LEDs in Medical Instruments

LEDs in Medical Instruments

Polar Ray Admin

A previous blog here touched on uses of LED lighting as general area lighting and as task lighting as used in the medical field. In this blog the use of LEDs in medical instruments will be the subject. The use of LED lighting in medical instruments brings about many changes in the lighting used for instrumentation in the past. Besides the factors of energy savings, longer life, less generated heat, small size, and better overall quality of light, the use of LEDs in medical instruments has even lowered the cost of devices in some cases. This cost reduction and the increase in intensity and other metrics has allowed the use of LEDs in places which were previously occupied by large, expensive, short lived, and bulky lighting techniques.

In the fields of endoscopy and laparoscopy, both minimal invasive surgery in which tiny lights, cameras, and surgical instruments are used for diagnostics and procedures within the body, the xenon light has been the choice among high intensity gas discharge lights for illumination in the procedures. The light that is used in the procedure is created by a small bundle of fiber optic which needs to be coupled to an enormously bright light source. Xenon lights with a rating of 180-300 watts are the choice for power. It is necessary for the light source to deliver in excess of 1000 lumens in order to make the light at the end of the fiber bundle useable. Although the xenon light is up to the task of meeting all the necessary requirements for endoscopy and laparoscopy procedures, the xenon lifetime is quite short – around 1000 hours - and replacement cost is rather high. The introduction of LEDs for the light has greatly improved the lighting necessary for endoscopy and laparoscopy procedures. One such design has a specially developed line of ultra-high performance LEDs which are able to easily replace the xenon lighting technology. The LED developed for the job is able to generate 300 lumens per square millimeter over an area of approximately 8 square millimeters. The LED chips for the applications are also designed to be driven at a current higher than would normally be used for general LED lighting. As simple as it sounds to transmit light down the length of a fiber optic bundle, quite the opposite is true, as it is a difficult feat to properly couple a light source to a fiber optic bundle and optimize the transfer of the light produced. To this end the company has produced specific LEDs to properly transmit the light through the fiber cables. The next challenge for engineers working in this area is to develop a coupling technique which allows for more efficient transmission of the light.

Since the medical field commonly uses the highest grade of lighting for all applications, it is with open arms that the field sees the LED lighting advancements that are increasing the accuracy that the LED lighting can improve. The current use of the gas discharge illumination for the endoscopy and laparoscopy procedures leaves something to be desired in the efficiency, ergonomics and color output ability. In regard to color output - actual visual color (violet, etc.) not color temperature (4000K, etc.)  there are particular diseases which are detected with different colored light and LED lighting is quite capable of producing colors which the xenon lights are not particularly well suited for.  The change to LED lighting which can be adjusted to the desired color could be the difference between properly diagnosing a condition, as the LEDs have the advantage of being able to provide contrast enhancements which are required for imaging tissue of different kinds. It is quite possible that endoscopy and laparoscopy procedure lighting could be controlled as is possible with current types of LED surgery room lights which are programed to change color temperature by voice command, to suit the situation or the individual surgeon’s preference.

A technique which is in early stages of development, known as capsule endoscopy, places a tiny camera and LED light in a capsule that a patient swallows. As the capsule travels through the gastrointestinal tract it is capable of capturing images of areas which cannot be imaged with any other methods. Transmission of the images is accomplished with Bluetooth technology via a live stream to a viewing monitor or monitors. The LED lighting in the capsule has improved the technique, and the future possibilities also become more varied and exacting with the quality of the light which is able to be produced. The future use of LED lighting in the endoscopy and laparoscopy fields is very promising. The ongoing research and engineering work to address improvements in further miniaturization and optimized illumination to increase the ability to view areas with greater detail will continue to improve medical procedures and LED lighting is a huge part of the advancements.

This was a continuation of the blog entitled, Medical LEDs, and there will, likely, be more medical LED use blogging in the future. The medical field is one that is experiencing a huge and important increase in the ability to diagnose and cure more easily and efficiently than ever before due to advancements in the LED field.

As always, if you need help with your LED lighting projects, please feel free to call Polar Ray at 303-494-5773 to speak with a lighting consultant. Thank you for perusing the Polar Ray website.