Biomedical Engineering News

The Food and Drug Administration has given Teleflex Incorporated the green light to use their Chlorag+ard™ technology on peripherally inserted central catheters for human use. ArrowEVOLUTION PICC is similar to other PICC lines with one distinct advantage: it is impregnated with chlorhexidine molecules. Chlorhexidine is a potent antimicrobial agent that has been used in clinical and research settings to disinfect and sterilize medical equipment. The devices should be available on the market by the end of 2010.

Peripherally inserted central catheters or PICC lines provide intermediate and long term venous access in patients. PICC lines are longer than peripheral IVs with tips that extend to and terminate in central veins. Unlike central venous catheters, however, PICC lines begin in the veins of the limbs. This unique configuration means that they can deliver antibiotics that would be harmful to small veins, parenteral nutrition (food into the veins), and even chemotherapy. PICC lines are easier to insert and have fewer complications than central lines.

Historically, the main complication with long term use of PICC lines was that they could become colonized or laden with bacteria or other microorganisms. When a PICC line becomes infected, it must be removed, the patient’s medication administration is delayed, and the patient may need specific antibiotic or antifungal treatment for the catheter-related infection.

The promise of a chlorhexidine-coated catheter is that the PICC line could be left in place longer as the risk of catheter-related infections decrease. Since the catheter itself is the microorganism’s portal to the bloodstream, the Chlorag+ard™ technology should create a harsh, local environment for microbes and keep the PICC line relatively sterile.

By clearing the product, the FDA has essentially said that it is reasonably safe for use in patients. Only time and clinical research will show if ArrowEVOLUTION PICC lines are actually effective in reducing catheter-related infections.

While injectable drugs for multiple sclerosis (MS) have been available for some time, but Novartis’ fingolimod (Gilenya) is the first oral MS drug approved by the FDA. Gilenya has been shown to slow the progression of MS and to reduce the number of flares that patients experience during the course of the disease. As the first oral medicine that treats the disease rather than just treating symptoms, Gilenya may free patients from the need to give themselves regular needle injections in order to control their disease.

MS is a chronic neurological illness in which the immune system attacks and interferes with the myelin sheath that covers nerve cells in the central nervous system. Similar to an electric cord that no longer has its covering, the bare, myelin-less neurons do not send electrical information properly. This causes a number of neurological problems, from blindness to movement disorders, depending on the nerves that are affected.

Gilenya is a superagonist of sphingosine-1-phosphate receptors on the surface of white blood cells, specifically thymocytes and lymphocytes. White blood cells are one of the main tools of the immune system. In MS, they participate in the attack against myelin. In contrast to an agonist which stimulates a response in a biological tissue, a superagonist stimulates an exaggerated response—beyond what the biological tissue normally produces. Gilenya reduces the number of circulating white blood cells lymphocytes, which means there are fewer cells around to attack myelin and cause symptoms of MS.

While most neurologists have been impressed with the drug’s effectiveness, there is still concern about the side effects. Two patients that took the drug during the study died of diseases that their immune systems normally would have cleared, while other illnesses occurred as a result of depressed immune systems. In other words, Gilenya blocks the autoimmune attack on myelin but may inhibit the immune system to a degree that it cannot fight of infections.

Novartis has already agreed to a five year 5 post-approval safety study for the drug that will follow patients on the drug all over the world. As with any new drug, surveillance of side effects is important to determine the long term safety of the drug. For patients with MS that do not tolerate needles, Gilenya provides the first hope of managing the disease without needles.

Hearing impairment is a medical condition in which patient is unable to detect some frequencies of sound which are normally other humans can detect. The severity of hearing impairment can vary in different individuals and is more commonly found in age group above 50 years. Besides age related onset, it may also be caused due to disease like measles, meningitis or mumps. Trauma to the auditory system or side effects of some medicines like aminoglycosides, diuretics, aspirin and certain macrolide antibiotics can also produce hearing impairment.

People affected with hearing impairment frequently experience emotional conflicts, isolation and depression due to inability to hear voice coming through telephone, more specifically when using the Internet Protocol for voice over internet communications. Using conventional hearing aid and cochlear implants does not solve this problem because increasing the volume of voice coming through internet telephony also increases background noises.

Fraunhofer Institute for Digital Media Technology has now developed next generation digital hearing aid solution, known as Speech-Improved Telephony. This technology uses algorithms to compensate for those sound frequencies which are detected by patient with greater difficulty. It amplifies the softer sound frequencies to make it more easily detectable by hearing impaired patient, without intensifying the louder sound frequencies. These algorithm parameters can be adjusted by patient himself in a user-friendly manner according to his own specific hearing frequency disability.  To make this technology more user friendly, these algorithms can be integrated into all commonly used devices like iPod Touch system, telephone system or audio conferencing system.

The knee joint being the heaviest joint in the body, carries about half of the body’s weight and is consequently most susceptible to injury, damage or wear. Knee implant surgery is commonly done for patients suffering from pain and disability caused due to damage to knee cartilage from rheumatoid arthritis, osteoarthritis, or trauma.

During the knee implant procedure, damaged and worn out weight bearing surfaces of the bone are replaced by implant made of clinical grade titanium. The lifespan of such implant depends on how well the titanium implant surface is able to integrate with the bone.

Normally such implants have a life span of about 15 years after which risk of loosening of implant or wear of implant increases significantly. According to available statistics, about 20 million Americans of age above 45 years are affected by osteoarthritis. It can be inferred that patients of age group 45 years to 60 years may have to undergo second surgery to replace the first implant after using the first implant for about 15 years.

According to the research done at Georgia Institute of Technology, it may no longer be necessary to undergo a second surgery to replace the first implant after 15 years.

Researchers at Georgia Institute of Technology have developed new improved titanium implants for knee replacement whose surface is coated by three or five self-assembled tethered clusters of the engineered fibronectin protein. This coating by clusters of fibronectin protein at the nanoscale level helps to promote bone formation around the implant, resulting in implant to be fixed twice as securely as compared to implants made from bare titanium. This coating helps to significantly increase the life span of an implant procedure much beyond 15 years period.

Source:  Journal Science Translational Medicine.

Vitrectomy is the surgical removal of the vitreous gel from the middle of the eye. This surgical treatment is usually required in patients who have retinal detachment, retinal tears, bleeding in the vitreous gel, or severe scar tissue formation on the retina.

Bausch + Lomb have now introduced the new, Stellaris(r) PC (Procedural Choice) Vision Enhancement System to eye surgeons.  This system has been named PC (Procedural Choice) Vision Enhancement System because it gives choice to the eye surgeon to perform vitrectomy or cataract surgery in a single compact system using most advanced technology.

This Stellaris(r) PC Vision Enhancement System has an innovative design with wireless foot pedal which allows it to occupy less space. It can be quickly installed either in a mobile surgery unit or in a hospital operating room at lower cost. This feature makes it accessible to greater number of patients at lower treatment cost.

For the surgeons, this Stellaris(r) PC Vision Enhancement System allows better visibility of eye tissue while performing surgery because it is fitted with dual light source and color filters. This system comes with revolutionary Stable Chamber(TM) tubing system which facilitates the eye surgeon to make the smallest incisions for both retinal and cataract surgeries. This was not possible with traditionally available bio-medical devices.  This facilitates better clinical outcome with highest precision.  This system comes with vitrectomy probes which can operate on ultrahigh-speed and have very light weight. This significantly improves the success rate of transconjunctival vitrectomy procedures.

Sudden cardiac arrest is a medical condition in which the patient’s heart suddenly stops beating, as a result of which blood flow does not reach brain and other vital organs. It is estimated that more than seven million people die every year worldwide due to sudden cardiac arrest. In 95% of cases, patients who suffer sudden cardiac arrest can die within minutes if immediate treatment with defibrillator is not provided.

Until recently, automated external defibrillators were used to save lives of patients suffering from sudden cardiac arrest. These automated external defibrillators were applied externally on human body to send electric shock to heart of the patient in an effort to restore normal rhythm of heart.

Now InnerPulse, Inc. has introduced Percutaneous Implantable Cardioverter Defibrillator device for the treatment of sudden cardiac arrest. The Percutaneous Implantable Cardioverter Defibrillator is effective in treating ventricular tachycardias and minimizing the chances of sudden death.  Implanting a Percutaneous Cardioverter Defibrillator is also effective in treating patients with reduced left ventricular function who survive a myocardial infarction.

This innovative device can be placed inside the human body with minimally invasive surgery in a very short time. The Percutaneous Implantable Cardioverter Defibrillator can be completely encapsulated in a catheter and inserted in the human body intravenously through a vein in the leg. This procedure significantly reduces the cost of treatment and makes this device more accessible to greater number of patients at risk.

Source : InnerPulse, Inc.