"The potential of using more than one tracer and more than one isotope simultaneously means that more than one medical condition can be searched in one go--ultimately improving the diagnosis of cancer, heart and brain diseases," explained James A. Patton, professor of radiology and physics with the department of radiology and radiological sciences at Vanderbilt University Medical Center in Nashville, Tenn. "In addition, as the speed of this new D-SPECT camera approaches the imaging speed of computed tomography (CT), it will become economical to have functional and anatomic imaging in line (as a hybrid image) and in near real time for developing combined single photon emission computerized tomography (SPECT) and CT images," added the co-author of "D-SPECT: A New Solid State Camera for High-Speed Molecular Imaging."
"Patient health considerations and radiation safety standards limit the radiation dose that can be administered for the purpose of diagnostic imaging," said Patton. "In addition to this limitation, the low efficiency of existing SPECT imaging technology in collecting radiation imposes very long acquisition times of up to a full hour and sometimes more," he added. "This new camera technology enables acquisition times that are shorter by an order of magnitude (2 minutes vs. today's 20 minutes for a cardiac scan), better image quality (up to two times the image resolution) and the potential for new diagnostic procedures employing simultaneous multi-isotope imaging for more versatile diagnostics," he explained. "Due to its very high sensitivity (10 times higher) and definition (up to 2 times the re solution) and novel scanning design--together with usage of high-energy discrimination of the solid state detectors--this new technology can open the way to personalized diagnostics taking into account patient-specific physical information," noted Patton.
"For 50 years, physicists have been struggling with the inherent trade-off between spatial resolution and sensitivity associated with radionuclide imaging," said Patton. "D-SPECT collects photons with much higher efficiency (order of magnitude) due to usage of a split–scanning detector design capable of dwelling more on the organ of interest. This, together with radiation collection angles larger than in existing technology, constitutes a radical departure from the conventional Anger camera," he detailed. Besides providing improved statistics leading to better image quality and the potential for better and earlier diagnosis of diseases, the D-SPECT camera reduces the time a patient spends on imaging equipment, said Patton. Patients receive a lower radiation dose, and personalized scanning takes into account unique patient physiology and anatomy, he added. "Simultaneous imaging of a combination of radiopharmaceuticals can be used to define a specific disease signature leading to noninvasive biopsy," he detailed. The D-SPECT camera will provide "a potential breakthrough in organ-specific (heart) SPECT imaging," said George Zubal, SNM's Scientific Program Committee instrumentation and data analysis vice chair and associate professor of diagnostic radiology and technical director of nuclear medicine at Yale University in New Haven, Conn.
Researchers from Spectrum Dynamics, Haifa, Israel; Vanderbilt University Medical Center; Cedars-Sinai Medical Center, Los Angeles; Stanford University, Stanford, Calif.; and New York Presbyterian Hospital–Weill Cornell Campus, New York, N.Y., will now focus on specific clinical applications for the D-SPECT camera. "The first such application will be in cardiac perfus ion (blood flow to the heart), and a multicenter study is planned for the second half of this year," said Patton. Vanderbilt University Medical Center will be among the first four sites to experiment with the imaging camera, said Patton, who indicated that the imaging device is investigational, with Food and Drug Administration submission expected over next few months.