Virtual Reality (VR): Bringing CT to the Foreground of Surgery Prep

Pictured above is a surgeon viewing a CT scan for guidance while inserting a catheter. The x-ray is displayed at the patient’s bedside on a monitor. Developers hope to use Virtual Reality (VR) to virtually display a CT scan or x-ray, both for training purposes and to replace the monitor allowing easier viewing during surgery.

Virtual Reality (VR) has shown promise in displaying complex images in an immersive way. The Army, Air Force, and various police departments across the U.S. use VR to create training programs for specialized scenarios. Even businesses like Walmart and UPS are using VR to train employees on customer service, delivery routes and special safety circumstances. VR will revolutionize safety training, especially in industries where workers face a variety of scenarios. For this reason, medicine is one of the most important fields to integrate this technology. Medical staff from nurses to surgeons could train virtually to handle the pace, pressure and complexity of procedures.

The best application of VR in medical training is visualizing parts that may be too small or complex to view without using a microscope or cadaver. Systems like the central nervous or cardiovascular are impossible to view in a fully immersive way. Thus, VR makes the human anatomy much easier to study and less prone to error. CT scans, when viewed in an immersive virtual experience, further extend the specialist’s confidence and familiarity with the patient’s anatomy. In the same light, increasing the confidence level of practitioners has a positive effect on diagnosis and surgery prep. While common surgeries may not see immediate benefit, VR has larger implications for the most complicated and risky operations.

Virtual reality in aneurysm and coronary operations:

VR training is good for practicing highly precise surgeries, like on tiny arteries where a minor slip could be fatal. Surgeries dealing with artery aneurisms require heavy preparation specific to each patient’s anatomy. Virtual reality plays a vital role in the planning process, as surgeons can generate and inspect a recreation of the artery’s structure. Practitioners not only see but interact with the patient’s artery, identifying inflow and outflow arteries in a virtual setting. This makes all the difference in communication between radiologists, surgeons, other medical staff and the patient.

The photo above is a CT angiography (focusing on arteries) study on a human brain. These studies are extremely helpful when treating aneurysms and heart problems. With VR, practitioners can inspect and manipulate these scans in 3D before performing the operation in real time.

Cardiac radiologists have actively used VR in assisting with imaging, in one of the riskiest surgeries: coronary intervention. Full blockage of the coronary arteries is a large hurdle for catheter-based treatments for many reasons. Conventional coronary imaging techniques do not provide a complete picture of blocked arteries, adding further uncertainty to already unpredictable success rates. Surgeons from the Institute of Cardiology in Warsaw were able to use Google Glass to assist in coronary intervention. Normally, surgeons view CT scans on monitors alongside the operating table. Using a VR headset allowed the surgeons to see a 3D representation of the coronary artery without looking away from the patient.

This improves the surgeon’s guidance and operating efficiency, but also bypasses the cost of full CT suites and monitors. Mobile technology is experiencing heavy cost reductions, and is much more accessible than CT tech. As VR becomes proven in surgical use, mobile technology like glasses or headsets could bypass CT-monitor systems altogether.

VR in eye surgeries and diagnosis:

Optic nerves are difficult to study due to their size, as well as the delicacy of the human eye. Ophthalmology (the study of vision disorders) was advanced by leaps and bounds with the OCT scan, but they are far from perfect. It has become a common diagnostic method, but in its increased use, more and more errors are emerging. OCT scans are prone to false positives and negatives, where the color code of the scan is “tricked”. Red and Green are indicators of abnormal or normal tissue. Cases of severe nearsightedness sometimes throw off the OCT, which then shows opposite readings. User errors involving the setup of the OCT machine, or the patient’s head placement during the scan can also influence the outcomes of OCT studies.

A new virtual reality program enables OCT viewing with a retail VR device like the HTC Vive. Ophthalmologists can view and manipulate the OCT volume in 3D and can move it to any angle or position. In addition, they can draw markers along the OCT volume that indicate different segments of the eye (called “sectioning”). Some new research on sectioning focuses on using machine learning, but in surgery direct imaging displays trump automated methods. Visualizing the sectioning process lets ophthalmologists prepare for surgery by interacting with a lifelike recreation of the patient’s condition. Similarly. they could reduce the false results that plague OCT scans through more in-depth analysis. Researchers using a VR viewing tool can catch these errors before they lead to misdiagnosis or mistreatment.

The creators of this VR OCT viewer also tested the program for use in a simulated surgery. The VR tool was used in lieu of a microscope, as the surgeon could use the 3D display to navigate the optic structures. An assistant was needed to control the OCT scan so that the surgeon’s hands were free to operate. However, the process proved to be more effective as the surgeon did not need to stop and reference the OCTs for information. The VR headset is much less cumbersome than operating through a microscope and allows for better guidance with a live comparison of OCT volumes. This makes the procedure a more fluid and comfortable experience for the surgeon which will likely help improve outcomes.

Conclusion

VR may have popular uses in entertainment, but it has made significant headway in the field of medicine. Specifically, in the more complex, costly and dangerous operations where any help makes a difference. Surgeries aided by VR have improved guidance along with a more comfortable interface. Research and development on VR cost controls is extensive and always advancing. Producers intend on lowering headset prices vastly for sale to consumers. Mobile technology is more feasible to adopt in developing markets, where advanced CT setups with dedicated monitors are rare.

If costs can be reduced significantly, CT technology and surgeries that rely on it will be available on a wider scale. Proliferating medical VR can mean more preventative care on the issues that often go unaddressed like heart and artery conditions. Poor heart health and heart failure are some of the most common causes of death and are an issue in every population. Treatments for these conditions are often fully reliant the quality of the provider’s CT care, making VR an extremely important tool to ensure quality CT can be studied properly by any practitioner.

References

1. Dave Muoio. (2018) “Standford Study Finds Vr Imaging Boosts Radiologists Confidence”. MOBI Health News. Accessed on: https://www.mobihealthnews.com/content/stanford-study-finds-vr-imaging-boosts-radiologists-confidence
2. Elsevier. (2015) “First In-man Use of Virtual Reality Imaging in Cardiac Cath Lab to Treat Blocked Coronary Artery”. Elsevier Research and Journals. Accessed on: https://www.elsevier.com/about/press-releases/research-and-journals/first-in-man-use-of-virtual-reality-imaging-in-cardiac-cath-lab-to-treat-blocked-coronary-artery
3. Sanjay G. Asrani (2013) “OCT and Glaucoma: Artifact Alert”. Review of Ophthalmology. Accessed on: https://www.reviewofophthalmology.com/article/oct-and-glaucoma-artifact-alert
4. Mark Draelos, Brenton Keller, Christian Viehland, Oscar M. Carrasco-Zevallos, Anthony Kuo, and Joseph Izatt. (2018) “Real-time visualization and interaction with static and live optical coherence tomography volumes in immersive virtual reality”. OSA Pusblishing, Biomedical Optics Express. Accessed on: https://www.osapublishing.org/boe/abstract.cfm?uri=boe-9-6-2825&origin=search