Medical Product Development Information
Medical OEM customers often approach ITI for help in developing and manufacturing their medical device. Most of the time, their inquiries can be classified as one of the following tasks:
- Design and manufacture a scope to the customer's unique specifications
- Add visualization capability to the customer's medical device
- Produce an articulating endoscopic device that will deliver the customer's technology
in a minimally invasive manner
Following is a discussion of the product development process that we would typically use to help the customer take their device from concept to production. It will also remind potential customers of the kind of information we need prior to being able to quote a new project.
Execute Non-Disclosure Agreement
In many cases, a discussion about a customer’s application or device design will first require execution of a Non-Disclosure, or Confidentiality, Agreement. ITI typically enters into mutual non-disclosure agreements, meaning confidentiality is observed in both directions of the information exchange – from the customer to ITI and vice versa.
Define Optical Specification
If the customer needs an optical scope, or needs to add the capability to see to their own product, we will review basic optical specifications. These include:
- Field of View - Typically expressed in degrees, this spec describes how much of the target area should be visible.
- Line of Sight - This describes which way the scope or optical system is looking, relative to the distal tip of the device. Typical examples are Forward (0°), Right Angle (90°), and Forward Oblique (45°).
- Object Distance - How far away from the distal tip of the device is the target area?
- Resolution - How small is the object you are looking at? This will typically define the required resolution of the optical system or camera to be used.
If cameras are used, expect one of three possible design approaches: coupling a camera to a standard scope eyepiece, removing the eyepiece and installing the camera directly to the proximal end of the scope, or installing a camera on to the distal end of the scope itself.
In either case, besides the optical specifications listed above, be prepared to discuss the specifications of the current camera and monitor system, so that the optical system of the new device will be designed to be compatible with the existing camera and monitor. If there is no existing system, the type of camera to use will largely be determined by the resolution requirements of the application itself.
The last optical specification to consider is lighting. Since most endoscopic medical devices operate within an enclosed body cavity, or inside an organ, lighting will be necessary. Most scopes use an external light source that is connected to the light post on the proximal end typically with a fiber optic “light guide,” located usually on or near the control handle. In turn, the light is relayed down the scope’s insertion tube and focused at the distal end. Traditional light sources may be large, heavy and cumbersome. However, in some cases the higher light output of these systems is necessary to properly illuminate the target areas.
Another alternative to consider in lighting is a light source that uses light emitting diodes (LEDs). In recent years, LED designs have advanced to the point that they can now adequately serve many lighting requirements. In the case of scopes, LEDs may be installed at the distal tip, or remotely, like a traditional light source. LED systems are compact, generally use less power, and last much longer than traditional light sources.
ITI can help explore all possible lighting alternatives as you review the specifications of your device and the requirements of the application.
Determine Mechanical Specifications
The mechanical specifications of your new scope or medical device can obviously be just as important (or even more critical) than the optical specs. For example, many applications call for working within very tight spaces, or perhaps the scope or medical device may have to navigate a fairly circuitous path to get to the target area.
Here is a basic list of mechanical specifications that have to be defined:
- Insertion Tube Diameter - This is determined by the smallest cavity that the scope or medical device is inserted in.
- Working Length - Define this specification based on the minimum length needed to perform the procedure correctly, plus some allowance to ensure that all possible anatomical types are considered.
- Articulation - This capability allows easier insertion into the anatomy, and efficient navigation to the target area. If articulation is required, please define the following:
- Number of articulation directions - Either two-way or four-way. Four-way articulation is more versatile, but it is also more mechanically involved, thereby adding complexity, cost, and possibly size.
- Articulation range - Usually expressed as number of degrees in each of the needed directions (e.g., Up / Down / Left / Right).
- Actuation method - Typically, scopes are articulated using either knobs or levers located on the control handle. We will need to define which knob or lever is responsible for which articulation direction. Also, sometimes articulation can be actuated using servo motors and a “joystick” control. However, this approach is probably more costly and it tends to limit potential applications to those that do not require as much wire pulling strength.
- Specialized channels or lumens - Do you need specialized channels to do other types of work? For example, if you need to use tools such as graspers, forceps, nets or snares, then an instrument channel will be required. Sometimes, your procedure may also call for an insufflation or irrigation step, in which case separate air or water lines may also be required. Typically the minimum diameter should be defined for specialized channels or lumens. If they will be used as air or water lines, also define the maximum pressure and flow rates that are expected.
- Marking - Specify how you want the insertion tube or working length to be marked. This will be helpful in determining how deep the scope or device is inserted, thereby giving the operator an idea of where the distal tip is, relative to the target area.
- Terminations - Another set of mechanical specs to define would be how each of the device’s features is terminated at the proximal end. For example, if there is an instrument channel or air and water lines, would you require a luer lock to provide a sealed interface? What type of light source is used, and how is it connected to the device? If the device is camera-based, what kind of video output connector is needed at the proximal end to interface properly with the monitor?
Biocompatibility and Chemical Compatibility
By nature of the applications they are used in, medical devices usually enter, or make contact with, some parts of the human body. As such, we will have to ensure that all components of the medical device considered patient-contact, should be biocompatible. ITI’s medical OEM customers are responsible for defining the biocompatibility standards that their medical device has to comply with, including requirements for design validation testing.
Likewise, the customer also defines the chemical environment that the device is expected to be exposed to, especially which particular cleaning, disinfection, and/ or sterilization methods will be used.
The ITI engineering team will select possible patient-contact materials to use in the device design after the customer has defined both biocompatible and chemical standards.
Concept Validation and Prototype Stages
A thorough review of your market and/ or regulatory requirements should give you an idea of how many prototypes you will require during the initial stages. A certain number of prototypes may be needed to prove the concept to your target market. For example, you may choose to have a small focus group of doctors or specialists evaluate the device prior to a more formal market introduction. This evaluation period may be used to finalize the product specifications prior to finalizing the device design, filing the necessary regulatory applications and performing clinical trials (if necessary).
As the design is finalized, it would help to review your ramp-up schedule with ITI, as that will help determine the appropriate fabrication methods to use at each stage. For example, if small volumes are anticipated for the first several years, then it may be cost-efficient to stay with more traditional machining methods for fabricating component parts; as volumes increase, it may be worthwhile to switch certain component parts to plastic injection molding or other lower cost / high volume manufacturing methods.
In addition, a review of your ramp-up schedule will also allow ITI to anticipate when it will be necessary to add production resources, and plan accordingly.
Product Design Improvements
With all the work that goes into assuring that your medical device design is as good as it can be, after some time in the market, one should anticipate that certain product improvements will be necessary. Rest assured that the ITI engineering and manufacturing groups are properly equipped to support our medical customers in upgrading product designs based on market feedback or evolving needs.