Manometric assessment of pharyngeal swallowing pressure after mandibular reconstruction

Oral cancer patients who undergo mandibular bone partial resection often exhibit swallowing disturbance after surgery. We examined the usefulness of manometry in obtaining quantitative data on swallowing function in patients after mandibular bone partial resection. Postsurgical swallowing function was investigated, using a combination of videofluorography (VF) and manometry, in five patients with oral cancer, who underwent mandibular bone partial resection. Three patients underwent reconstruction of soft tissue defects only, while the remaining two patients underwent reconstruction of both soft tissue defects and a bony segment using a reconstruction plate or vascularized fibula with a skin paddle. Oropharyngeal swallowing pressure ranged from 61 to 82 mmHg compared to the normal range of 109 ±31 mmHg (mean ± SD). Partial resection of the mandible without reconstruction of the bony segment defect had a negative effect upon oropharyngeal swallowing pressure. Four of the five patients exhibited normal function in the oral stage. Elevation of the larynx was disturbed in 80% of the patients. None of the patients in this study experienced aspiration after surgery. In conclusion, a combination of VF and manometry revealed that mandibular bone partial resection resulted in disturbed elevation of the larynx while pharyngeal swallowing pressure decreases in those patients who do not undergo bony segment reconstruction. Our results suggested that the tongue, including the base of the tongue, should be set in a closed space so that pharyngeal swallowing pressure does not release.