Guidance

Diabetic eye screening: guidance on camera approval

Updated 14 March 2024

About the cameras

The only acceptable method of systematic screening for diabetic eye disease in the NHS currently is 2-field digital retinal photography.

The NHS diabetic eye screening (DES) programme has a purchasing framework for digital fundus cameras with NHS Supply Chain.

This allows NHS organisations to buy approved cameras from a catalogue at pre-negotiated prices.

Programmes that plan to buy cameras for screening should consult NHS Supply Chain first.

The benefits of using the framework contract include:

• an expert team tests all fundus cameras to make sure they can detect subtle diabetic pathology, are robust and easy to use

• provision of a replacement camera at short notice in the event of failure as part of clear maintenance agreements

• certification that all cameras will connect to approved DES management software

Camera approval process

Suppliers must submit new cameras for evaluation at one of the DES programme’s formal assessment days. The DES programme holds assessment days every 12 months.

The DES programme will arrange a meeting with the agreed clinical working group and NHS Supply Chain at least 12 weeks before the pre-arranged annual assessment day.

The working group, programme specialists and NHS Supply Chain will review and confirm the current specification. Once agreed, NHS Supply Chain will issue the latest version to the camera suppliers on the NHS Supply Chain Framework. Suppliers will be asked if they have any new cameras they would like to be considered for the DES approved list.

Where a significant change has been made to the specification, all cameras already on the approved list will need to be reassessed to make sure they continue to meet the criteria.

Suppliers should use the specification as a check list in the first instance, and confirm to supply chain that their camera meets the criteria before it is accepted for the assessment day.

Suppliers respond formally to the specification with full details of how their cameras meet the specification along with appropriate documentation – a brochure or user manual providing full detail. Any queries from suppliers are sent to NHS Supply Chain where they are collated and passed to the working group. Responses are passed back via NHS Supply Chain.

Where there is agreement that there is enough demand for the assessment day to be delivered, arrangements are made for venue, IT resource, clinical resources, IT system (laptop), assessment volunteers and supplier invitations.

Supplier written responses are assessed by the working group and a list of suppliers meeting the essential criteria is passed to NHS Supply Chain which sends assessment day invitations to the successful suppliers.

Suppliers submit new cameras for evaluation at the DES formal assessment day and the cameras are fully evaluated by IT and clinical experts on factors including image quality, IT connectivity and other criteria defined in the specification. Connectivity will be tested using a laptop with appropriate software installed.

The working group meets to discuss the outcomes from the assessment day, agrees which cameras are suitable and passes this on to NHS Supply Chain, which then informs the suppliers and adds the new units to the list of devices that local providers can buy under the framework agreement.

Approved models

The national DES programme recommends that all local DES providers should select cameras from the framework agreement. This makes sure they get the most suitable equipment and correct maintenance contract.

Some models may not be available because suppliers can retire models without notice.

Anyone working in the NHS can get more information, including prices for single and multiple units, by emailing Ophthalmology@supplychain.nhs.uk.

Contact the PHE Screening helpdesk with any other questions relating to digital fundus cameras. The helpdesk is not for media enquiries and does not have access to screening results.

Local DES services should trial cameras before buying to ensure they are compatible with local systems. Clinical leads should oversee this process.

Approved fundus cameras available to buy

Supplier	Model
Birmingham Optical Group	AFC-330 Fundus Camera
Birmingham Optical Group	Nidek Scan Duo 2
Birmingham Optical Group	Nidek RS-330
Sense Medical	Canon CR-2AF
Sense Medical	CR-2 Plus AF
Haag-Streit	iCam
Sense Medical	Kowa VX-20
Sense Medical	nonmyd 8 and 8s
Sense Medical	nonmyd WX-3D
Topcon	NW400
Topcon	DRI OCT Triton (and Plus)
Sense Medical	Kowa nonmyd AF
Sense Medical	Kowa WX-3D
Sense Medical	Canon CR-10
Sense Medical	Canon Xephilio OCT R1
Topcon	OCT-1 Maestro 2
BIB Ophthalmic Instruments	Optopol Revo FC
Topcon	NW500
Topcon	TRC NW8

Approved cameras no longer available to buy as a new unit

Supplier	Model
Canon (Carleton)	CR1
Canon (Carleton)	CR1-MK2
Canon (Carleton)	CR-DGi
Canon (Carleton)	CR-6
Carleton	Canon CR-2
Carleton	CR-2 Plus
Nidek (Birmingham Optical Group)	AFC-210
Carl Zeiss	Visucam 200
Carl Zeiss	Visucam 224
Carl Zeiss	Visucam 500
Carl Zeiss	Visucam 524
Carl Zeiss	Cirrus 600
Carl Zeiss	Cirrus 800
Haag-Streit	DRS
KOWA (Sense Medical)	nonmyd 7
Topcon	TRC NW6
Topcon	3D OCT 50K
Topcon	3D OCT FA+
Topcon	3D OCT-1 Maestro
Topcon	TRC NW8 (F, AF+)

Camera maintenance

The approved national specification for cameras can change. This can have a cost implication for local programmes.

Providers and commissioners should make sure the capital depreciation allowance is realistic.

Older cameras no longer considered suitable for screening

Providers can sometimes continue to use cameras that become obsolete after a specification change. This is allowed if the:

• provider bought the cameras from new
• cameras were on the approved list when bought
• clinical lead is happy with the image quality produced

If the local DES service decides the specification change is urgent and essential then they may have to replace the cameras.

If a DES service wants to continue to use approved cameras that are no longer available to buy then the clinical lead must make sure image quality remains acceptable.

Local providers should also service and clean cameras as required to maintain image quality. Cameras that provide inadequate quality images can introduce risk to a programme.

Monitor specification (under review)

The limiting resolution is vertical on conventional aspect ratio desk top monitors. 1200 pixels vertical resolution is the preferred minimum. It provides a large visible area of the fundus at the magnifications generally used for grading.

This means resolutions of 1600 x 1200 or 1920 x 1200 with the increasing move to widescreen format.

Many suppliers have moved to using 1920 x 1080 as a standard widescreen resolution. 1200 vertical is still available but sources are more restricted.

Higher resolution screens will reduce the amount of scrolling necessary at any given magnification of image. Extra costs are minimal when offset against the time spent examining the image. Higher contrast ratios are likely to be beneficial.

The minimum acceptable standard is a vertical resolution of 1080 (1920 x 1080). The achievable and recommended standard is a minimum of 1200 (1920 x 1200 or higher). Larger screens are generally more comfortable to use than smaller ones. Local DES services should consider larger screens in areas where graders are working for extended periods of time. Services should optimise the positioning, ambient lighting and reflectivity of screens.

The national DES programme does not recommend the use of laptop screens for grading due to a lack of evidence on quality. Grading using a laptop should only be undertaken with a risk assessment. The clinical lead should confirm that the laptop screen quality is equivalent to a desktop grading monitor. The DES programme recommends a side by side comparison. The ergonomics and environment should be appropriate for grading. Laptop grading may also be undertaken when connected to a suitable monitor.