The medical treatment of secretory otitis media A clinical trial of three commonly used regimes By J. G. FRASER (London), MEHER MEHTA (Canterbury) and PATRICIA M. FRASER (London) Summary
A CLINICAL trial was undertaken to evaluate three medical treatments commonly used for chronic secretory otitis media. The treatments compared were Ephedrine nose drops, an oral antihistamine and decongestant (Dimotapp) and autoinflation of the middle ear. Changes in middle ear compliance and pressure were used as objective criteria of the efficacy of treatment in addition to changes in pure-tone threshold and to clinical assessment. Symptoms and abnormal signs tended to remit during the trial but there was no evidence from pure-tone audiometry and tympanometry that any of the treatments was beneficial. The period of observation enabled 28% of the children to avoid surgical treatment. Good and bad prognostic features are described which should help in deciding whether to manage a case conservatively or whether to proceed directly to surgery. Introduction
The problem of secretory otitis media has reached epidemic proportions in the United Kingdom and the United States (Shea, 1971). Using impedance audiometry Brooks (1969) has shown that 20% of five-year-olds have fluid-filled middle ears on entering infant schools. In our unit surgical treatment of this condition accounts for 60% of surgery on children under ten years of age. Many children develop a middle ear effusion with a coryza which resolves spontaneously as the infection subsides. In others, without infection, the fluid persists as a result of continued Eustachian tube dysfunction and gives rise to recurrent otalgia and conductive deafness which are sufficiently severe to warrant treatment. Many papers have been written on the surgical management of secretory otitis media, but a comparative clinical trial of the commonly prescribed medical treatments has not been reported. The object of this study was to fill that gap. At the same time it was hoped that a thorough evaluation of the history and physical signs might demonstrate good and bad prognostic features which would help in deciding whether to manage 757
J. G. Fraser, Meher Mehta and Patricia M. Fraser a case conservatively or proceed directly to surgery. The following treatments were used: Ephedrine nose drops 0-5% Ephedrine hydrochloride in 0-9% saline is a decongestant and vasoconstrictor which does not produce irritation nor harm the cilia (Fabricant, 1941). It is slower in producing its effects than adrenaline, but longer acting. Dimotapp Elixir According to Draper (1967) allergy is an important cause of secretory otitis media. In reviewing 340 allergic children he found that the incidence of secretory otitis media was more than twice that found in control cases. Miller (1970), measuring Eustachian tube function by manometry, found that 5 out of 13 children with chronic secretory otitis media responded to an oral decongestant (pseudo-ephedrine and carbinoxamine maleate) whereas none of 13 children responded to a placebo. Dimotapp is an antihistamine and a nasal decongestant. It is potent, with low toxicity and minimal side effects compared with other antihistamines (Thomas, 1958). Five ml of Dimotapp contain: Brompheniramine maleate Phenylephrine hydrochloride Phenylpropanolamine hydrochloride
4 mg 5 mg 5 mg.
Brompheniramine maleate belongs to the ethylenediamine group of antihistamines. It is a histamine antagonist, with feeble central effects. Phenylephrine hydrochloride is a powerful alpha-receptor stimulant. It is a vasoconstrictor agent. Phenylpropanolamine hydrochloride shows the pharmacological properties of ephedrine and is approximately equal in potency but causes less central nervous system stimulation. Autoinflation Inadequate ventilation of the middle ear cleft is the most important factor causing the persistence of fluid in the middle ear. Shea (1971) and Hunt-Williams (1968) felt that children could be taught to blow air into their middle ear to displace the fluid, a procedure which they describe as autoinflation. Method
New patients between 3 and 12 years of age with bilateral secretory otitis media were included in the trial. The diagnosis was confirmed in all cases by tympanometry as described by Brooks (1969). All cases had a 758
The medical treatment of secretory otitis media negative middle ear pressure in both ears and compliance less than o • 3 cc in one or both. Patients with higher compliance were included when a fluid level was seen and when one ear had definite fluid and the other a high negative pressure. Thus although some ears were not fluid-filled, all patients showed clear evidence of bilateral Eustachian tube dysfunction. The trial was designed to enable all three treatments to be tested at the same time (Doll, 1964). The method is illustrated in Table I. Patients are divided into 8 categories in each of which they receive one of the 8 possible combinations of three treatments. The allocation is restricted so that each successive group of 8 patients receives at random each of the 8 possible combinations. By the time, say, 80 patients have been treated, it is possible to compare the 40 patients who have received Ephedrine with the 40 patients who have not, each group being similar in respect of the proportion of patients who received the antihistamine or who were advised to autoinflate their ears. Similarly, one can divide the patients in two other ways and assess separately the effect of the antihistamine and of autoinflation. This design saves time and enables any interaction between treatments to be detected. The 0-5% Ephedrine nose drops were given twice a day. The parents were given verbal and written instructions to insert two drops into each nostril after placing the child supine with his head hanging over the side of the bed. This position was to be maintained for ten minutes after instilling the drops. The Dimotapp was given as 5 ml of the elixir three times a day. Autoinflation was taught in the way described by Hunt-Williams (1968). The children were shown in the clinic how to blow out a carnival blower with one nostril while closing the other with a finger and keeping the mouth shut. The relevance of the procedure was explained to the parents and they were provided with written instructions to carry out the TABLE I. DISTRIBUTION OF PATIENTS BETWEEN 8 COMBINATIONS OF 3 TREATMENTS
Treatment Combination
Dimotapp
Ephedrine
Inflation
+
+
-j-
o
o
+
I
_j-
2
4-
3 4 5 6 7 8
+
4o o o o
o
o
4-
+o o
Total
o 4o
Number of patients II II II
IO 10 II II
IO
85
+ Treatment given o Treatment withheld
759
J. G. Fraser, Meher Mehta and Patricia M. Fraser exercise twice a day. Once the child became proficient the paper part of the blower was replaced with a balloon to achieve higher intranasal pressure. They were reassured that 'popping' of the ears was an encouraging sign. The treatment was started after an initial assessment which included a clinical history and examination combined with pure-tone audiometry and tympanometry. All children were seen after three weeks to make sure that the treatment was being properly carried out. After six weeks, when treatment was stopped, the patients were seen again for a further clinical assessment combined with pure-tone audiometry and tympanometry. The clinical record included the symptoms and examination findings summarized in Table II and most are self-explanatory. The patient was recorded as having an inadequate airway when he had such a degree of nasal obstruction that he was unable to keep his mouth shut. A note was made if it were felt that adenoidectomy was indicated by the nasal symptoms and signs alone. The pure-tone threshold recorded before and after treatment was the average of the speech frequencies 500, 1,000 and 2,000 Hz. During TABLE II. SYMPTOMS AND SIGNS IN 85 CHILDREN AT INITIAL ASSESSMENT
Number
Characteristic Aural symptoms Deafness Otalgia Median no. of attacks Aural signs (both ears) Abnormal colour of ear drum Injection of ear drum Fluid level Atrophic ear drum Nasal symptoms Mouth breathing Snoring Speech hyponasality 'Runny' nose Nasal signs Mucosa swollen and pale Mucosa swollen and red Wet mucosa Airway inadequate
58 70
0/
/o
68-2 82-4 —
5 136 94
80-o
11 2
6-5
35 37 13 13 16
55-3 I -2
4
I-2
43-5 15-3 I5-3 18-8
9
IO'6
25 21
29-4 24-7
37
43-5
9
io-6
83
97-6 6o'O
A denoidectomy indicated
(i.e. two or more nasal symptoms and/or inadequate airway) History of allergy Throat
Tonsils present History of tonsillitis Median no. of attacks per year Tonsillectomy indicated (i.e. more than 5 attacks per year)
760
51 2 11
—
12-9
The medical treatment of secretory otitis media tympanometry the compliance of the middle ear and the middle ear pressure were recorded and any changes over the six weeks were used as objective criteria for assessing the results of the treatment. Results
Eighty-eight children were admitted to the trial and 85 completed their treatment as planned. There were 47 boys and 38 girls ranging in age from 3 to 12 years, with an average of 5-1 years. The distribution of patients between the eight combinations of treatment is shown in Table I. Table II summarizes the clinical characteristics of the patients at their initial assessment. The commonest presenting symptom was otalgia (82%), and deafness was reported in 68% of patients. In only 11% was there a history of allergy. It was felt that in nearly half the children (44%) adenoidectomy was indicated by their nasal symptoms alone. Pure-tone threshold and middle ear pressure recorded at the initial assessment followed a normal distribution. The mean pure-tone threshold was 26-7dB and the standard deviation 9-7 dB. The mean middle-ear pressure was —357 mm water, and the standard deviation 136 mm water. Compliance followed a log normal distribution with a mean of 0 • 19 cc. The comparability of patients in the groups which were to be compared after treatment was examined and no great differences were found between the patients in any of the groups. Clinical assessment of treatment
Abnormal aural signs showed a tendency towards remission, their prevalence being lower in all groups at the post-treatment assessment, but the tendency to improve was not related specifically to treatment with either Dimotapp, Ephedrine or autoinflation. Some patients had abnormal signs at the post-treatment assessment which had not been present initially. No combination of the three treatments was found to be more effective than any other in improving existing abnormal signs nor in preventing their occurrence. Indeed, the patients from whom all three treatments were withheld (combination 8) snowed as a group a similar tendency towards remission. The prevalence of nasal symptoms and abnormal signs showed a similar tendency to be lower at the post-treatment assessment, although again some children developed symptoms and signs for the first time during treatment. The change in the prevalence of mouth breathing, chronic snoring and speech hyponasality was negligible, but a swollen wet mucosa giving rise to an inadequate airway was recorded less frequently at the post-treatment assessment than at the initial visit. Although improvement in nasal symptoms and signs was recorded more often in the children treated with Dimotapp and/or Ephedrine nose drops, than in the children 761
J. G. Fraser, Meher Mehta and Patricia M. Fraser from whom both these treatments were withheld, the differences were not statistically significant (P>0-05). Pure-Tone Audiometry and Tympanometry
For every child the change between pre- and post-treatment values was calculated for each ear for pure tone threshold, middle ear pressure and compliance. The effect of each treatment was determined by comparing the mean change in children who had received the treatment with the mean change in those who had not. For each comparison a three-level analysis of variance was carried out, and Table III illustrates the method (Healy, 1972) with respect to the effect of Dimotapp on pure-tone thresold. The variation between patients is subdivided into a treatment effect and the residual difference between patients treated alike. The within-patient residual represents the variation in response between the ears of individuals. The variance ratio of 1-0775, which is obtained by testing the treatment mean square against the between-patient residual mean square, shows that treatment with Dimotapp has no significant effect on pure-tone threshold (P >o-O5). A t-test with degrees of freedom equal to those for patients within treatments gives the precise level of significance (Table IV). The variance ratio of the sources of residual variation, 2-2512, shows that, as might be expected, the variance between patients is significantly greater than the variation within patients (P
T
'°775
2-2512
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J. G. Fraser, Meher Mehta and Patricia M. Fraser observation was worthwhile. A tendency towards spontaneous remission was clearly demonstrated, and after the trial 24 of the 85 children (28%) were discharged from the clinic after being followed up for a year and having remained free of further trouble. In many clinics these children would have been treated surgically when the diagnosis of secretory otitis media was first made. Such unnecessary hospitalization of children can be avoided by careful observation for a few weeks before committing them to surgery. During this period of observation it would be reasonable to treat those children with definite signs or symptoms of nasal allergy either with an antihistamine such as Dimotapp, or with ephedrine nose drops, even though we have shown no improvement in Eustachian tube function with these treatments. The other 61 children in our trial (72%) did come to surgery, which consisted of myringotomies with insertion of ventilation tubes combined with adenoidectomy or adenotonsillectomy. By looking back at the initial history and clinical findings and comparing the children who recovered with those who needed surgery, good and bad prognostic features were identified. These features should help to decide whether to manage a case conservatively or whether to proceed to surgery. A notable finding was that those children who were found to be 'catarrhal' on first examination, with wet, swollen nasal mucous membrane all came to surgery eventually in spite of some improvement during treatment. Children with otalgia fared better than those without. Indeed, not one child who presented with deafness without otalgia recovered on conservative measures. All of the cured group had had otalgia, whereas only 75% of the failed group had earache. This may be a reflection of the fact that it is changes in Eustachian function and middle ear pressure that produce the pain, or perhaps that those children without pain present later. These were the only two factors which we found to have prognostic significance. However, it may be of interest to mention some of the other features examined which might have been expected to affect the outcome, but which failed to do so. Those children with symptoms of nasal obstruction did no worse than those without. Neither the length of history of deafness, nor its intermittent or continuous nature, was related to recovery. Observation of the colour of the drum was of no value. Pure-tone audiometric threshold was no guide to prognosis. Perhaps most disappointing was the fact that tympanometry did not help in selecting a group with a good chance of remission. It is to be hoped that an effective medical treatment for this common condition will be found. Since the medical treatments we used were found to be ineffective, it would be ethical in any future therapeutic trial to compare a group of children having therapy with a group having none. 764
The medical treatment of secretory otitis media Acknowledgements We wish to thank our audiometricians, Miss M. Slemeck and Miss S. MacDonald, for the care given to so much extra work, and Miss C. Jarvis for her generous secretarial help. The work was supported by a grant from the Rockefeller Research Committee of University College Hospital Medical School, and by A. H. Robins Ltd. REFERENCES BROOKS, D. N. (1969) The use of the electro-acoustic impedance bridge in the assessment of middle ear function. Journal of International Audiology, 8, 563. DOLL, R. (1964) Medical treatment of gastric ulcer. Scottish Medical Journal, 9, 183. DRAPER, W. L. (1967) Secretory otitis media in children: A study of 540 children. Laryngoscope, 77, 636. FABRICANT, H. D. (1941) Significance of the pH of nasal secretions in situ. Archives of Otolaryngology, Chicago, 34, 302. HEALY, M. J. R. (1972) Animal Litters as Experimental Units. Journal of the Royal Statistical Society Series C {Applied Statistics), 21, 155. HUNT-WILLIAMS, R. (1968) A method for maintaining middle ear ventilation in children. Journal of Laryngology and Otology, 82, 921. MILLER, G. F. (1970) Influence of an oral decongestant on Eustachian tube function in children. Journal of Allergy, 45, 187. SHEA, J. J. (1971) Autoinflation treatment of serous otitis media in children. Journal of Laryngology and Otology, 85, 1254. THOMAS, J. WARRICK (1958) Para-Bromdylamine Maleate (Dimetane). A clinical evaluation: Report of 140 cases. Annals of Allergy, 16, 128. The Royal Ear Hospital, Huntley Street, London WCiE 6AU.
765
A CLINICAL trial was undertaken to evaluate three medical treatments commonly used for chronic secretory otitis media. The treatments compared were Ephedrine nose drops, an oral antihistamine and decongestant (Dimotapp) and autoinflation of the middle ear. Changes in middle ear compliance and pressure were used as objective criteria of the efficacy of treatment in addition to changes in pure-tone threshold and to clinical assessment. Symptoms and abnormal signs tended to remit during the trial but there was no evidence from pure-tone audiometry and tympanometry that any of the treatments was beneficial. The period of observation enabled 28% of the children to avoid surgical treatment. Good and bad prognostic features are described which should help in deciding whether to manage a case conservatively or whether to proceed directly to surgery. Introduction
The problem of secretory otitis media has reached epidemic proportions in the United Kingdom and the United States (Shea, 1971). Using impedance audiometry Brooks (1969) has shown that 20% of five-year-olds have fluid-filled middle ears on entering infant schools. In our unit surgical treatment of this condition accounts for 60% of surgery on children under ten years of age. Many children develop a middle ear effusion with a coryza which resolves spontaneously as the infection subsides. In others, without infection, the fluid persists as a result of continued Eustachian tube dysfunction and gives rise to recurrent otalgia and conductive deafness which are sufficiently severe to warrant treatment. Many papers have been written on the surgical management of secretory otitis media, but a comparative clinical trial of the commonly prescribed medical treatments has not been reported. The object of this study was to fill that gap. At the same time it was hoped that a thorough evaluation of the history and physical signs might demonstrate good and bad prognostic features which would help in deciding whether to manage 757
J. G. Fraser, Meher Mehta and Patricia M. Fraser a case conservatively or proceed directly to surgery. The following treatments were used: Ephedrine nose drops 0-5% Ephedrine hydrochloride in 0-9% saline is a decongestant and vasoconstrictor which does not produce irritation nor harm the cilia (Fabricant, 1941). It is slower in producing its effects than adrenaline, but longer acting. Dimotapp Elixir According to Draper (1967) allergy is an important cause of secretory otitis media. In reviewing 340 allergic children he found that the incidence of secretory otitis media was more than twice that found in control cases. Miller (1970), measuring Eustachian tube function by manometry, found that 5 out of 13 children with chronic secretory otitis media responded to an oral decongestant (pseudo-ephedrine and carbinoxamine maleate) whereas none of 13 children responded to a placebo. Dimotapp is an antihistamine and a nasal decongestant. It is potent, with low toxicity and minimal side effects compared with other antihistamines (Thomas, 1958). Five ml of Dimotapp contain: Brompheniramine maleate Phenylephrine hydrochloride Phenylpropanolamine hydrochloride
4 mg 5 mg 5 mg.
Brompheniramine maleate belongs to the ethylenediamine group of antihistamines. It is a histamine antagonist, with feeble central effects. Phenylephrine hydrochloride is a powerful alpha-receptor stimulant. It is a vasoconstrictor agent. Phenylpropanolamine hydrochloride shows the pharmacological properties of ephedrine and is approximately equal in potency but causes less central nervous system stimulation. Autoinflation Inadequate ventilation of the middle ear cleft is the most important factor causing the persistence of fluid in the middle ear. Shea (1971) and Hunt-Williams (1968) felt that children could be taught to blow air into their middle ear to displace the fluid, a procedure which they describe as autoinflation. Method
New patients between 3 and 12 years of age with bilateral secretory otitis media were included in the trial. The diagnosis was confirmed in all cases by tympanometry as described by Brooks (1969). All cases had a 758
The medical treatment of secretory otitis media negative middle ear pressure in both ears and compliance less than o • 3 cc in one or both. Patients with higher compliance were included when a fluid level was seen and when one ear had definite fluid and the other a high negative pressure. Thus although some ears were not fluid-filled, all patients showed clear evidence of bilateral Eustachian tube dysfunction. The trial was designed to enable all three treatments to be tested at the same time (Doll, 1964). The method is illustrated in Table I. Patients are divided into 8 categories in each of which they receive one of the 8 possible combinations of three treatments. The allocation is restricted so that each successive group of 8 patients receives at random each of the 8 possible combinations. By the time, say, 80 patients have been treated, it is possible to compare the 40 patients who have received Ephedrine with the 40 patients who have not, each group being similar in respect of the proportion of patients who received the antihistamine or who were advised to autoinflate their ears. Similarly, one can divide the patients in two other ways and assess separately the effect of the antihistamine and of autoinflation. This design saves time and enables any interaction between treatments to be detected. The 0-5% Ephedrine nose drops were given twice a day. The parents were given verbal and written instructions to insert two drops into each nostril after placing the child supine with his head hanging over the side of the bed. This position was to be maintained for ten minutes after instilling the drops. The Dimotapp was given as 5 ml of the elixir three times a day. Autoinflation was taught in the way described by Hunt-Williams (1968). The children were shown in the clinic how to blow out a carnival blower with one nostril while closing the other with a finger and keeping the mouth shut. The relevance of the procedure was explained to the parents and they were provided with written instructions to carry out the TABLE I. DISTRIBUTION OF PATIENTS BETWEEN 8 COMBINATIONS OF 3 TREATMENTS
Treatment Combination
Dimotapp
Ephedrine
Inflation
+
+
-j-
o
o
+
I
_j-
2
4-
3 4 5 6 7 8
+
4o o o o
o
o
4-
+o o
Total
o 4o
Number of patients II II II
IO 10 II II
IO
85
+ Treatment given o Treatment withheld
759
J. G. Fraser, Meher Mehta and Patricia M. Fraser exercise twice a day. Once the child became proficient the paper part of the blower was replaced with a balloon to achieve higher intranasal pressure. They were reassured that 'popping' of the ears was an encouraging sign. The treatment was started after an initial assessment which included a clinical history and examination combined with pure-tone audiometry and tympanometry. All children were seen after three weeks to make sure that the treatment was being properly carried out. After six weeks, when treatment was stopped, the patients were seen again for a further clinical assessment combined with pure-tone audiometry and tympanometry. The clinical record included the symptoms and examination findings summarized in Table II and most are self-explanatory. The patient was recorded as having an inadequate airway when he had such a degree of nasal obstruction that he was unable to keep his mouth shut. A note was made if it were felt that adenoidectomy was indicated by the nasal symptoms and signs alone. The pure-tone threshold recorded before and after treatment was the average of the speech frequencies 500, 1,000 and 2,000 Hz. During TABLE II. SYMPTOMS AND SIGNS IN 85 CHILDREN AT INITIAL ASSESSMENT
Number
Characteristic Aural symptoms Deafness Otalgia Median no. of attacks Aural signs (both ears) Abnormal colour of ear drum Injection of ear drum Fluid level Atrophic ear drum Nasal symptoms Mouth breathing Snoring Speech hyponasality 'Runny' nose Nasal signs Mucosa swollen and pale Mucosa swollen and red Wet mucosa Airway inadequate
58 70
0/
/o
68-2 82-4 —
5 136 94
80-o
11 2
6-5
35 37 13 13 16
55-3 I -2
4
I-2
43-5 15-3 I5-3 18-8
9
IO'6
25 21
29-4 24-7
37
43-5
9
io-6
83
97-6 6o'O
A denoidectomy indicated
(i.e. two or more nasal symptoms and/or inadequate airway) History of allergy Throat
Tonsils present History of tonsillitis Median no. of attacks per year Tonsillectomy indicated (i.e. more than 5 attacks per year)
760
51 2 11
—
12-9
The medical treatment of secretory otitis media tympanometry the compliance of the middle ear and the middle ear pressure were recorded and any changes over the six weeks were used as objective criteria for assessing the results of the treatment. Results
Eighty-eight children were admitted to the trial and 85 completed their treatment as planned. There were 47 boys and 38 girls ranging in age from 3 to 12 years, with an average of 5-1 years. The distribution of patients between the eight combinations of treatment is shown in Table I. Table II summarizes the clinical characteristics of the patients at their initial assessment. The commonest presenting symptom was otalgia (82%), and deafness was reported in 68% of patients. In only 11% was there a history of allergy. It was felt that in nearly half the children (44%) adenoidectomy was indicated by their nasal symptoms alone. Pure-tone threshold and middle ear pressure recorded at the initial assessment followed a normal distribution. The mean pure-tone threshold was 26-7dB and the standard deviation 9-7 dB. The mean middle-ear pressure was —357 mm water, and the standard deviation 136 mm water. Compliance followed a log normal distribution with a mean of 0 • 19 cc. The comparability of patients in the groups which were to be compared after treatment was examined and no great differences were found between the patients in any of the groups. Clinical assessment of treatment
Abnormal aural signs showed a tendency towards remission, their prevalence being lower in all groups at the post-treatment assessment, but the tendency to improve was not related specifically to treatment with either Dimotapp, Ephedrine or autoinflation. Some patients had abnormal signs at the post-treatment assessment which had not been present initially. No combination of the three treatments was found to be more effective than any other in improving existing abnormal signs nor in preventing their occurrence. Indeed, the patients from whom all three treatments were withheld (combination 8) snowed as a group a similar tendency towards remission. The prevalence of nasal symptoms and abnormal signs showed a similar tendency to be lower at the post-treatment assessment, although again some children developed symptoms and signs for the first time during treatment. The change in the prevalence of mouth breathing, chronic snoring and speech hyponasality was negligible, but a swollen wet mucosa giving rise to an inadequate airway was recorded less frequently at the post-treatment assessment than at the initial visit. Although improvement in nasal symptoms and signs was recorded more often in the children treated with Dimotapp and/or Ephedrine nose drops, than in the children 761
J. G. Fraser, Meher Mehta and Patricia M. Fraser from whom both these treatments were withheld, the differences were not statistically significant (P>0-05). Pure-Tone Audiometry and Tympanometry
For every child the change between pre- and post-treatment values was calculated for each ear for pure tone threshold, middle ear pressure and compliance. The effect of each treatment was determined by comparing the mean change in children who had received the treatment with the mean change in those who had not. For each comparison a three-level analysis of variance was carried out, and Table III illustrates the method (Healy, 1972) with respect to the effect of Dimotapp on pure-tone thresold. The variation between patients is subdivided into a treatment effect and the residual difference between patients treated alike. The within-patient residual represents the variation in response between the ears of individuals. The variance ratio of 1-0775, which is obtained by testing the treatment mean square against the between-patient residual mean square, shows that treatment with Dimotapp has no significant effect on pure-tone threshold (P >o-O5). A t-test with degrees of freedom equal to those for patients within treatments gives the precise level of significance (Table IV). The variance ratio of the sources of residual variation, 2-2512, shows that, as might be expected, the variance between patients is significantly greater than the variation within patients (P
T
'°775
2-2512
f a
o
0
imo
% w 2 o o 0 3
*§• (P &
p
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rt-
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6 Mean change
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Significance of difference (t-test)
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Significance of difference (t-test)
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J. G. Fraser, Meher Mehta and Patricia M. Fraser observation was worthwhile. A tendency towards spontaneous remission was clearly demonstrated, and after the trial 24 of the 85 children (28%) were discharged from the clinic after being followed up for a year and having remained free of further trouble. In many clinics these children would have been treated surgically when the diagnosis of secretory otitis media was first made. Such unnecessary hospitalization of children can be avoided by careful observation for a few weeks before committing them to surgery. During this period of observation it would be reasonable to treat those children with definite signs or symptoms of nasal allergy either with an antihistamine such as Dimotapp, or with ephedrine nose drops, even though we have shown no improvement in Eustachian tube function with these treatments. The other 61 children in our trial (72%) did come to surgery, which consisted of myringotomies with insertion of ventilation tubes combined with adenoidectomy or adenotonsillectomy. By looking back at the initial history and clinical findings and comparing the children who recovered with those who needed surgery, good and bad prognostic features were identified. These features should help to decide whether to manage a case conservatively or whether to proceed to surgery. A notable finding was that those children who were found to be 'catarrhal' on first examination, with wet, swollen nasal mucous membrane all came to surgery eventually in spite of some improvement during treatment. Children with otalgia fared better than those without. Indeed, not one child who presented with deafness without otalgia recovered on conservative measures. All of the cured group had had otalgia, whereas only 75% of the failed group had earache. This may be a reflection of the fact that it is changes in Eustachian function and middle ear pressure that produce the pain, or perhaps that those children without pain present later. These were the only two factors which we found to have prognostic significance. However, it may be of interest to mention some of the other features examined which might have been expected to affect the outcome, but which failed to do so. Those children with symptoms of nasal obstruction did no worse than those without. Neither the length of history of deafness, nor its intermittent or continuous nature, was related to recovery. Observation of the colour of the drum was of no value. Pure-tone audiometric threshold was no guide to prognosis. Perhaps most disappointing was the fact that tympanometry did not help in selecting a group with a good chance of remission. It is to be hoped that an effective medical treatment for this common condition will be found. Since the medical treatments we used were found to be ineffective, it would be ethical in any future therapeutic trial to compare a group of children having therapy with a group having none. 764
The medical treatment of secretory otitis media Acknowledgements We wish to thank our audiometricians, Miss M. Slemeck and Miss S. MacDonald, for the care given to so much extra work, and Miss C. Jarvis for her generous secretarial help. The work was supported by a grant from the Rockefeller Research Committee of University College Hospital Medical School, and by A. H. Robins Ltd. REFERENCES BROOKS, D. N. (1969) The use of the electro-acoustic impedance bridge in the assessment of middle ear function. Journal of International Audiology, 8, 563. DOLL, R. (1964) Medical treatment of gastric ulcer. Scottish Medical Journal, 9, 183. DRAPER, W. L. (1967) Secretory otitis media in children: A study of 540 children. Laryngoscope, 77, 636. FABRICANT, H. D. (1941) Significance of the pH of nasal secretions in situ. Archives of Otolaryngology, Chicago, 34, 302. HEALY, M. J. R. (1972) Animal Litters as Experimental Units. Journal of the Royal Statistical Society Series C {Applied Statistics), 21, 155. HUNT-WILLIAMS, R. (1968) A method for maintaining middle ear ventilation in children. Journal of Laryngology and Otology, 82, 921. MILLER, G. F. (1970) Influence of an oral decongestant on Eustachian tube function in children. Journal of Allergy, 45, 187. SHEA, J. J. (1971) Autoinflation treatment of serous otitis media in children. Journal of Laryngology and Otology, 85, 1254. THOMAS, J. WARRICK (1958) Para-Bromdylamine Maleate (Dimetane). A clinical evaluation: Report of 140 cases. Annals of Allergy, 16, 128. The Royal Ear Hospital, Huntley Street, London WCiE 6AU.
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