ABSTRACT
Objective To study the impact of changes in the pharynx on the vocal functions and resonance functions to evaluate the effects of UPPP on voice and in order to provide a reference for the selection of UPPP sur‐gery population .Methods The 30 male adult patients who underwent UPPP surgery were recorded pre-surgery ,1-week post-surgery and 3-month post-surgery speech .Then the multi-dimensional voice program (MDVP) , linear prediction coding (LPC) ,the Nasometer Ⅱ(model 6450) were used to evaluate the vocal functions ,the oral resonance functions and the nasal resonance function .Results F0 ,jitter ,shimmer ,and NHR were unchanged from the pre-surgery to the post-surgery condition .One week after the surgery ,F1 ,F2 of /a/,/i/and /u/were un‐changed (P>0 .05) .Three months after surgery ,F1 ,F2 of the vowel /a/and F1 of the vowel /u/were remained essentially unchanged (P>0 .05);while the frequency of F1 ,F2 of the vowel /a/and of F2 of the vowel /u/were significantly higher compared to pre-surgery values (P0 .05) .Three months after surgery ,the nasalance scores of the oral sentence and the oranasal sentence were unchanged (P>0 .05);while the nasalance scores of the nasal sentence were significantly higher compared to pre-surgery values (P<0 .05) .Conclu‐sion UPPP doses not affect the vocal function .But it might have a certain effect on resonance function ,demonstra‐ted by the change of several formant frequency and nasalance .UPPP in all professional voice users should be cau‐tious .Such patients who want to undergo UPPP must be informed of this potential modification of the voice after sursery .