CASE STUDY

TearScience Activator


Client: TearScience, Acquired by J&J in 2017

Project: Activator

Understanding the Problem

Meibomian Gland Dysfunction (MGD) is the leading cause of dry eye world-wide, and most recommended treatments, such as eye drops and warm compresses only treat the symptoms to provide temporary relief. Through years of research, renowned Boston Optometrist Dr. Donald Korb found that MGD could be treated by applying directed pressure to the eyelid which evacuates the meibomian glands of hardened oils. This was a painful procedure, but patients with severe cases of dry eye would do anything to find relief. TearScience was created to find a pain-free, simple treatment solution to this worldwide and debilitating problem.

01


Prototypes, Experiments, and Iterations

Discovering an effective treatment method was all about learning what was user-friendly, patient-friendly, and effective. Through prototype and testing iterations, we discovered the formula that was most effective: heat and directional pressure. We continued our research iterations, figured out safe ways to deliver energy and honed in on the most effective delivery methods, which separated the TearScience technology from all others.

We used a green dental impression molding compound to get the forces on the eyelids correct.

We experimented with several types of devices, measuring thermal properties, forces on the eyelids, and pain tolerance.

02


Inventing Technology

Once we figured out the formula of heat and pressure that was effective, we worked to optimize the technology, and this is where the real breakthrough occurred. We realized that the most effective measure to treat MGD was heating from inside the eyelid. So we invented technology that we could shape, control, and safely operate within the shape of a thick contact lens.

03


Ease of Use

We spent considerable effort investigating the usability of the device. Not only did the device have to be easy for a doctor to install, but it was also important that it could be installed correctly to provide an optimal treatment. We designed several prototype iterations for usability studies to consider these factors:

  • Understanding the visibility of the procedure for the physician
  • Ensuring the device worked with different eye shapes, sizes and eyelid elasticities
  • Determining how the placement of the Activator affected treatment effectiveness

04


Regulatory Approval

Our engineering and regulatory team successfully designed the testing protocols and regulatory pathway to get the TearScience devices through the FDA process. For the activator, this involved proving that the device was not excessively heating the cornea through porcine eye testing. These tests proved that the forces transmitted by the bladder were safe through empirical force testing and virtual finite element models, as well as proving that the materials used were biocompatible even if the device was compromised in the eye. The design controls we developed and used successfully in these FDA audits are the basis for the Blur design control system we use today.

Test and Assembly Fixtures protocols for regulatory approval
Bladder analysis and testing protocols

05


Design for Manufacturing

The electro-mechanical design of the Activator was always developed in coordination with its eventual manufacture, as we had to create a business around those costs.  We had aggressive cost targets, so we understood all of the processes and design constraints to develop the device in a technically superior, yet manufacturable way.  Some of the challenges we overcame were:

  • Embedding a circuit board in two overmolds to monitor and control temperature
  • Designing PCBs that could be overmolded without destroying thermistors
  • Designing overmolded, carbon-loaded plastic to be used as a heater. The thermal characteristics of the heater were dependent on the flow of the plastic in the mold.  The design features of the heater influenced how well it flowed.  To check the effectiveness of the part, test methods were developed to determine if the heater had the needed thermal characteristics.
  • Developing an inexpensive,, overmolded, inflatable bladder system that accurately delivered the precise amount of force in every inflation.
  • Cable management
  • Secure, reliable attachment to the LipiFlow treatment device
  • Using Gamma radiation compatible materials, which are also biocompatible
Wearable design for biocompatible lidwarmer pnuematic features

06


Manufacturing

The final act of setting the Activator up for success was ensuring that the manufacturing process was designed to produce quality medical devices and could be cost-reduced in the future as volumes grew. We set up a global supply chain, understanding how every penny was allocated within the process, then designed the cost-reduction pathway that is still followed today. That was only possible because we took a hands-on approach to manufacturing. We designed the test systems, the assembly systems, and the process, while the product was in development all the way through V&V and clinical builds. We use the same manufacturing approach on our projects now.

Some of the developments we made while manufacturing the Activator are:

 

  • An automated adhesive dispensing to lay a multi-dimensional glue bead and inspect it.
  • Proprietary processes for molding electrically conductive material and tests to confirm electrical molding accuracy
  • Two-shot processes for silicone over molding an inflatable bladder
  • An Asian supply chain for high labor components of the system
  • Final testing procedures and equipment, replicating the exact scenarios the devices would see in use.
  • A product tracking system that would accompany individual devices through their manufacture and into the field.

07


A Note about Blur and TearScience

The Blur founders all originated from the successful ophthalmology start-up TearScience, which was acquired by Johnson & Johnson Vision in 2017. We were key members of the engineering team responsible for its commercially successful product line and TearScience remains our client today. We developed the science, engineering and manufacturing systems behind their diagnostic capital equipment, imaging products and high-volume disposable treatment product. Many of Blur’s current employees, clients, and vendors are a result of the relationships we developed and fostered during our time there.