【Objective】Dysfunction of pharyngeal clearance increases with age, so aspiration in elderly people shows higher development. The stylopharyngeus（SP）has been regarded as the main pharyngeal shortening muscle because of its longitudinal direction, and it is also suggested that the muscle serves to clear pharyngeal retention. In the present study, SP was examined to clarify the morphological characters of aspiration in the elderly.

【Materials and Methods】 169 left and right specimens obtained from 89 formalin-treated room cadavers were used. The dimensions of SP were measured and its cross sectional area was calculated. The insenion angle of SP to the pharyngeal wall and insenion frequency of SP to piriform recess was also measured. The cadavers were sorted by age：55 to 74（young-old）and 75 or older (old-old). Age, sex and right-and-left differences were found using the Bonferroni test and paired t-test.

【Results】SP was separated into three parts：upper, middle and lower bundle immediately after penetrating the pharyngeal wall. The upper muscle bundle was in a fundus of the palatine tonsil bed. The middle bundle accompanied the pharyngoepiglottic fold to the epiglottis. The lower bundle（91% in male and 88% in female）reached the base of piriform recess and was inserted into the lateral wall of thyroid cartilage.

In the insertion angle of SP, the right angle was significantly larger than that of left, and among females of the old‐old group it was significantly larger than among males. The cross sectional area of SP was significantly larger in the old-old group than in the young-old group.

【Discussion】It is widely known that the larynx descends after 70 years old, therefore, it is expected that during swallowing a larger load is added for laryngeal elevation than before swallowing. Our results showed that the insertion angle of SP of the male old-old group was significantly smaller than that of the female group, and the SP cross sectional area of the old-old group was significantly larger than that of the young-old group. It is suggested that, compared with females, the larynx descent width of males is larger, thus the enlargement of SP cross sectional area was due to work hypertrophy in the old-old group and SP contributed to pharyngeal clearance.

The aim of this study was to clarify the usefulness of some composite systems with multiple gelling agents and to suggest a new type of gelled foods designed for people with swallowing and mastication difficulties. The goal of the composite system was to recreate gelatin-like texture with enhanced setting rate and higher thermal stability than gelatin.

Agar, deacylated gellan gum, psyllium seed gum, and gelatin were used as gelling agents. Physical properties of these gels or gelled foods with these gelling agents were investigated by dynamic viscoelasticity measurements under a small deformation and by puncture tests under a large deformation. Water-holding capacity was also determined by the quantification of syneresis.

Composite gels from agar and psyllium, or gellan and psyllium, exhibited similar physical properties to those of gelatin but with higher thermal stability represented by a smaller temperature dependence of the elasticities. Furthermore, these gels were proved to be stable against storage without generating any marked syneresis.

It is generally recognized that agar or deacylated gellan gum forms brittle gels with observable syneresis, leading to low ability to forrn bolus in the mouth. Gels from psyllium seed gum, on the other hand, have superior water-holding capacity, but the texture is highly elastic and adhesive. This means that each ingredient cannot be used alone as the base material in food products. Our study suggested that the combination of multiple ingredients is an approach to attaining our goal.

Freeze-infusion is a method for controlling hardness of food materials while retaining their shape by injecting macerating enzymes into them at low pressure after defrosting. In this study, we developed this method for prevention of syneresis from softened diets using freeze-infusion.

After defrosting frozen bamboo shoots, a stirred solution containing raw starch and the macerating enzymes was infused into them at low pressure. Subsequently, the bamboo shoots were macerated by the enzyme reaction. They were then heated to neutralize the enzymes and gelatinization of starch.

The method was capable of infusing both raw starch and enzymes into bamboo shoots and preventing syneresis through gelatipization. The effect depended on the raw starch content. Infusion of raw starch into the diets did not influence the hardness.

The results suggest that the freeze-infusion rnethod of raw starch is useful for controlling syneresis. This method can enhance the value of food products for persons with swallowing disorders and those receiving nursing care.

【Objective】In order to estimate the radiation exposure doses to the examiner from the videofluoroscopic examination of swallowing, we conducted a dosimetric study by means of a man-shaped phantom and dosimeters.

【Methods】Simulating the lateral view examination setting, x-rays were emitted to the phantom and the radiation doses were measured at 32 locations with an ionization chamber type dosimeter. The radiation doses in the anterior-posterior view examination setting were also measured at one location. Measurements were also carried out in the settings where radiation protection devices were employed. In addition, the radiation dose to the examiner's hand placed in the x-ray field was estimated using thermoluminescent dosimeters attached to the surface of the phantom.

【Results】The effective dose rates to the examiner in the lateral view examination were 414 μSv/h when the dosimeter was placed 50 cm away from the phantom and 28.4 μSv/h when it was placed 200 cm away from the phantom. The dose rate in the anterior-posterior view examination was about 1.5 times as high as that in the lateral view examination. When a radiation protective apron and a radiation protective screen were used, the doses were reduced to one fifth and one thirty-sixth, respectively. The dose rate to the examiner's hand was approximately 54 μSv/sec.

【Discussion】Assuming that the average duration of radiation exposure for one examination is 5 minutes, the annual radiation exposure dose to the examiner would not exceed the legal dose limit for occupational radiation exposure, and in most cases, that for the general public. It is also suggested that the dose would be lower than the differences in natural environmental radiation exposure doses between various areas in the world and than the occupational radiation exposure dose to aircraft crew. However, it should be emphasized that it is essential to make every effort to minimize radiation exposure by, for example, utilizing radiation protective devices.

The guardians of 123 infants with autistic spectrum disorder from 3 years old to 6 years old (ASD infants) and 131 infants without apparent developmental problems in nursery (normal infants) filled out the questionnaire survey on meals. The questions were divided into two parts：one concerned the scenes of eating meals, and the other concerned their intake and mastication of foods. A comparative examination among ages was carried out, and the following results were obtained.

(1) Scenes of eating meals

We checked 6 items concerning the scenes of eating meals. Almost 60% of ASD infants at the age of 3 had some problems, the number of infants with problems increased at the age of 4 or 5 and even at the age of 6, more than half of them had some problems. More than half of them showed symptoms of not keeping still during meal time.

ASD infants showed symptoms of not eating when disrupted by a new place or new persons or without ordinary utensils. These symptoms seemed to be corrected by developmental education.

However, when eating only in their houses, symptoms seemed not to disappear in a short period when not eating at the fixed mealtime.

(2) Intake and mastication of foods

We checked 7 items concerning their intake and mastication of foods. 70 to 80% of ASD infants had some problems through all ages. ASD infants could not use their utensils for meals properly even after the age of 5. This problem disappeared after the age of 5 in normal infants. Stuffing food into the mouth, swallowing without proper mastication and pooling meals in their oral cavities seemed not to change in a short period.

(3) Relation between mental ability and feeding problems in ASD infants

Only one item about using utensils for meals properly seemed to be related to mental ability in ASD infants.

The guardians of 123 infants with autistic spectrum disorder from 3 years old to 6 years old (ASD infants) and 131 infants without apparent developmental problems in nursery (normal infants) filled out the questionnaire survey on meals. A comparative examination among ages was carried out, and the following results were obtained.

(1) The number of ASD infants who reject some foods absolutely is much higher than those of normal infants and also the numbers of foodstuffs and food articles which ASD infants reject were much higher than those of normal infants.

Almost 10 % of ASD infants refused to eat more than 21 kinds of foodstuffs or food articles in all ages. The most plausible reasons for refusal to eat in ASD infants were the appearance of the foodstuffs or food articles；on the contrary, those of normal infants were varied. The mental ability of ASD infants showed no significant differences in the number of foodstuffs and food articles they reject.

(2) Among ASD infants, 60% of them refused to eat some foods which they had eaten before or 53% of them started to eat some foods which they had refused before. Similar episodes in normal infants could be seen： 14 % of them refused to eat and 11 % started to eat. Episodes of refusal to eat in ASD infants were significantly more common in the retarded group than in the mentally normal group.

(3) There is a high possibility of natural improvement of such so-called unbalanced diet. This fact is very important in the developmental education of ASD infants.

The objective of this study was to investigate the measures to improve the quality of care for the frail elderly. We conducted a mail survey of people with ingestion and swallowing disorders and the situation of the care within geriatric health-care facilities in Nagano prefecture (response rate 57.5%, 46 facilities). The subjects included both resident patients and those admitted for a short-term stay within the facilities. Regarding people with ingestion and swallowing disorders, we investigated the type of nutritional management and the application of assistance for oral feeding. Regarding the situation of the care, we investigated how to decide the method of care, whether the facility offered a care program, whether reimbursement was requested under the Long-term Care lnsurance (LTCI) scheme, and the incidence of aspiration accidents. From the 46 facilities, a total of 3699 users were evaluated per day. The users were categorized into four classes as follows：Support Required and Care Level 1, 11.7% (432 persons)；Care Levels 2 and 3, 38.8% (1437 persons) ； Care Levels 4 and 5, 48.8% (1805 persons)；Others, 0.7% (25 persons). People aged 85 and over accounted for 56.0% (2071 persons) of users. Those requiring assistance/supervision for oral feeding accounted for 38.4% (1422 persons), and those with cognitive disorders necessitating this type of support accounted for 28.0% (1037 persons). People using tube-feeding accounted for 6.4% (238 persons). At 30 facilities (65.3%) the staff assessed the method of feeding care with a formal evaluation tool. Thirty-five facilities (76.1%) held a conference about the feeding problems of each case； 12 (26.1%) performed speech therapy for dysphagia； and regular dentistry was done at 8 facilities (17.4%). Screening for nutritional disorders was performed by recording the BMI in 42 facilities (91.3%).Thirty-eight facilities (82.6%) requested the benefits of nutritional management from LTCI. There were aspiration accidents at 20 facilities (43.5%) during a three-month period. To improve the quality of the care, we need to (1) improve the evidence to support the feeding activities of the elderly with dementia；(2) increase the number of the facilities where the staff assesses the method of feeding care with a formal evaluation tool and where conferences are conducted about feeding problems, dentistry, and professional swallowing training.

A 74-year-old man with severe swallowing disorders due to progressive supranuclear palsy (PSP) was admitted to our hospital. He had not taken food orally for about 4 months after the onset of aspiration pneumonia. Videofluorography (VF) showed impaired tongue motion and closure at the isthmus of fauces due to the soft palate contacting the root of the tongue. This closure made bolus transfer to the pharynx extremely difficult even in the reclined position. Other than delayed onset of the swallowing reflex, there were no other abnormal findings during the pharyngeal stage. A newly designed prosthesis was constructed to help restore soft palate elevation. This prosthesis differs from the palatal lift prosthesis (PLP) in that its function was not intended to correct nasopharyngeal closure, but rather to form a passage for the bolus between the soft palate and root of the tongue. Because it was difficult for the edentulous patient to retain the prosthesis, artificial teeth were fabricated. The prosthesis together with the soft palate dropped down upon mouth opening. Mediated by the artificial teeth, the prosthesis was then raised by the mandibular ridge in order to elevate the soft palate during mouth closing. Use of the prosthesis, placed at a 30-degree reclined position, made it possible for the patient to ingest sliced gelatin jelly. The range in the soft palate elevation was less using this prosthesis compared with that using the PLP, which prevented adverse effects during the pharyngeal stage of swallowing, as demonstrated by VF and patient symptoms. This prosthesis would be particularly beneficial for patients with bolus transfer impairment resulting from closure at the isthmus of the fauces due to soft palate malfunction, while preserving pharyngeal stage function. This newly designed prosthesis may serve a critical role in the treatment of patients with PSP in which this type of soft palatal malfunction is frequently reported.