Advice

The technology

The technology

The NaviCam (ANKON) is a miniaturised wireless endoscope in a single-use capsule, which is remotely controlled by magnetic guidance hardware. This includes a magnetic guidance robot, computer workstation and software. The magnetically controlled endoscopy system is indicated for the diagnosis of upper gastrointestinal (GI) tract and small bowel disease.

To use NaviCam, the person having the procedure must fast overnight then drink about 1 litre of water and take simethicone (a defoaming agent). This reduces gastric mucus and distends the stomach, improving visualisation. During the procedure, a portable data recorder is worn outside the body, which is secured to the skin using adhesive pads before the person swallows the NaviCam capsule. The small capsule (12 mm x 28 mm) is made up of a camera, an LED light source, a magnet, a wireless circuit for sending and receiving signals, and a small battery that can last for more than 8 hours.

The person lies on a fixed bed, which is part of the magnetic guidance robot. The robot guides the capsule through the upper GI tract (including the stomach). This can be done in automatic mode, or in manual mode using a joystick guided by the endoscopist. Images are taken at 2 frames per second and sent wirelessly to the portable data recorder. The images are transferred to a computer for a clinician to examine, and can be stored in NHS IT systems (such as primary and acute care systems [PACS]). Once the upper GI tract examination is finished, the person can leave the endoscopy suite, while still wearing the portable data recorder. Magnetic control is not needed to guide the capsule through the small bowel so the recording can continue while the person is at home or on a ward. The location of the capsule can also be identified at any time using a handheld detector. The video recording will continue for about 8 hours. The capsule is then passed in the person's stool and discarded.

The NaviCam is contraindicated in pregnancy and for people with pacemakers, implantable electronic devices or implanted metal parts (similar exemption criteria to MRI scans).

Innovations

The NaviCam is less invasive than conventional gastroscopy, needing no intubation or sedation. Unlike other magnetic or passive wireless capsule endoscopy systems, the NaviCam capsule can be controlled remotely and guided through the upper GI tract using a magnetic guidance robot. This is designed to improve manoeuvrability in the stomach and small bowel, aiming to improve gastric mucosal examination.

Current NHS pathway

Conventional gastroscopy is a routine test for identifying abnormalities in the upper GI tract. The procedure is usually done as an outpatient day case and involves an endoscope being passed through the mouth to examine the oesophagus, stomach and proximal small bowel (duodenum). Conventional gastroscopy can be used for diagnostic or therapeutic purposes; although it does not reach the distal small bowel, it enables tissue sampling and endoscopic treatments of the proximal jejunum.

To examine the entire length of the small bowel, device-assisted enteroscopy techniques (such as balloon or spiral enteroscopy) or wireless capsule endoscopy systems can be used. Device-assisted enteroscopy can be used for diagnosis and also for therapeutic endoscopic procedures and biopsies, which are not possible with wireless capsule endoscopy. Wireless capsule endoscopy systems currently used in the NHS use capsules which are not under magnetic control. The 2013 NHS Atlas of Variation in Diagnostic Services reported a 29-fold variation in wireless capsule endoscopy procedure rates across England.

NICE's guidance on the management of acute upper gastrointestinal bleeding recommends that people with severe acute upper GI tract bleeding who are haemodynamically unstable have an endoscopy within 2 hours. Those who are haemodynamically stable should be given an endoscopy within 24 hours, but there are no recommendations about the type of endoscopy that should be used.

NICE's interventional procedures guidance on wireless capsule endoscopy for investigation of the small bowel states that evidence on safety and efficacy is adequate to support its use; but recommends that other investigations should be used in people with suspected strictures, such as those with Crohn's disease.

The European Society of Gastrointestinal Endoscopy guideline for small bowel capsule endoscopy and device-assisted enteroscopy for the diagnosis and treatment of small bowel disorders states that capsule endoscopy should be used as a first-line investigation in people with overt GI bleeding of unknown origin. In people with suspected Crohn's disease, it should only be used when there are negative ileocolonoscopy findings without obstructive symptoms or known stenosis. In people with suspected coeliac disease, capsule endoscopy is not recommended unless they are unwilling or unable to have conventional endoscopy. For the detection of small bowel tumours, it is only recommended if there is unexplained overt GI bleeding and iron-deficiency anaemia. If imaging tests suggest a tumour may be present, device-assisted enteroscopy is preferred.

NICE is aware of the following CE-marked device that appears to fulfil a similar function as the NaviCam, but this uses a handheld portable magnet to control the capsule, rather than a guidance robot:

Population, setting and intended user

The NaviCam is designed for use in the diagnosis of upper GI tract and small bowel disease, for people presenting with upper GI tract bleeding, suspected malignant disease or other suspected gastric disorders, such as Crohn's disease.

The technology is likely to be used in specialist endoscopy centres by trained clinicians, such as gastroenterologists and nurse endoscopists. Although the initial upper GI tract examination under magnetic control will be done in an endoscopy suite, the remaining 8 hour small bowel examination can be done in the ward or at home.

Costs

Technology costs

The costs of the NaviCam are shown in table 1. The company has estimated the cost of using the NaviCam to be about the same as standard gastroscopy (£418 per patient). This estimate is based on theoretical assumptions that the system is used for 500 patients per year or about 6 to 8 patients each day, and that the technology has a lifespan of 20 years. These assumptions have not been tested, and may be overestimates.

Table 1 NaviCam technology costs (excluding VAT)

Description

Cost

Additional information

NaviCam System

£175,000

Includes magnetic guidance robot, bed, workstation, 1 portable wearable data recorder, 1 capsule position detector, and clinician training

Single-use NaviCam capsule

£400 each

Simethicone for gastric preparation

Less than £0.10 per dose

Maintenance costs

£2,500 per year

Costs of standard care

The NHS tariff for reimbursement for a standard diagnostic endoscopic procedure of the upper GI tract is £416 for adults (aged 19 years and over) and £869 for children and young people (aged between 2 and 18 years). For wireless endoscopy, the tariff is £734 for adults and £1,019 for children (NHS reference costs 2015–16). Specialist commentators estimated the costs of a standard reusable gastroscopy system to be between £30,000 and £100,000. Other wireless endoscopy systems were estimated to cost about £7,000 with single-use capsules costing about £500 each, with a lifespan of 5 years.

Resource consequences

A space measuring 3 m x 4 m is needed to install the NaviCam guidance equipment and 1 trained clinician is needed to use the device. If adopted, there may be a reduced need for staff compared with conventional gastroscopy, because only 1 operator is needed and no sedation or intubation is needed. A specialist commentator stated that in comparison, standard gastroscopy needs 1 expert medical endoscopist and 2 nurse assistants. The company states about 10 days' training is needed to operate the device and interpret images: 2 operators' training is provided with each system.

The NaviCam procedure takes 25 to 40 minutes from the person swallowing the capsule to the test result for the upper GI tract examination. This is made up of 15 to 30 minutes for the procedure and 10 minutes to interpret the images.

The NaviCam is currently being used in 1 UK centre as part of a research study.