The electronic eye

Electric Eye: Retina Implant Research Expands in Europe, Seeks FDA Approval in U.S.: Scientific American
scientificamerican.com


CHIPPING AWAY AT BLINDNESS: There is no effective treatment for retinitis pigmentosa, but researchers such as those at Retina Implant, AG, are making great strides to remedy this through implants that stimulate still-active nerves in the retina, the layer of tissue at the back of the inner eye. Image: Courtesy of Retina Implant, AG

Promising treatments for those blinded by an often-hereditary, retina-damaging disease are expanding throughout Europe and making their way across the pond, offering a ray of hope for the hundreds of thousands of people in the U.S. left in the dark by retinitis pigmentosa. The disease—which affects about one in 4,000 people in the U.S. and about 1.5 million people worldwide—kills the retina’s photoreceptors, the rod and cone cells that convert light into electrical signals, which are transmitted via the optic nerve to the brain’s visual cortex for processing.

There is no effective treatment for the condition, but researchers are making great strides to remedy this through implants that stimulate still-active nerves in the retina, the layer of tissue at the back of the inner eye. In mid-November Retina Implant, AG, got approval to extend the yearlong phase II human clinical trial of its retinal implant outside its native Tübingen, Germany, to five new sites—Oxford, London and Budapest, along with two additional locations in Germany.

The company’s implant is a three- by three-millimeter microelectronic chip (0.1-millimeter thick), containing about 1,500 light-sensitive photodiodes, amplifiers and electrodes surgically inserted beneath the fovea (which contains the cone cells) in the retina’s macula region. The fovea enables the clarity of vision that people rely on to read, watch TV and drive. The chip helps generate at least partial vision by stimulating intact nerve cells in the retina. The nervous impulses from these cells are then led via the optic nerve to the visual cortex where they finally lead to impressions of sight.

Thus far, some patients report having a narrow field of vision partially restored, providing them with enough acuity to locate light sources such as windows and lamps as well as detect lighted objects against dark backgrounds. The chip’s power source is positioned under the skin behind the ear and connected via a thin cable.

Window on the world
For those suffering with retinitis pigmentosa, Retina Implant’s technology creates a small black-and-white window on the world, says Eberhart Zrenner, the company’s co-founder and director and chairman of the University of Tübingen’s Institute for Ophthalmic Research in Germany. Retina Implant has successfully placed chips beneath the retina of nine patients since May 2010. A 10th patient experienced a problem when their optic nerve did not forward the information on the chip to the brain.

Looking ahead, Zrenner hopes to widen patients’ field of vision further. “Because our chip has independent miniature photodiodes, we could arrange three of them in a row beneath the retina,” he says. The ability to produce accurate colors via retinal implants, however, is very complicated and may not be possible for years, he adds. Retina Implant has also developed an outpatient treatment for early-stage retinitis pigmentosa called Okuvision, which uses electric stimulation to help preserve retinal cells.

Sights set on the U.S.
The phase II extension expands Retina Implant’s trial to an additional 25 patients beginning early next year and follows a partnership the company struck in March with the Wills Eye Institute in Philadelphia. Wills is looking to become the lead U.S. clinical trial investigator site for Retina Implant’s technology and to help the company through the U.S. Food and Drug Administration’s (FDA) review process.

Cutting-edge technologies such as sub-retinal implants are typically at a disadvantage when seeking FDA approval due to the lack of a track record, but Retina Implant’s work in Europe provides a precedent for the FDA to consider, says Julia Haller, Wills’s ophthalmologist in chief. “There’s information available to U.S. regulators about how patients have responded so far,” she adds.


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Check out these free health apps.

If you have an iPhone, iPod or iPad, there are three free apps that may well be worth downloading.

The first is Itriage, the second is ICE standard, and WebMD. Check them out.



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Doctors, Like Their Patients, Use Google for Health Information

Doctors, Like Their Patients, Use Google for Health Information - Health Blog - WSJ
By Katherine Hobson

Doctors: they’re just like us!

General web browsers like Google and Yahoo are behind only professional journals and colleagues as a source of information physicians frequently use to diagnose and treat patients, according to a survey of more than 300 doctors.

The survey, from Wolters Kluwer Health, covered a sample of American Medical Association members, both primary-care physicians and specialists. We weren’t too surprised to hear that “spending more time with patients” ranked highest on a list of areas in which doctors would like to see improvement. Nor was it particularly shocking to read that expense is a big barrier to adopting new health technologies.

But the Google and Yahoo findings initially surprised us. When doctors were asked how often they used certain sources to gain information used to diagnose, treat and care for patients, 68% said they “frequently” consulted professional journals and 60% said the same about colleagues. And just under half — 46% — said general web browsers. Conferences and events and online free services like WebMD were each cited by 42% of respondents as frequent sources of information.

Then again, no one says Google and Yahoo don’t lead people to tons of useful info — just that it can be tough to sort the wheat from the chaff. Physicians, presumably, can assess the quality of the health information they dig up better than the average consumer.
On that topic, the survey also asked whether improved access to medical knowledge by patients has a positive impact on the doctor-patient relationship: 53% said yes. About a fifth think it has “been detrimental, leading to misinformation and incorrect self-diagnosis,” the study found.


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A 3-D Printer Makes Customized Human Bones To Order

A 3-D Printer Makes Customized Human Bones To Order |
Popular Science
popsci.com


By Clay Dillow Posted 12.02.2011 at 9:59 am


This Machine Prints Bones via WSU
We’re already printing organs to order, so why not Cmd+P some customized 3-D bone? Washington State University researchers have tweaked a 3-D rapid prototyper designed to create metal parts to print in a bone-like material that acts as a scaffold for new bone cells. In just a few years, the researchers say, doctors and dentists could be printing up custom bone tissue to order.

Reported in the journal Dental Materials, the bone-like material appears to cause no negative side effects and eventually dissolves. But before doing so, it serves as a scaffold for new bone cells. Placed in a medium of immature human bone cells, the printed structures encourage the growth of new bone that fuses with existing bone tissue.

“If a doctor has a CT scan of a defect, we can convert it to a CAD file and make the scaffold according to the defect,” Susmita Bose, co-author and professor in WSU’s School of Mechanical and Materials Engineering, said in a press release.
In terms of potential for regenerative medicine, that’s fairly huge. It opens the door to the ability to create perfect—or nearly perfect—replacement implants for damaged or deformed bone tissue and grow new, corrective bone that is the real thing rather than a ceramic or metal analog. And the procedure is relatively fast. Networks of new bone cells reportedly grew within the 3-D printed structures within just a week of placing them in a culture with immature bone cells.

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The Future of Medicine

Megatrends: The Future of Medicine: Megatrends in Medicine - by Dr. Stephen C. Schimpff, MD
medicalmegatrends.com

The Megatrends - The Future of Medicine

Over the next decade, medical care will improve rapidly and dramatically, thanks to advances in genomics, stem cells, vaccines, medical devices, imaging and new approaches in the operating room.

What will these megatrends mean to you?

Genomics will allow tomorrow’s physician to predict at birth or before what major diseases a person is likely to develop, such as coronary artery disease. Vaccines will be created specifically to treat an individual person’s cancer. Stem cells will be used to regenerate a specific tissue lost to trauma or disease.

Surgery will be based on the individual’s own CAT scan image which will be used first to simulate that individual’s proposed operation, then to practice it to perfection and then to program a robot to assist. Drugs will be created to attack a specific target and will be prescribed for the individual patient based on genomic knowledge of their disease and how their body will respond to the specific drug – more effective, less side effects and much safer.

Preventive medicine will advance rapidly as genomic information tells what an individual is likely to develop over time. Then the physician can prescribe a personalized preventive program for that person such as life style changes to prevent coronary artery disease or early institution of colonoscopy for the person at very high risk of early colon cancer. Vaccines will be available to prevent increasing numbers of serious infectious disease but also to prevent atherosclerosis, some cancers, and can be used to help treat or prevent some chronic conditions like Alzheimer’s, multiple sclerosis and even drug addiction.

Surgical advances will allow repairs never available before such as replacing heart valves with minimally invasive surgery rather than today’s’ open surgery with heart lung bypass. Stem cells will mean that a pancreas deprived of its islet cells can be replaced with cells that will create insulin as the body requires. Stem cells will also repair the heart after a heart attack. Organ transplants will no longer depend another person’s else’s death; rather the organ will be produced in a pig raised specifically to have an organ that will not cause rejection after transplant – more functional and no need for anti-rejection drugs.

Your medical information will finally all be digitized and instantly available any time and any place either via the internet or placed on a chip embedded in an ID card in your wallet. This will include not only your doctor’s notes but copies of your images from radiology, colonoscopy, or surgery along with a base line CAT scan taken at age 18 that can be compared to later when trauma or disease strikes. It will also include your entire genomic information. And it will be available only with your release of the password.

Finally, medicine will become truly safe. A full change in culture will make safety issue number one and this will be augmented by new technologies that will assist the healthcare provider to make care safe. Included will be access to your medical information at a moments notice, use of new drugs and vaccines designed for you based on your genomic information, use of robots in surgery that cannot make errors and the use of simulation to assist doctors learn new techniques and procedures.

The result will be a new era in medical care, one where the patient comes first, is safe, can be assured that a medicine will work without side effects, that surgery will be custom tailored and where real attention will be paid to preventing disease before it occurs.

Stephen C. Schimpff, M.D.


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Artificial pancreas could be 'holy grail' for Type 1 diabetics

Artificial pancreas could be 'holy grail' for Type 1 diabetics - CNN.com

By Saundra Young, CNN Medical Senior Producer
updated 8:31 AM EST, Sat November 26, 2011

A trial patient for the Juvenile Diabetes Research Foundation’s Artificial Pancreas Project tests the device.

(CNN) — Kerry Morgan was just 3 years old when she participated in her first clinical trial for type 1 diabetes prevention. She didn’t have the disease, but her 7-year old sister did and there was concern that she might develop it, too. During the trial she was given one shot of insulin a day in the hope that it would stave off the disease, but a year later, she was officially diagnosed.

“I remember a lot of things changed.” Morgan said. “I went from having juice every day and M&Ms to not having sugar at all. I remember getting shots every day, finger pricks, my parents had to hold me down.”

School, she says was difficult. “You had to let teachers know what was going on. You had a special relationship with the nurse because she had to check your blood sugar every day before going to lunch.”

At 14 she entered a second trial, this one at the University of Virginia, for a continuous glucose monitoring system called The Navigator. It was at UVA that she first learned about the artificial pancreas. A high school senior at 18 now, she has participated in four clinical trials and two have involved artificial pancreas systems.

“It was awesome. I’ve never done anything quite like it before. For the two days that I was on the artificial pancreas I experienced normalcy. I wasn’t checking myself every five seconds and giving myself insulin because it was doing it for me.”

In type 1 diabetics, the pancreas makes very little or no insulin, a hormone that controls glucose levels, or the amount of sugar in your blood. Patients must constantly check their levels throughout the day, determine how much insulin they need to lower their blood sugar and administer the proper amount using a pump or syringe. Drops or spikes in blood sugar can be extremely dangerous. If the level is too low — a condition called hypoglycemia — patients can experience shakiness, confusion, trouble speaking, seizures, even coma and death. A level that is too high — hyperglycemia — can cause excessive thirst, frequent urination and cardiac arrhythmia. Left untreated, hyperglycemia can lead to a number of serious complications including vision loss and nerve damage.

An artificial pancreas mimics the glucose regulating function of a healthy pancreas. The automated device features a sensor that’s placed under the skin that measures blood sugar. Information from this continuous glucose monitor is sent to a receiver and an insulin pump delivers insulin in controlled amounts. A glucose meter calibrates the sensor. Sophisticated software checks the blood sugar in the body and automatically provides the correct dose of insulin needed at the right time.

“When you have diabetes, every second you’re thinking about your blood sugar,” says Morgan. “You’re wondering if you’re high, if you’re low, if you’re OK, if you’re giving yourself enough insulin, if you’re not giving yourself enough insulin. With the artificial pancreas it takes that worry away because it’s doing it for you. It lets you know if something’s wrong. That way you’re not always worrying about your blood sugar.”

The device has not yet been approved by the U.S. Food and Drug Administration. In June the agency issued a draft guidance seeking input from the industry and researchers on an early version of the artificial pancreas, called the low glucose suspend system. It’s a backup for diabetics experiencing hypoglycemia. Patients still have to monitor their levels and give themselves insulin if necessary, but the low glucose suspend system temporarily reduces or stops the insulin flow in the event of an episode.

There are two types: A reactive low glucose suspend system that stops insulin infusion when a predetermined level has been reached, and a predictive low glucose suspend system that anticipates a hypoglycemic event based on the current blood sugar level and how fast those levels are falling.

Dr. Charles Zimliki chairs the FDA’s Artificial Pancreas Critical Path Initiative and he is a type 1 diabetic. Testifying before a Senate committee in June, he said the FDA is committed to seeing the device come to market but is proceeding with caution.

“While the potential benefits are enormous, an artificial pancreas system is considered a significant-risk device, meaning it presents a potential for serious risk to the health, safety or welfare of a patient. If not properly designed, use of an artificial pancreas device in an outpatient setting can place patients at significant risk, because the device controls the administration of insulin without the oversight of health care professionals.”

The FDA is expected to release new guidance for future generations of the artificial pancreas systems on December 1. The Juvenile Diabetes Research Foundation has been working closely with the FDA on the artificial pancreas. It says low glucose suspend systems have been in use in more than 40 countries for the last 2½ years and the process in the United States is taking much too long.

“Here in the U.S. we’re now almost three years behind and the first study to test these systems is just going to launch in the next month, which means it’s going to be another year or so before patients even have access,” said Aaron Kowalski, assistant vice president of treatment therapies for the foundation. “What JDRF is advocating for is to ensure that people here in the U.S. have access to these tools in a timely manner.”

The FDA says other countries have different regulatory systems in place that do not require the same safety and effectiveness data for a product of this level of risk.

Tom Brobson, a 51-year-old Christmas tree farmer and the national director for donor relations at JDRF was diagnosed eight years ago with type 1 diabetes. “I think they’re getting hung up on better when good enough can do the job. You can’t get better until it’s out there being used. We know that technology isn’t perfect, but what we’re talking about are significant improvements and enhancements over what we have today that can significantly reduce the daily burden of living with this disease, improve quality of lives and save lives.”

Brobson has been participating in artificial pancreas clinical trials at UVA since 2007. “It’s been awesome, fantastic, frankly everything I could ever imagine it to be and then some,” he says. “The open question for me was could a computer system using off-the-shelf technologies do a better job of controlling my blood sugar than I was already doing for myself and the answer turned out to be overwhelmingly yes.”

Without it, Brobson says he has to spend every minute managing his diabetes. “I have to be my own pancreas 24 hours a day. Last thing at night, first thing in the morning and often in the middle of the night. When the artificial pancreas took over, that was a real power moment. It kept me perfect from 8 p.m. to 8 a.m. When the artificial pancreas took over moment to moment when it was actively assisting me in the management of my disease, it was a life changing moment and it was life changing because I didn’t have to think about my diabetes every moment of the day.”

Dr. Michelle Magee is an endocrinologist and director of the MedStar Diabetes Institute at Washington Hospital Center in Washington, D.C. “The data from other countries showed that the system could be used safely and effectively. It’s been somewhat disappointing that it has taken so long to get approval here.”

She says the long awaited system offers hope to patients. “For people with type 1 diabetes, the artificial pancreas has been kind of the holy grail of technology to support self management of diabetes. It’s not going to cure it, but it’s going to be a huge step in the right direction. Once it’s approved and can be used it will be fantastic.”

According to the Juvenile Diabetes Research Foundation, about 80 people a day are diagnosed with type 1 diabetes. Approximately 3 million Americans are living with the disease. Most of them only have healthy blood sugars 30% of the day. The foundation says it has spent $1.5 billion on diabetes research, $40 million of that on research on artificial pancreas systems.

“Our goal is to drive the development of artificial pancreas systems,” Kowalski said. “This could not only improve tremendously glucose control, and help reduce the risk of these terrible diabetes complications, it could also help people with diabetes live easier. The bottom line is diabetes is a 24 hour a day, 7 day a week, 365 day a year job and if we can make some of that easier that would be a huge step forward.”

Morgan agrees. “I think it’s superimportant, I think next to having a cure for diabetes it’s the big thing. Because it’s such an instrumental piece of equipment it can allow you to live closer to what we consider normal than anything that we have now.”



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How about a wireless pacemaker?

Next-Gen Cardiac Care Includes Wireless Pacemakers:
scientificamerican.com





WiCS: In the new pacemaker called the Wireless Cardiac Stimulation (WiCS) system, a wireless electrode replaces one or more leads. A conventional pacemaker is implanted just below the collarbone in the left side of the chest and sends out a signal through a lead running into the heart’s right side. The WiCS unit, implanted near the heart, wirelessly senses the pacemaker’s pulse via this lead; it then sends an ultrasonic signal to the wireless electrode on the left side, which converts the sonic energy into electrical energy to pace the left ventricle synchronously with the right. Image: Courtesy of Cambridge Consultants

Millions of pacemakers have been successfully implanted in the past half century to regulate erratic heartbeats, but the electrical leads, which connect the device to the heart, complicate the surgery and increase infection risks. The heart’s continuous and vigorous beating also creates strain on the leads and can damage them over time.

Now researchers seek to go wireless. In a new pacemaker called the Wireless Cardiac Stimulation (WiCS) system, a wireless electrode replaces one or more leads. California start-up EBR Systems, working with English technology-development firm Cambridge Consultants, recently announced their system was successfully implanted in 100 patients needing cardiac resynchronization therapy (CRT) during a series of human clinical trials in Europe. (Wireless signaling is not entirely new to pacemakers—doctors have for the past few years been able to communicate with them via the Internet or even smart phones.) CRT patients suffer from a type of chronic heart failure requiring both the left and right ventricles to be paced. Normally, such devices require the implantation of three leads, the trickiest of which is threaded through a complex route running from the right atrium, into the coronary sinus on the outside surface of the heart, and then to the left ventricle. In the new device, a small electrode inserted in the left side of the heart replaces one or more of the leads. In the system, a conventional pacemaker, implanted just below the collarbone in the left side of the chest, sends out a signal through a lead running into the heart’s right side. The WiCS unit, implanted near the heart, wirelessly senses the pacemaker’s pulse via this lead; it then sends an ultrasonic signal to the wireless electrode on the left side, which converts the sonic energy into electrical energy to pace the left ventricle synchronously with the right. Advances in low-power microelectronics and improved digital signal processing at high speed and low power enabled the system, says Andrew Diston, Cambridge’s director of global medical technology. The ultimate goal is to eliminate all wire leads, making the pacemaker easier to implant. Another goal is to integrate the functions of the conventional pacemaker and the WiCS into a single device. Wireless technology is notoriously tough on battery life. Diston says that most of the pacemaker’s battery—generally lasting seven or eight years before needing to be replaced—is still dedicated to monitoring the heart and deciding when to pace. The WiCS system has its own battery, and no modification to existing pacemakers is required, he added. Diston is hesitant to set a time frame for the system’s availability to the general public. WiCS continues to be tested in human clinical trials in Europe and will first be available there. Before it is made available in the U.S., it will need successful clinical trials here and approval from the U.S. Food and Drug Administration.

WiCS is potentially a disruptive technology, says Bruce Wilkoff, director of cardiac pacing and tachyarrhythmia devices at the Cleveland Clinic, who was not involved with the research. It is still immature, he adds, because it requires other components to coordinate the stimulation. Given that wireless technology is typically not as reliable as its wired counterpart, the largest concern involves the signal—whether the ultrasound will penetrate the heart muscle consistently and efficiently transfer energy to the wireless lead, Wilkoff says. Still, he adds, “I don’t think that there is any concern about safety.”

Pacemakers in general require patients to take certain safety precautions, such as not placing cell phones directly against the chest and avoiding strong electric or magnetic fields. Whereas some newer pacemakers are not affected by magnetic resonance imaging (MRI) scans, patients should consult their physicians before undergoing such tests. The addition of wireless to a pacemaker does not change the need to take these precautions.

Some experiments to “hack” into pacemakers capable of communicating wirelessly with computers and smart phones have been demonstrated by security researchers, but there have been no reported incidents of wireless pacemaker data being tampered with to the detriment of a patient. Still, researchers from the Massachusetts Institute of Technology and the University of Massachusetts Amherst say they are developing a jamming device that could be used to shield pacemakers from cyber attackers.

EBR and Cambridge are not only ones working on wireless pacemakers. Minneapolis-based Medtronic, Inc., last year introduced plans for a small, self-contained and fully leadless pacemaker the company hopes to market within three or four years. The Medtronic titanium-encased device will have a circuit board, an oscillator to generate current, a capacitor to store and rapidly dispense charge, memory to store data, and a telemetry system to wirelessly transfer that data to a computer or smart phone.

Unlike WiCS, however, Medtronic’s bullet-shaped pacemaker, about the size of an antibiotic pill, would be delivered directly into a patient’s right ventricle through a catheter, without surgery. Unfortunately, as currently designed, the Medtronic device could not be repositioned or retrieved from the heart after its seven-year battery failed. It would remain in the heart to be replaced by a new miniature pacemaker.


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