Advice

The technology

The technology

MolecuLight i:X (MolecuLight Inc) is a handheld imaging device to detect fluorescent bacteria in wounds. It has a touch-sensitive, colour LCD screen and a rechargeable battery. It can capture real-time images and videos in both standard imaging mode and fluorescence imaging mode. A switch on the device allows the user to change between the modes. The best distance for imaging is 8 cm to 12 cm from the wound. The fluorescent images are visualised at the point of care and are designed to identify fluorescent bacteria. If treated, this may help wound closure. MolecuLight i:X detects fluorescent bacteria at levels of 104 colony-forming units/g or higher on a quantitative scale, or predominantly moderate-to-heavy growth on a semi-quantitative scale. It can also measure wound length, width and area. WoundStickers are placed on opposite sides of the wound to detect the wound border.

MolecuLight i:X emits a precise wavelength of violet light. This interacts with the wound tissue and bacteria. It causes the wound and surrounding skin to emit a green fluorescence (because of collagen), and potentially harmful bacteria to emit a red or cyan fluorescence (because of the production of porphyrins or pyoverdine by bacteria). These fluorescence signals are captured by MolecuLight i:X and displayed on a screen. All images and videos can be browsed in the image library.

Accessories for MolecuLight i:X include:

  • WoundStickers (2 WoundStickers are placed next to the wound to measure wound surface area. This can be used in standard imaging mode).

  • DarkDrape including a built-in adapter (for optimal imaging when room lights cannot be turned off. The adapter device connects DarkDrape to MolecuLight i:X).

  • Optical lens wipes are used to clean the display screen and optical components. There are 5 lens wipes included with the device.

Overall, MolecuLight i:X is to help wound assessment, by focusing cleaning, debriding and swabbing of the wound where bacteria are located. It is also intended to improve antibiotic stewardship and optimise the timing of treatment for wound infection.

Innovations

The company claims that MolecuLight i:X can quickly, safely and easily visualise fluorescent bacteria and measure wound surface area at the point of care. The company claims no other devices can visualise bacteria in this way through a handheld device. MolecuLight i:X may lead to better informed clinician decisions, improved antimicrobial stewardship and patient engagement.

Current care pathway

The standard of care involves sampling for culture and using systemic or oral antibiotics in line with local protocol, alongside antimicrobial barrier dressings. When prescribing an antimicrobial, microbiological samples should be taken before prescribing and choice of antimicrobial reviewed after antimicrobial results. For non-severe infections, it may be appropriate to withhold antimicrobials until microbiological sample results are back.

If a diabetic foot infection is suspected and there is a wound, a soft tissue or bone sample from the base of the debrided wound should be sent for microbiological examination. If this cannot be done, a deep swab should be taken because it could give useful information about the choice of antibiotic.

The company states that MolecuLight i:X can be used at any point of the wound management pathway, giving real-time information at the point of care. The technology can also be a supporting tool for diagnosing wound infection in addition to clinical signs and symptoms.

The following guidelines have been identified as relevant to this care pathway:

Population, setting and intended user

The company states that MolecuLight i:X is for people with any acute or chronic wound. Specialities in which the device may be used include tissue viability, podiatry, plastic surgery, burns and in acute and community wound clinics.

MolecuLight i:X could be used in acute settings in secondary care, and also in the community. MolecuLight i:X is for trained healthcare professionals, including tissue viability nurses, GPs, podiatrists, and surgeons (for example, vascular and general surgeons).

Training is needed to use MolecuLight i:X and is included in the cost of the device.

Costs

Technology costs

MolecuLight i:X costs £7,500 (excluding VAT). The expected life cycle of the product is 2 years. The company lists several options to reduce the price, including:

  • volume discounts

  • product bundling including device and consumables

  • a leasing model.

MolecuLight i:X comes with a standard 1-year warranty. An extended warranty can be purchased from the company. MolecuLight i:X comes with WoundStickers to measure 1,000 wounds. Additional WoundStickers are available separately. MolecuLight DarkDrape is a single-use disposable device. This is an optional extra and is available separately.

Costs of standard care

The company cites sources Nussbaum et al. (2017) and Stockl et al. (2004) for estimates of costs of treating infected wounds. These range from $4,345 (USD) to $6,717 (USD), equivalent to around £3,317 to £5,127. In the NHS, the cost for each healed wound ranged from £698 to £3,998 per person and that of an unhealed wound ranged from £1,719 to £5,976 per person (Guest et al. 2016).

Resource consequences

The company states that MolecuLight i:X was introduced to the UK in March 2018, with 100 devices used across the NHS and private healthcare.

MolecuLight i:X costs more overall, but could lead to downstream cost-savings if there are benefits such as reduced closure time for chronic wounds.

Using the MolecuLight i:X imaging device does not need significant changes to facilities. The device is portable. The DarkDrape accessory can be easily attached to the device in clinical settings in which room lights cannot be easily switched off.