However, these changes in voice generally do not cause problems with speech function, researchers said. (Agencies)
Dr Kamran Khazaeni and colleagues of Mashhad University of Medical Sciences, Iran, said that patients considering rhinoplasty - especially those who use their voice professionally - should be aware of "potential voice alterations".
Researchers analysed changes in voice quality in 27 patients undergoing rhinoplasty at two hospitals in Iran.
The patients were 22 women and five men, their average age was 24 years. Twenty-two per cent of the patients used their voice professionally.
After rhinoplasty, patients completed a standard questionnaire to rate perceived problems with their voice.
In addition, recordings of the patients' voices made before and after rhinoplasty were compared by trained listeners, who were unaware of whether they were hearing the "before or after" recordings.
The questionnaire responses showed worsening in some areas of voice quality: particularly in the physical and emotional subscales, reflecting patients' perceptions of their voice and their emotional responses to it, researchers said.
There was no change on the functional subscale, reflecting the effects of voice on daily activities.
The trained listeners also perceived changes in voice quality, including an increase in "hyponasality" following rhinoplasty.
Hyponasal speech reflects the sound of the voice when not enough air is moving through the nasal cavity - for example, in a person with a stuffy nose.
"This observed increase in hyponasality perception demonstrates that the change in the patients' voices is perceptible to trained listeners, but does not address whether this change is apparent in everyday life and in routine conversations," according to Khazaeni and colleagues.
An acoustic analysis suggested changes in the frequency and amplitude of certain sounds, which may be related to narrowing of the nasal cavity after rhinoplasty.
"The changes in surface area of nasal cavity may increase airflow resistance and cause an increase in sound absorption and a decrease in passing sound amplitude," researchers said.
The study appears in the journal Plastic and Reconstructive Surgery, the official medical journal of the American Society of Plastic Surgeons (ASPS).
However, these changes in voice generally do not cause problems with speech function, researchers said.