Science and Technology: Medical Devices (Part 4)

Medical Devices

Digital Hearing Aid (1987)

A digital hearing aid isn't automatically superior to analog devices. But starting with the creation of the Nicolet Phoenix the first digital hearing aid in 1987, the devices have become increasingly sophisticated. Much of this owes to digital signal processing technology, which has allowed manufacturers to enhance features and provide users with more comfort and higher-quality hearing. For example, digital hearing aids can drastically reduce feedback while the listener is wearing the device and enhance speech based on temporal or spectral content. The Lyric is the only extended wear hearing device on the market it can be worn continuously for up to 120 days.

Ventricular Assist Device (1992)

A ventricular assist device (VAD) is a mechanical pump that helps a weak heart pump blood through the body. It is often called a “bridge to transplant” because it can help patients survive until they get a new heart. The BVS 5000, a biventricular assist system manufactured by Abiomed, was the first VAD to earn FDA approval. It has supported thousands of patients since entering the market. Most recently, VADs have evolved to provide long-term support to patients with congestive heart failure.

Medical Lasers (1995)

Even now, many industry observers say that the surface has only been scratched with medical lasers and their potential. Medical lasers (light amplification by stimulated emission of radiation) use focused light sources to treat or remove tissue, and they are used for a variety of vision, dental, cosmetic, and general surgery procedures. One benefit for surgical procedures is less bleeding; heat from lasers cauterizes blood vessels, which leaves medical personnel with less blood to deal with compared with scalpels. Perhaps the most popular application is LASIK, a type of refractive laser eye surgery to correct myopia, hyperopia, and astigmatism. LASIK surgery has transformed outcomes for patients suffering from these conditions. FDA approved the first excimer laser in 1995.

LightCycler Real-Time PCR (1998)

Molecular diagnostics have paved the way toward individualized medicine. The technology enables point-of-care diagnoses for infectious diseases, meaning infected patients can be identified quickly, enabling immediate treatment and protection for those at risk. One of the best-known devices is the LightCycler Real-Time polymerase chain reaction (PCR) System from Roche Diagnostics. Using PCR, scientists can take a specimen containing a minute amount of genetic material, repeatedly copy a selected region from it, and within hours, generate a sample sufficient to perform a variety of tests. PCR is versatile. Many types of samples (e.g., blood, skin cells, saliva, hair) can be analyzed for nucleic acids. Any sample used for PCR must contain the DNA strand encompassing the region to be amplified.