Advice
The technology
The technology
HealthVCF (Zebra Medical Vision [Zebra-Med]) is software that uses artificial intelligence (AI) to detect moderate-to-severe vertebral compression fractures from CT scans of the chest or abdomen. The AI solution does not distinguish between acute and chronic fractures, but both would be detected by the software. HealthVCF forms part of a wider Bone Health Solution offered by the company. The company states that the Bone Health Solution, which is in development, will include CT predictors of fracture such as bone mineral density. This briefing is focused on HealthVCF, which is currently the only commercially available component of the Bone Health Solution.
CT scans are sent automatically by picture archiving communication systems (PACS) to the Zebra‑Med imaging analytics engine (server). Once received, the HealthVCF AI‑based algorithm analyses the scans for vertebral compression fractures. Algorithm results are displayed in the Zebra Insight window, the technology's user interface, which automatically appears inside the PACS viewer used to view CT scan images.
According to the company, the software can be configured into 2 distinct modes:
-
Direct to radiologist at point of reporting. In this mode, the radiologist is alerted to suspected positive findings in the scan at the time of reading a case and writing the radiology report. This is done through a pop‑up alert window when the CT image is opened, which provides images of the detected fracture. The radiologist can confirm or refute the findings and enter locally agreed text into the radiology report. A list of radiologist‑approved fractures is auto populated into Zebra Insight, which can then be reviewed and followed up by fracture liaison services (FLS).
-
Direct to FLS. In this mode, eligible scans are analysed by the algorithm and a list of scans with suspected positive findings are sent directly to the FLS team through the Zebra Insights desktop application. The findings can then be reviewed and validated by a specially trained FLS team, with the support of a radiologist.
The company states that on completion of the analysis, the CT images are deleted from the Zebra‑Med server. The algorithm results are stored and are accessible to the radiologist in the Zebra Insight window within the PACS workstation.
The company states that Zebra Medical Vision is compliant with General Data Protection Regulations and has the organisational and technical measures in place to fulfil its fundamental requirements.
Innovations
HealthVCF is designed to detect and alert radiologists of suspected vertebral compression fractures in people who are having chest or abdomen CT scans for other indications. The company claims that using HealthVCF allows radiologists to increase reporting of primary fractures in people with osteoporosis. These people can then be referred for fracture prevention care before they have a more serious fracture, such as a hip fracture.
Current care pathway
Vertebral compression fractures can be caused by trauma, cancer, or osteoporosis. Most vertebral compression fractures are identified incidentally when found on chest and abdominal X-ray or CT images taken for other indications.
Osteoporosis is an asymptomatic condition that weakens bone strength, making them fragile and more likely to break. It develops slowly over several years and is often only diagnosed when a fall or sudden impact causes a bone to fracture. The most common injuries in people with osteoporosis are fractures of the wrist, hip, or vertebrae.
NICE's guideline on osteoporosis: assessing the risk of fragility fracture recommends that women aged over 65 and men over 75 should be assessed for fracture risk. People under 65 should also be considered for assessment of fracture risk if they have risk factors such as a history of falls, a previous fragility fracture, or current use of oral or systemic glucocorticoids. Methods of risk assessment includes using tools such as the FRAX tool or the QFracture risk calculator. If a person's risk is high enough that intervention is considered, then bone mineral density (BMD) is measured using a dual X‑ray absorptiometry scan (DXA) and a person's risk score is recalculated using the FRAX tool with BMD.
Treatment for osteoporosis involves treating and preventing fractures and using medicines to strengthen bones. People that have been diagnosed with osteoporosis are referred to fracture liaison services (FLS). FLS are coordinator-based health programmes designed to prevent secondary fractures in people with osteoporosis. Some FLS also offer screening programmes which involve screening for wrist or vertebral fractures in people that are suspected of having osteoporosis.
Population, setting and intended user
HealthVCF is intended as a tool to opportunistically detect vertebral compression fractures from chest or abdomen CT scans in people aged over 50. It would be used by radiologists in secondary care settings to support their review of chest and abdominal CT scans by providing additional information to support detection and treatment planning. HealthVCF may also be used by radiologists who work at an FLS centre who want to systematically enrol people onto a fracture prevention program.
The UK National Screening Committee states that looking for vertebral compression fractures in chest or abdomen CT scans in people who have not asked for advice on these fractures is close to asymptomatic screening. It notes that not everyone will benefit from the knowledge or the treatment of detected fractures. There may also be additional resource needs including more diagnostic and follow‑up tests and using staff and healthcare funds that could be used elsewhere.
Costs
Technology costs
Zebra‑Med provides the technology with a yearly license fee based on the annual volume of the site (total number of scans done at the clinical site). The solution can be sold under the Bone Health AI Solution package. Prices range from £38,000 to £90,000 every year, depending on the volume of scans done at the site using the technology.
The company states that installation of HealthVCF is done through integration with the PACS and that once it is installed other options can be added without additional technical work. Zebra‑Med's imaging analytics engine can be installed as an on-premises or cloud-based service. The cost of the technology covers training provided by the company.
Costs of standard care
Fracture risk assessment tools such as FRAX or QFracture are available free of charge. The average cost of a DXA scan is £72 (RD50Z; NHS reference costs 2019/20).
The average cost of a CT scan in adults can range from £83 to £115 (NHS reference costs 2019/20). Screening for fracture risk using CT scans is not currently recommended. CT scans would not be done as part of the current osteoporosis care pathway but for a different medical reason.
Resource consequences
The technology would be used alongside standard care and would cost more than using standard care alone. There may be costs savings if the device results in early detection of and improved management of fractures or fracture risk in people with osteoporosis. There is no published evidence to support this.
The company states that they provide a one‑day training session for radiologists and IT administrators, which is included in the cost of the software.