» The material travels through the body to the lungs, where its distribution through the circulatory system of the lungs can be imaged by an external gamma camera.

» The captured images is stored on a computer and can be analyzed by a physician to make a diagnosis.

» The principal agent used for lung imaging and the diagnosis of Pulmonary Embolism is composed of albumin macro-aggregates (or AMA), while the radioactive tagging agent is the industry standard gamma emitter Technetium 99m (Tc99m).

» AMA is a fine diagnostic tool, and it is used on a worldwide basis. Some of the more affluent and well equipped hospitals have taken to using Spiral CT scans as an alternative to Nuclear Medicine based lung imaging, but given the cost of such machines and the demands on their time, Nuclear Medicine based lung scans remain and are likely to remain the first choice for front line diagnostic testing for Pulmonary Embolism in the majority of hospitals throughout the world.

» AMA does however have some drawbacks. Its clinical utility is limited by its very nature; it is fundamentally unable to image the smallest blood vessels in the lungs; it can only produce static snapshot images of the state of the circulatory system, and it is known to cause damage to the lungs of patients.

» The medical community has long believed that the damage caused is far outweighed by the usefulness of the diagnostic information that AMA provides. Ideally there would exist a better agent; one that could image the smallest blood vessels in the lungs, that could also be used for dynamic imaging (showing how the circulatory system changes in real time) and with no health issues for the patient.

» Such a product is under advanced development at PulmoScience. It is safer than AMA, it does not damage the patient, and it provides substantially improved diagnostic information.

» This new agent is called PulmoBind.

» PulmoBind involves Molecular Imaging, and uses a totally harmless substance (Adreno Medullin) which is naturally produced by our bodies (and can be easily synthesized). This is bonded to a radioactive tracer element (Technetium 99, the most common and widely accepted radioactive tracer, and found in every nuclear medicine facility in every hospital worldwide).

» When injected into the patient, the bonded Adreno Medullin and Technetium 99 travels to the lungs where the Adreno Medullin preferentially binds to the inner walls of the blood vessels in the lungs. Its distribution is then imaged by using an external gamma camera.

» This process is very similar to the use of AMA; indeed, PulmoBind uses the same protocols currently used in AMA based diagnostic procedures. PulmoBind uses the same nuclear imaging gamma cameras to photograph the circulatory system and the same Tc99m as the gamma emitting tag.

» In changing from the potentially harmful AMA to PulmoBind, Hospitals will not have to change any procedures and will not be required to make any expensive investments in new imaging or capital equipment.

» Hospitals can carry out their diagnostic procedures exactly as they do at the moment, but by replacing the less effective agent (Albumin Macro-Aggregates) with the more effective and safer PulmoBind. Using PulmoBind will result in safer and better diagnostic information, along with the ability to image multi-events in one treatment session (some images not possible using AMA).

» Once injected into the patient, AMA travels through the circulatory system and then reaches the lungs. The AMA particles are larger than the small pulmonary vessels in the lungs through which they are travelling, and therefore become lodged in the capillaries and their distribution can then be imaged by an external gamma camera. Once lodged in these micro capillaries, the AMA will block them and effectively destroy those capillaries beyond the point of the blockage.

» In addition, being lodged in the capillaries, the distribution of AMA can only show a static snapshot of the state of the circulatory system as at the moment in which they became lodged. They can not show any dynamic changes to the circulatory system.

» Compare this to PulmoBind. PulmoBind is much smaller than the smallest micro capillary, and so causes no damage at all to the lungs. Further, as it will not have been blocked in the capillaries, PulmoBind is able to display any dynamic changes to the circulatory system of the lungs in real time.