[Purpose] The purpose of this study was to develop an oral health behavior assessment scale based on a PRECEDE-PROCEED model for older adults in a community with the goal of developing an oral care program that the older adults can personally control.
[Methods] This study was approved by the ethics committee of our university. An oral health behavior assessment scale (OHBAS) was developed based on the results obtained by a focus group interview of older adults using a PRECEDE-PROCEED model containing 41 items. A questionnaire survey about the OHBAS was conducted among 1,883 older adults and their family living together.
[Results] 1. Eight-hundred and three responses to the OHBAS were analyzed. The subjects had an average age of 75.7 years, 42.0% of whom were men and 47.4% of whom had 20 or more teeth.
2. Twenty-five items were selected for the OHBAS from the results of frequency distribution, mean and factor analysis.
3. Six factors were obtained by exploratory factor analysis, i.e., “quality of life,” “oral health,” “oral health behavior,” “predisposing factors,” “reinforcing factors,”and“enabling factors,”similar to the structure of the PRECEDE model, which consists of 7 factors. Construct validity was analyzed by covariance structure analysis. As goodness of fit between the constructs is the basis of the PRECEDE model, the goodness of fit index showed 0.866, and adjusted goodness of fit index showed 0.837. Hence, construct validity has a tolerance level.
4. Reliability was analyzed by internal consistency. Cronbach's a was 0.773 for overall scores.
[Conclusion] These results suggest that the developed OHBAS has a tolerance level for validity and reliability by statistical analysis.
We researched the cost to prepare a modified diet for dysphagic persons. The subjects were councilors of the Japanese Society of Dysphagia Rehabilitation who considered providing the modified diet for dysphagic persons.
The average number of jelly-type food items that a hospital needs to provide for the modified diet of dysphagic persons is 13 and 16, with regard to staple food and accompanying dish respectively. The average time taken by hospital staff to make the jelly-type food for dysphagic persons was 48 and 63 minutes for staple food and accompanying dish respectively.
The average number of puree-type food items that need to be provided by a hospital for the modified diet of dysphagic persons is 22 and 24, for staple food and accompanying dish respectively. The average time taken by hospital staff to make the puree-type food for dysphagic persons was 65 and 95 minutes for staple food and accompanying dish respectively.
From these results, we calculated the staff cost based on registered dieticians who had 5 years of experience in national hospitals. The average cost of a meal with jelly-type food was 109 and 114 yen for staple food and accompanying dish respectively. The average cost of a meal with puree-type food was 77 and 100 yen for staple food and accompanying dish respectively. The average cost of a meal that consisted of easily masticated food was 77 and 100 yen with regard to staple food and accompanying dish respectively.
We estimated that the number of patients who eat this modified diet in general hospitals and care hospitals is 420 thousand.
[Purpose] There is a high frequency of swallowing difficulty complaints among patients with Sjögren's syndrome which impairs their quality of life. This study aimed to evaluate the efficacy of pilocarpine hydrochloride for the symptom by analyzing the change of saliva flow rate, subjective evaluation of dry mouth and videofluorography findings.
[Methods] Three female patients (aged 67, 45 and 35 years) diagnosed as primary Sjögren's syndrome were enrolled in this study. Cases A and B took 15 mg pilocarpine daily and case C took 5 mg. Before and after pilocarpine treatment, the stimulated saliva flow values during chewing of gum, the subjective evaluation of dry mouth on a 100-mm visual analog scale (VAS) and the oropharyngeal transit time obtained from videofluoroscopic images using 1.5 g of barium cookie as a test food were examined.
[Results] After one month of treatment, the saliva flow value of case A increased by 0.7 ml/10 min, that of case B decreased by 0.5 ml/10 min and that of case C increased by 18.0 ml/10 min. The subjective evaluation of dry mouth on VAS of case A was improved from 91 mm to 26 mm, case B from 52 mm to 0 mm and case C from 79 mm to 18 mm. Case A could not swallow the 1.5 g cookie before the treatment, but could swallow it in 56 seconds after the treatment. The oropharyngeal transit time of case B shortened from 46 seconds to 38 seconds and that of case C from 23 seconds to 13 seconds.
[Conclusion] After the pilocarpine treatment, the subjective evaluation of dry mouth and the oropharyngeal transit time of these three cases were improved, while the stimulated saliva flow values during chewing of gum changed variously. It is suggested that the mouth was moistened by an increased unstimulated saliva flow and a food bolus was formed smoothly.