Understanding Vertigo by 3D Printing the Inner Ear

Vertigo is a truly awful condition in which a person feels as though his or her surroundings are moving or spinning. It can be nauseating and debilitating, and there are a number of different possible causes for the condition, though one of the most common is a problem with the inner ear. Inner ear disruption is what causes benign paroxysmal positional vertigo, or BPPV, which is the most common type of vertigo and involves brief, intense episodes of vertigo that last a few minutes and are often triggered by movement.

The inner ear is a complex and intricate area, and it can be difficult to understand the nature of problems that happen inside it. Most cases of BPPV are caused when tiny particles called otoconia break loose from the utricle, responsible for detecting linear movements, and fall into the semicircular inner ear canals. These canals sense the position of our head and help us to orient ourselves in space, and when the otoconia fall into them, the tiny crystals move when the head moves, disrupting our sense of balance.

It’s difficult to understand such a condition without some sort of visual representation, so an organization called Vestibular Today has developed a 3D printed model of the inner ear that doctors can use to help patients understand what’s going on in there, and how it can be fixed. Inner ear models have been used by doctors for that purpose for a long time, but this one is a bit different in that it was created from an actual MRI scan of an inner ear. The resulting 3D print is an exact replica of the inner ear structure, showing the correct angle of the canals in relation to each other and the utricle.

The 3D model was created by the NIH 3D Print Exchange Program, which was launched in 2014, and was then refined, scaled, and 3D printed by 3D Brooklyn.

“We’re used to creating functional product prototypes for clients, but working with a scan of an organ was a nice shakeup. It was the perfect combination for 3D scanning and 3D printing technologies,” said Will Haude, Chief Creative Officer at 3D Brooklyn. “As well as a great visual aid for something that would otherwise have to be imagined. The end result is a functional and educational medical device to help guide patients through necessary motions needed to relieve vertigo. CAD programs aren’t the right tool for this project. For a realistic model with accurate proportions, 3D scanning along with some 3D modeling programs allowed us to clean up the model and add specific features to help call out certain sections of the organ.”

BPPV can be treated through what is called canalith repositioning, which involves a series of head movements designed to move the otoconia back towards the utricle. Doctors can use the 3D printed model to demonstrate the movements to patients, and show them exactly how they will work to affect the inner ear and restore balance by moving the otoconia, represented by rings on the 3D printed model.

“3D printing’s biggest impact could be the medical industry because the platform allows for a wide range of personalized applications,” Daniel Figur, Chief Marketing Officer for 3D Brooklyn, told 3DPrint.com.
“The combination of 3D scanning and 3D printing technologies help create physical models that are perfect for clinician and patient education. When those designs go open source, it allows for anyone to create and apply that model instantly. That 3D file can then be further modified to enhance the overall educational experience. This is a great application for 3D printing because it shows how open-source models can be applied to benefit individuals anywhere in the world.”

Clinicians can purchase a 3D printed inner ear model for $70, or a larger plastic model for classroom applications for $45. Below, you can see how a clinician uses the model to illustrate how canalith repositioning works: