Fiberoptic endoscopic evaluation of swallowing (FEES) in children with spinal muscular atrophy type 1: feasibility, swallowing safety and efficacy, and dysphagia phenotype

Purpose: Although dysphagia is a common symptom among patients with Spinal Muscular Atrophy Type 1 (SMA1), scant data exist on the application of Fiberoptic Endoscopic Evaluation of Swallowing (FEES) in this population. The aim was to analyze FEES feasibility, swallow safety and efficacy, dysphagia phenotype, and agreement with VideoFluoroscopic Swallow Study (VFSS) in children with symptomatic, medication-treated SMA1 and oral feeding. Methods: 10 children with SMA1 underwent FEES. Six patients had also a VFSS. Two clinicians independently rated FEES and VFSS videos. Swallowing safety was assessed using the Penetration-Aspiration scale (PAS). Dysphagia phenotypes were defined according to the classification defined by Warnecke et al. Swallowing efficacy was evaluated with the Yale Pharyngeal Residue Severity Rating Scale (YPRSRS) in FEES, whereas pharyngeal residue was rated as present or absent in VFSS. Results: FEES was performed in all children without complications. Four children tolerated bolus trials during FEES, in 4 children swallowing characteristics were inferred based on post-swallow residues, while 2 children refused to eat and only saliva management was assessed. The dysphagia phenotype of predominance of residue in the piriform sinuses was documented in 7/8 children. The PAS score was < 3 in 3 children and > 5 in one child. Swallowing efficacy was impaired in 8/8 children. VFSS showed complete agreement with FEES. Conclusions: FEES is a feasible examination in children with SMA1. Swallowing safety and efficacy are impaired in nearly all patients with strong agreement between FEES and VFSS. Dysphagia is characterized by the predominance of residue in the piriform sinus.