Ophthalmology Archive

Thursday, February 4, 2010

Technology Behind Second Sight Retinal Prosthesis

Lawrence Livermore National Lab (LLNL) is touting its role in the development of the 60 electrode artificial retinal prosthesis, now being trialed by Second Sight of Sylmar, CA. The device is manufactured in batches of 12 on specialty developed wafers. LLNL produced a fascinating video showing their lab that is working on the prosthesis.

Researchers at Lawrence Livermore are today using advanced polymer-based micro-fabrication methods to further develop a biocompatible microelectrode array for the third-generation artificial retina device.

The LLNL team contributes three major components to the artificial retina: the thin-film electrode array that contains the neural electrodes; the biocompatible electronics package that contains the electronics for stimulating the retina and wireless power and communications; and an ocular surgical tool that will enable the insertion, attachment, and re-insertion of the thin-film electrode array.

The second-generation device represents a substantial performance improvement over the first-generation device in speed of recognition and resolution. Objects can now be recognized within 2-3 seconds instead of the previous 15, and the device’s 60 electrodes have improved image resolution over the 16-electrode prosthesis.

The prosthesis is now of sufficient resolution to allow recognition of doors, windows, edges, low-lying branches and a basketball backboard. The goal of the DOE project is to produce a prosthesis with more than 1,000 electrodes, which would allow facial recognition.

Expertise in biomedical microsystems at Lawrence Livermore’s Center for Nano- and Microtechnology was tapped to develop a “flexible microelectrode array,” able to conform to the curved shape of the retina, without damaging the delicate retinal tissue, and to integrate electronics developed by University of California at Santa Cruz. The device serves as the interface between an electronic imaging system and the human eye, directly stimulating neurons via thin film conducting traces and electroplated electrodes.

Link: Lab plays key role in Department of Energy's artificial retina project...

Flashbacks: Second Sight Medical Retinal Prosthesis Receives FDA Approval for Clinical Trials; Second Sight Medical Retinal Prosthesis to Receive a Wider Trial

LLNL video of wafer manufacturing after the fold (direct link to Quicktime video file):

Tuesday, February 2, 2010

TrueVision Brings an Avatar-like 3D Experience into the OR

The other day your Medgadget editor spent a few hours observing Ophthalmologic surgeries in high definition 3D care of a demo by TrueVision Systems, an angel only funded company out of Santa Barbara, CA that specializes in bringing 3D into the operating room. The set up, at least initially, is most useful for instructional purposes - allowing residents and students to better observe microscopic surgery at medical schools or teaching hospitals. Those of us watching in the OR simply put on a pair of polarized 3D glasses (the same kind you used to live the luminescent life of a Navi in Avatar), and were treated to a huge 3D eye popping out of the 46" screen in exquisite detail. The operating room had the old observation technology, a tiny, 2D display right near the 3D flat panel and the quality difference made the 2D version seem laughable. It was beautiful.

Some surgeons who operate under the microscope are even starting to use TrueVision as their primary visualization device instead of the microscope. Also, the TrueVision system can integrate into current guidance technologies to bring all of the surgical visual data together onto one screen.

From the press release on guidance integration:

For the first time ever, surgeons can connect other operating room devices into one unified visualization system. TrueVision seamlessly integrates into the multi-window 3D 1080p display the various imaging modalities and guidance from other medical devices such as Alcon INFINITI, Medtronic Stealth Station, and Intuitive Surgical’s DaVinci robot. This allows the surgeon and staff to focus on one screen in the OR to view data and the surgical field of view at the same time as opposed to looking at different displays for each device.

Here's a TrueVision video of the system used during surgery:

Product Page: True Vision

Press Release: True Vision Guidance Platform...

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Monday, January 25, 2010

Electroactive Polymer Technology Used to Create Artificial Eyelid Muscle

Stroke, injury, trigeminal neuralgia, and a number of other diseases can cause problems with the blink reflex. This frustrating and debilitating condition is currently addressed by embedding a weight into the eyelid to use gravity to bring it down, or by performing a muscle transplant, which is rarely done. Because these approaches have substantial side effects, researchers from University of California Davis Medical Center and SRI International have been working on an artificial eyelid muscle mechanism. In the latest issue of Archives of Facial Plastic Surgery the team is describing the development of a electroactive polymer artificial muscle (EPAM) based system that has yet to be tried on humans, but is showing promise in the lab.

From UC Davis Health System:

Using cadavers, the surgeons inserted a sling made of muscle fascia or implantable fabric around the eye. Small titanium screws secured the eyelid sling to the small bones of the eye. The sling was attached to a battery-operated artificial muscle. The artificial muscle device and battery were into a natural hollow or fossa at the temple to disguise its presence.
Senders and Tollefson found that the force and stroke required to close the eyelid with the sling were well within the attainable range of the artificial muscle. This capability may allow the creation of a realistic and functional eyelid blink that is symmetric and synchronous with the normal, functioning blink. A similar system also could give children born with facial paralysis a smile.

The three-layered artificial muscle was developed by engineers at SRI International of Palo Alto, Calif., in the 1990s. Inside is a piece of soft acrylic or silicon layered with carbon grease. When a current is applied, electrostatic attractions causes the outer layers to pull together and squash the soft center. This motion expands the artificial muscle. The muscle contracts when the charge is removed and flattens the shape of the sling, blinking the eye. When the charge is reactivated, the muscle relaxes and the soft center reverts back to its original shape.

An implanted battery source similar to those used in cochlear implants would power the artificial muscle.

For patients who have one functioning eyelid, a sensor wire threaded over the normal eyelid could detect the natural blink impulse and fire the artificial muscle at the same time. Among patients lacking control of either eyelid, an electronic pacemaker similar to those used to regulate heartbeats could blink the eye at a steady rate, and be deactivated by a magnetic switch.

The researchers are now refining the technique on cadavers and animal modes. They estimate the technology will be available for patients within the next five years.

Abstract in Archives of Facial Plastic Surgery: Force Requirements for Artificial Muscle to Create an Eyelid Blink With Eyelid Sling

Press statement from UC Davis Health System: Artificial muscles restore ability to blink, save eyesight...

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Thursday, January 7, 2010

ForeseeHome Helps Monitor Progress of AMD Without Visiting The Clinic

Globes, Israel's business newspaper, is reporting that Notal Vision out of Tel Aviv has received FDA approval for the firm's ForeseeHome age-related macular degeneration (AMD) analysis device. Designed to be used by patients at home, the device can help monitor AMD for signs of an oncoming choroidal neovascularization (CNV). It's not clear what is the functional mechanism of the device, but ForeseeHome will require a prescription and an ophthalmologist to review the results.

Published features from the product page:

Automated, easy to use test - specifically designed for elderly people.

Home use - familiar environment reduces anxiety and increases test frequency.

Personalized test customized to specific user - higher sensitivity.

Automatic analysis - immediate alert (if needed).

Controlled environment - accurate results.

Data export - off line, in-dept analysis capabilities.

More from Globes [online]: Notal Vision gets FDA nod for AMD home diagnostic kit...

Product page: ForeseeHome...

Product design info...

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Monday, November 16, 2009

Contact Lenses Turn Dark in Response to UV Light

Researchers have been trying to coat contact lenses with light sensitive dyes to have them turn dark during bright lighting conditions. Glasses with this property have existed for decades, but the same coating methods are not applicable to contacts.

Technology Review reports on work by the Institute for Bioengineering and Nanotechnology (IBN) in Singapore to use the entire volume of the lens to contain the dye:

Conventional transition sunglasses are coated with millions of molecules of photochromic dyes, which are transparent when out of the sun. These molecules change shape when UV light hits, enabling them to absorb UV light and triggering the darkening of the lens. When UV light disappears, the molecules change back to their original shape and transparent appearance.
Few previous attempts have been made to design transition contact lenses, largely because it's difficult to apply dye coatings uniformly to the delicate, soft surface of a contact lens. Ying and her colleagues got around this by developing a contact lens that embeds dyes uniformly throughout the material. This approach allowed them to pack more dye molecules into the material, Ying says, giving the contact lens greater sensitivity to light and thus a faster response.

Researchers created the spongy nanostructure material by mixing specific combinations of water, an oil solution with monomers commonly used in contact lenses, and a novel surfactant-- a compound that encourages mixing between water and oil solutions. The resulting material is studded with tiny pores and tunnels, which can be loaded with agents such as UV-sensitive dyes.

Read on at Technology Review...

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Monday, October 19, 2009

CYCLOPS Robot Emulates Vision of People with Eye Prostheses

When scientists want to test the performance of artificial corneas, retinal implants, and other visual prostheses, they typically require patients to be outfitted with one of these devices. Caltech scientists have now developed a robot that can "wear" visual prostheses and simulate how those might perform in the real world.

CYCLOPS's camera is gimballed, which means it can emulate left-to-right and up-and-down head movements. The input from the camera runs through the onboard computing platform, which does real-time image processing. For now, however, the platform itself is moved around remotely, via a joystick. “The platform can be operated from anywhere in the world, through its wireless Internet connection,” says Tarbell [Mark Tarbell, Caltech visiting scientist --ed.].
"We have the image-processing algorithms running locally on the robot's platform—but we have to get it to the point where it has complete control of its own responses," Fink [Wolfgang Fink, visiting associate in physics at Caltech] says.

Once that's done, he adds, "we can run many, many tests without bothering the blind prosthesis carriers."

Among the things they hope to learn from such testing is how to enhance a workplace or living environment to make it more accessible to a blind person with a particular vision implant. If CYCLOPS can use computer-enhanced images from a 50-pixel array to make its way safely through a room with a chair in one corner, a sofa along the wall, and a coffee table in the middle, then there is a good chance that a blind person with a 50-pixel retinal prosthesis would be able to do the same.

The results of tests on the CYCLOPS robot should also help researchers determine whether a particular version of a prosthesis, say, or its onboard image-processing software, are even worth testing in blind persons. "We'll be coming in with a much more educated initial starting point, after which we'll be able to see how blind people work with these implants," Fink notes.

Full story from Caltech: Caltech Scientists Create Robot Surrogate for Blind Persons in Testing Visual Prostheses...

Abstract in Computer Methods and Programs in Biomedicine: CYCLOPS: A mobile robotic platform for testing and validating image processing and autonomous navigation algorithms in support of artificial vision prostheses

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Thursday, September 24, 2009

Retinal Implant Brings Terminator Like Eyes Closer to Reality

We have always had a fascination with robotic eyes, whether in RoboCop or Terminator, and we have previously covered some of the exciting developments in retinal implants. MIT is reporting that its researchers, led by Dr. John L. Wyatt, are working on a retinal implant that bypasses damaged retinal cells in order to give direct visual input to the brain.

The implant works in conjunction with a specially designed set of glasses that have an embedded camera that wirelessly transmits power and image signals to the microchip in the retina which then transmits the signals to the brain. The microchip has receiving coils that surround the eyeball, much like a natural retina. The microchip itself is sealed in a titanium case to avoid corrosion. The chip will receive visual signals from the glasses which activate the electrodes, which in turn fire nerve cells to carry visual input to the brain. The microchip will not restore vision to a perfect standing, but is intended to help a blind patients navigate.

The following is taken from an MIT press office statement:

One question that remains is what kind of vision this direct electrical stimulation actually produces. About 10 years ago, the research team started to answer that by attaching electrodes to the retinas of six blind patients for several hours.

When the electrodes were activated, patients reported seeing a small number of "clouds" or "drops of blood" in their field of vision, and the number of clouds or blood drops they reported corresponded to the number of electrodes that were stimulated. When there was no stimulus, patients accurately reported seeing nothing. Those tests confirmed that retinal stimulation can produce some kind of organized vision in blind patients, though further testing is needed to determine how useful that vision can be.

After those initial tests, with grants from the Boston Veteran's Administration Medical Center and the National Institutes of Health, the researchers started to build an implantable chip, which would allow them to do more long-term tests. Their goal is to produce a chip that can be implanted for at least 10 years.

One of the biggest challenges the researchers face is designing a surgical procedure and implant that won't damage the eye. In their initial prototypes, the electrodes were attached directly atop the retina from inside the eye, which carries more risk of damaging the delicate retina. In the latest version, described in the October issue of IEEE Transactions on Biomedical Engineering, the implant is attached to the outside of the eye, and the electrodes are implanted behind the retina...

While they have not yet begun any long-term tests on humans, the researchers have tested the device in Yucatan miniature pigs, which have roughly the same size eyeballs as humans. Those tests are only meant to determine whether the implants remain functional and safe and are not designed to observe whether the pigs respond to stimuli to their optic nerves.

So far, the prototypes have been successfully implanted in pigs for up to 10 months, but further safety refinements need to be made before clinical trials in humans can begin.

Press release: Stimulating sight...

MIT Research Lab: Retinal Implant Research Group...

Flashback : Experimental Bionic Eyes Give Hope to Totally Blind

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Wednesday, September 2, 2009

Prescriptionless Glasses to Offer Eyesight for Third World

Optometry services are expensive and hard to find in the developing world, which means a good part of the world's population simply has no access to prescription eye glasses. Josh Silver, an atomic physicist, has developed liquid filled glasses, worth only $19, that the patient himself can set. Here's a talk he gave at TED discussing and demonstrating the technology:

Link @ TED: Josh Silver demos adjustable liquid-filled eyeglasses

Flashback: TruFocals Offer New Option For Presbyopic Eyes

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Tuesday, September 1, 2009

Electronic Contact Lenses Promise Future of Advanced Augmented Vision

Babak A. Parviz, an associate professor at the University of Washington whose research was seen on our pages before, wrote an article for IEEE Spectrum discussing the work of his team to develop electronic contact lenses to provide continuous monitoring of glucose, augmented vision, and potential other implications of the technology. Parviz also gives a rundown of the challenges involved in creating functional in-lens displays that users can focus on at such a short distance.

From the article:

The glucose detectors we’re evaluating now are a mere glimmer of what will be possible in the next 5 to 10 years. Contact lenses are worn daily by more than a hundred million people, and they are one of the only disposable, mass-market products that remain in contact, through fluids, with the interior of the body for an extended period of time. When you get a blood test, your doctor is probably measuring many of the same biomarkers that are found in the live cells on the surface of your eye—and in concentrations that correlate closely with the levels in your bloodstream. An appropriately configured contact lens could monitor cholesterol, sodium, and potassium levels, to name a few potential targets. Coupled with a wireless data transmitter, the lens could relay information to medics or nurses instantly, without needles or laboratory chemistry, and with a much lower chance of mix-ups.
Three fundamental challenges stand in the way of building a multipurpose contact lens. First, the processes for making many of the lens’s parts and subsystems are incompatible with one another and with the fragile polymer of the lens. To get around this problem, my colleagues and I make all our devices from scratch. To fabricate the components for silicon circuits and LEDs, we use high temperatures and corrosive chemicals, which means we can’t manufacture them directly onto a lens. That leads to the second challenge, which is that all the key components of the lens need to be miniaturized and integrated onto about 1.5 square centimeters of a flexible, transparent polymer. We haven’t fully solved that problem yet, but we have so far developed our own specialized assembly process, which enables us to integrate several different kinds of components onto a lens. Last but not least, the whole contraption needs to be completely safe for the eye. Take an LED, for example. Most red LEDs are made of aluminum gallium arsenide, which is toxic. So before an LED can go into the eye, it must be enveloped in a biocompatible substance.

Link @ IEEE Spectrum: Augmented Reality in a Contact Lens...

Side image: One lens prototype [top] has several interconnects, single-crystal silicon components, and compound-semiconductor components embedded within. Another sample lens [bottom] contains a radio chip, an antenna, and a red LED

Flashback: Electronic Contact Lenses for Better Vision

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Monday, August 10, 2009

TruFocals Offer New Option For Presbyopic Eyes

Dr. Stephen Kurtin, an inventor and a physicist with a degree from Caltech, has been working on adjustable eye glasses for the last two decades, trying to overcome the disadvantages of bifocals and progressive lenses. His work has finally led to a commercial product, called TruFocals, which features a slider above the nose bridge that changes the focal point of the lenses in real time. The glasses use a conventional lens co-axially paired with a distensible membrane, and a clear liquid resides between the two. The shape of the liquid can be adjusted precisely via the slider activated membrane, providing a selectable focal range that you can change depending on what you're looking at.

Here's Stephen Kurtin presenting the TruFocals:

Product page: TruFocals...

Review of TruFocals by John Markoff at the New York Times...

Flashback: Water Power in Developing World to Cure Poor Eyesight

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Wednesday, August 5, 2009

SENSIMED Triggerfish Electronic Contact Lens Provides Continuous Monitoring of Intraocular Pressure

Mass Device has interviewed the CEO of SENSIMED AG, a company out of Lausanne, Switzerland that has developed a contact lens capable of continuously measuring intraocular pressure. The lens is composed of a strain gauge and a microchip to process the data off the instrument. The patient also wears an antenna array around the eye socket that powers the lens and reads the information coming off the microchip. Clinicians can then assess an entire day's worth of patient's intraocular pressure back at the clinic. We've written about the development of the contact lens before, but we must have missed last February's European approval of the SENSIMED Triggerfish® system.

Triggerfish system components:

Sensor: Soft, hydrophilic silicone disposable contact lens embedding a MEMS sensor and a telemetry microprocessor. The sensor comes in three different base curves. All elements embedded in the lens are excentric, out of the line of sight.

Antenna and datacable: A circular antenna taped around the eye which sends energy to the sensor and receives the measurement information. The antenna is connected to the portable recorder through a thin flexible datacable.

Recorder: A battery powered recorder which will store measurement information and wirelessly upload this information on the ophthalmologist's computer at the end of the monitoring session.

Software: The software running on the ophthalmologist's computer to retrieve and to visualize the intraocular pressure profile.

Product page: SENSIMED Triggerfish...

Link: Mass Device interview with CEO of Sensimed AG...

Flashbacks: Sensimed Technology: Noninvasive Intraocular Pressure Monitoring with a Contact Lens; Pressure Sensing Contact Lenses May Provide Continuous Glaucoma Monitoring

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Thursday, April 2, 2009

Implantable Telescope for AMD Expects FDA Approval

VisionCare Inc., now out of Saratoga, California, is reporting that the "FDA Ophthalmic Devices Advisory Panel unanimously recommended that the FDA approve, with conditions, the premarket application (PMA) for its implantable telescope for End-Stage AMD." We have been reporting about this device, designed for advanced macular degeneration, since 2005 when it was in Phase II/III clinical trials. The fresh news will probably pave way for bionic geriatrics in the next few years.

From the product page:

The prosthetic telescope, together with the cornea, acts as a telephoto system to enlarge images 3X or 2.2X, depending on the device model used. The telephoto effect allows images in the central visual field ('straight ahead vision') to not be focused directly on the damaged macula, but over other healthy areas of the central and peripheral retina. This generally helps reduce the 'blind spot' impairing vision in patients with AMD, hopefully improving their ability to recognize images that were either difficult or impossible to see.

The prosthetic telescope is implanted by an ophthalmic surgeon in an outpatient surgical procedure. The device is implanted in one eye, which provides central vision as described above, while the non-implanted eye provides peripheral vision for mobility and navigation. After the surgical procedure, the patient participates in a structured vision rehabilitation program to maximize their ability to perform daily activities. Situated in the eye, the device allows patients to use natural eye movements to scan the environment and reading materials.

Press release: FDA Advisory Panel Recommends Approval of VisionCare's Implantable Telescope for End-Stage Macular Degeneration

VisionCare technology page...

Flashbacks: VisionCare's Micro-telescope Prosthesis Close to FDA Approval; The Implantable Miniature Telescope...

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Thursday, March 19, 2009

Cardinal's Endura Scrubs for the Modern Clinician

Cardinal Health is releasing a new line of clinical scrubs that the company believes will make your life safer, easier, and more comfortable. The big deal about Cardinal's Endura™ apparel line is the specialty fabric used, which is supposedly stronger and more breathable.

Some features from the product page:

Excess moisture is wicked away from your skin to keep you dry and cool, no matter what you’re doing.

Scrubs shouldn't leave you feeling restricted or confined. Endura™ scrubs move with your body and help maximize your gait and pace. In addition, the Maximum-Motion™ sleeve allows your shirt to stay tucked in even when you reach and stretch.

Our advanced, synthetic material is breathable, flexible and helps control your heat index and perspiration.

Our scrubs offer a shirt pocket and two side flanking pant pockets to tuck away the important things you want to keep close. The deep side pockets in our pants are angled to keep items in, whether you're sitting or standing.

The smooth fabric of Endura™ scrubs feels natural and soft on the skin.

People aren’t rectangular. So instead of making our scrubs rectangular, we looked at the actual dimensions of thousands of healthcare workers. The cut of our scrubs follows the natural line of your body and gets rid of the bulky feel and appearance of traditional scrubs.

A unique snap system allows you to customize pants length and avoid tripping, falling or slipping. Elastic on the waistband, in addition to a drawstring, helps position pants where you want them.

Strategically placed ventilation zones across the middle of the back and behind the knee keep you dry and comfortable.

Even after 90 washes, EnduraT scrubs are still going strong. Stronger than a brand-new pair of the top-selling traditional scrubs, in fact*. You'll also notice minimal color loss and lasting moisture-wicking abilities. The competitor's scrubs, on the other hand, typically only last 50 washes.

The top-selling traditional scrubs lose 15% lint when abraded. EnduraT scrubs lose only 1.4%, making them the lowest linting scrub on the market.

Made of the strongest material on the market, EnduraT scrubs outlast the competition. Our advanced, synthetic material is abrasion- and tear-resistant and has the most uniform strength in both directions.

EnduraT scrubs can be washed at cooler temperatures and dry faster than traditional scrubs. This requires less energy and can result in savings to your hospital.

Product page: Endura™ Performance Apparel

Press release: Cardinal Health launches new products for the operating room

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Thursday, March 5, 2009

Experimental Bionic Eyes Give Hope to Totally Blind

Three blind patients at the UK's Moorfield eye hospital have been fitted with a bionic vision system from 2nd Sight Medical . The system, covered by us previously, captures light in a video camera, and wirelessly sends it to an electrode implanted in the eye. One of the patients the BBC spoke to is reporting seeing basic light signals.

Here's an explanation of the system from BBC:

Monday, February 23, 2009

RETISERT Eye Implant Prevents Lost Vision

Sympathetic ophthalmia is an autoimmune condition thought to be caused when one eye is severely damaged, and the immune system overreacts and attacks the healthy eye, often leading to complete blindness. Until recently the common treatment option was oral steroids and immunosuppressive medication, but now clinicians at the University of Iowa are using a steroid releasing implant from Bausch & Lomb to prevent such a form of blindness.

University of Iowa reports:

The new Retisert treatment involves the surgical implantation into the endangered eye of a small plastic tab that contains a slow-release steroid called fluocinoloe acetonide. The insert provides immunosuppression only to the endangered eye, not other body parts. It lasts for about two-and-a-half years and then can be replaced.

Along with UI retinal surgeons James Folk, M.D., professor of ophthalmology, and Karen Gehrs, M.D., clinical associate professor of ophthalmology, Mahajan published a retrospective paper online in January in the journal Ophthalmology that documents the successful use of Retisert to treat eight patients with sympathetic ophthalmia.

The device previously was studied in approximately 300 individuals who had a different immune system inflammation of the eye. The UI-led sympathetic ophthalmia study found that with Retisert, the eight patients reduced or eliminated use of systemic medications to control inflammation. While two patients needed to resume using an oral immunosuppressive, vision improved or remained stable in all eight patients.

"Using Retisert, we are stabilizing vision in patients with sympathetic ophthalmia and getting them off the heavy-duty immunosuppressive medications," Mahajan said. "Patients had been willing to put up with the serious side effects of systemic immunosuppression because if they lost vision in their remaining good eye, it would be totally life-altering. With Retisert, we can save the eye, and the side effects are limited to treatable risks of high pressure or cataracts in the eye."

While each implant costs approximately $20,000, their use appears to be less expensive over the long run compared to systemic immunosuppressive drugs and the required frequent hospital visits.

"If you add up the total number of patient visits, costs of lab tests and the costs of the immunosuppressive drugs, the $20,000 for the device is cheaper," Mahajan said.

Press release: New surgical implant tested at UI prevents total blindness

Product page: RETISERT

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Tuesday, January 6, 2009

Water Power in Developing World to Cure Poor Eyesight

An Oxford University physics professor Dr. J D Silver has developed water filled glasses that have a variable optical strength thanks to a small pump dial. The idea is that the services of an optician would not be needed since "the wearer can adjust the power of each lens to his or her own requirements."

From the technology page at Adaptive Eyecare, the manufacturer of the device:

The approach of Adaptive Eyecare has been to develop a completely new ophthalmic lens technology which permits us to manufacture revolutionary new spectacles which are universal, in the sense that one pair may be used to correct the vision of over 90% of people requiring correction. The special feature is that the wearer can adjust the power of each lens to his or her own requirements - this is particularly useful for developing world populations in areas which do not have adequate numbers of those specially trained personnel normally associated with the provision of vision correction.

The lenses in Adaptive Eyecare's spectacles operate in a manner which is somewhat similar in its optical function to the crystalline lens in the human eye - our lenses have the feature that the curvature of the lens surfaces is under the control of the wearer of the spectacles, and a simple manual adjustment is all that is needed to vary the power of each lens. In use, the wearer adjusts each lens so as to get clearest vision. This process takes less than a minute for both eyes. Having found the best setting, the lenses are then set, and the ancillary device used for lens adjustment is removed and discarded.

Adaptive Eyecare's adaptive lenses are fluid- filled and the power is changed by varying the amount of fluid in the lens. The power range of our lenses is +6 to -6 Dioptres, and the optical quality is similar to that of the typical human eye.

Of course, we'd like to see the quality that glasses made of stretchable membranes and liquid water can provide. They, obviously, can't be all bad if 30,000 have already been distributed.

Friday, December 12, 2008

FDA Approves Compassionate Use of Investigational Treatment for AMD

The FDA has given compassionate approval to use NeoVista's Epiretinal Brachytherapy (a procedure that is presently in Phase III studies) to treat a woman's wet-AMD (age-related macular degeneration). The company hopes that its NeoVista Epi-Rad 90™ Ophthalmic System one day will become a therapeutic option for patients with wet-AMD. John N. Hendrick, President and CEO of NeoVista says, "Even though this patient has not benefited from currently approved therapies, our hope is that she will benefit from our treatment as a final effort to avoid complete loss of vision."

From a NeoVista, Inc. press release:

The patient received NeoVista's therapy ... in Nashville, Tenn.; the procedure was performed by Dr. Carl Awh, President of Tennessee Retina, and an investigator in NeoVista's ongoing Phase III study, CABERNET (CNV Secondary to AMD Treated with BEta RadiatioN Epiretinal Therapy).
The patient suffered from advanced wet AMD in both eyes and had not benefited from any available treatment, including anti-vascular endothelial growth factor (anti-VEGF) agents, the current standard of care for wet AMD. The patient's left eye had progressively worsened despite treatment with photodynamic therapy and intravitreal steroids prior to the advent of anti-VEFG therapy, as well as later injections of anti-VEGF agents. Her right eye was following a parallel course, with advanced vision loss due to an enlarging exudative retinal detachment caused by wet AMD. Because of the similarity in the appearance of the two eyes and the failure of prior therapies to successfully treat the left eye, a decision was made to treat the patient's right eye with NeoVista's therapy...

NeoVista's novel therapy applies a targeted dose of beta radiation to the abnormal leaking blood vessels that affect central vision in patients with wet AMD. Preliminary data show that NeoVista's targeted radiation therapy can be safe for both the patient and the physician, and may be able to improve patient's vision. The current standard of care for wet AMD requires monthly injections of anti-VEGF drugs into the eye for an indefinite period of time.

In contrast to other forms of radiation therapy for wet AMD, NeoVista's approach delivers the peak dose of energy directly to the lesion without damaging the normal retinal vasculature. Utilizing strontium 90, the focused energy is delivered to a target area up to 3 mm in depth and up to 5.4 mm in diameter. Importantly for patients, the systemic exposure to radiation is minimal, as the effective dose to the entire body from NeoVista's epiretinal device is less than that from a typical chest x-ray.

To understand how the system works, please take a look at the video distributed by the company to the media:

Wednesday, December 10, 2008

TEFI Endoscopic Technology Watches Changes in Retina

Researchers at the University of Bristol have developed a new diagnostic modality to monitor the retina, a technique that produces high resolution color images like the ones above.

Using the new technique called ‘TEFI’ (Topical Endoscopic Fundal Imaging), Professor Andrew Dick, David Copland and the team from the University of Bristol’s Academic Unit of Ophthalmology, monitored changes in mice retina over time, without distress to the animals or the need for anesthesia.
The study focused on a condition in mice similar to human posterior uveitis, an inflammation that affects the back of the eye and which can be difficult to monitor using existing techniques. TEFI allowed the researchers to see changes to the eye that were previously undetectable.

“TEFI enhances our monitoring of clinical disease in a rapid and non-invasive fashion,” Copland said. “It will aid in the design of experimental protocols according to clinical observations.”

Professor Dick added: “Combined TEFI and histological methods enable the observation of clinical features and severity of disease, but information regarding the dynamics, phenotype, function and quantity of cellular traffic through the eye is only provided through detailed analysis of cell populations present in the eye at various stages of disease progression.”

The study, “The Clinical Time-Course of Experimental Autoimmune Uveoretinitis Using Topical Endoscopic Fundal Imaging with Histologic and Cellular Infiltrate Correlation,” was published this week in Investigative Ophthalmology and Visual Science. It featured the use of Topical Endoscopic Fundal Imaging (TEFI), a technique that uses an endoscope with parallel illumination and observation channels connected to a digital camera.

Press release: New monitor for eye disease ...

Full article in Investigative Ophthalmology and Visual Science

Story @ The Engineer Online: Vision monitor...

Image: Clinical observations of EAU (Experimental Autoimmune Uveoretinitis) in B10.RIII mice using topical endoscopic fundus imaging. Shown are examples of clinical disease observed in a representative cohort of B10.RIII mice immunized for EAU using RBP-3161-180 in CFA. Images show raised and swollen optic nerve, with typical perivascular cuffing and caliber changes to vessels (arrowhead, A), and an inferior exudative retinal detachment (B), at day 20 pi. Images including the ciliary body demonstrate peripheral chorioretinal inflammation and inflammatory vascular changes of the marginal vein (C, D). Scattered flecks which correlate to histologic features of retinal folds, are typically observed after day 15 pi (E). Multiple choroidal lesions (arrowhead) associated with inflammatory vascular changes (perivascular cuffing) and swollen optic nerve persisted at day 28 pi (F).

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Monday, November 24, 2008

Australian Institutes Team to Develop Bionic Eye

A group of Australian institutions, including the University of Melbourne, the University of New South Wales, the Bionic Ear Institute, Centre for Eye Research Australia and the Victoria Research Laboratory of NICTA, are joining forces to work together on creating a functional bionic eye that would restore vision to those with degenerative or inherited eye disease.

The new consortium, called Bionic Vision Australia, reports:

A bionic eye will assist in restoring patient mobility, independence and quality of life by effectively replacing the function of damaged light-sensing cells in the eye. While the clarity and definition of vision will not be equal to normal sight, the device will allow patients to move around, detect large objects and, in time, read text and recognise faces and emotions.
Bionic Vision Australia has submitted a detailed plan and funding request to the Australian Government to enable it to undertake the required research and early clinical testing. The New South Wales and Victoria governments have both provided support to the partnership to enable the development of the detailed plan.

The proposal follows an 18-month feasibility study undertaken by members of the consortium and heightened public interest in the bionic eye, most notably at the recent Australia 2020 Summit where it was flagged as a "big idea" worthy of consideration for Australia to pursue.

Bionic Vision Australia proposes to have a first advanced prototype ready for the first human implant by early 2012 that delivers significant benefits to patients with severe mobility and light perception difficulties. This device is the result of research undertaken over a 10-year period by the Australian Vision Prosthesis Group at the University of New South Wales. An enhanced second prototype developed at the Victoria Research Laboratory of NICTA could be available for the first human implant by late 2013 and would provide further improved quality of life for patients where image perception is the primary consideration.

Video from University of New South Wales:

Press release: Research "A" team to fast track Bionic Eye - Australian consortium announced today ...

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