Pathophysiological Effect of Enlarged Adenoid on Middle Ear in Children

: Objective: To identify the incidence of otitis media with effusion (OME) in children with enlarged adenoid. Methodology: This is a cross sectional observational study was carried out at Department of Otolaryngology and Head Neck surgery of Sir Salimullah Medical College Mitford Hospital, Dhaka from July 2014 to June 2016. One Hundred and Fifty (150) children with enlarged adenoid were included in this study. All patients were subjected for history, local physical examination, evaluation of adenoid size by X ray of nasopharynx lateral view. Pure tone audiometry & tympanometry were done in all patients. Informations were recorded in a specially designed data collection sheet. Result: Among 150 children with enlarged adenoid 30(20%) patient had OME, majority of patients (60%) were age group 7-9 years. Male were predominant (60%) than female (40%). Among 150 patients grade-I was 16%, grade II-was 26%, grade-III was 54% and grade IV was 4%.According to the grading of enlarged adenoid cases , grade I, grade II , grade III and grade IV had 8.33%,15.38% ,23.46% and 50% cases had OME respectively. Hearing loss was in 33(22%) children. According to tympanometry, type A curve was in 118(78.67%) children, type B 26(17.33%) and type C 6(4%) children. Conclusion: Enlarged adenoid is associated with otitis media with effusion. Incidence of Otitis media with effusion increases with the proportion of severity of nasopharyngeal obstruction by enlarged adenoid


Introduction:
Lymphoid tissue in the submucosa of the roof of the nasopharynx called the pharyngeal tonsil.Excessive hypertrophy of this lymphoid tissue causes the pharyngeal tonsil to become enlarged; which is then commonly referred to as adenoids. 1By the age of 5 months adenoid can be identified in all children.Growth continues rapidly during infancy and plateaus between 2 and 14 years of age in most children.Regression of adenoid occurs rapidly after 15 years of age in most children.Adenoid appears to be at its largest in the 7 years age group. 2 The Adenoid Nasopharyngeal Ratio (ANR) is a more convenient radiologic parameter for determining whether adenoid hyperplasia is clinically significant or not, rather than the size of adenoid or the size of nasopharynx.ANR > 0.7 are considered to be the candidates for adenoidectomy. 3In a study it shows that children with adenoid obstruction is 7 times more risk of developing OME than that of normal non-adenoidal children. 4 The proportion of otitis media with effusion increases with the severity of nasopharyngeal obstruction by adenoid hypertrophy, and the most common type of tympanometry results seen among children with OME is type B. Grade III or more adenoid size of according to A/N ratio are mainly seen among patients having unilateral and bilateral OME, accounting for 16% and 37% of all cases with OME accordingly.In a study it was detected that 17.9% OME in children without complaints of hearing loss.Therefore, it is important to perform the middle ear examination and tympanometry in children before surgery even without parental suspicion of hearing loss. 7In ears with documented fluid, the average hearing loss is 20 decibels (dB),but may be as high as 50 dB.OME is diagnosed by otoscopy, pneumatic otoscopy and tympanometry. 8treated OME may result in serious consequences in the form of poor speech and intellectual development and permanent anatomical distortions within the middle ear cavity.Therefore, correct and early diagnosis and appropriate treatment of OME in children is imperative.

Study population
Children between 3-12 years old with enlarged adenoid attended to the department of Otolaryngology-Head and Neck Surgery, Sir Salimullah Medical College & Mitford Hospital, Dhaka.

Sampling technique
Purposive non randomized sampling method was used to select the sample.This purposive sampling was performed as per inclusion and exclusion criteria.

Inclusion criteria
Children of the age group of 3-12 years with enlarged adenoid attending in Department of Otolaryngology-Head and Neck Surgery, SSMC Mitford Hospital.

Exclusion criteria
• Children with conductive hearing loss other than enlarged adenoid (CSOM, wax etc.).
• Parents or legal guardians not willing to be included for the study.

Discussion:
The prevalence of adenoids is common in age group of 3 to 7 years. 9Because, in general, the normal adenoids attains their maximum size between the age of 3 and 7 years and then regress. 10As nasopharyngeal space gradually increase in size, but on other hand adenoids regress after 7 years; so the important factor in considering the harmful effects of the adenoids is not the absolute size, but more the size in relation to that of the nasopharynx.In this study about 60% having adenoids in the age group of 7 to 9 years (table I).Enlarged adenoids among 60% patients in 5 to 6 years old group in a study which is not concordance with us. 11nother study reported that large adenoids were most frequently observed between the ages of 6-8 years, this result is partially consistent with this study. 10garding degree of hearing loss6 (4%) children had moderate (41 -55 dB) and 27 (18%) children had mild hearing loss (26 -40 dB) (table III).The hearing loss was mild in 50.5% and moderate in 12.7% children in a study 5 .Our results also shows mild hearing loss patients are more than moderate hearing loss which is consistent with this result but total percentage of hearing loss is less because of gradual awareness and healthcare facility.
In our study according to size of adenoids, maximum children (54%) had grade-III followed by grade-II (26%) (table III).In one study shows that maximum children (54.2%) had grade-III followed by grade-II (16.7%),
Paradise et al study.In 6cases, clinically it was suspected fluid in the middle ear but after myringotomy, the fluid could not be detected.The reason lies behind recent onset of Eustachian tube blockage with enlarge adenoids.
We have found 30 (20%) of patient had OME due to adenoids which is consistent with another study ; where he showed 17.9% of the ears with OME due to adenoid hypertrophy were confirmed by myringotomy. 7r study showed a positive association between the degree of nasopharyngeal obstruction and the presence of OME.It was also found that there was an increase in the incidence of OME with the increase in the size of adenoids, as 50% with grade IV adenoids, 23.46% with grade III adenoids and 15.38% of grade II adenoids patients suffered from OME. Children with larger adenoids (grade IV) had more than four and two times the risk of developing OME than children with grade II and grade III nasopharyngeal obstruction respectively.

Conclusion:
Enlarged adenoid is associated with otits media with effusion (OME) in children.The larger the size of adenoids greater the degree of hearing loss.Increase severity of nasopharyngeal obstruction is directly associated with increased rate of OME. 7 Duration of the studyThe study period was 24 months, from July 2014 to June 2016.

Table IV :
Type of the curve according to tympanometry (N=150)