Molecular Imaging

Molecular imaging (also called nuclear medicine or nuclear imaging) can image the function of cells inside the body at the molecular level. This includes the imaging modalities of positron emission computed tomography (PET) and single photon emission computed tomography (SPECT) imaging. How does PET and SPECT imaging work? Small amounts of radioactive material (radiopharmaceuticals) injected into a patient. These can use sugars or chemical traits to bond to specific cells. The radioactive material is taken up by cells that consume the sugars. The radiation emitted from inside the body is detected by photon detectors outside the body. Computers take the data to assemble images of the radiation emissions. Nuclear images may appear fuzzy or ghostly rather than the sharper resolution from MRI and CT.  But, it provides metabolic information at a cellular level, showing if there are defects in the function of the heart, areas of very high metabolic activity associated with cancer cells, or areas of inflammation, data not available from other modalities. These noninvasive imaging exams are used to diagnose cancer, heart disease, Alzheimer’s and Parkinson’s disease, bone disorders and other disorders. 

Industry-academia relationship: The need to collaborate and disclose

The current economic crisis affects industry, but also academia, with decreasing federal funds available for medical research. Many of the brightest researchers create and invent novel approaches in academia. On the other hand, scientific discoveries by pharmaceutical, radiopharmaceutical and instrumentation companies frequently need to be tested and validated in collaboration with academia.

Surviving the Moly shortage: Investing in Alternatives

Over the past few years, the global nuclear medicine community has been plagued with shortages of medical radioisotopes, which is particularly detrimental for the oft-used molybdenum-99 (Mo-99)the parent isotope of technetium-99m (Tc-99m), the most widely utilized radioisotope in the world for molecular and nuclear diagnostic imaging studies. 

A Look Ahead: Inside Optical Imaging

Within the field of molecular imaging, there are quite a few techniques that are well established within routine clinical practice. Other techniques have earned the reputation of being powerful and innovative when it comes to experimental or preclinical research, but have had trouble translating into the clinic. That could be changing, particularly in the area of optical imaging.

PET/MRI: Where We Are, Where Were Going

The merging of PET and MRI is producing synergies far beyond the capabilities of two distinct imaging modalities. The sum is clearly greater than its parts, according to researchers using both preclinical and clinical PET/MRI prototypes, notably because scanning is simultaneous rather than sequential like its PET/CT cousin, and the excellent soft tissue visualization MRI offers. A clinical prototype is being used to study human brain tumors, and researchers predict integrated whole-body human PET/MRI scanners will be available in the next couple of years.

FDG-PET in Dementia Imaging: Whats Dragging Down Utilization?

PET imaging for Alzheimers disease has a fairly long history. As far back as the early 1980s, researchers realized that FDG-PET scans could show changes in brain activity indicative of Alzheimers disease. The Centers for Medicare and Medicaid Services (CMS), however, did not reimburse for the procedure. Consequently, when patients were referred for an imaging exam, clinicians more commonly ordered a SPECT study.

Non-FDG PET Tracers in Oncology

The constant drive to predict and characterize cancerous tumor response to therapy that is earlier, better and more specific, as well as the success of the PET tracer FDG coupled with an established and emergent worldwide PET infrastructure are generating greater interest in the utilization of non-FDG radiotracers for oncology. 

Business Practices

This issue of Molecular Imaging Insight features several discussions about Building the Business of Molecular Imaging. I believe it is important to note that clinical molecular imagingand here most prominently PET/CTis still in its infancy with regards to its utilization.

Soft Tissue Sarcoma: FDG-PET/CT Defines Treatment Responders, Non-Responders

The diagnosing, staging and monitoring of cancer benefits from early response assessment. This includes patients with high-grade soft tissue sarcoma (STS), malignant tumors, which develop from fat, muscles, nerves, joints, blood vessels, bones and deep skin tissues. Until recently, oncologists typically had to wait months to see if treatment for this rare, and often deadly, disease was effective. PET/CT has changed that scenerio. Researchers now can assess a patients response or lack of response to treatment within one week of completing the first chemotherapy treatment. This is good news for both physicians and patients; physicians can make quicker, more efficient and complete treatment evaluations and alterations which may mean a better quality of life for many sarcoma patients. Another plus for U.S. based facilities is that Medicare coverage for STS was just added for initial treatment strategy.