Doctors at a community hospital review X-ray films hoping to better understand the cause of a patient’s symptoms . . . a cardiologist completes an angiography confident that she knows the severity of disease involving her patient’s heart . . . a man awaits his discharge from the hospital outpatient centre having completed the procedure that may help him beat prostate cancer with a minimum of embarrassing side effects . . . using a Gamma camera and injected radiopharmaceutical, a radiologist evaluates blood flow in the heart of a patient who has been experiencing chest pain.

These cases represent only four of the millions of patients who share a connection with a company committed to finding innovative diagnostic and therapeutic solutions in cardiology, neurology and oncology. The patients have all benefited from medical diagnostic and radiopharmaceutical imaging products.

Medical diagnostics used in X-ray imaging, computer tomography (CT) scanning, magnetic resonance imaging (MRI) and radiopharmaceutical imaging are, in general, ingested or injected into the bloodstream to enhance or produce images of the structure or functioning of body organs during diagnostic imaging procedures. These diagnostic images enable physicians more accurately to detect, diagnose and treat diseases and are changing the way medicine is being practised.

For over half a century, scientists have repeatedly broken new ground with innovative medical diagnostic products used to enhance visualisation. The result is safer, more comfortable procedures for the patient and better value for the healthcare provider. In fact, over 600 million medical diagnostic procedures are performed every year in hospitals around the world. Last year over 100 million scans were performed with a medical diagnostic product worldwide, generating over £2.5 billion in revenue for the manufacturers. As the new millennium begins, the global pharmaceutical marketplace is poised to receive new medical diagnostics and therapies to the arsenal of products available to help doctors help patients live longer and healthier lives.

Geographical split of medical diagnostic market sales

Nycomed Amersham, Mallinckrodt/Tyco, Schering, Bracco and DuPont, together with their respective licensees, are the major players in this market, with more than 90 per cent share between them.

Global medical diagnostic market share by manufacturer²

There are four main medical imaging modalities – X-ray (including computer tomography CT), magnetic resonance imaging (MRI), radiopharmaceutical imaging, and ultrasound. Radio-pharmaceutical imaging always requires a diagnostic product, while the other three modalities can be used with or without diagnostic product(s), depending on the procedure. However, the procedures are increasingly benefiting from the clarity added by the diagnostic product. Each modality is evolving to meet a growing list of demands placed upon it by modern healthcare requirements.

X-ray medical diagnostic market share by manufacturer²

X-ray scans are the most frequently performed imaging procedures covering all body areas. The simplest implementation of X-ray imaging is ‘plain film imaging’, such as a chest X-ray, which is the most widely used approach and forms the entry point for the diagnostic workup. Over 400 million plain film X-rays are generated every year. The next most common X-ray imaging approach is computer tomography, better known as CT, which allows cross sectional imaging of the body, with exquisite depiction of anatomic detail. There are about 33,000 CT instruments installed worldwide. Approximately 40 per cent of the CT scans have involved the use of medical diagnostic products. In addition, X-ray is used in conjunction with medical diagnostic products to obtain realtime images of the blood vessels and other structures that are highlighted by the presence of these products.

One of the primary advantages of X-ray imaging is the inherently simple basis of image contrast, which is the absorption of X-ray. For this reason, it has become the modality of choice in the radiology clinic. X-ray imaging can be used to image virtually every part of the body and is used for diagnosing cancer, heart disease, circulatory disease, respiratory disease, as a surgical aid and to follow the effects of treatment. More than 60 million procedures are done with medical diagnostic products around the world every year, generating sales of about £1.2 billion. The non-ionic products account for about 90 per cent of the total medical diagnostic sales in the EU, Japan and the US.

Of all the X-ray imaging methods, CT has had the most impact on the medical diagnostic market. The large installed base, the rapid development of the scanner technology, and the non-invasive nature has propelled this modality to the forefront. The installed base of CT instruments is still growing at the rate of approximately five per cent a year. During the last two years, innovations in X-ray detector technology have provided the capability to perform subsecond imaging of millimetre thin slices. This advance has opened up a host of new applications, such as blood vessel imaging, blood clot imaging, calcifications, large field imaging, and the ability to separately image the different vascular phases of medical diagnostic products.

Another significant area of development is the advent of compound modality instruments. For example, instruments that can generate images of radiotracer uptake and CT images have been launched. These will allow the co-registration of low-resolution functional images of highly selective radiotracer products with high-resolution CT images of the anatomy to provide information on early detection of disease, surgical planning and radiotherapy. These developments will further aid in the growth of the CT modality and hence the medical diagnostic market.

MRI medical diagnostic market share by manufacturer²

While X-ray is the oldest and most established imaging modality, MRI is the newest. During the last few years, MRI has emerged as the imaging method of choice for many applications. For example, MRI is routinely used in imaging the central nervous system, particularly in detecting cancers in the brain. More recently, MRI has found use in imaging the blood vessels and depicting brain regions affected by stroke. Although there are some similarities to the images obtained using CT, MRI is complementary to CT in many respects. MRI allows imaging without using X-rays and in any arbitrary plane, making it better suited for some regions of the body. While CT excels at demonstrating bony regions in great detail, MRI can reveal differences in soft tissue. For these reasons both MRI and CT have experienced concurrent growth in usage.

There are more than 13,000 MRI instruments installed worldwide. This figure is expected to grow by about five per cent each year for the foreseeable future. Close to 40 million MRI scans are performed each year. Roughly a fourth of these require the use of a medical diagnostic product, generating sales of about £265 million. Every category of contrast-enhanced MRI has experienced growth and this is expected to continue. Advances in scanner technology have made magnets cheaper, easing the cost barrier. Higher field open magnet designs have recently been launched paving the way for newer applications. Enhancements in gradient hardware have allowed faster scanning. For example, the entire lung can now be scanned in less than five seconds. Improvements in computer hardware and software have further helped in increasing utilisation of the imaging data generated.

The advances in MRI medical diagnostic products are driving, and are driven, by new clinical applications. Some of the applications that are expected to see significant growth in the coming years are cardiac imaging, vascular imaging, ultrafast imaging for evaluating function and breast imaging. Almost all of the current applications in contrast MRI are based on the non-specific extracellular gadolinium-based products. These products can freely diffuse to regions outside the blood vessels. Other medical diagnostic products with specific properties are in development. Diagnostics that are confined to specific compartments such as vascular and air spaces are examples that could spawn new clinical applications and expand the market. Also on the horizon are medical diagnostic products that target specific tissues such as lymph nodes and blood clots. The ability to identify high-risk patients in the not too distant future, along with the need for accurate anatomical and functional information, will drive the market for these new products.

In summary, MRI is poised to grow further during the next few decades as a consequence of continued innovation.

Radiopharmaceutical medical diagnostic market share by manufacturer²

The ability to visualise organ function is the unique strength of radiopharmaceutical imaging. While other imaging modalities will show whether an organ is structurally normal or abnormal, radiopharmaceutical imaging will determine if that same organ is functioning as it should. Targeted medical diagnostic products labelled with a radioactive marker (radiopharmaceutical ) are used to visualise biological processes so that what goes on inside the body can be seen from the outside. The patient does not even have to remove his/her clothes! All that is needed is a Gamma camera – and there are more than 12,000 of those in the US alone.

Radiopharmaceuticals provide more functional data than any other diagnostic imaging method. In the heart, for example, coronary angiography, the process where blood vessels in the heart are visualised using X-rays, can show if there is a blockage in a vessel. Nuclear cardiology can show the effect of that blockage on the heart’s function. This is essential information for the cardiologist. Almost 10 million patients benefit from the use of radiopharmaceuticals every year. In total more than 25 million radiopharmaceutical imaging procedures were carried out across the world in 2000, for the diagnosis of most of the major diseases of our time.

The global market is worth in excess of £1 billion and is growing at about seven per cent per year. Most recent innovations rely on the visualisation of precise cellular activities. Such state of the art science is likely to result in new products that can visualise subtle changes in organ function, enabling early diagnosis, at a stage when treatment is most beneficial, to become the norm.

Indeed, it is already possible to see changes in brain function due to Parkinsonism even before the patient has symptoms. This type of assessment may be useful in the future for those individuals considered at high risk of developing Parkinson's disease or a related syndrome.

The future of radiopharmaceutical imaging is promising. With the advent of new products to examine key functional changes associated with cancer, heart disease and various neurological disorders, radiopharmaceutical imaging is at the forefront of innovation in molecular diagnosis.

1. Includes European Union, Norway, Switzerland, and Iceland. 2. Market share data provided in this article includes sales by licensee partners. Data presented in this article are primary data collected in accordance with the Best Practice Market Submissions and is revised at least twice a year.

Imaging market (continued) »