When it comes to critical, life-saving care for animals, veterinarians rely on accurate, timely blood analysis to help them make treatment decisions. Thanks to new developments in medical equipment and software, physicians no longer have to wait three to five days for lab results. Now, specially designed compact laser flow cytometers (blood analyzers) can conveniently sit on a countertop in the veterinarian’s office and analyze blood samples in less than 15 minutes. This technology breakthrough is quickly becoming the new standard for providing on-site, real-time feedback to pet owners and their veterinarians — and is increasingly being used for human blood analysis.

The Challenge: Uncovering the Failure

In the spring of 2008, a medical device manufacturer discovered that a large supply of its laser flow cytometers had multiple failures that could not be specifically identified by the company’s internal design team. With thousands of unusable units sitting on the shelf, the manufacturer was faced with the tough decision of scrapping the units and starting over, or determining whether they could be appropriately refurbished at a favorable cost.

Several of the devices were brought to LightWorks Optics (Tustin, CA) for analysis. This provided a unique opportunity for the company’s optical design engineers to analyze and test the device in order to identify the root cause of existing failures, and ultimately, to make recommendations for design updates that would virtually eliminate any future end-use performance failures. Equally challenging would be whether the redesigned device could be produced to meet the manufacturer’s stringent production throughput, acceptance, and budget parameters.

The Solution: Turning Lemons into Lemonade

Over the next few weeks, design engineers applied advanced “reverse-engineering” techniques to identify the underlying cause of multiple failures in the existing devices, which included a lack of manufacturing controls (tolerances and processes), thermally related instabilities in adhesives, mismatched materials, and poor optical alignments. As can be seen in the table, each symptom was methodically diagnosed, the root cause determined, and a design correction identified to ensure that a performance failure would not reoccur.

The new design corrections allowed the machine to accurately focus, count, and measure the blood cells being analyzed with the assurance of long-term alignment stability, regardless of temperature variables.

By fall of 2008, the prototype verification and validation process was completed and the redesigned units were transferred from the design engineering operation in Tustin, CA, to the new High-Volume Production (HVP) facility located approximately 60 miles south, in Vista. The manufacturer had stipulated that 50 quality-tested devices be produced each week — leaving very little room for error. The HVP management team set up a dedicated assembly and testing line utilizing LEAN manufacturing techniques to help save on production costs, reduce potential failures, and ensure predictable throughput. Further cost savings were achieved by hiring qualified technicians at a lower hourly rate, who then underwent intensive hands-on training by the product engineering team.

Within six weeks of production setup, 10 units per day were being successfully produced, with target costs achieved in the first two months of production and throughout 2009. As a result of well-coordinated design engineering and advanced high-volume production teamwork, the medical device manufacturer clearly understood what the device failures were, and received a 90% acceptance rate on the refurbished devices at about one-

third of the original cost.

This article was written by Kent Weed, VP of Engineering for LightWorks Optics, Tustin, CA. For more information, please call 714-247-7175, or visit http://info.hotims.com/34459-163.


Medical Design Briefs Magazine

This article first appeared in the October, 2011 issue of Medical Design Briefs Magazine.

Read more articles from this issue here.

Read more articles from the archives here.