Lewis Jones

Mastication and swallowing in patients with postirradiation xerostomia

PURPOSE Very little objective data has been reported on mastication and swallowing in xerostomic patients, which would substantiate presumed causal relationships between xerostomia and patient complaints. The purpose was to elucidate which components of mastication and swallowing were abnormal, and most directly related to xerostomia, and which appeared unaffected. METHODS AND MATERIALS A retrospective analysis of timing events in mastication and swallowing was done using videofluoroscopic data for 15 cancer patients with xerostomia, and 20 normal controls. Scintigraphy was also used to determine oropharyngeal residue after a water swallow. Cancer treatment modalities included radiation therapy or chemoradiation therapy. RESULTS For barium liquid and paste substances, timing measures were equivalent for controls and patients. Xerostomic patients took 46% longer to masticate a shortbread cookie, and timing for the initiation of swallowing was shorter, but duration of swallowing appeared unaffected. Oral and pharyngeal residues following the swallow were greater in the patient group. CONCLUSIONS Xerostomia primarily affected mastication and oral manipulation of a dry, absorbent food material. Increased oral and pharyngeal residues after a water swallow are ambiguously related to xerostomia. The initiation and duration of the pharyngeal swallow was not abnormal.

Normal adult swallowing of liquid and viscous material: scintigraphic data on bolus transit and oropharyngeal residues.

Scintigraphic data are provided for 20 normal control subjects, 39–65 years of age. Each subject swallowed 10 cc of water and 10 cc of a more viscous material (1,100 centipoise) consisting of apple juice thickened with Thick-It, a commercial food thickener. The test substances were combined with 2.5 mCi Tc-99m sulfur colloid. Scintigraphic data were acquired in dynamic mode for 10 sec at 25 frames/sec as the subjects swallowed. Time-activity (TA) data were used to compute transit times, percentage residues in the mouth and pharynx, percent ingested, and a derived swallow efficiency score. The liquid was ingested in a single swallow by all subjects, and 9 cc was actually tranferred to the esophagus. In contrast, for the viscous material, 11/20 subjects performed a second clearing swallow within the 10-sec interval. On the first swallow with the viscous substance, an average of 7 cc was transferred to the esophagus. Scintigraphy offers an excellent technique for determining natural and preferred volumes for swallowing a variety of bolus consistencies, since it can quantify the volume of each swallow or partial swallow. In this group of subjects the oral discharge time was shorter with the viscous material than with the water, but the pharyngeal transit times were not significantly different for the two bolus consistencies. Numerical efficiency scores were lower for the viscous material, indicating that such a measure is bolus dependent.

Aspiration in patients with head and neck cancer and tracheostomy

Tracheopulmonary aspiration is a common occurrence in patients with dysphagia associated with head and neck cancer. We performed quantitative scintigraphic analysis of tracheopulmonary aspiration in 125 patients with head and neck cancer; 58 of these patients had a tracheostomy. Tracheopulmonary aspiration occurred in 58% of patients with a tracheostomy and in 23% of patients without a tracheostomy. In six of seven patients with a tracheostomy, tracheopulmonary aspiration significantly increased when the obturator was removed and, in these patients, occlusion of the tracheostomy tube during feedings eliminated or reduced the complication. Our studies suggest that aspiration can be monitored accurately and conveniently by scintigraphy, and that this technique is useful in the evaluation and management of dysphagia in debilitated patients.

Pharyngeal transit time: Assessment with videofluoroscopic and scintigraphic techniques

The swallowing function of 31 normal and dysphagic subjects between the ages of 39 and 79 was tested with both videofluoroscopy and scintigraphy. Pharyngeal transit times for the pair of tests were compared. A statistically significant correlation of 0.66 was found. Normal pharyngeal transit time was under 1.2 s with either method, but mean values for scintigraphy were slightly longer than those for videofluoroscopy.

Sounds of swallowing following total laryngectomy

Accelerometer transduced sounds of swallowing in total laryngectomees did not show acoustical differences for liquid vs paste swallows, as are found in normals. Compared with normal swallows, tongue propulsion of the bolus in laryngectomee swallows occurred closer in time to a distinctive spectral change associated with bolus flow into the esophagus. Interpretation stressed the lack of mechanical traction from laryngeal elevation contributing to pharyngoesophageal sphincter opening, and the increased role of tongue propulsion in laryngectomee swallows.

Bolus propulsive activity of the tongue in dysphagic cancer patients

Videofluoroscopic recordings were analyzed for liquid swallows in dysphagic patients with cancer involving the pharynx. Temporal measurements were made for the tongue stripping action in relation to velar and hyoid function. Dysphagic subjects as a group displayed an altered sequence of activity compared to normal controls, with the onset of stripping occurring after velar closure. Tongue stripping action and hyoid movement appeared to be time-locked to a greater extent than tongue stripping and velar closure. Duration of the stripping gesture was longer in dysphagic patients than in normal controls.

Multiple swallows and piecemeal deglutition; observations from normal adults and patients with head and neck cancer.

The incidence of multiple swallows for liquid and paste, and the time delay between multiple swallows, was determined from videofluoroscopic records of modified barium swallow tests. In a comparison of liquid and paste, the overall incidence of multiple swallows did not differ, for either patients with head and neck cancer or normal controls. However, for liquid swallows the incidence in patients with cancer was abnormally high, predominantly in patients with pharyngeal cancer.

Scintigraphic quantification of pharyngeal retention following deglutition

A procedure is described for quantifying the amount of bolus material retained in the pharynx after completion of a swallow, using radionuclide swallow techniques. Data are derived from scintigraphic time-activity curves. The procedure takes into consideration the differential attenuation of radioactivity through various regions in the body, and expresses the result as a percentage of the total radioactivity in the ingested bolus. Illustrative examples are provided for swallows by normal individuals and patients with head and neck cancer.

Acoustic technique for determining timing of velopharyngeal closure in swallowing

A pure tone sound source was introduced at a nostril and monitored by a miniature accelerometer on the throat. During velopharyngeal closure in a swallow, the pure tone component in the accelerometer signal was attenuated. Throat accelerometer recordings were made simultaneously with videofluoroscopy of a modified barium swallow in adults with normal velopharyngeal mechanisms. It was verified that the period of sound attenuation corresponded to the period of velar closure. This noninvasive method of monitoring otherwise silent velopharyngeal closure holds promise for normative studies on swallowing function, as an adjunct method in longitudinal assessment, and as a training aid.

Acoustical manifestations of velopharyngeal closure during swallowing

In normal swallowing, velopharyngeal (VP) closure transienty isolates the nasopharynx from the aerodigestive tract for a period of approximately 700 ms. Although there are intrinsic sounds generated during swallowing that can be recorded from the throat surface [Hamlet et al., J. Acoust. Soc. Am. Suppl. 1 83, S23 (1988)], VP closure is ordinarily a silent event requiring special techniques for its acoustical detection. A 500‐ or 1000‐Hz tone is introduced into one nostril, and its presence is detected using a miniature accelerometer taped to the throat just below the angle of the mandible. During VP closure, there is attenuation of this component of the accelerometer signal recorded during swallowing. The onset of the period of attenuation corresponds to the onset of velar closure determined radiologically. The time of VP reopening can be detected with less certainty, possibly owing to resonance effects, and the position of the epiglottis and base of the tongue at that moment in some subjects. Medical app...