Transoral surgery preserves good swallowing function in most cases, however, postoperative
dysphagia sometimes leads to fatal complication such as aspiration pneumonia. We investigated
the chronological changes in swallowing function have not been revealed relationship
with dysphagia. The primary aim of this study was to reveal the mechanism of dysphagia
following transoral surgery by analyzing chronological videofluorography (VF) findings.
Moreover, the secondary aim of this study was to evaluate the relationship between
mechanism of dysphagia and risk factors of patients to clarify the risk for dysphagia
lead to prevention of postoperative complications.
22 patients who underwent transoral videolaryngoscopic surgery (TOVS) for either supraglottic
or hypopharyngeal cancer were evaluated swallowing function. We performed VF during
the preoperative, postoperative acute, and stable phases and investigated the chronological
changes in the VF findings. The following parameters were evaluated by VF: horizontal
distance of laryngeal movement, vertical distance of laryngeal elevation, laryngeal
elevation delay time (LEDT), Bolus Residue Scale (BRS) scores, and Penetration Aspiration
Scale (PAS) scores. Additionally, we evaluated risk factors for postoperative aspiration
by investigating relationships between preoperative VF parameters, age of patients,
history of radiation therapy, resection area, tumor (T) stage, postoperative Numeric
Rating Scale (NRS), and PAS and BRS scores.
The median time at which oral feeding was resumed in this study was 9 (2–200) days.
The patients who had postoperative acute PAS scores of 4 and above exhibited delays
in resuming oral ingestion after surgery. TOVS did not impair laryngeal elevation
and LEDT; however, the BRS and PAS scores temporarily worsened in the acute phase
compared to the preoperative scores. These scores almost recovered to their preoperative
states in the stable phase, and both the BRS and PAS scores worsened and recovered
concurrently. Patients who exhibited poor vertical distance in laryngeal elevation
as observed via preoperative VF or who had histories of radiation therapy had worse
PAS scores in postoperative acute phase VF. Patients with broad resection areas had
worse BRS scores in postoperative acute phase VF.
TOVS didn't impair the function of laryngeal elevation and elicitation of the swallowing
reflex whereas pharyngeal bolus clearance, laryngeal penetration, and aspiration temporarily
deteriorated concurrently but eventually almost recovered to their baseline values.
Patients with histories of radiotherapy, poor laryngeal elevation, and broad resection
areas are at the risk of postoperative dysphagia after TOVS. Patients with these risk
factors need appropriate evaluation before resuming postoperative oral intake.