[Voice after supracricoid partial laryngectomy: comparison of two phonatory mechanisms]

Different laryngeal phonatory mechanisms may be observed at long term after supracricoid laryngectomy. For this study two mechanisms are differentiated. The "dilated" mechanism is the consequence of a forward movement of the neolarynx creating a new resonance cavity. The "contracted" mechanism tallies with the backward contraction of the base of the tongue and the contraction of the posterior pharyngeal wall compressing the neolarynx.

The aim of the study is to determine if the voice outcome is different between these two kinds of mechanisms.

The method is based on the selection of a homogeneous group: 12 patients operated by cricoepiglottopexy with a follow up superior to two years and with a stable voice and a full neoglottic closure during phonation. The voice quality and the phonatory mechanism are analysed. Regarding voice assessment, a self evaluation with the vocal handicap index adapted for the study and the GRBAS scale are carried-out. Frequency (usual, minimum, maximum, range) and loudness are used to appreciate the vocal capacities. The phonatory mechanism is studied by videolaryngostroboscopy, performed tongue free, with a normal /e/ and a high-low transition pitch.

The outcomes point out a difference between the two mechanisms. The best vocal results are observed in the "dilated" mechanism for the studied parameters and mainly for the frequency parameters.

The discovery of numerous phonatory mechanisms after supracricoid laryngectomy independent from neoglottic closure lead us to further studies of the impact of this type of surgery on articulatory patterns.