Expanding Instrumental Options for Dysphagia Diagnosis and Research: Ultrasound and Manometry

Abstract

Diagnostic assessment of swallowing in routine clinical practice relies heavily on the long-standing techniques of videofluoroscopic swallowing study (VFSS) and videoendoscopic evaluation of swallowing (VEES). These complementary and sophisticated techniques provide a real-time visualization of biomechanical movements of the structures involved in swallowing and consequent effects on bolus flow. Despite the sophistication of this instrumentation, interpretation relies heavily on subjective clinical judgement and temporal resolution is limited, limitations that may influence patient management. Adjunctive diagnostic assessments may be utilized to compensate for the limitations posed by VFSS and VEES. Ultrasound and pharyngeal manometry do not represent the latest in technological advances, with both emerging in swallowing research over 20 years ago. However, both have resisted integration into routine clinical practice, despite the fact that they offer quantitative metrics of swallowing that are not available using standard techniques. The aim of this review is to present recent research on these two less frequently used modalities in clinical swallowing assessment, discuss potential applications in clinical practice and review supportive data on test-retest reliability, rater reliability and validity. The paper will conclude with a case report that exemplifies the unique contribution of these modalities in executing and revising therapeutic approaches for a patient with neurogenic dysphagia.

Psychometric Properties of Visuoperceptual Measures of Videofluoroscopic and Fibre-Endoscopic Evaluations of Swallowing: A Systematic Review

“…Studies where measure/s required special software, such as computer programmes which calculate spatial or volume information using pixels, were excluded to better reflect current clinical practices. Although there are several software programmes available to assist recording analysis and offer a more objective interpretation of VFSS and FEES (29), they are limited in terms of clinical use due to the considerable time required to use the software (20). VFSS and FEES clinics typically see multiple patients consecutively due to limited availability of the equipment and various clinical staff required (30), making routine use of software difficult.…”

“…Two are widely considered 'gold-standards': the Videofluoroscopic Swallow Study (VFSS) and the Fibreoptic Endoscopy Evaluation of Swallowing (FEES) (19). The VFSS is the longest-standing instrumental assessment of dysphagia (20). It uses fluoroscopy, a continuous x-ray, to produce a greyscale 'movie' of the oropharynx and oesophagus during the swallowing act.…”

Structural Changes Following Velopharyngeal Resistance Training (Continuous Positive Airway Pressure Therapy)

“…Given the strong correlation between muscular hypertrophy and increased strength (eg, Young et al, 1983; Frontera et al, 1988; Young et al, 1985; Folland and Williams, 2007), most resistance training applications concerning the limb musculature have demonstrated training effectiveness using a functional (eg, strength) index as well as a morphologic (eg, muscle size) index as the primary outcome measures (eg, Young et al, 1983; Lüthi et al, 1986; Roman et al, 1993). Relatively little is understood regarding the effects of resistance training on head and neck muscles, which have different neural, structural, and functional organizations compared with limb muscles (Kent, 2004; Huckabee et al, 2015). Only a few morphologic indices (eg, lingual volume or suprahyoid muscle volume), along with functional outcome measures, have been incorporated into assessment of swallowing rehabilitative exercise applications (Robbins et al, 2005; Robbins et al, 2007; Carnaby-Mann et al, 2012; Kraaijenga et al, 2015).…”

Clinical Decision Making in Patients with Stroke-Related Dysphagia

“…The videoendoscopic evaluation of swallowing (VEES) may be preferred, however, for individuals who are medically fragile, ventilator dependent, or have contractures in which positioning would be problematic, as the testing equipment is portable, and the evaluation can be completed bedside. Moreover, VEES is an excellent follow-up assessment to document improvement in swallowing signs during 34 The protocol for the swallowing tasks in VFSS should be similar to the protocol used in the CSE in which various volumes, consistencies, and trials are tested. Unlike the CSE, the duration of the VFSS is restricted due to radiation exposure.…”