Note: Market numbers within text represent internal company estimates unless stated otherwise.

Despite significant advances in the understanding of the underlying causes of disease in recent years, medicine still revolves primarily around the treatment of existing conditions following the appearance of symptoms. To select the most appropriate course of treatment for each individual patient, the physician first needs to make a correct diagnosis but must also establish the location, extent and severity of disease and determine a prognosis.

Medical imaging is uniquely able to provide this information and is a key component of modern healthcare. In 2002, approximately 800 million medical imaging procedures were performed worldwide. Of these, approximately 120 million scans were enhanced or made possible with medical diagnostic products, generating revenues of over £2.8 billion. Medical diagnostics markets are demonstrating strong year on year growth and this is expected to continue.

There are four main imaging modalities – X-ray including computed tomography (CT), magnetic resonance imaging (MRI), radiopharmaceutical imaging and ultrasound. Radiopharmaceutical imaging always requires the use of a diagnostic product, while the other modalities may or may not use a contrast medium to enhance the image, depending on the procedure. The choice of technique depends upon a number of factors including the type of diagnostic information needed, instrument availability, physician preference, and cost/benefit considerations.

For the management of heart disease, for example, the cardiologist might use radiopharmaceutical imaging to determine how well the heart muscle is being perfused with blood, contrast-enhanced ultrasound to improve endocardial border delineation, and X-ray to perform a coronary angiography of the blood vessels. All of these examinations would normally use a medical diagnostic product.

Market developments in 2002
In the US, the rapid growth of the over-50 population where more diagnostic procedures are required, combined with the growing ability to do more procedures due to technological advances in the equipment sector, are expanding the need for medical diagnostics. Pricing has been maintained at fairly stable levels.

In Europe, the tough reimbursement environment continues to affect pricing. The markets are still dominated by state funding, although the private market is increasing. However, the installed hardware base in Europe is expanding and this will allow further volume growth.

The Japanese diagnostic pharmaceutical market continues to show modest volume growth but the overall environment remains challenging due to ongoing healthcare reform measures and government-mandated reimbursement price cuts.

Amersham Health, Bracco, Tyco Healthcare (Mallinckrodt Imaging), Schering and Bristol-Myers Squibb (BMS) Medical Imaging (formerly Dupont), together with their respective licensees, are the major players in the medical diagnostics market, with more than 90 per cent share between them.

Company	Global market share (%)
Amersham Health	38
Bracco	18
Tyco/Mallinckrodt	14
Schering	12
BMS/Dupont	12
Guerbet	2
Others	4

Market drivers
Increasing demand for medical diagnostics is being driven by the ageing population and the rise in prevalence of age-related diseases such as cancer, Alzheimer’s disease, Parkinson’s disease, stroke and heart failure. These diseases represent the highest cost burden to healthcare systems in industrialised nations, and there is tremendous pressure to develop tests that can assist in earlier diagnosis and aid selection of the most appropriate treatments in order to reduce costs.

Prevalence and economic cost of major diseases in the US
(Source: Pharmaceutical Research and Manufacturers of America, 2000)

This has led Amersham Health to focus its product development on disease states, rather than a modality-driven approach, and to include cardiologists, neurologists, oncologists and internal medicine physicians in its customer base, in addition to radiologists, hospitals and purchasing organisations. The aim is to enable physicians and their patients – who are becoming better informed and expect to be included in decisions about managing their disease – to select the imaging procedure and diagnostic product they feel is most appropriate in each case.

Scanner technology is also making significant advances. The emphasis is on improving the speed and functionality of instrumentation, allowing increased numbers of procedures per unit.

Looking further ahead, our rapidly increasing knowledge of genomics raises the very real prospect of being able to be truly proactive in predicting and preventing disease, and to determine which medication is best suited for each individual. Medical imaging technologies which can identify pre-symptomatic disease, increasingly through monitoring of the expression of genes and the function of the proteins for which they code within cells, will be key to delivering personalised medicine: finding the right therapy, for the right patient, at the right time, with the right outcome.

X-ray/CT medical diagnostics

Total scans	approx 630m
Enhanced scans	approx 75m
Market size	approx £1.4bn

X-ray is the most frequently performed imaging procedure covering all body areas and is often the entry point for the diagnostic work-up. X-ray computed tomography, or CT scanning, has had the greatest impact on the medical diagnostics market. CT scanning allows cross-sectional imaging of the body with exquisite depiction of anatomic detail, and is finding growing use in coronary angiography and interventional procedures. Approximately 40 per cent of CT scans currently involve the use of medical diagnostic products.

The development of multi-slice CT machines, which are capable of performing sub-second imaging of millimetre-thin slices of body tissues, has opened up a host of new applications such as blood vessel imaging and blood clot imaging, many of which require large volumes of medical diagnostic contrast media.

MRI medical diagnostics

Total scans	approx 40m
Enhanced scans	approx 10m
Market size	approx £320m
Number of MRI machines	over 15,000

Magnetic resonance imaging (MRI) is often the method of choice for imaging the central nervous system, particularly for detecting cancers in the brain and lesions in the spinal canal and spinal column. More recently, MRI has found use in imaging the blood vessels and depicting brain regions affected by stroke. Roughly 25 per cent of the MRI scans use a medical diagnostic product with every segment of contrast-enhanced MRI experiencing growth, and this trend is expected to continue.

New MRI contrast media are being developed for vascular imaging, cardiac imaging, visualisation of air spaces in the lungs, and for targeting specific tissues such as lymph nodes and blood clots. The ability to identify high-risk patients in the foreseeable future, along with the need for accurate anatomical and functional information, will drive the market for these new products.

Radiopharmaceutical medical diagnostics

Scans (enhanced)	approx 28m
Market size	over £1.1bn
Number of gamma cameras	over 15,000

Radiopharmaceutical imaging provides metabolic and functional information about diseases such as stroke, dementia, coronary artery disease and cancer that complements anatomical imaging such as CT or MRI. Radiopharmaceutical imaging always requires the use of a radiolabelled medical diagnostic product, which binds to and accumulates in the cells or tissues being studied, and the image is obtained with the aid of a gamma camera.

Recent innovations in radiopharmaceutical imaging enable the visualisation of precise cellular activities and subtle changes in organ function, such as changes in brain function due to Parkinsonism.

The latest advance in radiopharmaceutical imaging is positron-emission tomography (PET). PET, an advanced molecular imaging technique, can provide images of the entire body and visualises biochemical events at the cellular level. It is an extremely sensitive technique for the early detection of tumours and metastases, and PET procedures are now reimbursed by Medicare in the US for seven types of cancer. The clinical application of PET technology is a rapidly growing emerging market, with around 300,000 procedures performed in the US in 2002. Continued advances in instrumentation and improvements in PET chemistry could expand its use into other significant markets, eg. the management of neurological conditions such as Alzheimer’s disease.

Another significant development is the advent of compound modality instruments combining high-resolution CT images of the anatomy with low-resolution functional (PET or SPECT) images during parts of the same imaging procedure. These enable more accurate localisation of disease and assist the planning of surgical interventions and radiotherapy. Such developments in so-called ‘fusion imaging’ are expected to fuel the growth of both CT and PET imaging.

Ultrasound medical diagnostics

Total scans	approx 140m
Enhanced scans	approx 0.5m
Market size	over £10m
Number of instruments	over 150,000

Ultrasound is used extensively by both hospital and office-based cardiologists to evaluate patients with known or suspected coronary artery disease. The vast majority of cardiac patients are screened by ultrasound, and in 2001 over 25 million ultrasound scans of the heart were performed throughout the world. However, results are often equivocal with patients frequently referred on to more reliable and expensive techniques (eg. CT and MRI).

Only a fraction of the ultrasound scans currently use a medical diagnostic product, the primary use being to improve the assessment of heart wall motion through endocardial border delineation, or visualisation of the surface of the heart muscle. The true utility of ultrasound in cardiology could be realised with the visualisation of myocardial perfusion. This will require advances in instrumentation along with advanced ultrasound diagnostic products, in order to obtain a reliable and robust imaging procedure. In radiology, contrast-enhanced ultrasound has the potential to differentiate between benign and malignant tumours in various tissues. Developments such as these would expand the ultrasound medical diagnostics market.

Radiotherapy market
The most significant therapeutic market for radioisotopes is prostate brachytherapy, a minimally invasive outpatient procedure in which radioactive iodine or palladium seeds are implanted within the prostate gland to irradiate the tumour. The mounting clinical evidence supporting the efficacy of this treatment was further underpinned in 2002 through two important studies, one relating to the treatment of high-risk patients with palladium¹⁰³ seeds in combination with external beam radiation, and the other demonstrating the benefits of Amersham’s Rapid Strand™ iodine¹²⁵ delivery system.

In the United States, around 40,000 patients each year, or 25 per cent of those presenting with early stage prostate cancer, are treated with brachytherapy seed implants. Slower market growth and increased competition, with the number of competitors rising from two in 1998 to 14 today, have resulted in significant pricing and market share pressure. In 2002, the US Medicare reimbursement system set a fixed cost for brachytherapy procedures and further changes will take effect in 2003, further intensifying the price pressures.

Brachytherapy is gaining acceptance in Europe and while only a small percentage of early stage prostate cancer patients currently receive seed implants, the market has substantial development potential.

Radiolabelled monoclonal antibodies are being developed for the treatment of several types of cancer. The antibodies target specific tumour cells and then attach to them, allowing the radioactive component to destroy tumour cells while sparing the surrounding healthy cells. 2002 saw the first of these compounds licensed by the US FDA for the treatment of non- Hodgkins lymphoma patients who have failed to respond to previous therapies.

Other radiotherapy products include strontium⁸⁹, which can target growing bone cancers and help to alleviate pain, and iodine¹³¹ for the treatment of thyroid tumours.