Today’s medical device manufacturing depends heavily on high-precision, non-destructive inspection methods—such as advanced vision systems, coordinate measuring machines (CMMs), and computerized tomography (CT) scanning—to meet strict regulatory standards and ensure quality. These technologies are critical for verifying increasingly complex and miniaturized components.

For several decades, CMM was the longstanding standard to measure parts for first article inspections and other dimensional analyses. In 2015, ISO 80369 issued a dimensional requirement that has resulted in CT becoming more prevalent in recent years, “especially since most medical devices are made of plastics, which can be scanned and analyzed in a non-destructive manner using CT,” said Matt Pasma, program manager for DDL, an Eden Prairie, Minn.-based third-party testing laboratory that performs functional mechanical testing, package testing, and dimensional analysis. “These technologies and software programs have also become much easier and faster to use.” 

“Today, medical device engineers use CT for a wide range of applications in R&D and design, process ramp-up, production, and field support,” stated Lumafield, a Cambridge, Mass.-based provider of non-destructive, high-resolution industrial CT scanning services to the medical device manufacturing industry. “Integrating CT into medical device development gives engineers a more advanced tool to improve design accuracy, validate manufacturing processes, and comply with regulatory requirements to ultimately bring safer and better products to market.”¹

“Other advantages of CT scanning technology are minimizing gage R&R issues that arise from human interaction, physical contact with components, and deceptive lighting issues,” added Brent Hahn, senior vice president of Isometric Micro Molding, a Nissha Medical Technologies company based in New Richmond, Wis., that provides advanced micro molding and automated assembly solutions for the medical device industry. “By comparing millions of data points to the original CAD model and examining the interior of parts for bubbles or air traps, CT scanning provides a robust metrology solution, ensuring that components are manufactured precisely as designed.”

Within the medical device industry, there is a strong push toward automation and artificial intelligence (AI) in inspection. AI improves defect detection, minimizes human error, and accelerates data analysis. “CMMs are becoming more automated for faster, more accurate measurements,” said Lauren Sousa, senior quality technician for MTD Micro Molding, a Charlton, Mass.-based provider of ultra-precision micro molded components for the medical device industry. “With medical devices having more complex internal features, CT scanning has improved the inspection resolution, which allows for better imaging of smaller parts and obtaining more accurate measurements.”

Latest Trends

Inspection systems are becoming more advanced with the use of multiple sensors and other digital tools. “An integrated approach that blends vision, inspection, CMM, and CT—with CT scanning playing an increasingly prominent role in front-end development—is essential to drive reliability, ensure quality, and accelerate speed to market,” said Jarrod Aydelott, director of global tooling and molding for Aptyx, a Tempe, Ariz.-based manufacturer that provides complex molding, extrusion, coating, and assembly services to the medical device industry. “This combination enables a more efficient, data-driven process from the start.”

A shared challenge across the industry is collecting data, validating its reliability, and using it to make confident decisions as quickly as possible. Standard CMM metrology can be a time-consuming process that results in delays. “This bottleneck is a well-known issue in traditional inspection processes, often leading to significant setbacks in development timelines,” said Ray Scherer, global engineering manager for Aptyx.

In contrast, CT scanning enables rapid part inspection and accelerates time to market. Manufacturers that do not adopt this technology—or partner with a company that does—face slower processes. “Many still rely on traditional CMM methods, but the trend shows that without investing in CT scanning and the expertise to use it effectively, the metrology phase takes longer, ultimately delaying time to market,” said Scherer.

More medical device manufacturers (MDMs) and contract manufacturers (CMs) are accepting CT as the best way to non-destructively analyze parts, especially those made from plastic. “Being able to see the full 3D model, and also quickly take measurements off the point cloud, has opened up the doors for getting rapid feedback on any mold adjustments that are needed,” said Pasma. 

What MDMs Want 

MDMs want the latest inspection systems with the highest possible precision and resolution. They especially want speed, without sacrificing quality or accuracy. Non-contact inspection for delicate micro parts is high on their lists, “and they are prioritizing automation to reduce variability and improve throughput,” said Sousa. “There is a growing need to inspect internal geometries and achieve consistent, high-resolution results. These needs are driven by greater complexity, miniaturization, and tighter tolerances.”

MDM requests are less focused on the inspection method/technology and more focused on the outcome, trusting their manufacturing partners to get their products to market in the fastest possible way. “They’re looking for ever-increasing speed to market—lightning speed, you might say,” said Scherer. “We have found that CT scanning plays a critical role in accelerating validations, preventing delays, and ultimately helping us deliver faster, with more reliability.”

Advanced Tools and Technologies

CT scanning continues to increase resolution and process speed, with a smaller overall equipment footprint. Because of increased demand, Isometric recently added a second CT scanner to “build our bandwidth as our company continues to grow,” said Hahn.

Optical CMM systems use cameras and other optical sensors to capture the dimensions and geometry of objects. They are especially well-suited for measuring delicate, thin-walled, or flat workpieces. “These systems are becoming very popular with the advancement of image processing,” said Dan Logan, senior metrologist III for Isometric Micro Molding. “They provide the ability to take extremely accurate 2D and 3D measurements. It is also a non-contact process, which is important for small and delicate parts.”

Laser scanning is becoming a strong competitor to CMM and CT. These laser systems deliver fast, highly detailed, non-contact 3D measurements. For many applications, they are outperforming traditional CMMs or CT, especially when footprint, speed, and versatility matter. Laser scanners offer an extremely high resolution and are compact, which allows them to be mounted directly onto robots. The process can then be fully automated for advanced inspection and “lights out” manufacturing. Some scanners are even handheld, making them suitable for measuring large components.

Unlike standard methods that provide limited data points or graphs, CT scanning brings the part to life, showing the complete geometry in relation to the CAD model and offering a full, intuitive understanding of what is happening. 

“We had a real-life case with a medical device manufacturer where a part had been stalled for two years due to issues flagged by traditional metrology,” said Aydelott. “When we approached the problem using CT scanning, we discovered there was actually no issue at all. The difference was in the level of insight—CT scanning allowed us to visualize the entire shape of the part, revealing features that were not captured dimensionally by CMM.” 

Aptyx scanned the parts and generated heat map overlays by comparing the CT scan data to the CAD model. The initial alignment followed the datum structure defined in the product drawing, which allowed engineers to assess the overall fit. However, the heat maps revealed a misalignment between the scan and the CAD, caused by how the datum structure was defined. “This misalignment led to apparent variation in tooth width measurements across the gear,” said Aydelott. “After restructuring the datums to better reflect functional alignment, we achieved consistent and reliable measurement data.”

Innovation at the Forefront

Measurement technologies keep evolving and improving. Tools that were once mainly used in the medical world, such as CT scanning, are now becoming standard practice across other industries (“industrial CT”). “From metrology to dimensional analysis/first article inspections to reverse engineering to troubleshoot package assemblies, the options for using CT are becoming endless,” said Sousa. “The size and power of machines to handle bigger, more complex parts made from more challenging materials is becoming more of a reality.” 

Innovation is happening quickly in the metrology world, especially in vision and CT. AI-driven vision systems are enabling smarter inline inspections. “CMMs are evolving with better automation and robotic integration,” said Sousa. “CT is also seeing major improvements in software, speed, and resolution.”

CMM/CT scanning is now used to validate new designs and new material performance, tooling optimization, assembly verification, failure analysis, and even supplier qualification. Ensuring suppliers meet quality standards is a key concern in medical device manufacturing. “CT scanning provides an efficient way to assess incoming materials, components, and subassemblies from vendors before they enter the production line,” said Lumafield. “By non-destructively inspecting parts from different suppliers, manufacturers can quickly identify inconsistencies, detect hidden defects, and ensure conformance to design specifications.”¹

Currently, the biggest trend in metrology is combining technologies into hybrid systems (e.g., vision plus CT plus CMM), offering all-in-one inspection capabilities. For example, AI plus CT hybrid systems allow for fully automated internal inspections within minutes. CT systems can auto-identify defects, extract geometric dimensioning and tolerancing (GD&T), and generate validation reports without human intervention. “This turns what used to take hours or days into a 10-minute or less push-button process,” said Sousa. “It allows for non-destructive validation of internal geometries to become more common, even in production.” 

CT manufacturers are working to develop automation for scanning and multi-material scanning, with faster scan times and improved X-ray sources. “New software for CT scan processing—for example, KOTEM’s EVOLVE SmartProfile²—has the ability to understand GD&T and datum features directly attributed from an intelligent CAD model,” said Logan. “This is a benefit to program time and gives confidence to the programmer that the scanned part is properly aligned for accurate GD&T measurements.”

Constant updates to machine software and analysis software not only fix bugs but also make software more user friendly. “Manufacturers of CT machines are adding models that are better suited to the power needs to scan metal and get a perfect scan of those devices,” said Pasma. “This allows more non-destructive methods to be used for various measurement analysis, or even defect analysis, with the ability to penetrate the different harder metals with the X-ray beams.” 

AI can be integrated into nearly all systems and is being used for defect detection, image reconstruction, and part segmentation in CT. For vision systems, this includes advances in lighting and edge detection. AI speeds up inspections, reduces false positives, and brings higher consistency to quality control. In CT scanning, AI can automatically detect part cavitation based on cavity IDs on the molded parts. Pass/fail criteria can also be taught to a system to define overall component defects.

Regulatory Ease

CT is a huge benefit for any validation because it captures the entire part in a non-destructive, fast, and simple process. First articles can almost always be achieved with one piece of equipment. “And we have the scans forever, so we can go back to any part and review and take additional measurements,” said Logan. “We can see clues to the performance of the tool, or how humidity and temperature change the part. We can review previous lots and look for trends.”

MDMs and their metrology teams realize that CMM and CT systems are increasingly critical for meeting FDA and ISO validation and traceability standards. CT is especially valuable for inspecting internal features of complex parts in a non-destructive way. “These tools do not just support compliance, they simplify validation, support risk management, and provide data-driven confidence for audits and quality systems,” said Sousa.

A constant challenge for MDMs is proving the precision of the measurements that define their devices. CT allows manufacturers to be more accurate, precise, and confident with their measurements, which can build trust with regulators. “The speed at which these parts can be scanned to show regulatory compliance has greatly increased with CT,” said Pasma. “Even with the additional speed, we still maintain our precision, giving our customers the highest confidence that their parts are in compliance with regulatory specifications.”

Legacy Thinking

Some beliefs held by medical device engineers and/or management about what vision systems, CMMs, and CT can or cannot do may be based on past limitations that no longer apply. For example, a common misconception held by MDMs is that CT is too slow to be used in production. “Older systems used to require hours to scan parts, but newer systems can do full scans in minutes, and sometimes even less time,” said Sousa. “CT isn’t just for R&D or failure analysis anymore; it is used as a routine inspection process.”

Another misconception is that CMMs are only good for larger, flat parts with simple geometries. CMMs can now measure tiny, complex, or freeform shapes with the help of new probe technologies (e.g., optical, scanning, and micro-touch probes) that can handle delicate and complex parts. Yet another erroneous belief is that only one system may be used, whereas hybrid systems can provide multiple technologies to derive the most accurate resolution and measurement. 

“Some people also believe that these systems are too complex or require a metrology expert, when just the opposite is true,” said Sousa. “Modern systems are built for ease of use and automation. For example, pre-programmed inspection templates are available for use, which means that less-experienced users can run highly accurate scans.”

Accurate measuring of additive manufacturing (AM)-made products can be complicated by the many processing variables involved. These can alter structural features, such as porosity and surface roughness, or introduce defects such as inclusions and cracks into the material. Traditional methods for testing the quality and accuracy of AM-made components are mechanical testing and density measurements; however, neither of these can see into the part to identify flaws like CT can. Also, “by combining CT scanning with the ability to produce a single build plate of AM parts containing a matrix of processing parameters, process engineers can develop AM process parameters in a matter of days,” stated rms Company, a Cretex Medical company in Minneapolis, Minn., that provides contract manufacturing services to medical device companies, including machining and assembly.³

In the Near Future

As metrology evolves, automated and AI-based scanning technologies will continue to drive innovation that enhances efficiency, accuracy, and adaptability. However, metrology is not just about new tools and technologies—it is also about better integration with design, production, quality systems, and even patient data. “Staying current with these advancements will better position MDMs for speed, compliance, and innovation,” said Sousa.

For example, AI can be programmed to identify flash and contamination. “When CT scanning evolves to the point where it scans dissimilar materials, we can very accurately measure the individual components within an assembly,” said Logan. “Think how meaningful that would be on a defibrillator or pacemaker, or a neuro implantable device.”

“The acceptance of CT in the medical device world is also advancing the competition,” said Pasma. “Having one machine do what used to take two or three machines to do, along with being able to create 3D models that we now can compare to a CAD file and get a comparison heat map to show where defects might be, or where a mold might be having issues, is game-changing. The possibilities are starting to become endless on how to use CT to advance medical device manufacturing.” 

The precision and speed at which these machines can measure different parts is astonishing. For example, CT scanning has the resolution to clearly see details in features that are three to five microns in diameter. Laser scanning can capture nearly 5 million measurement points per second, greatly improving accuracy and speed. Lumafield’s Ultra-Fast CT technology, launched last year, can capture high-resolution internal scans of medical devices in as little as 0.1 seconds.⁴ This technology can speed up CT inspection by more than 100 times, making it practical for high-volume manufacturing.

CT resolution increases every year and can incorporate automation for unattended scanning. On the horizon is the ability to CT-scan even faster, by scanning specific areas of a component for high resolution, instead of the entire part. “Another significant feature is the use of dynamic power settings where the machine changes power levels based on density of the specimen,” said Logan. “This allows us to scan parts that have multiple materials more accurately.”

“With this kind of precision and speed, “being confident in parts with features that are hard to see with the naked eye, or at times, require sub-micron measurement abilities, really shows how far the technology has come,” said Pasma. “I believe the medical device industry will continue to push what can be done with CT and CMM and that CT will eventually overtake CMM as the preferred method with the continued advancements in that technology, if it has not already.”

References

1. tinyurl.com/mpo250751 
2. tinyurl.com/mpo250752
3. tinyurl.com/mpo250753
4. tinyurl.com/mpo250754

Mark Crawford is a full-time freelance business and marketing/communications writer based in Corrales, N.M. His clients range from startups to global manufacturing leaders. He has written for MPO and ODT magazines for more than 15 years and is the author of five books.