Key messages
Balloon dilatation of the Eustachian tube (BET) probably improves Eustachian tube dysfunction compared to nasal medications up to three months after the procedure.
How certain we are about this evidence depends on the length of follow-up and the type of treatment this is compared with.
What is Eustachian tube dysfunction?
The Eustachian tube is a tube which connects the middle ear (part of the ear behind the ear drum) with the back of the nose. People can experience pressure-related symptoms in their ears when this tube does not work well by opening properly. It affects approximately 1% of the UK population.
What did we want to find out?
One treatment option is to insert a balloon into this tube through the nose and inflate it to a high pressure to dilate it, and then remove the balloon. This aims to improve how well the tube opens. We wanted to find out whether BET was better compared with other standard treatments for Eustachian tube dysfunction (usually nasal medications but also other surgical interventions). We were interested in outcomes reported by patients, objective or semi-objective measures of Eustachian tube function, and serious complications. We also looked at several other outcomes, including hearing, ear drum abnormalities, quality of life, the need for another operation, and other less serious complications.
What did we do?
We searched for randomised controlled trials (clinical studies where the treatment people receive is chosen at random). This type of study design provides the most reliable evidence about the effects of a treatment. We searched for studies that compared BET with any other treatment (including no treatment, non-surgical treatment, and other types of surgical treatment). We compared and summarised their results, and rated our confidence in the evidence.
What did we find?
We found nine studies which compared balloon dilatation with other treatments. The most common alternative treatment was nasal medication. A total of 684 people have been included in this review from six different countries across Asia, Europe, and North America. Six of the studies were conducted in multiple hospitals.
Five studies (422 people) compared balloon dilatation with nasal medication. One study (17 people) compared balloon dilatation with no treatment (where patients still had anaesthetic, but they did not receive balloon dilatation). Four studies (275 people) compared balloon dilatation with other surgery.
Up to three months after surgery, it was found that balloon dilatation may reduce Eustachian tube symptoms and objective or semi-objective measures when compared to nasal medications. For most other comparisons, follow-up periods, and outcomes, the evidence was too uncertain to show any clear differences between treatments.
There were no serious complications reported.
What are the limitations of the evidence?
We are not confident in the results because there were concerns about the way the studies were conducted, how the disease outcomes were measured, and the accuracy of the results. Since the studies were done in highly controlled environments, the safety findings might not apply to real-world medical practice.
How up to date is this evidence?
The evidence is current to 18th January 2024.
BET may lead to a clinically meaningful improvement in ETD symptoms compared to non-surgical or no treatment (in the form of sham surgery) at up to three months. The effects of BET on ETD compared to non-surgical treatment are very uncertain beyond three months. However, the certainty of evidence ranged from low to very low, with the studies being underpowered to detect adverse events. The findings of this review should help to inform further BET research and guidelines. Future research should focus on longer-term outcomes and the incidence of adverse events or complications in real-world practice settings.
Eustachian tube dysfunction (ETD) causes symptoms and signs of pressure dysregulation in the middle ear, and is associated with tympanic membrane retraction, otitis media with effusion, and chronic otitis media. Interventions aiming to improve symptoms can be non-surgical or surgical, including balloon dilatation of the Eustachian tube, also known as balloon eustachian tuboplasty (BET) for obstructive ETD. However, existing published evidence for the effectiveness and safety of BET remains unclear.
To evaluate the effects of balloon dilatation of the Eustachian tube in adults with obstructive Eustachian tube dysfunction.
The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid M>DLINE; Ovid Embase; Web of Science; Clinicaltrials.gov; ICTRP and additional sources for published and unpublished trials. The final search was updated on 18th January 2024. There were no restrictions on language, publication date or study setting.
Randomised controlled trials were included if they allocated adult participants with chronic obstructive ETD to treatment randomly and compared BET with non-surgical treatment, no treatment, or other surgical treatment. Studies with other designs were excluded.
At least two review authors independently selected trials using predetermined inclusion criteria, assessed the risk of bias, extracted data, and rated the certainty of evidence (CoE) according to GRADEpro. Statistical analyses were performed using a random-effects model and interpreted according to the most recent version of the Cochrane Handbook. Predefined primary outcomes were obstructive ETD symptoms, Eustachian tube function (objective or semi-objective tests), or serious adverse events. Secondary outcomes were hearing, tympanic membrane abnormalities, quality of life, and other adverse events.
Nine trials were identified with 684 randomised participants across three comparisons: BET versus non-surgical treatment (five trials, 422 participants), BET versus no treatment (sham surgery; one trial, 17 participants), and BET versus other surgery (four trials, 275 participants). None of the studies were rated with an overall low risk of bias.
Comparing BET to non-surgical treatment up to three months, there is low-certainty evidence showing that BET may reduce patient-reported ETD symptoms (change in ETDQ-7: mean difference (MD) -1.66 (95% CI -2.16 to -1.16; I2 = 63%; 4 RCTs, 362 participants)). There is very low-certainty evidence that BET may improve ETD as assessed by objective or semi-objective measures (improvement in tympanometry: RR 2.51 (95% CI 1.82 to 3.48; I2 = 0%; 3 RCTs, 369 participants). Between three and 12 months, the evidence is very uncertain whether BET reduces ETDQ-7: MD -0.55 (-1.31 to 0.21; 1 RCT, 24 participants). The evidence is very uncertain whether BET improves ETD as assessed by objective or semi-objective measures (improvement in tympanometry: RR 2.54 (95% CI 0.91 to 7.12)). Evidence was downgraded for risk of bias, imprecision, indirectness, or a combination of these.
Comparing BET to no treatment (sham surgery trial) up to three months, there is very low-certainty evidence that BET improves ETD as assessed by patient-reported ETD symptoms (change in ETDQ-7: MD -0.54 (95% CI -2.55 to 1.47; 1 RCT, 17 participants)). Between three and 12 months, the evidence is very uncertain whether BET improves ETD as assessed by ETDQ-7 (MD 0.16 (95% CI -0.75 to 1.07; 1 RCT, 17 participants)). Evidence was downgraded for indirectness and twice for imprecision.
Although there were no serious adverse events reported, these studies were underpowered to detect adverse events and were performed by highly trained and experienced investigators under strict study protocols. This could underestimate the true risk of adverse events by less experienced clinicians in everyday clinical practice. Evidence was rated as very low certainty, downgraded for risk of bias, imprecision, and indirectness.