Resources

BoneMRI: a solution towards safer spine surgery workflows

BoneMRI: a solution towards safer spine surgery workflows

By: Eva Kleinveld

Modern healthcare is constantly evolving with innovations that enhance patient care and prioritize safety. Imagine a world where image-based navigated surgical procedures can be performed with high accuracy, while lowering or even eliminating the risks associated with harmful ionizing radiation exposure. In this blog post we explore the evolving world of spinal surgical planning and navigation with the capability of adding BoneMRI into this surgical workflow to safeguard patients and clinical staff from hazardous radiation effects.

Imaging for surgery

Last decades, there has been an upward trend in the number of spinal surgeries executed worldwide, due to factors including:

  • The aging population 1,2
  • A broader range of indications2
  • The development of enabling  technologies in diagnostics and surgical procedures2,3

The complexity of the spinal anatomy and neurovascular structures involved has been challenging for surgical procedures. Throughout the years, optimized innovations for better accuracy and safety have been developed in spinal surgery. One of these innovations relates to the equipment for surgical planning and navigation4.

The planning stage involves a preoperative or intraoperative CT scan that provides the surgeon with a detailed understanding of the patient’s anatomy in 3D. The surgeon can use this information to define the treatment plan, including definition of the optimal screw trajectory, assessment of the 3D morphology as well as for sagittal alignment5. Moreover, the imaging and planning could be utilized to navigate during the procedure. In case preoperative CTs are being used for navigation, 3D-2D image fusion is often required to register the patients’ anatomy in the operating room with the preoperative plan. This fusion process requires intraoperative 2D fluoro shots.

 Radiation exposure

  1. During the workflow of navigated spinal surgeries, there are different moments where patients could be exposed to ionizing radiation:
  2. Preoperative CT scan, to plan and prepare for surgery
    Intraoperative 2D fluoroscopy, to register preoperative plans to the real-time anatomy
  3. Intraoperative 3D use of an O- or C-arm, or CT, to provide reconstructions real-time, potentially used for planning and navigation.

Although innovations have greatly improved surgical planning and navigation, concerns arise about preoperative and intraoperative radiation exposure and its risk for developing malignancies. Following the FDA, the risk for fatal cancer is estimated to increase with 1 in 2,000 people as a result of a typical CT with an effective dose of 10 mSv*6. Ionizing radiation is even more relevant in pediatric patients, as this population is more vulnerable to the consequences of radiation exposure7. This has been highlighted recently by Striano et al., projecting that 1 in 1000 adolescent idiopathic scoliosis patients undergoing navigated surgery, with a median radiation exposure of 8 mSv, will develop malignancies8.

Besides the clinical impact of radiation on patients, clinical staff are exposed to scattered doses of radiation during intraoperative imaging, a large concern as well9, 10. As dose is cumulative, when performing large numbers of surgeries, the staff needs to be aware of their annual dose limits. One of the risks seen in orthopedic surgeons using image-guided navigation is an increased chance of developing thyroid malignancies11. Furthermore, Chou et al. showed that the prevalence of developing breast cancer is almost 4-fold higher in female orthopedic surgeons utilizing intraoperative imaging compared with matched women12.

*A spine CT exam has an approximate average effective dose of 6 mSv13.

 

BoneMRI to prevent radiation exposure

From left to right: soft tissue, BoneMRI and CT

While navigated spinal surgery is annually increasing worldwide, there is a need to strive for methods that can reduce radiation exposure for both the patient and the physician. BoneMRI, an MRI-based imaging solution that offers 3D visualization of osseous structures for accurate geometric and quantitative assessment, enables radiation-free preoperative imaging and as such it eliminates the necessity of a preoperative CT.

The availability of a preoperative 3D image could obviate the need for intraoperative 3D imaging for planning and navigation. Therefore a preoperatively obtained BoneMRI can facilitate radiation reduction before and during the surgery, which is a great advantage for patients. In addition, the reduction of ionizing radiation during intraoperative imaging procedures throughout a surgeon’s lifetime obviously reduces health risks2.

First successful human spine surgeries based on BoneMRI

After testing the application of BoneMRI in surgical settings in simulation studies as well as cadaver studies, Spine Surgeon Dr. Poelstra from Southern Hills Hospital in Las Vegas, USA, was the first to successfully use BoneMRI for planning of fusion surgery, meaning that 3D-2D image fusion and screw trajectory planning were based on BoneMRI.

After several simulated planning with BoneMRI side by side with traditional CT scans, I was able to determine that the accuracy and image quality was very comparable.

Dr. Kornelis Poelstra

Robotic Spine Surgeon, Southern Hills Hospital in Las Vegas, USA

I can now provide my patients a one-hundred percent radiation-free experience from their pre-op exam through the navigation imaging for their spine surgery.

Dr. Jacob Rumley

Orthopedic Spine Surgeon, Center for Spine and Orthopedics in Denver, USA

Additionally, Dr. Rumley from the Center for Spine and Orthopedics in Denver, USA, demonstrated BoneMRI’s utility in fusion procedures. BoneMRI, coupled with visible light-based navigation, facilitated surgical planning and navigation while offering a completely radiation-free experience for both patients and clinical staff.

BoneMRI should be considered a viable tool in the preoperative assessment of children with hip disorders that could replace conventional CT.

Researchers from Boston Children’s Hospital

BoneMRI is changing the landscape of surgical planning and navigation by reducing or even eliminating the use of radiation within the workflow. Specific patient cohorts, such as pediatric patients suspected of common conditions in the pelvis and spine such as hip dysplasia or scoliosis, may substantially benefit from BoneMRI.

Additionally, BoneMRI can be seamlessly integrated into the clinical workflow, it offers bone and soft tissue information with only one imaging exam, and time can be saved by using the operating room more efficiently. The future can be safer, smarter, and more efficient thanks to technologies like BoneMRI.