In this study, we measured dynamic viscoelastic properties of soft tea jelly made with mixed-type carrageenan, gelatin, and agar. The hardness of each jelly was adjusted to 1 x 10³ N/m².

We examined the correlation of dynamic viscoelastic properties and swallowing properties in tests which were carried out among elderly panelists.

The following results were obtained.

1. The width of the linear region of the agar jelly was the shortest at both temperatures of 10℃ and 20℃. This means that the agar jelly was the most easily deformable jelly.

2. G' of each jelly appeared to decrease a little with decrease of frequency. This suggests that each jelly was a ‘weak gel’ that appeared to have sol-like properties. Therefore, whenever the hardness of the jelly was adjusted to a suitable and equal level, the jelly might have been a ‘weak gel’ which was soft and swallowed easily, no matter what gelling agent was used.

3. Though there was no significant difference among the ease of swallowing of each jelly, there were significant differences among the physical properties, except the hardness. This means that the kind of gelling agent may have had little influence on ease of swallowing when the hardness of the jelly was adjusted to a suitable and equal level.

【Purpose】The purpose of this study was to measure the short-term and long-term effects of external ice massage on salivary secretion in healthy adults.

【Subjects】All subjects were healthy volunteer adults with no history of dysphagia and were not taking medications known to affect salivary flow. Short-term study：36 healthy adults (14 males, 22 females, average age：mean±SD＝29.2 ± 6.5 years). Long-term study：Ice massage group：22 healthy adults (11 males, 11 females, average age：30.4 ± 5.8 years). Control group：15 healthy adults (2 males, 13 females, average age：26.9 ± 5.0 years).

【Methods】Unstimulated whole saliva (UWS) was collected by spitting. Saliva collections were made at almost the same time in the late afternoon to reduce the influence of circadian rhythm on salivary flow rate. UWS samples were weighed every five minutes for 30 minutes and the salivary fiow rate (SFR ml/min) was calculated.

Short-term study：Each subject performed two different saliva collections on two separate days. With ice massage：After 30 minutes of saliva collection, each subject ice-massaged the skin overlying the salivary glands with an ice-filled container for 10 minutes followed by 30 minutes of saliva collection. No ice massage：After 30 minutes of saliva collection, the subject rested for 10-minutes followed by 30 minutes of saliva collection. Long-term study：Ice massage group：Saliva was collected for 30 minutes at least one day before the first ice massage session. Each subject performed three separate 10-minute sessions of ice massage daily for seven days. On the seventh and final day, saliva was collected for 30 minutes without the last session of ice massage. Control group：Saliva was collected for 30 minutes. After seven or eight days, saliva was collected for 30 minutes.

【Results】Short-term study：The paired t-test showed a significant reduction in salivary flow immediately after ice massage (p ＝ 0.002). Long-term study：The paired t-test showed a significant reduction in salivary flow after seven days of ice massage three times a day (p ＝ 0.033).

【Conclusion】 We performed two studies to measure the short-term and long-term effects of ice massage applied to the skin overlying the salivary glands on salivary flow rate. The results suggest that the ice massage reduces salivary flow after a single session of application, and after multiple applications over several sessions. A more thorough study with appropriate controls and a study on patients with sialorrhea should be conducted.

【Purpose】Yogurt (“YG”) is a food which is frequently ingested by children with dysphagia. A number of YGs are now commercially available and the physical properties vary among different products. This study therefore examined the required conditions of YG for oral function in handicapped children.

【Subjects and methods】Among the guardians of 50 handicapped children who have continuously visited an outpatient clinic for treatment of dysphagia in regional medical institutes and care educational centers, a questionnaire survey was performed concerning the ingestion state of YG. Furthermore, the background disease as well as the eating/swallowing function was investigated by referring to individual medial charts in the outpatients' clinic involved. Finally, 12 kinds of commercially available YG and some baby foods which are frequently ingested by the subjects were tested for mechanical and physical properties.

【Results】YG was ingested twice a day in 42％ of them. No subject suffered choking when ingesting YG. The commercially available YG, products tested showed some differences in their mechanical and physical properties, which corresponded to the physical properties of commercially available baby foods commonly used during early to medium weaning periods. With augmented solidity stress, the adhesion of YG was revealed to be significantly enhanced but the agglutination to be significantly reduced.

【Discussion】This survey found that YG is ingested daily by handicapped children and thus it seemed to be an important food. In addition, it was found that the guardians generally recognized that the commercialy available YG products tested showed some differences in mechanical and physical properties, so it is necessary to choose the required conditions of YG which are appropriate for the oral function in handicapped children. In general, deglutition becomes difficult when the adhesion of food is enhanced and the agglutination is reduced. Because the adhesion of YG was revealed from this study to increase with further reduced agglutination in response to the augmented solidity stress, it is suggested that the solidity of YG could be used as an index of its mechanical/physical properties.

We report two cases of lateral medullary infarction (LMI) whose bolus was predominantly passed on the affected side at the cricopharyngeal portion on videofluorography. Both cases had a very similar lesion and similar atypical symptoms, Therefore, we considered the relationship between the lesion and symptoms of these cases.

Case one was a 62-year-old man whose MRI showed a lesion in the left lateral medulla (pontomedullary junction). His chief complaint was not being able to swallow saliva. Perception of pain and temperature was decreased on the entire right side of the face. Central facial nerve palsy was also observed on the left side. Oral feeding started again 12 days after the onset.

Case two was a 58-year-old man. After balloon angioplasty for severe stenosis of vertebral artery, he displayed severe dysphagia and inability to swallow saliva, central facial nerve palsy on the right side and hoarseness. Perception of pain and temperature was disturbed on left-side limbs, body and face. MRI on the day after the operation showed an infarction in the right lateral medulla (pontomedullary junction) and right cerebellum. He began oral feeding again after approximately one month.

MRI revealed a lesion in the upper lateral medulla in both cases. These cases with unilateral sensory defects were diagnosed as having involvement of the lateral spinothalamic tract and the ventral trigeminothalamic tract were implicated on clinical grounds. Concerning the central facial nerve palsy, we thought that some of the axons of the corticobulbar tract descending further ipsilaterally were damaged after decussation forward of the contralateral facial nucleus. The details of how the bolus passed on the affected side were unclear, but there was a possibility of some causal relation between the upper medullary lesion, and a bolus had predominantly passed on the affected side at the cricopharyngeal portion in these cases, because of lesion extensions were very similar. Therefore, perhaps the bolus laterality in these cases was one of the symptoms of LMI.

In a further study, we need to conduct a more detailed examination from various aspects about the relationship between laterality of bolus passage and medullary lesion.