الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 137 |  |  |
| | | from | 137 | | |
Abstract
Adenotonsillectomy is the most common surgery performed by otolaryngologists, especially in children. Among the most frequently voice concerns regarding this procedure are questions about changes in vocal patterns after surgery and whether they are temporary or permanent. Voice production corresponds to the physiological and physical processes by which vibration of the vocal fold is transformed into speech. The voice production organ has three subsystems:
1- A power source, constituted by the pulmonary system
2- A sound generator, typically the larynx; and
3- A sound modifier, the (pharyngeal, oral, and/or nasal) vocal tract.
In order to make quantitative voice evaluation, acoustic, aerodynamic, endoscopic, perceptual or patient-self assessment examination may be needed. If the diagnosis is not ambiguous, the methods can be combined.
Acoustic analysis is fundamental in order to characterize the extra-linguistic influence in the production of a particular speaker. Acoustic assessment aims to quantify and characterize the sonorous signal.
Resonance is described as the tendency of a system to vibrate (oscillate) with a larger amplitude at some frequencies than at others. Resonance, as it relates to speech, is the modification of phonated sound through selective enhancement of certain formant frequencies as opposed to others. This modification is determined by the size and shape of the cavities of the vocal tract.
The term dysphonia describes any impairment of the voice alteration in the sound of the voice with hoarseness, restriction of vocal performance, or strained vocalization.
Dysphonia, with the cardinal symptom of hoarseness, has a prevalence of around 1% among patients in general and a lifetime prevalence of approximately 30%.
The overall prevalence of dysphonia in children has been reported to be between 6 and 9%, but may be as high as 20% in some pediatric populations.
Our study is a prospective study that was done on fifty children ranging in age between 4-12 years, all the cases were indicated for adenotonsillectomy in the department of otorhinolaryngology El-Minia University hospital, the inclusion criteria was adenotonsillar hypertrophy.
All the patients were subjected to:
1- Full clinical history.
2- Clinical examination of head and neck, nose, nasopharnx, mouth, pharynx and mandible.
3- Radiological evaluation:
All study sample underwent standard lateral soft tissue X- ray on the nasopharynx 4- Audiotary perceptual assessment of voice and speech preoperatively and postoperative 1 month,3 months.
5- Acoustic analysis using computerized lab with MDVP program to register Fo, Jitter %, Shimmer db, HNR. Preoperative, post-operative 1month, 3 months. Data collection was carried out in a sound treated room during the morning and before 12 pm to avoid errors due to sound fatigue, using Multidimensional voice program software, at Phoniatrics Unit at Minia University Hospital. The microphone used was kept at a fixed distance of 10 cm in front of the subject’s mouth. We used the sustained vowels /a/e/u in a comfortable and habitual way, after deep inhaling.
The multi-dimensional voice profile, MVDP, provides a comprehensive analysis of continuous vowel sounds.
In order to analyze the samples, we used the time of 3-6 seconds, and irregularities in both the beginning and end of the vowel uttering were eliminated.
As regards acoustic analysis our results shows improvement of acoustic parameters fo, Jitter%, Shimmer db, HNR postoperatively i.e Fo shows significant difference at 1st month po1, while Fo,Jitter %, Shimmer db, HNR show significant difference after 3 months of operation . HNR shows non-significant difference postoperatively, but there is elevation values observed po2 this explained by the fact that dysphonia is accompanied by low HNR.
AS regards audiotary percepetual assessment of voice and speech our study shows improvement of dysphonia & hyponasality in comparison between preoperative and postoperative 1st and 3rd month.
We can emphasize that adenotonsillectomy can improve acoustic parameters, nasality and dysphonia within 3 months after surgery in children with hypertrophied tonsils and/or adenoids.