The National Institute for Clinical Excellence is examining radiotherapy for macular degeneration and will publish guidance on its safety and efficacy to the NHS in England and Wales. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisors, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about radiotherapy for macular degeneration.

This document has been prepared for public consultation. It summarises the procedure and sets out the provisional recommendation made by the Advisory Committee.

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

The process that the Institute 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 the Final Interventional Procedure Document (FIPD) and submit it to the Institute.
• The FIPD may be used as the basis for the Institute's guidance on the use of the procedure in the NHS in England and Wales.

For further details, see the Interim Guide to the Interventional Procedures Programme, which is available from the Institute's website (www.nice.org.uk/ip).

Closing date for comments: 23 December 2003

Target date for publication of guidance: March 2004

Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.

Current evidence on the safety and efficacy of radiotherapy for age-related macular degeneration does not appear adequate for this procedure to be used outside of a randomised controlled trial, with special arrangements for consent. Clinicians wishing to undertake radiotherapy for age-related macular degeneration should only do so as part of a randomised controlled trial, and should inform the clinical governance leads in their Trusts. They should ensure that patients offered it understand the uncertainty about the procedure's safety and efficacy and should provide them with clear written information. Use of the Institute's Information for the Public is recommended. Clinicians should ensure that appropriate arrangements are in place for audit and research. Publication of safety and efficacy outcomes will be useful in reducing the current uncertainty. NICE is not undertaking further investigation at present.

Age-related macular degeneration comprises a group of conditions that affect central vision, and can lead to irreversible blindness. The prevalence of macular degeneration increases with age.

Ninety percent of people with age-related macular degeneration (AMD) have dry (atrophic) macular degeneration, characterised by thinning of the macular retina. The other 10% have wet (exudative or neovascular) macular degeneration, characterised by the growth of abnormal new blood vessels in the choroid layer underneath the retina. These new vessels can leak fluid and cause scarring, which can threaten vision. The vessels can be classified using fluoroscein angiography into 'classic' if they can be seen clearly and 'occult' if they cannot. Wet macular degeneration usually occurs in people who already have dry macular degeneration. Of these two conditions, wet macular degeneration progresses more quickly and vision loss is more severe.

Laser therapy is used to coagulate new vessels in wet macular degeneration. However, the procedure itself may permanently impair vision, especially if the vessels are very close to the fovea. Recurrence is common. Standard laser therapy appears to work only in people with classic neovascular macular degeneration.

Other new treatments for macular degeneration include surgery to remove new vessels, macular translocation, photodynamic therapy and new drugs that suppress new vessel formation (antiangiogenic drugs).

This procedure involves the use of radiotherapy to destroy the new vessels formed in patients with wet neovascular AMD. The beam of radiotherapy is angled to avoid damage to the optic nerve and structures in the other eye.

Three randomised controlled trials (RCTs) reported radiotherapy as having no significant benefit on visual acuity when compared with sham treatment or observation. Two RCTs found that radiotherapy reduced loss of visual acuity when compared with very low dose (effectively sham) radiation or observation only. However, the dose of radiation used varied among the studies, ranging from 2 Gy to 20 Gy. For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors considered trials to have shown little or no benefit to using radiotherapy, and that any effect was likely to be modest. One Specialist Advisor also noted that all patients in the UK being treated with this procedure were enrolled in clinical trials.

In the RCTs identified, the main complication reported was cataract which ranged from 1/51 to 28/42 eyes. Other potentially serious complications reported were: vitreous haemorrhage (1/42 eyes) and retinal detachment (1/42 eyes). For more details, refer to the sources of evidence (see Appendix).

One Specialist Advisor considered the main safety concerns of this procedure to be radiation retinopathy, dry eyes and cataract.

Current evidence does not show the procedure to be efficacious.

The efficacy of this procedure may be related to the dose of radiation administered, but there is insufficient evidence to support this hypothesis.

NICE issued guidance on the use of photodynamic therapy for age-related macular degeneration in September 2003 (www.nice.org.uk/pdf/68_PDTGuidance.pdf)

The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making it's provisional recommendations.

• Interventional Procedure Overview of Radiotherapy for macular degneration, December 2002

Available from: www.nice.org.uk/ip081overview