Imagine your brain surgeon has never practiced on a tumor like yours before. In neurosurgery, a surgeon's only chance to experience a specific complex tumor has always been during the actual operation: a single, unrepeatable moment. Now a Japanese university-industry collaboration is changing that, with a 3D model that lets surgeons practice on your exact tumor again and again.

The Surgeon's Dilemma: No Practice Allowed

Surgeons, like athletes, need practice. But in neurosurgery, there has been a fundamental problem that has persisted for decades: you simply cannot rehearse on the real thing.

Every brain tumor is unique. Its shape, size, location, and relationship with surrounding nerves and blood vessels differ from patient to patient. Yet traditionally, a neurosurgeon's only opportunity to navigate a specific tumor's complexity was during the actual surgery itself. For the patient on the operating table, it was always the surgeon's first and last attempt at that particular case.

Surgeons can study CT and MRI scans beforehand, of course. But the information gleaned from a flat screen is fundamentally different from the three-dimensional tactile reality of tissue, bone, and surgical instruments. Textbooks and monitors simply cannot convey the spatial relationships between a tumor and the delicate structures surrounding it.

Enter the "Hakata Model"

In February 2025, Kyushu University's Graduate School of Medical Sciences and Japan Medical Company announced the launch of a joint research project to tackle this problem head-on. Their creation is called the "Hakata Model," a next-generation medical training platform named after the historic district of Fukuoka, the city where Kyushu University is located.

The Hakata Model's core innovation lies in its ability to reproduce a specific patient's intracranial anatomy, including their unique tumor, with extremely high precision based on CT/MRI data. This is not a generic skull model. It faithfully recreates the tumor's shape, extent, and its spatial relationship with surrounding nerves and blood vessels for each individual case: a truly "patient-specific" training tool.

The joint research involves Professor Koji Yoshimoto and Lecturer Taisuke Kuga from the Department of Neurosurgery at Kyushu University's Graduate School of Medical Sciences. The project builds on the KEZLEX precision medical model technology that Japan Medical Company has refined over approximately 25 years.

KEZLEX: 25 Years of Building Models You Can Actually Drill

The foundation of the Hakata Model is KEZLEX, a precision medical replica model that reproduces the internal and external structure of human bones from 3D CT/MRI data. Its defining feature is that it can actually be drilled: it replicates the tactile sensation of cutting into real bone, and even the feel of applying surgical clips.

Japan Medical Company's predecessor, Ohno Kogyo, was founded in 1897 as a steel trading company. In 1999, the company began researching 3D printing technology for medical applications and succeeded in reproducing the stapes, the smallest bone in the human body. This technology has been patented internationally and is now used in over 50 countries, including the United States, Europe, China, and Southeast Asia.

Until now, KEZLEX has primarily been used to reproduce anatomical structures. The Hakata Model adds a crucial new element: the individual tumor itself. Integrating anatomical models with tumor models has the potential to fundamentally transform the concept of surgical training.

From "Once Only" to "As Many Times as Needed"

The essential transformation the Hakata Model brings is converting a "one-time surgical experience" into "shareable, repeatable training." Several applications are envisioned.

First, repetitive skill practice. Surgeons can grasp the three-dimensional spatial relationship between the tumor and surrounding nerves and blood vessels before surgery, then practice the required techniques as many times as needed. The specific hand movements that previously existed only in a veteran surgeon's muscle memory can now be experienced by junior doctors.

Second, location-independent training. Because the model is physical and portable, training is not limited to the operating room. The same model can be shipped to regional hospitals or overseas institutions, potentially narrowing the educational gap between urban medical centers and rural facilities.

Third, enhanced team-based medicine. Specialists in microscopic surgery, endoscopic surgery, and exoscopic surgery can gather around the same model to discuss and compare different approaches. This enables teams to collaboratively develop optimal surgical strategies that minimize complication risks.

Professor Yoshimoto noted that the model allows surgeons to visualize tumor shapes and nerve-vessel relationships unique to individual cases, enabling risk prediction. This underscores the Hakata Model's role not just as a training tool but as a surgical planning aid.

3D-Printed Surgical Models: A Global Movement

The application of 3D printing to surgical training is accelerating worldwide. Since the first skull model was created from CT images in 1990, the 2010s saw costs drop to practical levels, with research advancing in spinal surgery, vascular surgery, and brain tumor surgery.

However, current 3D-printed models share a common limitation: haptic realism remains insufficient. While bone texture can be replicated, the elasticity of brain tissue and the softness of tumors are not yet fully reproducible. Typical 3D-printed surgical models cost between $100 and $1,000, though real costs including labor are substantially higher.

What sets the Hakata Model apart is the level of tactile fidelity achieved through 25-plus years of KEZLEX refinement. Rather than simply reproducing shapes, the focus on replicating the feel that a surgeon's hands experience reflects a distinctly Japanese monozukuri (craftsman-like manufacturing) philosophy. This meticulous approach to manufacturing could set a new benchmark in the field.

Patient Safety and the Future of Medicine

The Hakata Model's development ultimately serves patient safety. When surgeons can adequately practice before an operation, their ability to handle unexpected situations improves and complication risks decrease.

Furthermore, the ability to accumulate and share valuable surgical cases as "educational assets" will accelerate the transfer of expertise. Knowledge and experience that once lived exclusively in a veteran surgeon's hands can now be accessed by the next generation of doctors.

Kyushu University and Japan Medical Company have set their sights on establishing the Hakata Model as an internationally standardized education and evaluation platform originating from Japan. How the fusion of Japanese precision manufacturing and medical research will reshape neurosurgical education worldwide remains a story worth following.

How are surgeons trained in your country? What do you think about using 3D-printed models to practice brain surgery? We'd love to hear your perspective.

References