Interventional procedure consultation document

Epiretinal brachytherapy for wet age-related macular degeneration

Treating abnormal blood vessel growth in wet age-related macular degeneration using localised radiotherapy

Age-related macular degeneration (AMD) is an eye disorder affecting the macula, which is the area at the centre of the retina (the back of the eye) responsible for central vision (seeing things straight in front of you). Wet AMD happens because fluid leaks out of abnormally formed arteries and veins into the area under the macula (the choroid layer), causing distorted vision and scarring. Loss of vision is progressive and often rapid.

Radiotherapy has sometimes been used in conjunction with pharmaceutical injections in people with wet AMD to treat the abnormal blood vessels growing under the macula. A probe is carefully inserted into the eye through a small incision and radiation therapy is used to destroy the vessels. The aim of this procedure is to slow down the growth of the blood vessels or stabilise the patient’s vision, and to reduce the number of pharmaceutical injections required.

The National Institute for Health and Clinical Excellence (NICE) is examining epiretinal brachytherapy for wet age-related macular degeneration 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 epiretinal brachytherapy for wet age-related macular degeneration.

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: 26 July

Target date for publication of guidance: October 2011

1   Provisional recommendations

1.1   Current evidence on the efficacy of epiretinal brachytherapy for wet age-related macular degeneration (AMD) is inadequate and limited to small numbers of patients. With regard to safety, vitrectomy has well recognised complications and in addition there is a possibility of subsequent radiation retinopathy. Therefore this procedure should only be used in the context of research.  Research studies should address whether epiretinal brachytherapy reduces the progression of wet age-related macular degeneration and whether it can result in the reduction of the number of injections of antivascular endothelial growth factor agents (anti-VEGF) required. Long-term outcomes should be reported.

2    The procedure

2.1   Indications and current treatments

2.1.1   Age-related macular degeneration is the most common cause of blindness in developed countries. A proportion of patients with AMD have wet AMD. Wet AMD is characterised by the abnormal growth of blood vessels in the choroid layer underneath the macular part of the retina. These vessels can threaten vision if they leak and cause scarring.

2.1.2   Current treatments for wet AMD include laser photocoagulation, photodynamic therapy (PDT), intravitreal injections of antivascular endothelial growth factor agents and implantation of miniature lens systems. Patients with advanced disease may benefit from optical aids such as magnifying glasses.

2.2   Outline of the procedure

2.2.1   Epiretinal brachytherapy for wet AMD aims to slow down the growth of blood vessels that cause wet AMD by administering beta radiation therapy targeted at the abnormal, leaking vessels.

2.2.2   The procedure is usually carried out with the patient under local anaesthesia, and is normally used in combination with an anti-VEGF agent. A vitrectomy is performed, and an intraocular epiretinal probe is placed in the vitreous cavity, over the fovea. Beta radiation is delivered by the probe. The radiation dose received by the patient is less than the dose received during a typical chest X-ray. The sclera is closed with an absorbable suture and the eye is patched. Prophylactic antibiotics and steroids are usually administered.

2.2.3    A number of different devices are available for this procedure.

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/648/overview

2.3   Efficacy

2.3.1   A case series of 34 patients treated by epiretinal brachytherapy (concomitant treatment not described), reported that 63% and 50% of patients receiving 24 Gy and 15 Gy of radiation respectively gained 1 or more letters of visual acuity at 12-month follow-up (absolute figures not given). In the same study, visual acuity improved by more than 15 letters in 21% and 0% of patients respectively (absolute figures not given).

2.3.2   A different case series of 34 patients treated by epiretinal brachytherapy plus anti-VEGF injections reported a gain of 8.9 letters in best-corrected visual acuity after the procedure; 38% (13/34) of patients demonstrated a clinically significant improvement of 3 lines or more at a median follow-up of 12 months.

2.3.3    The Specialist Advisers listed key efficacy outcomes as retention of visual acuity, number of anti-VEGF injections required, and time to recurrence of AMD.

2.4   Safety

2.4.1   Both the case series of 34 patients reported no adverse events caused by radiation at 12-month follow-up.

2.4.2   Retinal tear was reported in 6% (2/34) and 3% (1/34) of patients in the 2 case series.

2.4.3   The case series of 34 patients treated by epiretinal brachytherapy plus anti-VEGF injections reported raised intraocular pressure in 6% (2/34) of patients (follow-up not stated).

2.4.4   The Specialist Advisers listed anecdotal or reported adverse events as cataract formation, retinal haemorrhage, retinal detachment, infective endopthalmitis, and radiation retinopathy. They considered theoretical adverse events to include radiation optic neuropathy and radiation-induced malignancy.

2.5   Other comments

2.5.1   The Committee noted that a number of controlled clinical trials are currently in progress.

3   Further information

3.1    For related NICE guidance see www.nice.org.uk

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

June 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.}