Hybrid medical imaging is exactly what its name implies. Two or more types of medical imaging are used together to create a new medical imaging technique. Hybrid medical imaging allows radiologists to take advantage of the benefits of each type of imaging, and in some cases, the union of two imaging types creates a powerful advanced medical imaging modality that is better than the sum of its parts.
Some hybrid imaging techniques excel in bringing out anatomical details, and other techniques allow radiologists to combine both structural and molecular imaging. For example, PET/CT imaging was named “Medical Invention of the Year” in 2000 because of its ability to show molecular processes in vivo with a simultaneous view of anatomical location.
Current types of hybrid imaging include:
• PET / CT
• Single-photon emission computerized tomography (SPECT) / CT
• MRI / PET
• MRI / SPECT
• Ultrasound / MRI
• Ultrasound / CT
• MRI / CT
Advantages of Hybrid Imaging
Hybrid imaging allows radiologists to use the strengths of multiple image types at once. This can result in better diagnostic accuracy, improved monitoring of interventional radiology procedures, more personalized and individualized medicine, and in some cases, reduced exposure to ionizing radiation.
As just one example, SPECT / CT can be used for better diagnosis of foot osteomyelitis in diabetic patients. This combined type of medical imaging offers excellent anatomic and spatial resolution, results in fewer false positives from previous injuries, trauma, or surgery, and allows podiatric specialists to develop an infection severity score to help predict clinical outcome. Moreover, SPECT / CT allows response to therapy to be monitored closely.
Two Image Types, One Contrast Agent
Along with hybrid medical imaging techniques, there has been research into creating contrast agents that can work with two kinds of imaging at the same time. For example, dual-mode contrast agents for ultrasound / MRI hybrid imaging are being investigated. Ultrasound contrast agents are typically gas-filled microbubbles with polymeric shells. Researchers have found a way to anchor super-paramagnetic iron oxide nanoparticles onto the bubble shell so that the contrast agent would work with MR imaging at the same time. They also tried embedding the iron oxide nanoparticles inside the bubbles. When tested, the microbubbles with the iron oxide nanoparticles attached to the external shell structures were determined to offer better contrast with ultrasound and MRI at the same time.
Hybrid Medical Imaging for Acute GI Bleeding
One example of exploration of the use of hybrid medical imaging has been in localization of the site of acute GI bleeding. Researchers at the Cleveland Clinic reviewed cases of acute GI bleeding in patients who had SPECT / CT imaging done and found that the technique was 100% accurate in identifying the location of the bleeding source. This was found to be a big improvement of using Planar 99mTc-labeled RBC scintigraphy, which has limited utility in localizing bleeding sources, particularly in patients whose GI anatomy has been surgically altered. The use of SPECT / CT for finding the site of GI bleeding could mark a significant improvement in clinical care by eliminating the ambiguity of Planar 99mTc-labeled RBC scintigraphy, and could eventually become routine practice in acute GI bleeding cases.
Just as two heads are often better than one, two types of medical imaging used together can be better than either one used individually. Hybrid medical imaging can offer better anatomical definition and can even allow molecular processes to be viewed in their anatomical context, providing radiologists with more useful information. Patients can benefit from quicker, more accurate diagnosis.
South Florida Body Imaging Specialist: Dr. Richard Spira
SteleRAD is owned and operated by Board-certified radiologists. With several decades of experience in all radiology subspecialties, SteleRAD’s radiologists provide outstanding services to South Florida hospitals, medical imaging centers, and physician practices
Dr. Richard Spira is one of SteleRAD’s Body Imaging Subspecialty Radiologists. He also specializes in neuroradiology, and is certified by the Board of Cardiovascular Computed Tomography.
Dr. Spira was a clinical fellow in the Department of Radiology at Harvard Medical School, and has experience in academia as a Clinical Associate Professor at University of Florida College of Medicine. He has published many works made various presentations on his research in cardiovascular radiology. To learn more about Dr. Spira and the SteleRAD body imaging team, click here.