The technology

Noctura 400 Sleep Mask (Polyphotonix Medical) is for people with DR and DMO. The mask should be worn over the eyes during sleep for as long as the person is in darkened conditions, up to a maximum of 8 hours each night. It contains 2 organic light-emitting diodes (OLEDs) in thick glass behind acrylic lenses. The OLEDs emit a dose of light at a particular wavelength into the wearer's eyes.

The main purpose of the mask is to stop or slow the production of vascular endothelial growth factor (VEGF). VEGF causes new blood vessels in the eye to grow; these are weak and leak fluid (oedema) into the macula. The macula is the area of the retina responsible for the clearest vision. Fluid leaking into the eye can cause scarring and cell loss and if left untreated may lead to significant loss in vision or permanent blindness. The Noctura wavelength is selected to target rod photoreceptors in the retina; this may prevent rod cells from adapting to the dark. This is designed to reduce the need for the additional oxygen, which would otherwise be needed by the dark-adapted eye. It also reduces the risk of nocturnal retinal hypoxia in the diabetic eye.

The moulded acrylic window in a Noctura 400 Sleep Mask keeps the OLEDs away from the eyelids. The OLEDs are powered by 2 coin-cell batteries attached to printed circuit boards, housed in a padded fabric mask held in place over the eyes with a fabric strap and fastener. The mask records data on use and compliance for 8 hours each night over a 12-week period. The data recorded are retrieved by placing the mask in a reader device containing PPX Works software. The reader is programmed to each person's normal sleep pattern and has a 14-hour operational window. Noctura 400 Sleep Mask is partially recyclable, and is replaced after each 12-week period. The data stored on the reader are then analysed. As the sleep mask is designed to prevent DR, people using it would generally continue to have this treatment indefinitely.


Noctura 400 Sleep Mask is a non-pharmacological, non-invasive treatment that delivers light to the back of both eyes while the person is sleeping. If used in the early stages of DR it may slow down or even stop the condition from worsening. At present, when early-stage DR is detected there are no treatment options available other than monitoring until the disease reaches a sight-threatening stage.

Current NHS pathway or current care pathway

People with diabetes should have an eye screening test at least once every year as part of the English national screening programme for DR (see NICE's guideline on diagnosing and managing type 1 diabetes and type 2 diabetes in adults, as well as the Royal College of Ophthalmologists' guidelines on DR). The frequency of screening depends on the presence and severity of DR or DMO. At the first screening appointment, photographs are taken of the retina, and are graded. If there is no retinopathy, or very early changes, then the person is recalled for another photograph in 1 year. If pre-proliferative changes or non-sight-threatening maculopathy are detected, the person may be referred to hospital or clinic for more frequent review. If the condition progresses to a more advanced or proliferative stage, treatment is offered every 2 to 4 weeks.

Treatment consists of laser photocoagulation of the leaky blood vessels for DR and intravitreal injections of anti-VEGF (see NICE's technology appraisal guidance on ranibizumab and pegaptanib for age-related macular degeneration) or steroids (see NICE's technology appraisal guidance on dexamethasone intravitreal implant) for DMO. If DMO does not respond to non-corticosteroid treatment, intravitral implants of dexamethasone are an option for eyes with an intraocular lens.

Population, setting and intended user

Noctura 400 Sleep Mask is designed for use at home by people with diabetes at any stage. If adopted by the NHS, the Noctura 400 Sleep Mask could be used as part of a preventative strategy in primary care in people with no evidence of retinopathy or, more likely, for people with late-stage DR and DMO. For people with late-stage DR or DMO, clinical ophthalmologists would prescribe Noctura 400 Sleep Mask in a secondary care, outpatient setting.


Technology costs

Table 1 Costs associated with Noctura 400 Sleep Mask



Additional information

Noctura 400 Sleep Mask

Unprogrammed masks:

£172 for 12 weeks (4 to 5 per year).

Total annual cost, £688 to £860 per person.

Preprogrammed masks:

£197 for 12 weeks (4 to 5 per year).

Total annual cost, £788 to £985 per person.

People will need up to 5 masks per year.

Unprogrammed masks are supplied in batches of 20.

Computer, PPX Works software licence and 1 day of set-up and training


One-off set-up cost for clinics using unprogrammed masks. Fee includes a lifetime software license; no renewal fees are charged.

Cost of an outpatient appointment (1 per year)

£53 per appointment;

total annual cost £212 to £265 per patient (4 to 5 appointments per year).


All patients need a new mask every 12 weeks and the company recommend a face-to-face review each change, although this is subject to clinical judgement. This equates to a patient getting up to 5 masks and outpatient appointments per year.

There are 2 purchasing options for the mask:

  • Unprogrammed masks are slightly cheaper and need programming by NHS staff before use. They are subject to an additional one-off set-up cost for individual clinics; the cost per patient will be dependent on the size of the clinic. The total annual cost per patient for this approach is £900 to £1,125 (excluding the programming cost; dependent on number of masks needed per year).

  • Preprogrammed masks are set-up by the company and sent directly to patients with no clinic set-up costs. The total annual cost per patient for this option is £1,000 to £1,250.

Costs of standard care

The total cost of intravitreal anti-VEGF injections for DMO in 1 eye is £6,536 per patient per year (based on £550 for cost of treatment; £267 per day-case appointment; and an average of 8 treatments per year). The corresponding total cost of treatment of both eyes is £10,936 (assuming both eyes are treated at the same appointment). The cost of laser photocoagulation is £138 per procedure and people would also need monitoring clinic visits, up to 4 per year for those with proliferative DR at a cost per visit of £84 (Royle 2015). These costs were inflated from 2012/13 to 2016/17 prices using the hospital and community health services index (PSSRU 2017).

Resource consequences

Using Noctura 400 Sleep Mask would represent an additional cost to the NHS. If any treatment were shown to prevent or slow the progression of early-stage DR, then it may reduce interventions, such as intravitreal injections, which would lead to NHS savings. Similarly, if shown to be as effective as current interventions, Noctura Mask 400 could save money. However, there is currently no evidence to support these assumptions. In particular, there is no evidence of the effectiveness of the mask in people with late-stage DR or DMO and no formal cost-effectiveness analysis has been done comparing Noctura 400 Sleep Mask to current standard care.

Adopting Noctura 400 Sleep Mask is not expected to have a significant effect on NHS facilities or infrastructure, aside from the need for one-off training for eye clinicians that the company estimates takes no more than 1 day. Additional staff training would be needed on using Noctura 400 Sleep Mask and, depending on the supply model that the hospitals selects, instruction in programming it. The company estimates that about 2 nurses per hospital would need training, which would last for either 1 to 2 hours or 1 day, depending on the level of training that was needed.