Mikoto Baba

Chewing and food consistency: Effects on bolus transport and swallow initiation

Preswallow bolus formation usually occurs in the mouth for liquids and in the oropharynx for solid foods. We examined the effect of chewing on the relationship between bolus transport and swallow initiation. Fifteen healthy subjects were imaged with lateral projection videofluorography while eating liquids, solid foods, and a mixture of liquid and solid foods in upright and facedown postures. Videotapes were reviewed to measure the location of the leading edge of the barium at swallow initiation. Chewing and initial consistency each altered the relationship between food transport and swallow initiation. In particular, when chewing liquid (or consuming foods with both liquid and solid phases), a portion of the food commonly reached the hypopharynx well before swallow onset. This transport to the hypopharynx was highly dependent on gravity, but transport to the valleculae for chewed solid food was active, depending primarily on tongue-palate contact. Chewing appeared to reduce the effectiveness of the posterior tongue-palate seal, allowing oral contents to spill into the pharynx. Consuming two-phase foods with both solid and liquid phases may increase the risk of aspiration in dysphagic individuals with impaired airway protective reflexes.

What Is the Chin-down Posture? A Questionnaire Survey of Speech Language Pathologists in Japan and the United States

The “chin-down” or “chin-tuck” maneuver is a postural technique widely used in dysphagia treatment. The posture, however, does not have a precise anatomical definition. We studied the current practice of 42 speech-language pathologists (SLPs) in Japan and the U.S. with a questionnaire survey regarding the chin-down posture. The main findings were that (1) three of five of the pictures were selected by respondents both in Japan and in the U.S. as depicting the chin-down posture; (2) 23% of Japanese and 58% of the U.S. SLPs made a distinction between chin down and chin tuck; and (3) the use of anatomical terminology by SLPs differed between the two countries. This study showed that there is poor agreement among SLPs about the meaning of the chin-down and chin-tuck postures. Developing a precise definition is important because various postures may have differing physiologic effects.

Development of an easily swallowed film formulation

We have developed an easily swallowed film formulation that swells and turns into a jelly instantaneously upon absorption of a small amount of saliva. The formulations structure comprises a gelating layer on both faces of a drug-containing layer, and this structure restrains the elution of a drug in the mouth. Swelling experiments confirmed the instantaneous gelation when the gelating layer absorbs purified water. Fifteen seconds after immersion in purified water, the bulk modulus of the film formulation was less than 500N/m2, which is an appropriate value for easy swallowing by elderly people. A dissolution study confirmed the delayed dissolution of glimepiride as a model drug. In a clinical study, although the stagnation at the upper esophagus was observed with a gelatin capsule, the film formulation passed the esophagus and reached the stomach quickly.

Hyoid Bone and Larynx Movements During Electrical Stimulation of Motor Points in Laryngeal Elevation Muscles: A Preliminary Study

Objectives:  This study aimed to determine the laryngeal elevation muscle motor points, evaluate the movement of hyoid bone and larynx during stimulation of the motor points, and examine the potential for treating severe dysphagia by functional electrical stimulation.

Simple Swallowing Provocation Test Has Limited Applicability as a Screening Tool for Detecting Aspiration, Silent Aspiration, or Penetration

A number of tests for evaluating dysphagia without using videofluoroscopic examination of swallowing (VF) or videoendoscopic evaluation of swallowing (VE) have been developed. The simple swallowing provocation test (SSPT) is unique because it is performed while in a supine position and does not require the patient’s cooperation. However, whether the SSPT detects aspiration or penetration correctly is unclear because its validity determined by VF or VE has not been evaluated. Therefore, we determined the sensitivity, specificity, and predictive accuracy of SSPT followed by VF in 45 patients. The sensitivities of the first-step and the second-step SSPT for the detection of aspiration, silent aspiration, or penetration were 72–75% and 13–17%, respectively; the specificities of the first-step and the second-step SSPT were 38–44% and 80–89%, respectively; and the predictive accuracies of the first-step and the second-step SSPT were 58–67% and 31–49%, respectively. These data suggest that SSPT has limited applicability as a screening tool for aspiration, silent aspiration, or penetration because of its low sensitivity. This test may be useful for patients who cannot undergo other tests due to cognitive and/or linguistic dysfunction.

Dysphagia Rehabilitation in Japan

This article describes the features of Japanese dysphagia rehabilitation, particularly where it differs from that in the United States. Many kinds of professionals participate in dysphagia rehabilitation; nurses and dental associates take important roles, and the Japanese insurance system covers that. Videofluorography and videoendoscopy are common and are sometimes done by dentists. Intermittent catheterization is applied to nutrition control in some cases. The balloon expansion method is applied to reduce pharyngeal residue after swallowing. If long-term rehabilitation does not work effectively in dysphagia due to brainstem disorder, the authors consider reconstructive surgery to improve function.

Effects of Food Consistencies and Mastication on Bolus Transport and SwallowInitiation in Individuals with Hemispheric Stroke

Mastication and food consistency each affect the passage of food through the oral cavity and pharynx and its coordination with swallow initiation. Since hemispheric stroke may damage cortico-medullary neural pathways, we hypothesized that it could also alter the coordination of eating and swallowing. Using videofluorography, we studied 30 individuals with hemispheric stroke and 27 age-matched controls as they consumed liquid barium, corned beef hash, or a combination of liquid and solid (two-phase) food. We tracked the leading edge of the barium during feeding and at swallow onset in relation to occurrences of laryngeal penetration and aspiration. Compared with asymptomatic controls, the leading edge remained in the hypopharynx before swallowing longer in stroke subjects (P = 0.016) and was lower in the foodway at swallow onset with two-phase food (P = 0.03) and liquid (P = 0.06). Penetration-aspiration scores were significantly higher for liquid and two-phase ingesta when the leading edge was deeper in the pharynx at swallow onset (P = 0.03). These findings suggest that stroke alters the coordination of bolus transport and swallowing, particularly with foods containing a liquid phase. With such an impairment, a bolus may enter the hypopharynx prematurely, thus increasing the risk of aspiration.

Classification of sequential swallowing types using videoendoscopy with high reproducibility and reliability

ObjectiveThis study aimed to classify sequential swallowing types using videoendoscopy (VE) avoiding radiation exposure and compare the results using videofluoroscopy (VF). DesignTwenty-one healthy adults simultaneously underwent VF and VE during sequential straw drinking. Each discrete swallow was classified into an L-segmental type (laryngeal vestibule opens after swallow) or L-continuous type (laryngeal vestibule closure continues after swallow) using VF and a V-segmental type (velopharynx opens after swallow) or V-continuous type (velopharynx closure continues after swallow) using VE. Test-retest reproducibility and interrater and intrarater reliability were evaluated in ten healthy adults. ResultsOf 128 swallows, 94 were L-segmental and 34 were L-continuous types as per VF, whereas 95 were V-segmental and 33 were V-continuous types as per VE. The leading edge of the bolus at swallow onset was significantly deeper in L-continuous types (P = 0.001). Laryngeal vestibule closure on VF images corresponded to velopharyngeal closure on VE images for 127 of 128 swallows (&kgr; = 0.98, P < 0.001). All subjects showed the same types of swallows in the first and the second studies. Both interrater and intrarater reliability were high. ConclusionVE showed high reproducibility and reliability in the classification of sequential swallowing types.

An Investigation of the Oral Intake Recovery Rate as Defined by the 2014 Medical Treatment Reward Revision in Japan

Objective : The 2014 Medical Treatment Reward Revision in Japan newly defines the oral intake recovery rate and requires a change of more than 35% to calculate various additions and subtractions. We calculated the recovery rate in various diseases and clarified some inherent problems. Methods : From April 2012 to March 2014, we retrospectively investigated the age, sex, removal rate from nasal nutrition or gastric fistula, oral intake recovery rate and days until removal of 286 inpatients with nasal nutrition or gastric fistula for dysphagia. Results : The removal rates for stroke, brain injury, oral and laryngopharyngeal cancer and other diseases were nearly always more than 50% because the disease did not cause dysphagia directly or the rehabilitation was effective for treating the remaining dysphagia. But the removal rates for neurodegenerative disease, complications due to stroke and brain injury in the chronic phase and respiratory disease did not reach 35% because the previous dysphagia progressed or actualized. Almost all oral intake recovery rates did not extend to 35% for exclusion of oral intake recovery within one month. Conclusion : The criteria of oral intake recovery rate needs to be reviewed in respect to setting goals to match the patient’s underlying disease and to evaluate the possibility for early rehabilitation. ( Jpn J Rehabil Med 2015;52:713.719 ) 要 旨 目的:2014年度診療報酬改定により経口摂取回復率が新たに定義され,35%以上 であることが各種加算・減算要件で求められる.当院の経口摂取回復率を算出し問題点を検討 した.方法:2012年 4月~ 2014年 3月当院入院中,摂食嚥下障害に鼻腔栄養や胃瘻を導入し た 286例に関し,病態毎に年齢,性別,経管栄養からの離脱率,経口摂取回復率,離脱までの 日数を後方視的に調べた.結果:離脱率は,直接障害を来さない病態やリハが効果的な病態 (脳卒中,頭部外傷,口腔・咽喉頭癌)で概ね 5割を超えたが,障害が進行・顕在化する病態 (神経変性疾患,脳卒中・頭部外傷慢性期後遺症,呼吸器疾患)は 35%未満であった.経口摂 取回復率は,離脱率の分母分子から「1カ月以内に経口摂取に回復した」87例などが除外され ほぼ全て 35%未満となった.結論:現在の経口摂取回復率の基準は実状と乖離しており,病 態毎の目標設定や早期リハの評価に関し再検討すべきである.

The secretion severity rating scale: A potentially useful tool for management of acute phase fasting stroke patients

This study aimed to determine if performing fiber-optic endoscopic evaluation of swallowing (FEES) simultaneously with video fluoroscopic swallowing study (VFSS) improved detection of both dysphagia and anatomic and physiologic abnormalities of the pharynx and larynx. A total of 69 participants (47M, 22F, mean age = 64 years, range = 37–87 years), the majority of whom had a diagnosis of stroke (62%), were evaluated. FEES and VFSS were analyzed by two raters using a modified version of the Penetration-Aspiration Scale: levels 2 and 3 were combined for a new level 2, levels 4 and 5 were combined for a new level 3, and levels 6 and 7 were combined for a new level 4, for a total of 5 levels. Performing FEES simultaneously with VFSS increased both detection rates of pharyngeal residue, laryngeal penetration, tracheal aspiration, and anatomic abnormalities of the pharynx and larynx. Comment