Diathermy versus surgical technique methods of adenotonsillectomy and its effect on voice in children

INTRODUCTION

The vocal tract, which starts from the glottis and extends to the lips is considered as resonator for speech production. Enlarged palatine tonsils may cause hypernasal speech, oral breathing or muffled voice ^(1,2).

The voice is basically a product of three physiological processes: 1) constant expiratory airflow controlled by chest muscles. 2) production of glottal sound through vibration of the vocal folds. 3) change in this sound with amplification and muffling of sound frequencies resulting from the action of pharyngeal, oral and nasal resonant structures (vocal tract) ^(3,4).

Adenotonsillectomy is the most common surgery performed by otolaryngologists especially in children. Among the most frequently voiced concerns regarding this procedure are questions about changes in vocal patterns after surgery and whether they are temporary or permanent. It is also reported that adenoid and tonsil hypertrophy cause obstruction of the nasopharyngeal region and a decreased mobility of velopharyngeal muscles (i.e. soft palate). Although it is the most studied, nasality is not the only form of voice alteration that can occur after adenotonsillectomy. With vocal tract modification, there can be changes in voice quality due to phonation instability as a consequence of changes in the vibration pattern of the vocal folds ⁽³).

There are number of techniques of tonsillectomy and can be grouped as cold and hot. Cold methods (No heat is used) include dissection, guillotine, partial tonsillectomy with microdebrider, harmonic scalpel, plasma mediated ablation and cryosurgery. Hot methods include electro cautery, laser, coblation and radio-frequency ^(5,6).

Common risks reported with these operations include but are not limited to bleeding, infection, and velopharyngeal insufficiency (VPI). VPI is defined as improper closure of the velopharyngeal sphincter during speech such that the soft palate is unable to reach the posterior and lateral aspects of the pharynx. Improper nasopharyngeal closure leads to hypernasal speech due to abnormal nasal air emission (NAE) andin some cases nasal regurgitation of food and beverages ^(7,8,9).

METHODS

Subjects and Study Design

The present study was done to evaluate surgical factors affecting speech and voice outcomes after adenotonsillectomy in pediatric patients .the study sample is composed of 100 children those were divided in two groups

Group 1 who composed of 50 child, they were operated by surgical cold dissection technique.

Group 2 who composed of 50 child, they were operated by bipolar diathermy

The study sample composed of 100 children all of them had adenotonsillar hypertrophy , group 1 were operated with surgical dissection 20 male (39.20%), 30 female (60.8%) and group 2 were operated with bipolar diathermy 27 male (57.4%), 23 female(42.6%) ranging in age (2-13).

Assessment method

All patients were subjected to

I Preliminary Diagnostic Procedures

1) Full E.N.T. history

Taking Recurrent attacks of tonsillitis at least seven episodes in the previous year, at least five episodes in each of the previous two years, or at least three episodes in each of the previous three years. Choronic tonsillitis causing persistent enlarged juglodiagastric lymph nodes, persistent hallitosis not responsive to medical treatment, septic focus, rheumatic fever or glomerulonephritis.

Nasal obstruction causing snoring and sleep apnea.

Adenoid facies

2) Full E.N.T. examination.

3) Subjective auditory perceptual assessment "APA" of both speech and voice .(preoperative and post-operative 1 month and post-operative 3 month )

II Clinical Diagnostic Aids:

1) Acoustic analysis:

This study aims to find out the results of measurement of fundamental frequency, jitter, shimmer and harmonic to noise ratio in children to  make accurate measurements of the proper voice in children for use in the diagnosis and follow-up the patient's voices before and after one month of surgery.

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.These vowels were analyzed as to their acoustic parameters: fundamental frequency (Hz), jitter (%), shimmer (dB) and noise-harmony ratio (NHR) (dB).

2) flexible fibro optic nasopharyngoscopy

RESULTS

The present study was done to evaluate surgical factors affecting speech and voice outcomes after adenotonsillectomy in pediatric patients .the study sample is composed of 100 children those were divided in two groups

Group 1 who composed of 50 child, they were operated by surgical cold dissection technique. Group 2 who composed of 50 child, they were operated by bipolar diathermy

• Descriptive :

Table 1: Distribution of age and sex of cases.

The study sample composed of 100 children all of them had adenotonsillar hypertrophy , group 1 were operated with surgical dissection 20 male (39.20%), 30 female (60.8%) and group 2 were operated with bipolar diathermy 27 male (57.4%), 23 female(42.6%) ranging in age (2-13)with Mean ± SD  7.3 ± 2.6 for group 1 and Mean ± SD 7.2 ± 2.3 as shown in table (1).

• Comparative study

Auditory perceptual assessment(APA) of voice :

Table 2 Distribution of the APA of voice

Statistical comparison between pre-operative, postoperative 1month and postoperative month 3 as regards auditory perceptual assessment of voice (APA of voice) insignificant differences were obtained between two groups as regard APA of voice as 

Preoperatively: there were 36 patients (70.6%) with no dysphonia,9 patients (19.6%) with dysphonia grade 1, 5 patients (9.8%) with dysphonia grade 2 were operated by surgical dissection as in group 1.

There were 35 patients (70%) with no dysphonia, 10 patients (20%)with dysphonia grade 1 ,5 patients (10%) with dysphonia grade 2 were operated by bipolar diathermy as in group 2.

There was insignificant difference were obtained between 2 groups as( p value 0.136)

Postoperatively 1 month: there were 39 patients (76.5%) with no dysphonia,9 patients with dysphonia grade 1,2 patients (3.9%) with dysphonia grade 2 were operated by surgical dissection as in group 1.

There were 37 patients (74%) with no dysphonia,11 patients (22%) with dysphonia grade 1 ,2 patients (2%) with dysphonia grade 2 were operated by diathermy as in group 2.

There was insignificant difference were obtained between 2 groups as(p value 0.999).

Postoperatively 3 month: there were 40 patients(78.4%) with no dysphonia,9 patients (19.6%) with dysphonia grade 1,2 patients (2%) with dysphonia grade 2 were operated by surgical dissection as in group 1.

There were 38 patients(76%) with no dysphonia ,10 patients (20%) with dysphonia grade 1,2 patients (4%)with dysphonia grade 2 were operated by diathermy as in group 2.

There was insignificant difference were obtained between 2 groups as (p value 0.829).

Table 3 Statistical comparison between pre-operative, postoperative 1month and postoperative month 3 as regards auditory perceptual assessment of voice (APA of voice)

As shown in table (3) and figure (1):

There is highly Statistical significant difference between preoperative and postoperative 1  month as regard APA of voice (p=0.001). There is highly Statistical significant difference between preoperative and postoperative 3 month as regard APA of voice (p<0.0001). There is Statistical insignificant difference between postoperative 1 month and postoperative 3 month as regard APA of voice (p=0.083)

Auditory perceptual assessment(APA) of speech

• resonance

Table 4 Distribution of resonance

Statistical comparison between pre-operative, postoperative 1month and postoperative month 3 as regards resonance.

Preoperatively, there were 4 patients (7.8%) with mild hyponasality,30 patients (6 0.8%) with moderate hypo nasality, 16 patients(31.4%) with severe hypo nasality were operated by surgical dissection as in group 1. There were 5 patients (10%) with mild hyponasality,30 patients (60%) with moderate hypo nasality, 15 patients(30%) with severe hypo nasality by bipolar diathermy as in group 2. There was insignificant difference were obtained between 2 groups as ( p value 0.928)

Postoperatively1month, there were 4 patients (8%) with normal nasality,33 patients(66%) with mild hypo nasality, 11patients(22%) with severe hypo nasality,1 patients (4%) slight hyper nasality were operated by surgical dissection as in group 1. There were 45 patients (90.2%) with normal nasality, 5 patients(60.8%) with mild hypo nasality, 15 patients(29.4%) with severe hypo nasality,1 patients (2%) slight hyper nasality were operated by bipolar diathermy as in group 2. There was insignificant difference were obtained between 2 groups as ( p value 0.8)

Postoperatively3month, there were 45patients (8%) with normal nasality,5 patients(9.8%) with mild hypo nasality were operated by surgical dissection as in group 1. There were 46 patients (92%) with normal nasality,4 patients(9.8%) with mild hypo nasality were operated by bipolar diathermy as in group 2. There was insignificant difference were obtained between 2 groups as ( p value 0.75)

Table 5

Statistical comparison between pre-operative, postoperative 1month and postoperative month 3 as regards resonance.

As regard resonance regardless the techniques. As shown in table (5), there is highly statistical significant difference between preoperative and postoperative 1 month as regard resonance (p<0.001).

There is highly statistical significant difference between preoperative and postoperative 3 month as regard resonance (p<0.0006). There is highly statistical significant difference between preoperative and postoperative 3 month as regard resonance (p<0.0001).

Acoustic analysis of voice

Statistical comparisons between pre-operative (pre), post-operative 1month (po1), post-operative 3 month (po2) as regards fundamental frequency (FO), jitter 1^st, shimmer db, harmonic noise ratio (HNR) are shown in table (10) between two groups.

Table 6 Distribution of acoustic analysis of voice

Statistical comparisons between pre-operative, post-operative 1month, post-operative 3 month as regard fundamental frequency (FO), jitter 1^st, shimmer db, harmonic noise ratio (HNR) between two groups.

Mann Whitney test for non- parametric quantitative data between the two groups

^a: p value > 0.05, ^b: p value <0.01, ^c: p value <0.001

The preoperative FO Mean ± SD  is 249±86.3 while the median is 259.7 while post operative1 Mean ± SD is 247.9t±86.5 the median is 255.6 while post operative2 Mean ± SD is 249±86.3 and the median is 259.7

Table 7

Statistical comparisons between pre-operative, post-operative 1month as regard fundamental frequency (FO), jitter 1^st, shimmer db, harmonic noise ratio (HNR) between two groups.

Mann Whitney test for non- parametric quantitative data between the two groups

^a: p value > 0.05, ^b: p value <0.01, ^c: p value <0.001

As table shown regardless type of techniques, there is highly statistical significant difference between preoperative and postoperative 1 month as regard F0 (p value <0.0001).There is highly statistical significant difference between preoperative and postoperative 1 month as regard jetter (p value <0.0001). There is highly statistical significant difference between preoperative and postoperative 1 month as regard shimmer (p value <0.0001). There is highly statistical significant difference between preoperative and postoperative 1 month as regard harmonic noise ratio (HNR) (p value <0.0001).

DISCUSSION

Palatine tonsils are located at the vocal tract, between the palatoglossal and palatopharyngeal arches. They are immunologically active lymphoid tissue that are part of the lymphoid system^(10,11). Thus, there are several quantitative studies on the effects of tonsillectomy on voice and speech reported in the literature. These studies mainly concentrate on the fundamental frequency and the first two to four formant frequencies of the vowels ^(12,13,14). Tonsils, however, decrease oropharyngeal airspace and may push the tongue forward. For this reason the effects of the tonsils’ motion and their interaction within the vocal tract may also influence consonants. Large tonsils could cause hypernasal speech, oral breathing, or muffled voice. When individuals produce  some sounds, the soft palate moves to touch the back of the throat which seals off the nasal cavity above from the oral cavity below. Large tonsils may prevent the soft palate from touching the back of the throat. For this reason, air escapes from the nasal cavity and causes hypernasal speech. The preoperative findings are not in agreement with The study by ^(1,15). Who related that the presence of hypertrophic tonsils reduces the oropharyngeal space, project the tongue forward and cause hypernasality, mouth breathing and muffled voice. In the present study, there was a statistical significant improvement in APA of voice (dysphonia) and APA of speech (hypo-nasality) at 1 and 3 months after adenotonsillectomy.

Our study revealed that for APA of voice Postoperatively 1 month there were 39 patients (76.5%) with no dysphonia,9 patients with dysphonia grade 1,2 patients (3.9%) with dysphonia grade 2 were operated by surgical dissection as in group 1. There were 37 patients (74%) with no dysphonia,11 patients (22%) with dysphonia grade 1 ,2 patients (2%) with dysphonia grade 2 were operated by diathermy as in group 2. There was insignificant difference were obtained between 2 groups as(p value 0.999). This could be explained as tonsillectomy and adenoidectomy do not directly affect the larynx and therefore should not influence the rate at which vocal folds open and close during sustained phonation. Which is agree with the study ⁽¹³⁾ believed that this observation is not surprising because tonsillectomy and adenoidectomy do not directly affect the larynx and therefore should not influence the rate at which vocal folds open and close during sustained phonation. These results indicate improvement of voice and speech of the patients by perceptual assessment of the voice and speech after adenotonsillectomy which in agreement with the study by ⁽¹⁶⁾ who indicated that Velopharyngeal insufficiency can exist without overt clefts of the hard or soft palate. The suspected causes are congenital short soft palate large nasopharynx, or both but in many cases neither can be anatomically established and the Velopharyngeal insufficiency must be considered idiopathic. These conditions often remain undetected until adenoidectomy deprives the patient of tissue mass in the nasopharnx and veloadenoidal closure. the study by ^(17,18) show adenoidectomy may affect voice resonance and nasalance, changing the shape and size of nasopharynx and upper respiratory tract, without any significant change in the voice quality.the earlier study by ⁽¹⁹⁾ reported that the most common observation in pathological conditions is a strong tendency for frequent and rapid changes in the regularity of the vibratory pattern, which are reflected acoustically as disturbances of F0^.(20)