Effect of Improved Nasal Airflow After Adenoidectomy on Nasal Erectile Tissue

ORIGINAL ARTICLE Effect of Improved Nasal Airflow After Adenoidectomy on Nasal Erectile Tissue

Carlos Alberto Carvalho Brinckmann, MD; Fla´via Penso Scapin, MD; Luiz Antoˆnio Guerra Bernd, MD, PhD; Jose´ Faibes Lubianca Neto, MD, PhD

Objective: To determine the effect of improved naso- the nasal turbinate region was considered (depth, pharyngeal airflow after adenoidectomy on nasal turbi- 2.20-5.40 cm). nate erectile tissue in pediatric patients. Results: The volume of the turbinate region varied from Design: Clinical, prospective, before-and-after study. 6.03 cm3 in the preoperative evaluation to 6.99 cm3 in the postoperative evaluation, representing an increase of Setting: Pediatric Otolaryngology Clinic at Hospital da 16% (PϽ.04). Multiple linear and logistic regressions did Crianc¸a Santo Antoˆnio de Porto Alegre (Complexo Hos- not reveal any factors other than adenoidectomy that could pitalar Santa Casa de Porto Alegre). explain this change.

Patients: Twenty-one 5- to 11-year-old children diag- Conclusions: Because the only possible explanation for nosed as having severe nasal obstruction, with an indi- the observed erectile tissue changes was improvement in cation for adenoidectomy. nasal airflow, we can assume that adenoidectomy favor- ably affects the behavior of nasal erectile structures and is Intervention: Adenoidectomy. associated with a decrease in turbinate size. Combined turbinate reduction and adenoidectomy should not be the rule Main Outcome Measures: Acoustic rhinometry because children may benefit from adenoidectomy alone. data before and 90 days after surgery. To specifically monitor erectile tissue behavior, only the volume of Arch Otolaryngol Head Neck Surg. 2008;134(8):832-836

ONAIRFLOW RHINITIS WAS pendent of afferent input from nasal air- initially described in pa- flow and that nasal airflow acts as a modu- tients who underwent lator rather than as an initiator of the laryngectomy and had cycling phenomenon. enlarged and sometimes Adenoid hyperplasia is one of the ma- violaceousN turbinates without any his- jor reasons for surgery in childhood, and tory of nasal disease or other situations that turbinate hypertrophy is a frequent asso- could justify such alterations.1 A possible ciated finding. For this reason, it is essen- triggering factor could be the change from tial that surgeons have a precise under- nasal breathing to tracheostoma breath- standing of the main cause of nasal Author Affiliations: Medical Sciences Graduate Program, ing. Cyclical temperature and humidity obstruction in each patient before a treat- Universidade Federal do Rio variations associated with the absence of ment decision is made. This may prevent Grande do Sul nasal airflow on nasal mucosa would trig- unnecessary surgery, thus reducing post- (Drs Brinckmann and Neto); ger a vasomotor reaction with loss of vas- operative morbidity and the risk of se- School of Medicine (Dr Scapin) cular tone, which would lead to turbi- quelae such as, in the case of turbinate sur- and Departments of nate enlargement. gery, atrophic rhinitis and nasal synechiae. Immunology (Dr Bernd) and The suggestion that the same phenom- We believe that simultaneous turbinate re- Ophthalmology and enon occurs in children with important na- duction with adenoidectomy is not re- Otolaryngology (Dr Neto), sal obstruction due to adenoid hyperpla- quired in children and that they may ben- Fundaçaõ Faculdade Federal de sia was first made by Ritter in 1970.2 efit from adenoidectomy alone. Cieˆncias Me´dicas de Porto Alegre; and Pediatric However, the hypothesis could not be con- In the past 2 decades, acoustic rhinom- Otolaryngology Division, firmed at the time because no appropri- etry has been used in studies involving na- Hospital da Criança Santo ate tests were available. In 1994, after the sal diseases and treatments, especially to Antoˆnio de Porto Alegre advent of acoustic rhinometry, Fisher et analyze nasal congestion in various situ- (Dr Neto), Porto Alegre, Brazil. al3 concluded that the nasal cycle is inde- ations.4-14 Acoustic rhinometry is a fast,

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©2008 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/30/2021 painless, and noninvasive diagnostic method that re- The surgical procedures were performed by otolaryngol- quires little collaboration from the patient.15 The test cal- ogy residents under the supervision of a single investigator culates cross-sectional areas at different points of the na- (J.F.L.N.), who revised all the cases at the end of surgery. All sal cavity, providing area and distance mapping, with the adenoidectomies were performed using a sharp curette and information on the location of sites with increased nar- without cauterization. Because the study objective was to observe the behavior of rowing, called minimum cross-sectional areas. It also pro- 7,8,16,17 erectile tissue after improved nasal airflow, the volume of the vides information on nasal volume. Some stud- region located at a nasal depth of 2.20 to 5.40 cm, defined as 4-6 ies have already used acoustic rhinometry to observe the turbinate region, was determined before vasoconstriction. nasal geometry changes after treatment of nasal obstruc- With children in this age group, the inferior turbinate head is tion. The objective of this study is to assess the effect of located deeper than 2 cm and the adenoid is located deeper than improved nasopharyngeal airflow after adenoidectomy 6.5 cm.6,15,21 To control possible distortions provoked by the on nasal turbinate erectile tissue in pediatric patients. nasal cycle, the volumes for the 2 nasal cavities were added. The paired-samples t test was used to analyze the difference between turbinate region volumes before and after surgery METHODS (⌬ turbinate region volume). Significance was established at PϽ.05. In addition, multiple linear and logistic regression mod- Twenty-one 5- to 11-year-old children were selected from the els were used to test the effect of sex, age, ethnic group, allergic outpatient clinic at the Hospital da Crianc¸a Santo Antoˆnio de Porto rhinitis, and size of adenoids on ⌬ turbinate region volume. Alegre Pediatric Otolaryngology Division between March 10, This project was approved by the research ethics commit- 2003, and December 18, 2006. All the children noted severe na- tee at Complexo Hospitalar Santa Casa de Porto Alegre. All the sal obstruction and had an indication for adenoidectomy. Pa- parents signed an informed consent form before their child tients with nasal obstruction from other causes, such as signifi- entered the study. cant septal deviation, nasal polyps, hypertrophy of palatine tonsils, and craniofacial malformations, were excluded from this study, RESULTS as were patients who received treatment for nasal obstruction 1 month before selection for the study. Patients with allergic rhinitis were not excluded, except those in whom the disease was Twenty-one children aged 5 to 11 years (mean [SD] age, not controlled. All the patients underwent a clinical evaluation 8.62 [1.83] years) were included in the study. Eleven with a complete otolaryngology examination, nasopharynx ra- (52%) were girls. Regarding ethnic group (skin color), diography, nasal endoscopy, skin tests for respiratory allergens, 10 children (48%) were white and 11 (52%) were non- and acoustic rhinometry. Radiography and endoscopy were used white. Skin test results were positive for respiratory al- to document the severity of adenoid obstruction and to control lergens in 9 (43%) of the patients. According to the ra- for the presence of associated nasal abnormalities. diographs, the adenoids were large in 16 (76%) of the In the analysis of radiographs, the adenoid to nasopharynx children and moderate in 5 (24%). Small adenoids were ratio was used to classify adenoids as small (ratios of 0.499- 0.624), moderate (0.625-0.731), or large (0.732-0.853).18 Na- not observed. On nasal endoscopy, 17 participants (81%) sal endoscopy analysis was based on the classification devel- had greater than 75% obstruction of the nasopharynx, oped by Wormald and Prescott,19 which defines small adenoids and in 4 participants (19%) the adenoid occupied 50% as occupying less than 50% the nasopharynx, medium ad- to 75% of the nasopharynx. No children had less than enoids as occupying 50% to 75% of the nasopharynx, and large 50% obstruction. The Figure compares turbinate re- adenoids as occupying more than 75% of the nasopharynx. Skin gion volume before and after surgery. An increase of 16% tests for respiratory allergens were performed to control for the in volume was noted (P=.04). This difference was not presence of allergic rhinitis. Acoustic rhinometry was per- explained by any of the study variables (sex, age, ethnic formed before and 90 days after surgery (SRE 2.100 rhinom- background, allergic rhinitis, and size of adenoids) ac- eter; RhinoMetrics A/S, Lynge, Denmark). The examinations cording to the linear and logistic regression models were performed following Standardization Committee on Acous- tic Rhinometry recommendations.20 The patient’s medical his- (Table 1 and Table 2). tory was recorded, and the otolaryngology examination was performed in the same room as the acoustic rhinometry, which COMMENT enabled a period of adaptation to the environment. This is an important aspect because nasal mucosal congestion is affected by changes in temperature and air humidity and by physical Nasal patency assessment is known for its complexity. activity (walking to the test location). Not even a combination of clinical history, nasal cavity The tests were performed with the patient sitting down, with examination, and allergic rhinitis investigation is suffi- the head resting on the back of the chair to prevent it from mov- cient to objectively and precisely describe the end point ing. Children with significant adenoid hyperplasia present more analyzed in this study, which aimed to demonstrate the nasal secretion, so all the patients were required to blow their impact of improved nasal airflow on nasal turbinate nose before the test. Participants with abundant rhinorrhea had erectile tissue. Acoustic rhinometry seems to be the their examinations postponed because nasal secretions affect ideal method for evaluating these changes because it is the accuracy of acoustic rhinometry. Three alternate measure- accurate and objective and can be easily performed in ments were performed on each side of the nasal cavity. If any children. errors were detected, the area-distance curve for the specific measurement was discarded and the mean of the remainders Previous studies have already used acoustic rhinom- was used. Fewer than 10% of measurements were discarded, etry in children undergoing nasal surgery. The results ob- and in no case were all 3 rejected. The most common prob- tained by those studies differ from the present findings, lems were caused by the patients moving their head or having possibly owing to differences in the samples, variations difficulty holding their breath during the examination. in the technique and equipment used, and the selection

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©2008 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/30/2021 14 Table 2. Multiple Logistic Regression Model of the Effect of Selected Variables on the Odds of Increasing P = .04 Nasal Turbinate Region Volume 12 Variable OR (95% CI) SD P Value

10 Sex 1.42 (0.15-13.28) 1.14 .76 Age 1.02 (0.56-1.84) 0.30 .96

3 Ethnic group 0.89 (0.07-10.77) 1.27 .93 8 Rhinitis 0.66 (0.08-5.58) 1.09 .70 6.99 A:N ratio 13.91 (0.01-Ͼ1000) 4.27 .54 Constant 0.27 4.96 NA 6.03 6

Nasal Volume, cm Nasal Volume, Abbreviations: A:N ratio, adenoid size to nasopharynx size ratio; CI, confidence interval; NA, not applicable; OR, odds ratio for the occurrence of 4 increase in turbinate region volume after adenoidectomy.

2 a nasal depth of 5.40 cm, excluding the nasopharynx region. Previous analyses of the effect of the nasal valve and 0 Before Adenoidectomy After Adenoidectomy the paranasal sinuses on the propagation of sound waves during acoustic rhinometry show that this procedure pre- Figure. Turbinate region volume variation before and after adenoidectomy in sents higher precision at a maximum nasal depth of 5 or the 21 study patients. The horizontal line in the middle of each box indicates 6 cm. According to these studies, the values obtained be- the median; the top and bottom borders of the box, the 75th and 25th yond this region are unreliable.15,24-26 Riechelmann et al27 percentiles, respectively; the whiskers above and below the box, the 90th and 10th percentiles, respectively; and the points beyond the whiskers, outliers. did not find any statistically significant differences when assessing the minimum cross-sectional area in the nasopharynx of children who underwent adenoidectomy, probably because they evaluated the posterior region of Table 1. Multiple Linear Regression Model of the Effect of Adenoidectomy on Turbinate Region Volumea the nose. Another reason might be the fact that they evalu- According to Selected Variables ated only the changes in minimum cross-sectional area. Discrete increases in cross-sectional area in several sites Variable b (95% CI) SD P Value of the nasal cavity may not be thought of as important changes in minimum cross-sectional area, although they Sex 0.68 (−1.48 to 2.84) 1.01 .51 Age 0.13 (−0.45 to 0.71) 0.27 .64 do result in a significant overall increase in nasal vol- Ethnic group −0.53 (−2.91 to 1.84) 1.11 .64 ume. Thus, an evaluation of changes in the whole tur- Rhinitis −0.74 (−2.78 to 1.29) 0.95 .45 binate region not restricted to a specific narrowing (tur- A:N ratio −0.16 (−7.37 to 7.06) 3.39 .96 binate head) should take into account the volume of the Constant 0.23 (NA) 4.19 NA region with the higher erectile tissue concentration instead of the minimum cross-sectional area. Similar to Abbreviations: A:N ratio, adenoid size to nasopharynx size ratio; b, effect 27 6 of variables on the ⌬ volume study; CI, confidence interval; NA, not Riechelmann et al, Marques and Anselmo-Lima did not applicable. find any statistical difference when they compared the a The ⌬ turbinate region volume is calculated as preoperative volume nasopharynx of children with adenoid hyperplasia be- minus postoperative volume at a nasal depth of 2.20 to 5.40 cm. fore and after surgery and in relation to a control group composed of nonobstructed children. Millqvist and Bende28 claim that acoustic rhinometry is a good method of different aspects for analysis in the rhinogram. Study- for monitoring the behavior of disease or the treatment ing children after nasal adenoidectomy, Kim et al4 showed effect in the individual patient but that it is less reliable an increase in nasal volume and in the cross-sectional area for comparison between patients. at the inferior turbinate head region. Later, Nigro et al5 Corey et al29 used acoustic rhinometry to compare the reported similar results. However, both studies in- nasal cavities in different ethnic groups. They found dif- cluded tonsillectomy associated with adenoidectomy, ferences only in the cross-sectional area of the nasal valve and acoustic rhinometry was performed on postopera- region, without any variation in nasal volume between tive day 15.5 There is evidence that simple tonsillec- ethnic groups. Trindade et al30 reported a difference in tomy can affect nasal physiologic features, decreasing na- nasal volume between females and males in the nasal valve sal resistence.22 The present study included patients who region, which became apparent in the turbinate region were admitted to the hospital exclusively for adenoid- only after mucosal vasoconstriction. That may explain ectomy, and acoustic rhinometry was performed 90 days the absence of difference in volume between boys and after surgery, allowing a longer period for adaptation of girls in the present study because we analyzed acoustic the nasal mucosa to the airflow. rhinometry data only before vasoconstriction in the tur- Fisher et al23 noted that acoustic rhinometry is not suf- binate region. In addition, the size of the present sample ficiently accurate to show alterations in the posterior na- may not have been sufficient to evidence the effect of the sal region. For this reason, these data were evaluated at variables on ⌬ turbinate region volume. Still, because the

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©2008 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/30/2021 results did not show any trend toward significance, it is The results suggest that combined turbinate reduction unlikely that a type II error occurred. and adenoidectomy should not be a rule because chil- This study shows a turbinate region volume varia- dren may benefit from adenoidectomy alone. tion from 6.03 cm3 preoperatively to 6.99 cm3 postop- eratively, which corresponds to an increase of 16% in the Submitted for Publication: June 3, 2007; final revision volume of the region with the highest amount of erec- received November 16, 2007; accepted December 14, tile tissue. The turbinate plays an important role in the 2007. sensation of nasal patency. Even discrete reductions may Correspondence: Carlos Alberto Carvalho Brinck- 31,32 10 result in significant relief. Hilberg et al, in 1995, mann, MD, Rua Ronald de Carvalho 57, Apt 502 Bairro showed that allergic patients had more variability in na- Mont Serrat, CEP 90450-220 Porto Alegre RS, Brazil sal volume than nonallergic patients. This was true even ([email protected]). in measures performed 15 minutes apart. Therefore, it Author Contributions: All authors had full access to all is reasonable to infer that longer intervals (eg, 3 months) of the data in the study and take responsibility for the could significantly affect measures. However, this does integrity of the data and the accuracy of the data analy- not seem to be the case in the present study because the sis. Study concept and design: Brinckmann, Bernd, and worsening of rhinitis in the postoperative period would Neto. Acquisition of data: Brinckmann and Scapin. Analy- lead to an increase in turbinate edema, decreasing (in- sis and interpretation of data: Brinckmann, Bernd, and Neto. stead of increasing) nasal volume. The inverse situation Drafting of the manuscript: Brinckmann, Scapin, Bernd, (ie, that patients were operated on at their worst rhinitis and Neto. Critical revision of the manuscript for impor- phase, so that the natural history of rhinitis or even the tant intellectual content: Brinckmann, Bernd, and Neto. biological phenomenon of regression to the mean would Statistical analysis: Brinckmann. Administrative, techni- explain the increase in nasal volume in the postopera- cal, and material support: Scapin, Bernd, and Neto. Study tive period) does not seem probable; all the patients were supervision: Brinckmann, Bernd, and Neto. extensively evaluated for rhinitis, and the procedure was Financial Disclosure: None reported. postponed in the presence of an acute rhinitis crisis. Also, acute inflammation is a contraindication to elective sur- REFERENCES gery and, thus, no patient would undergo surgery in this condition. 1. Fairbanks DNF. Nonallergic rhinitis. 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