Alterations in white matter microstructural properties after lingual strength exercise in patients with dysphagia.

OBJECTIVES: Central nervous system effects of lingual strengthening exercise to treat dysphagia remain largely unknown. This pilot study measured changes in microstructural white matter to capture alterations in neural signal processing following lingual strengthening exercise. METHODS: Diffusion-weighted images were acquired from seven participants with dysphagia of varying etiologies, before and after lingual strengthening exercise (20 reps, 3×/day, 3 days/week, 8 weeks), using a 10-min diffusion sequence (9 b0, 56 directions with b1000) on GE750 3T scanner. Tract-Based Spatial Statistics evaluated voxel-based group differences for fractional anisotropy, mean diffusivity, axial diffusivity, radial diffusivity and local diffusion homogeneity (LDH). Paired t-tests evaluated treatment differences on each metric (P < 0.05). RESULTS: After lingual strengthening exercise, lingual pressure generation increased (avg increase = 46.1 hPa; nonsignificant P = 0.52) with these changes in imaging metrics: (1) decrease in fractional anisotropy, forceps minor; (2) increase in mean diffusivity, right inferior fronto-occipital fasciculus (IFOF); (3) decrease in mean diffusivity, left uncinate fasciculus; (4) decrease in axial diffusivity, both left IFOF and left uncinate fasciculus; (5) increase in LDH, right anterior thalamic radiation and (6) decrease in LDH, temporal portion of right superior longitudinal fasciculus. There was a positive correlation between diffusion tensor imaging metrics and change in lingual pressure generation in left IFOF and the temporal portion of right superior longitudinal fasciculus. CONCLUSIONS: These findings suggest that lingual strengthening exercise can induce changes in white matter structural and functional properties in a small group of patients with dysphagia of heterogeneous etiologies. These procedures should be repeated with a larger group of patients to improve interpretation of overall lingual strengthening exercise effects on cortical structure and function.

Effects of Device-Facilitated Isometric Progressive Resistance Oropharyngeal Therapy on Swallowing and Health-Related Outcomes in Older Adults with Dysphagia.

Swallowing disorders (dysphagia) are associated with malnutrition, aspiration pneumonia, and mortality in older adults. Strengthening interventions have shown promising results, but the effectiveness of treating dysphagia in older adults remains to be established. The Swallow STRengthening OropharyNGeal (Swallow STRONG) Program is a multidisciplinary program that employs a specific approach to oropharyngeal strengthening-device-facilitated (D-F) isometric progressive resistance oropharyngeal (I-PRO) therapy-with the goal of reducing health-related sequelae in veterans with dysphagia. Participants completed 8 weeks of D-F I-PRO therapy while receiving nutritional counseling and respiratory status monitoring. Assessments were completed at baseline, 4, and 8 weeks. At each visit, videofluoroscopic swallowing studies were performed. Dietary and swallowing-related quality of life questionnaires were administered. Long-term monitoring for 6-17 months after enrollment allowed for comparison of pneumonia incidence and hospitalizations to the 6-17 months before the program. Veterans with dysphagia confirmed with videofluoroscopy (N = 56; 55 male, 1 female; mean age 70) were enrolled. Lingual pressures increased at anterior (effect estimate = 92.5, P < .001) and posterior locations (effect estimate = 85.4, P < .001) over 8 weeks. Statistically significant improvements occurred on eight of 11 subscales of the Quality of Life in Swallowing Disorders (SWAL-QOL) Questionnaire (effect estimates = 6.5-19.5, P < .04) and in self-reported sense of effort (effect estimate = -18.1, P = .001). Higher Functional Oral Intake Scale scores (effect estimate = 0.4, P = .02) indicated that participants were able to eat less-restrictive diets. There was a 67% reduction in pneumonia diagnoses, although the difference was not statistically significant. The number of hospital admissions decreased significantly (effect estimate = 0.96; P = .009) from before to after enrollment. Findings suggest that the Swallow STRONG multidisciplinary oropharyngeal strengthening program may be an effective treatment for older adults with dysphagia.

Breath-group intelligibility in dysarthria: characteristics and underlying correlates.

PURPOSE: This study was designed to determine whether within-speaker fluctuations in speech intelligibility occurred among speakers with dysarthria who produced a reading passage, and, if they did, whether selected linguistic and acoustic variables predicted the variations in speech intelligibility. METHOD: Participants with dysarthria included a total of 10 persons with Parkinson's disease and amyotrophic lateral sclerosis; a control group of 10 neurologically normal speakers was also studied. Each participant read a passage that was subsequently separated into consecutive breath groups for estimates of individual breath group intelligibility. Sixty listeners participated in 2 perceptual experiments, generating intelligibility scores across speakers and for each breath group produced by speakers with dysarthria. RESULTS: Individual participants with dysarthria had fluctuations in intelligibility across breath groups. Breath groups of participants with dysarthria had fewer average words and reduced interquartile ranges for the 2nd formant, the latter a global measure of articulatory mobility. Regression analyses with intelligibility measures as the criterion variable and linguistic and acoustic measures as predictor variables produced significant functions both within and across speakers, but the solutions were not the same. CONCLUSIONS: Linguistic or acoustic variables that predict across-speaker variations in speech intelligibility may not function in the same way when within-speaker variations in intelligibility are considered.