MMC Magazine

(Arakawa Ward, Tokyo)

Blade thickness at the edge is only 0.08 mm.
Scissors used deep into the brain.
Leveraging technical skill to help doctors save lives.

Called an artist for his machining technique

When we entered the 1st floor of a building that looked like an ordinary house in Arakawa Ward, Tokyo, a small machining centre S191 from BUMOTEC (Switzerland) caught my eye. CEO Takashi Takayama had traveled to Switzerland to purchase this high-performance machine. He related what the BUMOTEC President said to him after the sale had been completed. He was surprised that a company with fewer than 10 employees wanted to purchase this machine. When he saw how effectively Takayama had employed the S191 to manufacture products, however, he called him an artist.

“BUMOTEC now tells Japanese companies considering purchasing their machining centres to consult with me first. It looks like I’m working as a volunteer consultant for BUMOTEC,” said Takayama with a laugh".

A small-size machining centre S191 made by BUMOTEC operated at the Arakawa Factory / Ryushi Takayama, CEO, Takayama Instrument, Inc.

Another factory has three of these machining centres. “These are the TRAUB, Swiss-type CNC automatic lathe TNL series, manufactured by INDEX in Germany. There are only three in Asia, all at our factory.”

Takayama Instrument employs these machines from overseas to manufacture scissors and tweezers used in neuro bypass procedures. Domestic market share for the scissors has reached approximately 90%, which means that most of the neurosurgeons in Japan are using them. One Takayama Instrument product is called the Kamiyama Microscissors Muramasa Special. These micro scissors were custom developed for Hiroyasu Kamiyama, a neurosurgeon at Sapporo Teishinkai Hospital.

They have become the global standard for scissors used in neurosurgery. The thickness of the edge is only 0.08 mm, extremely thin, but very sharp. With a sales force active in 30 countries, overseas sales have grown to account for approximately 30% of the company’s turnover in the two years since they were introduced to the market.

“I’m spending about 100 days a year outside Japan for business. As the number of exporting partners increases, the need to adjust to conform to regulations in different countries has increased. Satisfying the requirements for all production processes has been a challenge, but it’s well worth the effort to achieve customer satisfaction,” said CEO Takayama.

Muramasa Special custom-made for a physician

Since its foundation in 1905, Takayama Instrument has manufactured scissors, scalpels and other tools for medical use. Until they mechanised, however, everything was made by hand. “We didn’t have drawings, just old samples that our craftsmen used for comparison. It was like we were starting from scratch each time. I knew we had to mechanise to ensure stable quality for mass production.” However, with little know-how in machining and no machine tools, Takayama hit the books to learn. He read up on material engineering and machining. He implemented and adjusted machines and designed tools by himself to develop effective methods and techniques.

Meanwhile, CEO Takayama met Yasuhiro Kamiyama, a surgeon well known for his outstanding skill. Dr. Kamiyama also developed surgical instruments in the hope of advancing the state of neurosurgery. One of these is the Kamiyama Microscissors Muramasa Special.

To cut out small lesions located deep in the brain, the blade edge needs to be as thin as possible. However, the extremely thin edges prevented the two blades from aligning smoothly, and this resulted in a loss of performance. Dr. Kamiyama then considered adopting blades that were bent like a curved lance to add rigidity. Takayama took this idea and succeeded in producing micro scissors that now provide a sharp cut.

Since then, CEO Takayama has been engaged in product development based on requests from Dr. Kamiyama. Takayama also asked Dr. Kamiyama for permission to watch surgeries so he could observe the movements of the surgeon’s hand during procedures. Reading many books on neurosurgery and observing the actual movement of the surgeon allowed him to deepen his understanding and pick up many ideas for new product development.

Masaki Nakamura, Chief at the Arakawa Factory, Takayama Instrument, Inc. / TRAUB made by INDEX in Germany Swiss-type CNC automatic lathe, TNL series

Designing tools to reduce the load on the surgeons

While observing surgeries, CEO Takayama noticed something important. Neurosurgical procedures last at least two hours. The core is only about 20 minutes, during which the lesion is removed, but the neurosurgeon has to maintain a high degree of concentration throughout the procedure.

“Even when tired, the surgeon cannot relax for an instant. I wondered what I could do to reduce the load on the surgeon. After watching many surgeries, I understood how the surgical field looks and how much space they have in the operating room. I decided to develop easy-to-use tools focusing, on cutting and suturing.”

This led to the development of tweezers with tungsten tips. Suturing requires tweezers and microneedles. However, the material was stainless, which was slippery. It takes eight stitches to suture a blood vessel measuring 1mm in diameter, and few surgeons are skilled enough to do this easily.

Takayama worked with Dr. Rokuya Tanigawa, who trained under Dr. Kamiyama, to develop better tools. One of these was tweezers with tungsten tips that would not slip. “Having tweezers with non-slip tips has reduced suturing time from 20 to 15 minutes, and it has completely changed the technique that surgeons use. About 600 units were sold in Japan during the first year alone.”

Takayama told us that the idea of adding something to the edge to prevent slipping was not new; and when they asked a contractor to have tungsten added to the tips, they could not handle it easily. Then they figured out how to maintain tungsten in the condition of plasma, ionized, then let the tungsten infiltrate the edge of the suturing tool.”

It is actually a simple idea, but it was built upon the foundation of an extensive knowledge of metals. How does he continue to have such innovative ideas? Takayama says, “I’m always looking for ways to make surgery safer.”

Accuracy and safety that saves lives

Takayama Instrument tools are highly regarded by surgeons because they shorten the time required for procedures. The instruments cut well and grasp securely. Improvements in the quality of endoscopes and other optical equipment enable more delicate procedures, but such surgeries require the highest quality instruments.

To ensure such quality, CEO Takayama employs expensive, highly functional and rigid European machining centres. The BUMOTEC machines allow all processes, from cutting to milling, to be completely automated. However, it took time to come this far.

“First, we created drawings from the samples we had. Next, I used the drawings to design programs for the machines. I observed the machine movements and designed programs for all the patterns that I could think of. In the end, I had about 100 programs. When I ran the programs, though, the tools collided so I asked the manufacturer to make adjustments. The excellent working relationship we have with BUMOTEC allowed us to achieve the modifications we required to the point that our machines are almost completely customised.”

They worked tirelessly to modify the machines and increase performance through a wide range of improvements. It was hard to achieve accuracy in continuous operation because materials like titanium alloys are hard to cut, and this caused workpieces to slip in the chucks. To correct this, they designed different programs for different parts, used special tools and developed special lubricants.

Takayama Instrument has developed a wide range of manufacturing methods in-house, acquired ISO13485 certification and passed inspection by the United States Food and Drug Administration (FDA).

“ISO13485 requirements are very complex, and compliance was a major challenge with the in-house processes we had in place. To identify better approaches to the requirements, we consulted with an expert. This allowed us to satisfy the requirements in a way that was more compatible with our established systems. As a result, we customised processes to satisfy all the requirements and passed final inspection.

However, when customising processes, production quality is not the only concern. A current project being carried out in collaboration with companies in the medical and engineering industries, CEO Takayama placed the highest priority on safety. This is a very detailed and painstaking process. For example, Takayama considers the potential for risk if part of an instrument can’t be sterilized completely, or corrosion caused by combining different materials.

“What if an instrument breaks during a procedure? What if a surgeon drops a screw because it is slippery? You can never overdo risk management, and we fully leverage the know-how we have accumulated over our 100-year history to ensure the highest degree of safety. Importantly, because our products have a great impact on lives, we never stop thinking about safety.”

Newly developed suction device with an irrigation function. A uniquely developed surgical tool, requested by Dr. Kamiyama.
It took five years to develop this all titanium tool for both suction and irrigation. Already patented internationally.

Improvements that ensure the highest degree of efficiency and precision

CEO Takayama says that there is always room for improvement in cutting tool manufacturing. “Takayama Instrument’s strength in manufacturing is built upon a firm foundation of craftsmanship, and we have continued to improve upon this strength to supply the highest quality in value-added products through automated machining. We handle hard-to-cut titanium alloys, and accept the challenge of processing special parts that require us to implement unique procedures. In some cases, using an end mill for plastics produces better results than when processing titanium alloys, a material that is difficult to grip with chucks. Implantation is required to be a minimally invasive procedure; therefore, all edges need to have a round honing. In such machining, tools have to cut accurately even at high speed. Considering such a wide range of conditions, we want suggestions and advice from cutting tool manufacturers on the best conditions and how to maximize their capability.”

Factory Chief Masaki Nakamura said, “Mitsubishi Materials promotes product development for medical use and tool development for automatic lathes. I am especially interested in products and know-how for hard-to-cut materials. The Smart Miracle End mill Series for hard-to-cut materials and mirror finished turning inserts for titanium alloys are very close to our needs. We’d like to test them.”

CEO Takayama told us what he expects from Mitsubishi Materials: “Although I have plenty of ideas, and because we design instruments for specific needs, tool manufacturers may not see a major benefit in developing tools for our smaller-scale production. I feel strongly that collaborative relationships between machine and cutting tool manufacturers will become increasingly important. Mitsubishi Materials is impressive in the area of product development, and we are looking for help in enhancing the quality of our products with Mitsubishi Materials’ know-how and technology as cutting tool professionals.”

Our vision has not changed. We continue to develop instruments that enable surgeons to operate safely and comfortably. If we can safely reduce the time required for procedures, patients will benefit. We maintain this spirit in product development and improvement of manufacturing processes. Products based on this spirit save lives around the world.