Changes in Swallowing After Anterior Cervical Discectomy and Fusion With Instrumentation: A Presurgical Versus Postsurgical Videofluoroscopic Comparison

Purpose The purpose of this study was to explore the impact of anterior cervical discectomy and fusion (ACDF) with anterior instrumentation on swallowing function and physiology as measured on videofluoroscopic swallowing studies. Method We retrospectively analyzed both functional measures (penetration-aspiration, residue) and physiological/anatomical measures (hyoid excursion, posterior pharyngeal wall thickness) in a series of 17 patients (8 men, 9 women, mean age 54 years). These measures were extracted from calibrated 5-ml boluses of thin radio-opaque liquids on both pre-ACDF and post-ACDF videofluoroscopies, thus controlling for individual variation and protocol variation. Results After ACDF surgery, we found significant within-subject worsening of Penetration-Aspiration Scale (Rosenbek, Robbins, Roecker, Coyle, & Wood, 1996) scores, vallecular (but not piriform sinus) residue, superior (but not anterior) hyoid excursion, and posterior pharyngeal wall thickness. Results are discussed in the context of previous literature. Conclusions ACDF surgery can affect both physiological/anatomical and functional measures of swallowing. Future research should expand to other biomechanical and temporal variables, as well as greater bolus volumes and a wider array of viscosities and textures.

S194 – Pharyngeal Thickness in Young and Elderly Normal Subjects

Objectives Previous research has demonstrated pharyngeal size and constriction differences between normal young and elderly adults. Evidence suggests that the pharynx of elderly subjects dilates and does not constrict as well as younger persons. The distance between the larynx and the hyoid at rest is greater in the elderly, as is the anterior-posterior width of the pharynx maximally expanded. We have noticed that the pharynx of elderly persons appears to atrophy with age. The purpose of this investigation was to compare pharyngeal wall thickness in young vs. elderly persons. Methods Videofluoroscopic swallow studies were performed on 82 normal adults under the age of 65 years and on 89 normal adults over the age of 65. Measures of posterior pharyngeal wall thickness (PWT) were determined at rest and at the same point during maximum constriction of the pharynx on a 20-cc bolus swallow. Data were compared with the independent samples t-test. Results No gender differences were identified for the younger or elderly groups. Mean PWT at rest was .40cm (± .08) for the younger group and 30cm (± .08) for the elderly (p <0.01). Pharyngeal wall thickness measured at the same point during maximum constriction was 1.08cm (±38) for the younger group and .92cm (±36) for the elderly (p <0.01). Conclusions Data from the current study suggest that the posterior pharyngeal wall is thinner in elderly individuals older than 65 as compared to younger adults. These differences may help explain differences in pharyngeal strength, swallowing efficiency, and safety in the elderly.