by Cat Vasko

· Philips Testing World’s First CAD Tool for ND Diseases
· Going Global with Breast MRI: Aurora Imaging Expands into Asia
· Safety Alert: ACR Releases White Paper on Radiation Dose in Medicine

Philips Testing World’s First CAD Tool for ND Diseases

The Philips-UKE CAD system automatically interprets PET brain scans of patients suspected of having an ND disease. This screenshot shows the interface of the CAD system automatically interpreting brain scans.

Philips Medical Systems, Andover, Mass, in conjunction with the University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany, has developed a computer-aided diagnosis (CAD) system for neurodegenerative (ND) diseases. The new diagnostic technique, which works on combined PET/MRI scans, is currently undergoing clinical evaluation at UKE.

“In the near future, there will be an increasing demand for early and accurate diagnosis of ND diseases,” explained Ralph Buchert, PhD, of UKE’s Department of Nuclear Medicine. “The number of elderly people will increase, and age is the number one risk factor for these diseases. There will also be attempts to cure these diseases, but if drugs are to work optimally, they must be given as early as possible.”

ND diseases are generally characterized by pathological changes in the brain, including changes in glucose metabolism. Patterns can be detected in the way these changes occur. “We try to differentiate ND diseases from the pattern of changes in glucose metabolism,” said Buchert. “We have disease-specific databases, including one for Alzheimer’s, one for frontal temporal dementia, and so on. The system performs an analysis to see which of these databases the symptoms fit the best.”

The database was compiled from data acquired in the nuclear medicine department at UKE from 2000 on; data was subsequently validated by clinical follow-up prior to inclusion in the database.

“Applying the CAD system to data in our department, results suggest that it has a sensitivity of 90% and specificity of 70% to 80%,” Buchert said. “We think that by integrating further modalities, such as FDG-PET, the system might be better than these numbers.”

The CAD system developed by Buchert and his colleagues at UKE works on both PET and MRI images for accurate differential diagnosis. UKE is using sequential PET-MRI, and Buchert explained that he did not expect tremendous advancements from using a device that would perform studies in the two modalities simultaneously. “The only advantage for this application is that the MR and PET images are aligned automatically,” he noted. “But we have very good software tools to perform this alignment. The brain is a very simple object.”

In fact, the CAD system does not even require that an MRI be performed. “It’s an omnivore,” Buchert said. “It takes whatever information it can get. If there’s no MRI, it uses different algorithms to perform the analysis based on FDG-PET alone. Sensitivity and specificity may decrease, but this has yet to be shown. We do know that MR adds anatomical information, which can be used to improve standardization. MR can also detect volume loss, and this might indicate atrophy.”

The clinical evaluation is running the CAD system alongside UKE’s existing dementia diagnosis procedures with the aim of fine-tuning the system’s ability to detect and differentiate the three most common types of ND disease: Alzheimer’s, Lewy body dementia, and frontotemporal dementia.

Going Global with Breast MRI:

Aurora Imaging Expands into Asia

On June 18, Aurora Imaging Technology Inc, North Andover, Mass, announced the establishment of wholly owned subsidiary Aurora Asia. The company is the manufacturer of the Aurora 1.5T Dedicated Breast MRI System, which is the only FDA-approved system designed to fight breast cancer.

In recent years, the rate of incidence of breast cancer in Asia has risen dramatically; it is now the leading cause of cancer death in women. Data from the Chinese Anti-Cancer Association (CACA) shows that both incidence and death rates of breast cancer in major Chinese cities rose by nearly 40% in the last decade. CACA ascribes the increase to several factors, including a younger peak age in Asia than in Western countries, between 40 and 50; the fact that the majority of Asian women have dense breasts; and the fact that dense breasts are particularly difficult to diagnose using mammography.

“Asian women are in dire need of access to the most effective breast imaging technology, such as MRI,” said Olivia Ho Cheng, president and CEO of Aurora. “By making our Aurora Dedicated Breast MRI System available, we increase the potential to detect cancer at its earliest, most treatable stage. Just as our company is devoted to the advancement of MRI technology for breast imaging applications, we are also devoted to ensuring that Asian women have access to the best possible breast imaging system.”

Aurora Asia’s president is Pai-Jung Huang, MD, formerly Aurora’s International Clinical Director. “The Asian economy has enjoyed rapid growth in recent decades,” Huang noted. “Unfortunately, breast cancer has also become a more pervasive problem. The silver lining is the rising and intense public education that has led to a greater awareness among Asian women about the nature of this disease and the importance of early detection.”

Safety Alert:

ACR Releases White Paper on Radiation Dose in Medicine

In the hope of educating “all stakeholders” in the principles of radiation safety and appropriate imaging utilization, the American College of Radiology (ACR) has released a white paper focusing on radiation dose in medicine. Published in the May issue of the Journal of the American College of Radiology (JACR), the set of recommendations is intended to help counteract medical and societal trends contributing to any increased radiation dosage Americans may experience as imaging becomes more and more important as a diagnostic tool.

“Although there are currently no data showing that high-dose medical diagnostic studies such as computed tomography and nuclear medicine have actually increased the incidence of cancer, a 2004 study suggested that medical exposure might be responsible for approximately 1% of the cancer in the US,” the paper notes. “This rate can be expected to increase on the basis of the higher number of examinations performed today. On the other hand, as the use of medical radiation has increased, the incidence of some cancers has decreased.”

The paper proceeds to not only make suggestions for how to more accurately modulate dosage, but also lay down standards to benchmark good practices and identify patients who may have received high levels of radiation from frequent imaging exams.

“The issue of radiation exposure associated with diagnostic imaging should be reinforced for nonradiology residents during their postgraduate years,” it says. “Although core competencies for residents typically address patient safety issues, they generally lack the curriculum content specific to radiation safety.”

The paper also suggests that the ACR “proactively sponsor a summit meeting between leaders of radiology and emergency medicine to address the growing issue of increasing radiation exposure to patients due to the overutilization of medical imaging.” Additional recommendations say the ACR should aim to:

  • Support the current multiorganizational effort to improve radiology resident training in medical physics.
  • Include additional questions on radiation safety and patient dose in its Annual In-Training Examination.
  • Request that the American Board of Radiology consider requiring at least one self-assessment module on patient safety to include radiation dose every 10 years as an integral part of the maintenance of certification.
  • Develop and implement maximum radiation dose estimate pass/fail criteria for the ACR CT Accreditation Program.
  • Review and update the CT Accreditation Program’s recommended scanning protocols on a routine basis and make them available on its Web site.
  • Request that the editor of the JACR add a monthly column on patient safety (to include radiation exposure issues).