Improved Light Delivery
Nanoptics has recently developed a higher numerical aperture plastic optical fiber that delivers more light than ever. It is ideal for use in 25-gauge devices. Below are three examples of major medical areas benefiting from greater light delivery through custom diameter fiber for 25-gauge devices.
Vitreoretinal surgery instrumentation has migrated to smaller and smaller diameters in the last two decades. Excellent instrumentation now exists based on 25-gauge devices. This corresponds to plastic optical fiber with a 170 micron diameter. As the diameter of fiber is reduced, the light delivered is reduced. Because of brighter light sources and new materials employed in fiber manufacture, more light can be delivered to the eye. Additionally, it is possible to tailor the fiber to deliver better illumination quality over a larger diameter of the surgical field. All of this has provided safer eye surgery.
Delivery of light to the distal tip of an endoscope is often performed using plastic optical fiber. The illuminated field can be easily controlled in brightness and wavelength distribution by the external light source. Due to the need to minimize the external diameter of the endoscope, it is frequently desirable to use a non-standard diameter of the plastic optical fiber. In this way, uniform field illumination and maximum brightness can both be achieved simultaneously.
Photodynamic therapy (PDT) is a relatively new treatment for a wide variety of diseases. It usually involves administration of photosensitizing drugs which are selectively taken up by diseased tissue. When light of a specific wavelength is absorbed by the drug, the diseased tissue is destroyed. The fiber must transmit high optical power, in a small wavelength range, from about 400 nm to 650 nm, and in some applications up to 800 nm. The diameter of the fiber usually must be much less than 1 mm to maintain high flexibility. Frequently, the fiber must fit within the working channel of an endoscope which permits visualization of the diseased tissue and treatment procedure. These constraints lead to optimization of the light delivery using non-standard diameter fiber and non-standard materials of the fiber.