By combining this technology with an optical dye, tumors might be targeted more precisely. Due to its high resolution and sensitivity, it is expected to offer breast cancer patients a less aggressive, more patient-friendly follow-up examination. Today, patients with inconclusive results from traditional exams may need to undergo the invasive procedure of a biopsy.

Finding a more precise, patient-friendly way to screen for breast cancer through optical imaging are Royal Philips Electronics and Schering AG, Germany. The companies announced the formation of an alliance to develop medical equipment and associated contrast agents for optical imaging.

The announcement was made by Jouko Karvinen, CEO of Philips Medical Systems, and Dr. Hans Maier, head of Diagnostic Imaging, Schering AG, at the 91st annual meeting of the Radiological Society of North America (RSNA) in Chicago, recently.

The initial focus of this joint venture is to develop optical mammography for diagnosing breast cancer. It will combine Schering’s omocianine (SF-64) optical agent with a Philips optical scanner.

According to Mr. Karvinen, optical imaging will reduce biopsies which usually follow the detection of breast lumps.

Approximately seven million biopsies are performed annually around the world. Only 1.1 million are confirmed cancer cases.

According to Dr. Maier, optical mammography with the use of the new optical agent, now in Phase I clinical trials, will eliminate a woman’s exposure to harmful radiation. Since diagnosis is within hours instead of two to three weeks (as typical for biopsy results), it can offer early solutions that will add to the benefits of early detection.

Significantly, the technology will also offer a more comfortable alternative to X-ray mammography – the current standard for breast cancer screening – which involves flattening the breast between two plates to get as much coverage of tissue that is close to the chest wall. This is because X-rays travel in straight lines.

In optical imaging, it is possible to use diffusely scattered light to reconstruct an image of the breast without having to compress the breast to get information on tissue near the chest wall.

"We are very excited to team up with a leader in the contrast agent industry. Schering has strong capabilities in pharmaceutical R&D, and is clearly out in front of the new field of contrast agents for optical imaging. We also believe this collaboration builds on Philips’ patient focus of coming out with advanced, patient-friendly approaches to preventing and treating serious diseases like breast cancer," said Mr. Karvinen.

Both companies will also explore the emerging field of molecular imaging, looking at how to develop dyes that can potentially target breast tumors at the molecular level.

It is expected that the products will be commercialized early 2010.

About optical imaging

Optical imaging – also called optical molecular imaging – takes advantage of the fact that upon radiation with laser light of different wave-lengths, diseased tissues have different absorption characteristics.

This uses light to generate contrast. After the contrast agent is injected, if the tissue is imaged with near-infrared light, it emits a fluorescent light that can be measured with special detectors. Elaborate computer reconstruction algorithms convert these signals into three-dimensional images. The method does not involve any harmful radiation. If one adds targeting molecules to the dye, one can do molecular optical imaging that images certain diseased cells. More advanced research focuses on "smart dyes" that only start to light when they have docked onto their target cells.

Contrast agents

Contrast agents, sometimes referred to as "dyes," are used with a variety of medical imaging techniques to highlight organs and tissues by increasing the contrast with surrounding tissue, which make them easier to see. They are used with many types of imaging technologies like cardiovascular X-ray, computed tomography (CT), magnetic resonance imaging (MRI), Single Photon Emission Computed Tomography (SPECT) and positron emission tomography (PET). The high resolution images help clinicians clearly pinpoint abnormalities and provide accurate diagnosis of potential problems with less invasiveness to the patient.

Contrast agents are administered either as a drink, injected or delivered through an intravenous line or enema. Most contrast agents are absorbed harmlessly by the body, or expelled through urine and bowel movements.

The future of optical imaging

The key to beating many diseases is detection before even symptoms appear. Technological advances, such as optical imaging, are expected to contribute to a future in which disease is detected and treated at the cellular level.

Imaging of molecular activity is at the forefront of current research efforts to detect and study cancer non-invasively. The development of related technologies are helping researchers accomplish important goals in securing the future of optical imaging: Improvement of light penetration, image resolution, and the quantification and localization of disease. (Report developed from the background information provided by the Philips Public Relations staff to journalists who visited the RSNA exhibit in Chicago.)