Dr. M. Victoria Marx
The future of interventional radiology
April 01, 2019
by John W. Mitchell
, Senior Correspondent
Dr. M. Victoria Marx, 2018-2019 president of the Society of Interventional Radiology, has witnessed a transformation in interventional radiology and sees the pieces coming together that will push the specialty into new and uncharted territories.
The evolution of interventional radiology has been driven to a large degree by medical imaging technology advancements. Marx, who is also a professor of clinical radiology, vice chair for education and director of the diagnostic radiology residency training program at Keck Medicine of USC, cited examples including the development of cone beam CT to allow CT in the fluoroscopy suite and the increased use of intravascular ultrasound to improve the precision of vascular procedures such as transjugular intrahepatic portosystemic shunt (TIPS).
“Before intravascular ultrasound, we made transhepatic needle passes with fluoroscopic guidance alone; this was very imprecise,” said Marx, of performing a TIPS procedure. “With the concurrent use of intra-vascular ultrasound in addition to fluoroscopy we can turn what had been five or six passes of a big needle through the liver into one pass. This means less risk and less radiation exposure for patients.”
Hybrid rooms that include angiography and CT for complex interventions have also emerged to help advance the quality of care that interventional radiologists can provide. Meanwhile, 3D imaging capabilities are being introduced with superior views over the 2D standard of many years.
“You might be threading a catheter out and you know you need to turn anterior, not posterior, although this might not be immediately obvious on a 2D image,” Marx explained.
Augmented reality is another new tool that is poised to push interventional radiology forward, where providers can use equipment such as Google Glass to “superimpose previous 3D imaging on the patient so that you use less fluoroscopy.”
Artificial intelligence will help elevate interventional radiology as well, but not in the same way it’s being deployed by her colleagues on the diagnostic imaging side. Marx observed that early work in diagnostic imaging has been to find common predictable abnormalities – such as pneumothoraces on chest X-rays – and to support a better prioritized worklist. On the IR side, she predicts the role of AI is going to be more related to information gathering, information sharing, and decision-making.
“If you have a patient in the clinic that has a particular type of tumor with these types of markers, which is better: ablation, immunotherapy, or chemoembolization?” Marx offered, as an example. “We can ask AI, and it will be able to give those answers quickly without having to do a time-consuming literature search … I think it will make treatment algorithms of higher quality and more uniformly carried out.”
Looking at the next decade, Marx projects a higher growth rate in interventional radiology and credits that trajectory to a decision made in 2012 by the American Board of Medical Specialties to recognize interventional radiology as a separate primary specialty, not just a subspecialty of diagnostic radiology.
What that means, she said, is a student can decide to pursue interventional radiology as a residency straight out of medical school, working in an interventional radiology program with dedicated faculty mentors and teachers over a sustained period of time.
“We are already seeing a very high level of interest in interventional radiology, and it's attracting a high caliber student interested in the patient care and procedural aspects of minimally-invasive image-guided treatment. It appeals to medical students who want to be directly in charge of decision-making for patient care,” said Marx. “Also, people will be in IR training for six years not just one year, which will move the scholarly activity and research forward by leaps and bounds. High-end academic programs will get NIH training grants and increase the sophistication of the research in our field.”