3D Printed Eye Prostheses Can Help Children with Missing or Underdeveloped Eyes to Grow Normally

Microphthalmia is a condition in which babies are born with severely underdeveloped eyes, while anophthalmia is a condition in which one or both eyes are missing altogether. Both conditions obviously cause blindness, but that’s not the only complication – without a full-sized eye, the eye socket won’t grow and develop normally, causing facial deformity. According to Maayke Kuijten, a postdoctoral fellow at the VU University Medical Center in Amsterdam, if the eye socket doesn’t expand normally, the areas around the eyes can’t expand normally either, affecting the entire face.

Treatment for the condition involves the creation of an ocular prosthesis, or a “glass eye,” though the prostheses are no longer made from glass but medical-grade acrylic. These prostheses can be spherical like a natural eyeball, or cup-shaped to fit over an underdeveloped eye. They’re not easy to create, though, especially for babies. An ocularist typically has to visually gauge the size of the eye socket, create a prosthesis based on guesswork, and then alter it until it fits perfectly.

The process takes time, and a growing baby doesn’t have much of that. Without an eye to support the frame of the eye socket, that part of the skull can actually cave inward, so something needs to be placed there very quickly…something like a 3D printed conformer.

Kuitjen and her research team recently conducted a study in which five infants were fitted with 3D printed eye conformers, which help the eye sockets grow and form as they would naturally. The children were being treated at the office of Dr. Dyonne Hartong, an oculoplastic surgeon at the VU University Medical Center, who is currently treating about 50 patients with microphthalmia or anophthalmia. Using MRI scan data, the researchers assessed the extent of the eye malformation and the size of the eye sockets, and even created molds by injecting a soft gel into the sockets.

Using this data along with data on natural eye development, Kuitjen created an eye growth chart for the next 10 years of the children’s lives. The team then 3D printed several eye conformers, customized to each child based on their scans and in different sizes that matched the predictions of their eye growth. While the conformers don’t look like eyes – they’re just opaque plastic – they’re noninvasive, not painful, and easy enough for parents to insert once they’ve been properly trained. A more cosmetic prosthetic can be designed later in life if desired, but the conformers allow the face to develop with a natural shape.

After about a year of treatment with the conformers, the study has shown that the socket volumes of the children’s eyes have doubled on average. The study is still ongoing.

“This is certainly a novel approach with several advantages,” said Dr. Irene Gottlob, a professor of ophthalmology at the University of Leicester Ulverscroft Eye Unit at the Leicester Royal Infirmary who was not involved in the study. “This is a good example of individualized treatment, or ‘precision medicine.’ It is also a good example of how 3D printing can be used in medicine. However, so far, only five patients have been treated, and we need to see the results of a larger group.”

The researchers plan to improve the mathematical models used to predict the children’s eye growth; Dr. Gottlob said that improvement of ultrasound methods could also help younger infants to receive the treatment. Currently, infants cannot undergo MRI scans before the age of three months because anesthesia is required for them to be still enough for the scans. Because anesthesia is considered too dangerous for infants under three months, ultrasounds are taken instead.

Regardless, Dr. Gottlob calls the method “promising.” While 3D printing can’t restore sight for children born with underdeveloped or missing eyes – yet – it can allow them relief from further suffering caused by their conditions. Discuss in the 3D Printed Eye Confomers forum at 3DPB.com.

[Source: Live Science]