Interventional procedure consultation document

Micropressure therapy for refractory Ménière's disease

Air pressure therapy for difficult-to-treat Ménière's disease

Ménière's disease is a progressive disorder of the inner ear that can affect hearing and balance. Symptoms vary in severity and usually start in one ear but can affect the other in time. The cause is not known but it is thought to result from a rise in pressure in the fluid that bathes the nerve endings in the inner ear. Medications aim to address symptoms (usually the imbalance and/or dizziness) but if they fail, surgery may be used to lower pressure in the inner ear. Micropressure therapy involves inserting a tube through the eardrum into the middle ear and blowing air at low-pressure into the inner ear. This aims to reduce pressure in the ear, relieving symptoms and avoiding the need for more invasive surgery.

The National Institute for Health and Clinical Excellence (NICE) is examining micropressure therapy for refractory Ménière's disease and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about micropressure therapy for refractory Ménière's disease.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the provisional recommendations
• the identification of factual inaccuracies
• additional relevant evidence, with bibliographic references where possible.

Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that NICE will follow after the consultation period ends is as follows.

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.

For further details, see the Interventional Procedures Programme manual, which is available from the NICE website (www.nice.org.uk/ipprogrammemanual).

Through its guidance NICE is committed to promoting race and disability equality, equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our interventional procedures guidance. In particular, we aim to encourage people and organisations from groups who might not normally comment on our guidance to do so.

In order to help us promote equality through our guidance, we should be grateful if you would consider the following question:

Are there any issues that require special attention in light of NICE’s duties to have due regard to the need to eliminate unlawful discrimination and promote equality and foster good relations between people with a characteristic protected by the equalities legislation and others?

Please note that NICE reserves the right to summarise and edit comments received during consultations or not to publish them at all where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.

Closing date for comments: 19 August

Target date for publication of guidance: November 2011

1   Provisional recommendations

1.1   Current evidence on the safety of micropressure therapy for refractory Ménière's disease is inadequate in quantity. There is some evidence of efficacy, but it is based on limited numbers of patients. Therefore this procedure should only be used with special arrangements for clinical governance, consent and audit or research.

1.2   Clinicians wishing to undertake micropressure therapy for refractory Ménière's disease should take the following actions.

• Inform the clinical governance leads in their Trusts.
• Ensure that patients understand the uncertainty about the procedure’s  efficacy and provide them with clear written information. In addition, the use of NICE’s information for patients (‘Understanding NICE guidance’) is recommended (available from www.nice.org.uk/IPGXXXpublicinfo). [[details to be completed at publication]]
• Audit and review clinical outcomes of all patients having micropressure therapy for refractory Ménière’s disease (see section 3.1).

1.3   NICE encourages further research into micropressure therapy for refractory Ménière's disease. Research studies should report long-term outcomes, in particular the need for subsequent surgical management.

2   The procedure

2.1   Indications and current treatments

2.1.1   Ménière’s disease is characterised by symptoms of tinnitus, vertigo and deafness. Diagnosis of the disease is based on the American Academy of Otolaryngology–Head and Neck Surgery (AAO–HNS) Foundation’s guidelines: symptoms that do not respond to 6 months of conventional medical treatment and/or a low-salt diet. It is thought to be caused by raised endolymph pressure in the inner ear (endolymphatic hydrops).

2.1.2   Surgery may be indicated for patients who are refractory to medical management and/or a low-salt diet. Surgical management may include labyrinthectomy, endolymphatic sac decompression and vestibular neurectomy.

2.2   Outline of the procedure

2.2.1   Micropressure therapy for refractory Ménière’s disease is intended to reduce endolymph pressure in the inner ear by administering low-pressure air pulses through the tympanic membrane onto the round window membrane, with the aim of stimulating the flow of endolymphatic fluid.

2.2.2   With the patient under local or general anaesthesia, a grommet or ventilation tube is inserted into the tympanic membrane of the affected ear. A few weeks later, after checking for patency of the grommet by the Valsalva manoeuvre, a hand-held air pressure generator connected to the grommet forms an airtight seal in the outer ear. The device administers computer-controlled micropressure pulses across the tympanic membrane. Three pulse sessions of 60 seconds duration are administered per treatment, with periods of rest (usually less than 1 minute) between each pulse.

2.2.3   Micropressure therapy is administered by the patient at home, usually 3 times per day. Treatment is normally continued for 4–6 weeks, but it can be used for longer.

Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview, available at www.nice.org.uk/guidance/IP/927/overview.

2.3   Efficacy

2.3.1   A randomised controlled trial (RCT) of 40 patients (20 treated by micropressure therapy and 20 treated by a sham procedure) reported a mean number of vertigo attacks of 1.9 and 4 respectively during the last weeks of treatment (p = 0.09). The same study reported a significantly improved functional level (measured using AAO–HNS criteria) in the micropressure therapy group compared with the sham group (2.4 vs 3.5, p = 0.0014) during the last 4 weeks of treatment.

2.3.2   A case series of 36 patients reported a positive response (defined as a shift from Class D to Class A (AAO–HNS Foundation criteria) after treatment in 69% (25/36) of patients. The 11 patients who did not have a positive response went on to have vestibular neurectomy and were disease-free at 2-year follow-up.

2.3.3   A study of 22 patients reported a significant reduction in the mean number of vertigo attacks: from 9.22 to 1.28 (p = 0.001) when the patients only had the grommet (n = 20), and from 9.22 to 1.67 (p < 0.001) when micropressure therapy was started after 20 days (n = 18). There was no significant difference between the two readings at 40 days.

2.3.4   In the case series of 37 patients, 79% (27/34) reported that the treatment had been helpful and had substantially improved their ability to perform daily tasks and work at 2-year follow-up.

2.3.5   The Specialist Advisers listed key efficacy outcomes as reduced frequency and severity of vertigo, increased hearing threshold, reduced tinnitus and reduced need for further therapy.

2.4   Safety

2.4.1   The case series of 37 patients reported middle ear infection in 5 patients. Micropressure treatment was resumed after local antibiotics and an exchange of ventilation tubes.

2.4.2   The case series of 36 patients reported immediate postoperative ear discharge in 6% (2/36) of patients.

2.4.3   The Specialist Advisers listed adverse events reported in the literature or anecdotally as post tympanostomy otorrhoea, repeated need for short-stay ventilation tube insertion and permanent ear drum perforation if a long-stay ventilation tube is used. They considered theoretical adverse events to include infection of the grommet, loss of the ventilation tube in the inner ear, scarring of the ear drum and hearing loss.

2.5   Other comments

2.5.1   The Committee noted that vertigo causes significant disability for some patients and that there is a lack of predictably efficacious conservative treatments for chronic vertigo in Ménière’s disease.  Therefore, if micropressure therapy were shown to be efficacious it could offer a useful option to improve quality of life in selected patients.

2.5.2   The Committee recognised the fluctuating course of Ménière’s disease, which complicates interpretation of evidence on its treatment.

3   Further information

3.1   This guidance requires that clinicians undertaking the procedure make special arrangements for audit. NICE has identified relevant audit criteria and is developing an audit tool (which is for use at local discretion), which will be available when the guidance is published.

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

July 2011

_{Personal data will not be posted on the NICE website. In accordance with the Data Protection Act names will be anonymised, other than in circumstances where explicit permission has been given.}

_{It is the responsibility of consultees to accurately cite academic work in order that they can be validated.}