Positioning of bio model and registration.
View of Incision and burr hole.
Alignment of biopsy arm.
View of bio model with biopsy arm and biopsy needle in place.
Flesh and bone
The Centre for Biomedical and Technology Integration (CBMTI), a commercial spinoff of the
University of Malaya in Malaysia, creates custom medical implants for government and private
hospitals. It also works closely with the healthcare industry to enhance hospital management
and surgeon training. 3D printing is vital to both sides of the business. The company uses
3D printed masters in a cold pressing technique to shape its titanium implants. And in a
groundbreaking training program, it develops detailed multi-material 3D printed models that
mimic the appearance and textures of real body parts, even down to a specific patient’s tumor.
At the company’s inception, computer simulations and cadavers were the only way to train
professionals on neurosurgery equipment. CBMTI felt 3D bio models could greatly enhance
training, and became interested in 3D printing as a way to build quality models quickly. The
organization’s first 3D printer made spatially accurate models, but only in one, solid material.
To closely mimic human pathology, CBMTI added simulated soft tissue in a labor-intensive
secondary process that could take as long as a week. This post-processing proved slow and
costly, both financially and in terms of staff hours.
As 3D printing technology evolved, CBMTI knew multi-material 3D printing would create
lifelike models more efficiently and cost-effectively. Two Stratasys® systems stood out: the
Objet Eden 350TM 3D Printer, which can build a model in any one of 17 distinct materials, and
the Objet500 ConnexTM 3D Printer, which offers more than 100 materials and can combine
disparate materials in a single model.
CBMTI invested in both 3D printers. "Stratasys printers were shortlisted as they are able
to print multiple materials. They were chosen because of their accuracy and the speed at
which they can print. Ease of use was another reason," said Yuwaraj Kumar Balakrishnan,
CBMTI operations manager.
Better Models, and More of Them
Today, the company has increased production capacity by 40 percent with Stratasys 3D
Printers. It uses its Eden 3D Printer for surgical planning, focusing on devices used during
surgery, such as jigs and guides. The Connex 3D Printer creates prototypes for university
research projects and manufactures biomodels. With the capability to 3D print multiple
materials simultaneously, CBMTI now fabricates models that feature different textures and
densities over their surfaces and throughout their interiors, just as human body parts do.
The process starts by converting patient data from CT and MRI scans into imaging data,
then assigning material characteristics to each portion. The 3D printer uses this data to
build physical models that are accurate spatially and anatomically. Typically, two base
resins combine in various proportions to render a spectrum of properties — for example,
hard and very soft with many variations in between.
"With the Connex, we simulate realistic layers of human tissue like skin, bone, dura, brain
and tumors within the printed model. The model is then used in surgical simulations. We
have also incorporated other features such as fluid dynamics so that we can simulate
endoscopic neurosurgical procedures as closely as possible," Yuwaraj Kumar Balakrishnan
explained. Fluid dynamics include adding tubes with liquid at various pressures to
In addition to lifelike realism, the process of fabricating end-use products directly
from imaging data (called digital manufacturing) lets the company easily create
scaled-down versions of its models for quick testing and to conserve material when full
size is unnecessary.
Interest has significantly increased since CBMTI invested in 3D printing. A team of 20
medical clinicians, rapid-prototyping engineers, computer programmers and electrical
engineers work together on three main 3D printing-based lines of business: creating
prototypes for university research; developing custom titanium implants; and manufacturing
custom biomodels for surgical training. "Researchers’ interest in our models has increased
a hundredfold since we began using these printers," Yuwaraj Kumar Balakrishnan said.
"Stratasys printers are the ideal platform for innovation. We have gone from being only able
to mold titanium plates for cranial implants to being able to create biomodels with pathology
from actual patient imaging data," he said.