Ultrasound in dysphagia rehabilitation: a novel approach following partial glossectomy

Abstract

Purpose: While the presence of dysphagia following partial glossectomy has been widely reported, there is insufficient quality evidence to guide clinical decision making about the treatment of this disorder. This study investigated a novel dysphagia rehabilitation approach using ultrasound tongue imaging for patient training.

Method: Initially, a pilot study was conducted to investigate the feasibility of ultrasound visual feedback during swallow tasks. The protocol was then replicated using a single-case experimental designed study to investigate therapeutic effect. Swallow, speech, and oromotor functions were measured across multiple baselines using an A-B-A intervention study design.

Results: During intervention, both participants were able to interpret ultrasound tongue images during swallow tasks. Following intervention, positive therapeutic effect was achieved with reduced frequency of aspiration and self-initiated swallow strategies. Generalization of intervention was evidenced by reduced bolus transit duration on videofluoroscopy and improved functional oral intake scores. Speech and oromotor functions remained stable throughout the study demonstrating experimental control.

Conclusions: This study establishes that ultrasound visual feedback is feasible in dysphagia rehabilitation following partial glossectomy. In addition, the predicted therapeutic effect specifically to swallow but not speech or oromotor functions were demonstrated.

Implications for Rehabilitation

• Partial glossectomy results in altered tongue shape, movement, and function which negatively impact on speech and swallowing

• There is limited research evidence to support previously used speech pathology interventions (in particular, tongue range of movement exercises) to rehabilitate dysphagia following tongue cancer surgery

• The tongue, and hence oral phase of swallowing, can be viewed by placing an ultrasound probe under the chin

• Ultrasound scanning of the tongue is not invasive, can be repeated without dosage side effect. It’s also comfortable for the patient and if a portable probe and monitor are used, can be performed within a variety of clinical settings for assessment or therapy

• This study shows specific therapeutic benefit following ultrasound visual feedback along with a motor learning approach to rehabilitate swallow function following partial glossectomy

• Visual and verbal feedback that focus specifically on the motor movements undergoing adaptation (e.g., tongue wave movement, tongue elevation, bolus clearance) following partial glossectomy are recommended

• Patients who are able to see the ultrasound monitor, hear the feedback given, are cognitively able to self-evaluate tongue movement, and remember intervention goals will most benefit from ultrasound tongue visual feedback in therapy

• Clinicians also benefit from visualizing the tongue with ultrasound during assessment and therapy as a direct view reduces the subjectivity of rating task performance

Keywords:

• Deglutition
• deglutition disorders
• tongue cancer
• speech-language pathology
• intervention
• functional outcome

Acknowledgements

Thanks to Emma Charters, Eduarda Cunha, Elyse Green, and Danielle Stone for their assistance with reliability, fidelity, and data preparation. Thanks to Rob Heard for statistical support and Jill Clarke for training in ultrasound.

Disclosure statement

Blyth was supported by an Australian Post Graduate Award. Ballard is supported in part by an Australian Research Council Future Fellowship FT120100355. The authors have no financial or nonfinancial relationships to disclose. The authors alone are responsible for the content and writing of this paper. The authors report no conflicts of interest.