Effects of changes in nasal volume on voice in patients after endoscopic endonasal transsphenoidal surgery

Objective: To investigate a potential correlation between changes in voice and changes in nasal volume. Methods: The endoscopic endonasal transsphenoidal approach (EETSA) was performed on 120 patients between February 2009 and August 2016 by using the bilateral modified nasoseptal rescue flaps method. All the patients were subjected to pre-and postoperative paranasal computed tomography (CT) and voice evaluations by using acoustic analyses, a nasometer to measure the nasalance, and determination of the voice handicap index (VHI). Paranasal CT and the medical image processing software were used to calculate changes in nasal cavity volume in three nasal sections. Results: Enlargement of the nasal cavity after surgery was evident in all three areas (anteronasal, p < 0.001; midnasal, p < 0.005; postnasal, p ≤ 0.025). In addition, EETSA resulted in significantly higher mean nasalance scores for the oronasal passage (p < 0.001) and nasal passage (p < 0.001); more frequency perturbation (jitter) (p < 0.001) and amplitude perturbation (shimmer) (p < 0.001); and higher grade, roughness, breathiness, asthenia, and strain scores (p < 0.001), and VHI (p < 0.01). However, only changes in the nasal volume after EETSA correlated with postnasal hypernasality (r < 0.2; p < 0.029). Conclusion: Although changes in nasal volume, voice, and speech may develop after EETSA, we found that changes in nasal volume were not correlated with changes in any voice-quality measure. However, the postnasal cavity was the region most dramatically affected by EETSA, and postnasal volume changes after surgery may be associated with hypernasal speech.