Interventional radiologists help patients by integrating a trinity of qualities: imaging expertise, procedural skills and clinical care. With the emergence of new, disruptive technologies, IR is better positioned than ever to better serve patients and treat disease.
Diagnostic imaging
Advances in diagnostic imaging offer the ability to characterize disease processes in ways that were previously impossible.
- Dual-energy CT scans use different energy levels to produce different attenuation of tissue. This technology can differentiate types of renal stones, calcified plaque vs. iodine contrast within vessels and characterize previously “indeterminate” abdominal lesions.
- Four-dimensional phase-contrast magnetic resonance flow imaging (4D flow MRI) collects data in all three spatial directions relative to time to provide data on complex blood flow patterns and quantification of flow parameters. This can be used to quantify regurgitant and stenotic jets in cardiac valvular disease, shunt flow directionality, and identify areas of high vorticity and wall shear stress in aneurysms at risk of rupture.
- Perfusion imaging technologies provide real-time visual assessment of tissue perfusion.
- Artificial intelligence–assisted diagnostic imaging and deep learning algorithms, though controversial, offer the promise of improved diagnostic accuracy and efficiency.
IR procedures
In the procedural realm, new techniques and technologies provide multiple treatment options to patients who previously had few.
- 3D printing is increasingly used for pre-procedural planning models, custom prosthetic implants, patient education and physician simulation training (see bit.ly/irq3d).
- CT-ultrasound fusion and MRIultrasound fusion guidance can increase targeting confidence during biopsies or ablations.
- There are multiple chronic total occlusion (CTO) crossing devices available that use a fast spin torque handle to cross CTOs. Another crossing device on the market uses optical coherence tomography imaging on the tip of a rotating crossing catheter to provide visual confirmation of luminal passage.
- One ultrasound-guided lumen re-entry device utilizes an intravascular ultrasound (IVUS) transducer to provide direct visualization of the re-entry needle position and lumen location during subintimal crossing.
New percutaneous options
There are now percutaneous options in some conditions previously reserved for surgical management.
- For the treatment of end-stage renal disease, one percutaneous arteriovenous (AV) fistula system uses a 4- or 6-French magnetic catheter system to create an AV fistula using only endovascular technique.
- In patients with long, complex superficial femoral artery (SFA) occlusions, another company’s system offers a percutaneous bypass treatment in which multiple stent grafts traverse from the popliteal artery into the femoral vein and from the femoral vein into the SFA in a continuous, overlapping fashion to bypass an SFA occlusion.
- For the treatment of end-stage critical limb ischemia (CLI) in which all other revascularization efforts have been exhausted, one device uses an antegrade 7-French arterial ultrasound catheter to connect with a 5-French retrograde posterior tibial vein ultrasound catheter to bypass an arterial CTO. Next, a nitinol stent is placed from the posterior tibial vein to the patent posterior tibial artery to route blood into the deep venous circulation, essentially providing arterial flow to the deep veins to oxygenate the ischemic foot.
Communication
Interventional radiologists achieve full potential when practicing clinical care and effectively communicating with patients.
- High-quality, HIPAA-compliant, video-to-video telecommunication allows for clinical communication throughout the world, and even into space, as used by NASA.
- There are also programs that provide interactive, multilingual communication for nonvocal and critically ill patients.
Conclusion
Every year reveals new emerging technologies that require further study to evaluate effectiveness but, nevertheless, have tremendous potential to heal patients, reduce suffering, improve quality of life and ultimately help achieve IR’s mission of providing and improving high-quality patient care.
