Category: Implants and Prostheses

Common Eye Ointment can Damage Glaucoma Implants, Study Warns

Research shows that petrolatum-based eye ointments can cause the device to swell and potentially rupture, prompting an urgent update to clinical guidance.

Photo by Tima Miroshnichenko


Widely-used eye ointments can cause glaucoma implants to swell and potentially rupture, according to new research from Nagoya University in Japan. This study is the first to show, using clinical and experimental evidence, that petrolatum-based eye ointments can compromise the PRESERFLO® MicroShunt, an implant used in over 60 countries to treat glaucoma.

Glaucoma is an eye disease that damages the optic nerve and can lead to vision loss. It often results from increased intraocular pressure caused by blocked drainage of eye fluid. A recent study estimated that 76 million people globally are affected by glaucoma.

Progression of visual field loss (from left to right) due to glaucoma
(Credit: Ryo Tomita)

MicroShunt is a small filtration device implanted in the eye to improve fluid drainage in glaucoma patients. Compared to traditional surgeries, it lowers post-operative complications and reduces reliance on additional medications.

MicroShunt is made from a styrenic thermoplastic elastomer based on a polystyrene-block-polyisobutylene-block-polystyrene (SIBS) block polymer, which is highly biocompatible, flexible, and less likely to cause inflammation or scarring. However, this material is vulnerable when it comes into contact with hydrocarbon- and oil-based materials. Due to its high oil affinity, exposure to petrolatum-based eye ointments may allow oil components to penetrate the device, causing swelling and potential changes in its shape and flexibility.

The MicroShunt manufacturer’s instructions state that “the MicroShunt should not be subjected to direct contact with petrolatum-based (ie, petrolatum jelly) materials, such as ointments and dispersions.” But this precaution is not widely recognised or consistently followed in clinical practice.

“Swollen MicroShunts can be structurally fragile,” said ophthalmologist and Assistant Professor Ryo Tomita of Nagoya University Graduate School of Medicine, the study’s first author. “During surgery, I observed a rupture in a swollen MicroShunt. If more clinicians are aware of this risk, they will be able to prevent similar problems.”

Tomita and colleagues, including Assistant Professor Taiga Inooka and Associate Professor Kenya Yuki from Nagoya University Hospital and the Graduate School of Medicine collaborated with Dr. Takato Kajita and Junior Associate Professor Atsushi Noro from the Graduate School of Engineering to examine changes in the MicroShunt after exposure to a petrolatum-based eye ointment.

The medical team reviewed clinical cases, while the engineering team conducted laboratory analyses. The findings were published in Graefe’s Archive for Clinical and Experimental Ophthalmology.

Clinical evidence

The clinical study examined seven glaucoma patients whose MicroShunt implants were later removed for different reasons. The results revealed a clear pattern. In three cases, the MicroShunt was exposed outside the conjunctiva, and patients received a petrolatum-based eye ointment. All three explanted devices showed significant swelling, and two of them ruptured.

In three other cases, the MicroShunt remained covered by the conjunctiva, and no ointment was administered. These devices retained their original structure. Crucially, in one additional case, the MicroShunt was exposed outside the conjunctiva, but no ointment was applied. The device did not swell. This indicates that direct contact with the ointment, rather than conjunctival rupture alone, is the primary cause of swelling.

Photographic comparison of MicroShunt illustrating size changes
Top: MicroShunt explanted from a patient, exhibiting diffuse swelling with fracture and loss of one fin
Middle: MicroShunt explanted from another patient, showing localized swelling around the fin
Bottom: Unused MicroShunt (control)

Scale: 1 division = 1 mm   
(Credit: Ryo Tomita)

Laboratory confirmation

Laboratory experiments confirmed the clinical findings. The team immersed unused MicroShunts in petrolatum-based eye ointment to reproduce the swelling seen in clinical cases. Microscopic measurements showed significant changes. After 24 hours in the ointment, the MicroShunt’s outer diameter increased to 1.44 times its original size, and the fin-like portion widened to 1.29 times its initial value.

Chemical analysis identified the cause of this change. After 24 hours of immersion, oil components made up approximately 45% of the MicroShunt’s total weight, rising to 73% after three months. These results confirmed the primary cause of swelling to be the absorption of oil-based ointment constituents into the material.

Clinical implications

The research team emphasises that clinicians should avoid using petrolatum-based ointments on patients with MicroShunt implants, particularly when the device is exposed outside the conjunctiva. Alternative post-operative treatments should be considered, while further research is needed to assess whether swelling impacts MicroShunt performance even when rupture does not occur.

“Our study found that commonly used medical materials can cause unexpected complications if their chemical properties and usage environments are not fully understood,” Noro stated. “From both medical and engineering perspectives, we emphasise the importance of understanding the chemical properties of medical materials and appropriately managing their usage environments.”

Paper information:

Ryo Tomita, Taiga Inooka, Takato Kajita, Hideyuki Shimizu, Ayana Suzumura, Jun Takeuchi, Tsuyoshi Matsuno, Hidekazu Inami, Koji M. Nishiguchi, Atsushi Noro, and Kenya Yuki. (2026) Petrolatum-based ointment application induces swelling of the PRESERFLO MicroShunt. Graefe’s Archive for Clinical and Experimental Ophthalmology
DOI: 10.1007/s00417-025-07075-2

Össur South Africa Launches 2026 ‘What’s Your Epic?’ Campaign

Movement is a Right, not a Privilege

Inspiring South Africa to Support Mobility, Inclusion and the Power of Possibility

Össur South Africa‘s Team 1: Rentia Retief & Travis Warwick-Oliver

Össur South Africa is proud to announce the launch of the 2026 ‘What’s Your Epic?’ campaign, an initiative that champions one simple truth: everyone deserves the freedom to move. As the world turns its attention to the Cape Epic from 15 – 22 March 2026, Össur is once again harnessing this global stage to drive awareness, spark action, and rally support for mobility access across South Africa.

Following the success of last year’s inaugural campaign, Össur South Africa has entered three amputee teams into the 2026 Cape Epic, one of the world’s most iconic and demanding mountain biking events. These six remarkable riders embody grit, courage, and the unbreakable belief that mobility transforms lives. Their mission is bigger than the race: to unlock meaningful support and funding for three exceptional non-profit organisations: Jumping Kids, Zimele and Rejuvenate SA.

“Movement is a fundamental right, not a privilege reserved for the few,” says Blignaut Knoetze, Managing Director of Össur South Africa. “Whether you’re an elite athlete, a child receiving their first prosthetic or an adult rebuilding independence; mobility unlocks dignity, participation, and potential. ‘What’s Your Epic?’ is our call to South Africa to stand with us in supporting organisations who make this freedom possible.”

The 2026 campaign aims to raise funds and awareness for four organisations driving mobility access and inclusion:

  • Jumping Kids: Providing quality prostheses, education access, and sport opportunities to children living with limb loss, giving them the tools to build confident, successful futures.
  • Rejuvenate SA: Founded on the belief that movement is a basic human right, Rejuvenate SA supplies mobility aids to those who cannot afford them, restoring dignity and independence.
  • Zimele: Meaning “independence” in Xhosa, Zimele supports adults with physical disabilities to regain control over their lives, reintegrate into society and build economic self-sufficiency.

Together, these six athletes across three teams are redefining what’s possible.

  • Team 1: Rentia Retief & Travis Warwick-Oliver

Rentia (33, Somerset West), an artist and amputee athlete, who survived a cycling accident in 2023. Her journey is a testament to courage and the belief that mobility is a right every person deserves. Partnering with her is Travis (32, Durban), founder of Rejuvenate SA, adaptive athlete, and two-time UTMB finisher who has transformed his own amputation into a mission to help others move freely and live without limitations.

  • Team 2: Mhlengi Gwala & Kean Dry

Mhlengi (34, Durban), an international para-triathlete and multiple African champion who continues to defy all odds after a 2018 attack that led to the amputation of his right leg. Riding alongside him is Kean (30, Cape Town), a dedicated endurance athlete and community motivator whose story of resilience inspires thousands to believe that adversity does not define possibility.

  • Team 3: Brian Style & Rudi Joubert

Brian (40, Springs), a passionate cyclist who has rebuilt his life through mountain biking, uses sport as a platform for giving back. He rides with Rudi (42, Secunda), a determined amputee athlete known for his positivity, teamwork, and commitment to raising funds for mobility solutions.

“These riders are not just racing, they are raising their voices for those who cannot and shining a spotlight on organisations that restore dignity, independence, and hope,” says Knoetze. Össur South Africa is inviting the public, corporates, partners, and communities to be part of this extraordinary movement. Whether through donations, corporate partnerships, fundraising initiatives, or simply sharing the message, every contribution helps someone stand, walk, run, play, work, or dream again.

“‘What’s Your Epic?’ is about pushing boundaries; not just on the bike, but in society,” adds Knoetze. “When we support mobility, we support access. We support inclusion. We support futures. We are asking South Africa to back our riders, our NPOs, and the belief that everyone deserves the freedom to move.”

Donate, fundraise, or get involved as an individual and/ or company. Your support can help someone take their first step, return to work, join a sport, or believe in possibility again.
Össur Donations, ABSA Bank, Account number: 4123 215 542, Branch code: 632005
Reference: company name and contact number

Please contact Amelda Potgieter (apotgieter@ossur.com) for more information and/ or Section 18A certificates.

This is more than a race. It’s a movement. What’s your Epic?

‘It’s a great sign’: Innovative Cochlear Implant Trial Expands Earlier than Expected

The new cochlear implant is implanted invisibly under the skin, unlike this standard design. Photo by Brett Sayles

A highly sought-after clinical trial testing completely under-the-skin cochlear implants is expanding earlier than expected. Promising preliminary results showed no serious adverse events or unexpected device effects.

The Medical University of South Carolina, which has one of the larger cochlear implant programmes in the country, is one of several sites in the United States taking part in the Acclaim study. Three patients were implanted in the first wave of the trial and have been using their devices for at least six months. Now, MUSC has the chance to enrol more.

“New patients are coming this week, and we’re going to resume device placement as soon as possible. We have people flying in from all over the country to be part of the trial as well as South Carolinians,” said Teddy McRackan, MD He’s medical director of the MUSC Health Cochlear Implant Program.

Some participants are traveling to Charleston to get the experimental implants because slots in the 56-person national trial are limited, and they like the idea of cochlear implants without external parts.

The Acclaim implants would be the first such devices to hit the market if they obtain approval from the Food and Drug Administration. McRackan said they use the body’s natural hearing bone movements to detect sound instead of the external microphones used in traditional cochlear implants.

“The trial has made it clear that hidden cochlear implants appeal to a lot of people,” said audiologist Elizabeth Camposeo, AuD. She’s assistant director of the MUSC Health Cochlear Implant Program.

“Seeing our patients going through this trial just feels like such a massive opportunity. I didn’t know how hard we were struggling to overcome the physical stigma of visible implants. There were many patients we screened for the trial who we could help with a traditional implant but who did not want any part of it. These people are profoundly hearing impaired, like 10 out of 10 terrible hearing, and they absolutely would not consider a traditional implant.”

They have plenty of company. Just 5% of adults in the United States who could hear better with traditional cochlear implants have them, according to the American Cochlear Implant Alliance.

To measure the Acclaim implants’ effectiveness, participants will check in for testing at one month, three months, six months, one year and two years after their implants are activated. Implantation requires surgery and then one month for healing before doctors turn on the devices.

Once the implants are activated, Camposeo said researchers will start analysing data about how much sound they detect and how well patients understand speech. “Similar to when you have your eyes checked, how close are you to 20/20 vision, we check sound detection. More importantly, we test speech understanding. We play a word. You repeat it back. We play a sentence. You repeat it back in both quiet and noise, because the world is a noisy place.”

A noisy place, and a place where potentially groundbreaking devices can be developed quickly, McRackan said. “I don’t think anybody thought two years ago that the Acclaim device would be at this point now. I think it’s kind of amazing how fast things are progressing.”

Source: Medical University of Southern Carolina

Prosthetic Designers Take Top Awards at the Entrepreneurship Intervarsity 2025

A young man’s determination to help the thousands of South Africans who cannot afford a quality prosthetic spurred him into action. It led him to design a pneumatic-actuated prosthetic foot, winning him the title of 2025 EDHE Studentpreneur of the Year at the seventh annual EDHE Entrepreneurship Intervarsity.

Mr Zanodumo Godlimpi, a postgraduate student at Walter Sisulu University, won R120 000 in overall prize money and a further R25 000 for another win in the Academic Research Commercialisation category.

A fellow prosthetic designer and innovator – Ms Amohetsoe Shale from Stellenbosch University – was named Top Student Womanpreneur, winning R25 000. Her company, Navu, designs and produces cost-effective, high-performance assistive technologies, beginning with a passive polycentric prosthetic knee. Ms Shale emerged a runner-up in the Academic Research Commercialisation category.

Below is the breakdown of the 2025 EDHE Entrepreneurship Intervarsity Award winners:

The EDHE Studentpreneur of the Year

·     Zanodumo Godlimpi (Walter Sisulu University), founder of a pneumatic-actuated and affordable prosthetic foot. (R120 000).

Top Student Womanpreneur

·     Ms Amohetsoe Shale (Stellenbosch University) founder of the NAVU Group, who design affordable, high-performing prosthetic knees for amputees. (R25 000).

Existing Business – Tech

·     Winner: Ms Kholofelo Makhubupetsi (University of Mpumalanga), co-founder of CSK Environmental Consulting which guides businesses towards sustainable practices while leveraging government grants. It helps organisations reduce greenhouse gas emissions and conserve biodiversity (R25 000).

·     Runners-up: Ms Khanyisa Mokgolobotho and Ms Rosemary Erawemen (Stellenbosch University), co-founders of Techmed Connect, a company revolutionising South African healthcare with technology through innovative AI solutions and helping bridge language gaps (R10 000).

Existing Business – Social Impact

·     Winner: Ms Malehu Mohale (University of Cape Town), founder of the Early Bird Testimony Academy, an online tutoring and mentorship platform. (R25 000).

·     Runner-up: Mr Kabelo Makhetha (Central University of Technology), founder of OWA Jewellers which creates jewellery that blends African design with safety technology, making it a potential life-saving tool for individuals with conditions like epilepsy or dementia. (R10 000).

·     2nd runner-up: Mr Katleho Mphutlane (University of Fort Hare), co-founder of Incremental Education which seeks to bridge the gap between education and employability and empowers students with practical skills and global opportunities, focusing on supporting TVET college and university of technology students in tourism, hospitality and agriculture. (R10 000)

Existing Business – General

·     Winner: Mr Tumelo Ratala (University of South Africa), founder of Drink & Print which offers purified water and printing services (R25 000).

·     Runner-up: Mr Thando Mzimela (University of Cape Town), co-founder of uniMark by TM Agrichem that connects university students with essential services through an online platform that streamlines access to local businesses (R10 000).

Academic Research Commercialisation

·     Winner: Zanodumo Godlimpi (Walter Sisulu University), founder of a pneumatic-actuated and affordable prosthetic foot. (R25 000).

·     Runner-up: Ms Amohetsoe Shale (Stellenbosch University) founder of the NAVU Group who designs affordable, high-performing prosthetic knees for amputees. (R10 000).

The Entrepreneurship Development in Higher Education (EDHE), a programme of the Department of Higher Education and Training (DHET) administered and implemented by Universities South Africa (USAf), is the custodian of the annual EDHE Entrepreneurship Intervarsity. EDHE is predominantly funded through the University Capacity Development Programme (UCDP) of the DHET.  

The Intervarsity is a platform designed to identify, recognise and celebrate top student entrepreneurs at South Africa’s 26 public universities. The event has, over the years, enjoyed the support of numerous private sector entities, including the Allan Gray Foundation, the Entrepreneurs’ Organisation and the SAB Foundation, which, in 2025, supports the initiative for the sixth year in a row.

Mr Phillip Tshabalala, Chief Director: Teaching, Learning and Research Development in the Department of Higher Education and Training, delivered the keynote address during the award ceremony.  Labelling the event both timely and significant, he said it represented an important step forward in collective efforts to advance entrepreneurial universities.

Referencing the recent G20 Summit and its commitment to boost inclusive growth — with a strong focus on Africa and the broader Global South – he said: “Universities play a vital role in preparing students, not only to participate in the labour market as employees, but also to serve as future employers, industrialists, innovators and leaders. DHET works closely with universities, USAf and other key partners to transform the academic landscape. A major component of this transformation is the integration of entrepreneurship within our universities and in the curriculum nationally.

“I congratulate the winners who are part of a movement to turn the tide for economic growth in our country. May they continue with their businesses and mentor those who are still finding their way.”

Said Dr Kirston Greenop, Head of Corporate Citizenship, Standard Bank South Africa: “For us at Standard Bank, there are only two ways to achieve growth in this country –  through education and with entrepreneurship. With these awards, and with the work done by EDHE, you combine the two and so, for us, it is an absolute win/win.

“Without a small and medium enterprise and entrepreneur base, this country is lost. We need to get the EDHE message out there to a wider community while celebrating its work. It is an absolute truth that when we invest in entrepreneurs, we invest in hope, in self-determination and in community upliftment.”

Mr Mahlubi “Chief” Mabizela, Director: Operations and Sector Support at USAf, emphasised the importance of entrepreneurship for higher education.

“Every graduate of higher education must come out equipped with entrepreneurial skills, whether or not they intend to use them thereafter. Universities cannot simply produce graduates who wait for jobs that may never come. Universities that embrace entrepreneurship remain relevant by aligning curriculum with societal and economic needs while producing well rounded graduates. Entrepreneurship fosters creativity, problem solving and adaptability; skills which are critical to compete, to participate in society, and for social development. In other words, entrepreneurship is not just about profit but about social innovation.

“Our ultimate aim is to have entrepreneurship embedded in the DNA of higher education, not as an elective, but as a pillar of the sector’s transformation,” he concluded.

Participating in the panel of judges for the 2025 EDHE Entrepreneurship Intervarsity Awards were Mrs Pabalelo Banks, representing Analytics X, Mr Billy Bokako from the Small Enterprises Development Agency, Ms Khwezi Cenenda, representing Avocado Vision,  Ms Onthatile Ditshego from the SAB Foundation, Ms Uve Nathi Gcilishe from The Innovation Hub) and Mr Marshall Grant, representing the Garden Route Innovation Hub.

Pioneering Retinal Implant Restores Reading Vision to Blind Eyes

Study participant Sheila Irvine training with the device. Credit: Moorfields Eye Hospital

After being treated with an electronic eye implant paired with augmented-reality glasses, people with sight loss have recovered reading vision, reports a trial involving a UCL and Moorfields clinical researcher.

The results of the European clinical trial, published in The New England Journal of Medicine, showed 84% of participants were able to read letters, numbers and words using prosthetic vision through an eye that had previously lost its sight due to the untreatable progressive eye condition, geographic atrophy with dry age-related macular degeneration (AMD).

Those treated with the device could also read, on average, five lines of a vision chart; some participants could not even see the chart before their surgery.

The trial, with 38 patients in 17 hospital sites across five countries, was testing a pioneering device called PRIMA, with Moorfields Eye Hospital being the sole UK site. All patients had lost complete sight in their eye before receiving the implant.

Dry AMD is a slow deterioration of the cells of the macula over many years, as the light-sensitive retinal cells die off. For most people with dry AMD, they can experience a slight loss of central vision. Through a process known as geographic atrophy (GA), it can progress to full sight loss in the eye, as the cells die and the central macula melts away. There is currently no treatment for GA, which affects 5 million people globally. All participants in this trial had lost the central sight of the eye being tested, leaving only limited peripheral vision.

This revolutionary new implant is the first ever device to enable people to read letters, numbers and words through an eye that had lost its sight.

Mr Mahi Muqit, associate professor in the UCL Institute of Ophthalmology and senior vitreoretinal consultant at Moorfields Eye Hospital, who led the UK arm of the trial, said: “In the history of artificial vision, this represents a new era. Blind patients are actually able to have meaningful central vision restoration, which has never been done before.

“Getting back the ability to read is a major improvement in their quality of life, lifts their mood and helps to restore their confidence and independence. The PRIMA chip operation can safely be performed by any trained vitreoretinal surgeon in under two hours – that is key for allowing all blind patients to have access to this new medical therapy for GA in dry AMD.”

The procedure involves a vitrectomy, where the eye’s vitreous jelly is removed from between the lens and the retina, and the surgeon inserts the ultra-thin microchip, which is shaped like a SIM card and just 2mm x 2mm. This is inserted under the centre of a patient’s retina, by creating a trapdoor into which the chip is posted. The patient uses augmented-reality glasses, containing a video camera that is connected to a small computer, with a zoom feature, attached to their waistband.

Around a month or so after the operation, once the eye has settled, the new chip is activated. The video camera in the glasses projects the visual scene as an infra-red beam directly across the chip to activate the device. Artificial intelligence (AI) algorithms through the pocket computer process this information, which is then converted into an electrical signal. This signal passes through the retinal and optical nerve cells into the brain, where it is interpreted as vision. The patient uses their glasses to focus and scan across the main object in the projected image from the video camera, using the zoom feature to enlarge the text. Each patient goes through an intensive rehabilitation programme over several months to learn to interpret these signals and start reading again.

No significant decline in existing peripheral vison was observed in trial participants.

These findings pave the way for seeking approval to market this new device.

Sheila Irvine, one of Moorfields’ patients on the trial who was diagnosed with age-related macular degeneration, said: “I wanted to take part in research to help future generations, and my optician suggested I get in touch with Moorfields. Before receiving the implant, it was like having two black discs in my eyes, with the outside distorted.

“I was an avid bookworm, and I wanted that back. I was nervous, excited, all those things. There was no pain during the operation, but you’re still aware of what’s happening. It’s a new way of looking through your eyes, and it was dead exciting when I began seeing a letter. It’s not simple, learning to read again, but the more hours I put in, the more I pick up.

“The team at Moorfields has given me challenges, like ‘Look at your prescription’, which is always tiny. I like stretching myself, trying to look at the little writing on tins, doing crosswords.

“It’s made a big difference. Reading takes you into another world, I’m definitely more optimistic now.”

The global trial was led by Dr Frank Holz of the University of Bonn, with participants from the UK, France, Italy and the Netherlands.

The PRIMA System device used in this operation is being developed by Science Corporation (science.xyz), which develops brain-computer interfaces and neural engineering.

Mr Muqit added: “My feeling is that the door is open for medical devices in this area, because there is no treatment currently licensed for dry AMD – it doesn’t exist.

“I think it’s something that, in future, could be used to treat multiple eye conditions.”

More about the device:

The device is a novel wireless subretinal photovoltaic implant paired with specialised glasses that project near-infrared light to the implant, which acts like a miniature solar panel.

It is 30 micrometres/microns (0.03mm) thick, about half the thickness of a human hair.

A zoom feature gives patients the ability to magnify letters. It is implanted in the subretinal layer, under the retinal cells that have died. Until the glasses and waistband computer are turned on, the implant has no visual stimulus or signal to pass through to the brain.

In addition to practising their reading and attending regular training, patients on the trial were encouraged to explore ways of using the device. Sheila chose to learn to do puzzles and crosswords while one of the French patients used them to help navigate the Paris Metro – both tasks being more complex than reading alone.

Source: University College London

Implant Treats Type 1 Diabetes by Oxygenating Insulin-producing Cells

A 3D map of the islet density routes throughout the healthy human pancreas. Source: Wikimedia CC0

Cornell researchers have developed an implant system that can treat Type 1 diabetes by supplying extra oxygen to densely packed insulin-secreting cells, without the need for immunosuppression. The system could also potentially provide long-term treatment for a range of chronic diseases.

The findings appear in Nature Communications. The co-first authors were former postdoctoral researcher Tung Pham and doctoral candidate Lora (Phuong) Tran.

The technology builds off previous implantable encapsulation devices developed in the lab of Minglin Ma, professor of biological and environmental engineering in the College of Agriculture and Life Sciences (CALS) and the paper’s senior author.

Ma has explored a variety of ways to address Type 1 diabetes, which is typically managed through daily insulin injections or insulin pumps, but even with that treatment, patients still suffer the devastating effects of the disease.

Ma’s previous implantable devices have proved effective in controlling blood sugar in diabetic mice, but they can only last so long.

“One of the major challenges is the implant itself often dies due to the lack of oxygen after implantation,” Tran said. “In our lab, they had success in mice that lived over one year, and they controlled the diabetes very effectively with some small capsules without oxygen generation. However, when we scale up, we need more cells, we need more density, especially. We need a higher dose. If we implant without generating oxygen, the cells often die within two weeks.”

Ma’s team developed the new system in collaboration with electrochemical researchers from Giner Inc, including co-author Linda Tempelman, PhD ’93.

The key components of the system are a cylindrical capsule with a ring-shaped cross-section that contains transplanted insulin-secreting cells, and an electrochemical oxygen generator that is roughly the size of a dime and removeable. A nanofibrous membrane outside the capsule protects the cells from the host body’s immune system; a permeable membrane in the core of the capsule allows the central supply of oxygen to reach the ring of cells.

“We have to meet two requirements,” Tran said. “The first is immune protection. And second, you have to maintain mass transfer, like the glucose and other nutrients and molecules that can go in and out.”

Working with Dr James Flanders, associate professor emeritus in the College of Veterinary Medicine, the researchers successfully tested the system in rat models.

“It’s the proof of concept. We really proved that oxygenation is important, and oxygenation will support high cell-density capsules,” Tempelman said. “The capsules are immune protective and last for a long time without having some kind of fouling of the membrane. The body never likes when you put a foreign substance in. So that’s the engineering in the Ma Lab, to look for materials and coatings for the materials that are immune protective, but also don’t invoke excess response from the body because of the material.”

The new system would enable a much greater number of the 2 million people who suffer from Type 1 diabetes in the US to now have an islet transplant or cell therapy without requiring immune suppression, which is considered too dangerous for routine use. Also, the new system can provide much tighter sugar control, effectively curing the disease and enabling the person to eat, drink and exercise like everyone else. 

The next step will be to implant the system in a pig model, and also test it with human stem cells. The researchers are interested in eventually trying to use the system for implanting different cell types in humans for long-term treatment of chronic diseases, according to Tempelman, who is CEO of Persista Bio Inc., a new startup she founded with Ma and Flanders that is licensing these technologies.

“We see an age where people will be getting implants with allogeneic cells from other human beings, from stem cell lines, and using it long term to treat things that your body is missing,” Tempelman said. “Here we’re missing insulin. In pain control, maybe you need more endorphins or some other molecule. In enzyme replacement therapy, you need more enzymes. We’re interested in things like other autoimmune diseases where there’s inflammation that’s out of control.

“So maybe you could put a small molecule in that would treat inflammation, and then someone, like a Lupus patient, wouldn’t have to take an oral medication. They could just have a low-level implant that provides a low amount of it.”

Source: Cornell University

Oxford Researchers Develop Uniquely Shaped Microstent to Combat Glaucoma

A schematic of the eye’s anterior segment, demonstrating the anatomical placement of the microstent. The stent diverts aqueous humour from the anterior chamber to the suprachoroidal space through the flexible tube, creating a subconjunctival bleb supported by the expanding element. Credit: Yunlan Zhang, Zhong You, Jared Ching.

A team of researchers at the University of Oxford have unveiled a pioneering ‘microstent’ which could revolutionise treatment for glaucoma, a common but debilitating condition. The study has been published in The Innovation, Cell Press.

Glaucoma is a leading cause of vision loss, second only to cataracts. Globally, 7.7 million people were blind or visually impaired due to glaucoma in 2020. The condition can cause irreversible damage to the optic nerve, due to increased pressure within the eyeball. Current treatment options – principally surgery to create openings in the eye or insert tubes to drain fluid – are highly invasive, carry risk of complications, and have limited durability.

‘Our deployable microstent represents a significant advancement in glaucoma treatment,’ said lead author Dr Yunlan Zhang (University of Oxford at the time of the study/University of Texas). ‘Current surgical implants for this type of glaucoma have been shown to have limited long-term effectiveness, being susceptible to failure due to fibrosis (scarring) in the eye.’ 

The new microstent features a unique structural shape that allows it to expand once in the eye. At 200µm, less than a quarter of a millimetre, the stent’s tiny diameter enables it to fit within the needle of a standard hypodermic syringe, for minimally-invasive insertion. Once in place and expanded, the microstent spans the fluid-filled space between the white of the eye and the membrane that covers it.

By supporting this space, the stent reduces the excessive fluid buildup and resulting intraocular pressure in the eye which is responsible for the most common type of glaucoma, primary open-angle glaucoma. Initial trials carried out in rabbits found that the microstents lowered eye pressure in less than a month with minimal inflammation and scarring. Furthermore, the microstent achieved a greater reduction of eye pressure than a standard tubular implant.

This development has the potential to transform the landscape of glaucoma therapy. By offering an enhanced solution in the minimally invasive glaucoma surgery field that combines mechanical innovation with biocompatibility, we hope to improve patient outcomes and quality of life.

Senior co-author Dr Jared Ching (Department of Engineering Science, University of Oxford).

Senior co-author, Professor Zhong You (Department of Engineering Science, University of Oxford) said: ‘Our microstent is made from a durable and super-flexible nickel-titanium alloy called nitinol, renowned for its proven long-term safety for ocular use. Its unique material and structural properties help prevent subsequent movement, improve durability, and ensure long-term efficacy.’

The research team used advanced modelling techniques to guide the microstent’s design and ensure compatibility with the anatomy of the eye. The device’s superelastic properties enable it to accommodate how the eye changes and stretches over time without permanent deformation, enhancing its durability and functionality.

Over half a million people in the UK have glaucoma – 2% of everyone over the age of 40 – and it is one of the most common causes of blindness worldwide. The introduction of this microstent could mark a pivotal step in enhancing treatment efficacy and accessibility.

The study ‘A Novel Deployable Microstent for the Treatment of Glaucoma has been published in The Innovation, Cell Press.

Source: Oxford University

Building Better Cerebrospinal Fluid Shunts for the Brain

Schematic of approach to simulating brain shunt fluid dynamics. Credit: Harvard SEAS

Millions of people worldwide suffer from hydrocephalus, a condition which recently received greater attention when Billy Joel announced his diagnosis. Treatment usually involves surgical placement of shunts to divert cerebrospinal fluid away, but this procedure often leads to complications, infections, and multiple re-treatments.  

Bioengineers in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have now developed a new computational model to aid the creation of shunts tailored to individual patients’ anatomy and needs. The model combines brain anatomy, fluid flow, and biomolecular transport dynamics to simulate shunt performance with pinpoint accuracy.

The work was supported by federal funding from the National Science Foundation and published in Proceedings of the National Academy of Sciences. It was led by SEAS postdoctoral fellow Haritosh Patel, who works in the labs of Joanna Aizenberg, Professor of Materials Science at SEAS and Professor of Chemistry and Chemical Biology; and Venkatesh Murthy, Professor of Molecular and Cellular Biology and Director of the Center for Brain Science.

Repeat surgeries due to infection or obstruction

Tens of thousands of shunt procedures are performed annually in the U.S. — many of which are repeat surgeries due to the inserted devices becoming blocked or obstructed, or the patient suffering an infection.

“Some elderly patients told me they had had over 10 surgeries — one every two to three years,” Patel said. “We really wanted to understand why this was happening, and we realised that many of these obstructions and infections were tied to shunt designs that didn’t fully consider fluid dynamics as a fundamental part of their geometry. We noticed that the tubing geometry used in shunts closely resembles the kind of piping we rely on in household plumbing. While that simplicity has its advantages, we saw an opportunity to explore more creative, biomimetic solutions that better suit the complexity of the brain’s environment.”

Pursuing the problem from both a material and design perspective, the team quickly realized there was no universally accepted fluid flow model for the brain ventricle space to guide them. “Okay, well, we can’t test our devices in a model, so why don’t we first make a better model?” Patel said.

Computational tool simulates fluid flow in brain

The result is their computational tool, called BrainFlow, which combines detailed anatomical and physiological features of the brain to simulate the flow of cerebrospinal fluid flow in the presence of shunt implants.

 The model incorporates patient-specific medical imaging data along with pulse-induced flow to mimic a patient’s cerebrospinal fluid dynamics, all to offer insight into optimal shunt design, placement, and even choice of materials.

“We believe that our model, combined with novel geometries and materials improvements such as anti-biofouling coatings developed in my lab, could lead to smoother integration of optimized, patient-specific medical devices into patients’ brains, with less likelihood of complications, and a better quality of life,” Aizenberg said.

The Harvard team is currently conducting studies that use the model to test different designs of shunts and calculate their efficacy.

Source: Harvard John A. Paulson School of Engineering and Applied Sciences

Implantable Device Could Save Diabetes Patients from Dangerous Hypoglycaemia Episodes

The new implant carries a reservoir of glucagon that can be stored under the skin and deployed during an emergency — with no injections needed.

Caption:A new implantable device carries a reservoir of glucagon that can be stored under the skin and could save diabetes patients from dangerously low blood sugar. Image: Courtesy of the researchers

Anne Trafton | MIT News

For people with Type 1 diabetes, developing hypoglycaemia, or low blood sugar, is an ever-present threat. When glucose levels become extremely low, it creates a life-threatening situation for which the standard treatment of care is injecting a hormone called glucagon.

As an emergency backup, for cases where patients may not realise that their blood sugar is dropping to dangerous levels, MIT engineers have designed an implantable reservoir that can remain under the skin and be triggered to release glucagon when blood sugar levels get too low.

This approach could also help in cases where hypoglycaemia occurs during sleep, or for diabetic children who are unable to administer injections on their own.

“This is a small, emergency-event device that can be placed under the skin, where it is ready to act if the patient’s blood sugar drops too low,” says Daniel Anderson, a professor in MIT’s Department of Chemical Engineering, a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science (IMES), and the senior author of the study. “Our goal was to build a device that is always ready to protect patients from low blood sugar. We think this can also help relieve the fear of hypoglycaemia that many patients, and their parents, suffer from.”

The researchers showed that this device could also be used to deliver emergency doses of epinephrine, a drug that is used to treat heart attacks and can also prevent severe allergic reactions, including anaphylactic shock.

Siddharth Krishnan, a former MIT research scientist who is now an assistant professor of electrical engineering at Stanford University, is the lead author of the study, which appears today in Nature Biomedical Engineering.

Emergency response

Most patients with type 1 diabetes use daily insulin injections to help their body absorb sugar and prevent their blood sugar levels from getting too high. However, if their blood sugar levels get too low, they develop hypoglycaemia, which can lead to confusion and seizures, and may be fatal if it goes untreated.

To combat hypoglycaemia, some patients carry preloaded syringes of glucagon, a hormone that stimulates the liver to release glucose into the bloodstream. However, it isn’t always easy for people, especially children, to know when they are becoming hypoglycaemic.

“Some patients can sense when they’re getting low blood sugar, and go eat something or give themselves glucagon,” Anderson says. “But some are unaware that they’re hypoglycaemic, and they can just slip into confusion and coma. This is also a problem when patients sleep, as they are reliant on glucose sensor alarms to wake them when sugar drops dangerously low.”

To make it easier to counteract hypoglycaemia, the MIT team set out to design an emergency device that could be triggered either by the person using it, or automatically by a sensor.

The device, which is about the size of a quarter, contains a small drug reservoir made of a 3D-printed polymer. The reservoir is sealed with a special material known as a shape-memory alloy, which can be programmed to change its shape when heated. In this case, the researcher used a nickel-titanium alloy that is programmed to curl from a flat slab into a U-shape when heated to 40 degrees Celsius.

Like many other protein or peptide drugs, glucagon tends to break down quickly, so the liquid form can’t be stored long-term in the body. Instead, the MIT team created a powdered version of the drug, which remains stable for much longer and stays in the reservoir until released.

Each device can carry either one or four doses of glucagon, and it also includes an antenna tuned to respond to a specific frequency in the radiofrequency range. That allows it to be remotely triggered to turn on a small electrical current, which is used to heat the shape-memory alloy. When the temperature reaches the 40-degree threshold, the slab bends into a U shape, releasing the contents of the reservoir.

Because the device can receive wireless signals, it could also be designed so that drug release is triggered by a glucose monitor when the wearer’s blood sugar drops below a certain level.

“One of the key features of this type of digital drug delivery system is that you can have it talk to sensors,” Krishnan says. “In this case, the continuous glucose-monitoring technology that a lot of patients use is something that would be easy for these types of devices to interface with.”

Reversing hypoglycaemia

After implanting the device in diabetic mice, the researchers used it to trigger glucagon release as the animals’ blood sugar levels were dropping. Within less than 10 minutes of activating the drug release, blood sugar levels began to level off, allowing them to remain within the normal range and avert hypoglycaemia.

The researchers also tested the device with a powdered version of epinephrine. They found that within 10 minutes of drug release, epinephrine levels in the bloodstream became elevated and heart rate increased.

In this study, the researchers kept the devices implanted for up to four weeks, but they now plan to see if they can extend that time up to at least a year.

“The idea is you would have enough doses that can provide this therapeutic rescue event over a significant period of time. We don’t know exactly what that is — maybe a year, maybe a few years, and we’re currently working on establishing what the optimal lifetime is. But then after that, it would need to be replaced,” Krishnan says.

Typically, when a medical device is implanted in the body, scar tissue develops around the device, which can interfere with its function. However, in this study, the researchers showed that even after fibrotic tissue formed around the implant, they were able to successfully trigger the drug release.

The researchers are now planning for additional animal studies and hope to begin testing the device in clinical trials within the next three years.

“It’s really exciting to see our team accomplish this, which I hope will someday help diabetic patients and could more broadly provide a new paradigm for delivering any emergency medicine,” says Robert Langer, the David H. Koch Institute Professor at MIT and an author of the paper.

Other authors of the paper include Laura O’Keeffe, Arnab Rudra, Derin Gumustop, Nima Khatib, Claudia Liu, Jiawei Yang, Athena Wang, Matthew Bochenek, Yen-Chun Lu, Suman Bose, and Kaelan Reed.

The research was funded by the Leona M. and Harry B. Helmsley Charitable Trust, the National Institutes of Health, a JDRF postdoctoral fellowship, and the National Institute of Biomedical Imaging and Bioengineering.

Reprinted with permission of MIT News

Hearing Devices Increase Social Connectedness and Reduce Mortality

Photo by Brett Sayles

Hearing loss doesn’t just affect how people hear the world — it can also change how they connect with it. New research from the University of Southern California, published in JAMA Otolaryngology – Head & Neck Surgery, is the first to link hearing aids and cochlear implants, surgically implanted devices that help those with profound hearing loss perceive sound, to improved social lives among adults with hearing loss. 

“We found that adults with hearing loss who used hearing aids or cochlear implants were more socially engaged and felt less isolated compared to those who didn’t use them,” said lead researcher Janet Choi, MD, MPH, an otolaryngologist with Keck Medicine at USC. “This suggests that hearing devices may help prevent the social disconnection and broader health consequences that can follow untreated hearing loss.” 

Hearing loss affects an estimated 40 million American adults, yet many go untreated. When left unaddressed, hearing loss can make communication difficult, leading people to withdraw from conversations and social activities, according to Choi.  

Previous research has shown that over time, social withdrawal can reduce mental stimulation and increase the risk of loneliness, anxiety, depression, cognitive decline and dementia. It has also linked chronic social isolation to biological and neurological changes, including increased brain inflammation and alterations in brain structure.  

“Understanding the link between hearing loss, hearing device use and social isolation is crucial,” said Choi. “Until this study, it has been unclear whether hearing devices could help reverse the isolation.”   

Choi and her fellow researchers conducted a comprehensive, systematic review and meta-analysis of 65 previously published studies, encompassing over five thousand participants, on how hearing aids and cochlear implants affect three key measures: social quality of life, perceived social handicap, which refers to the limitations and frustrations hearing loss can create in social situations, and loneliness.  

The researchers found that adults using hearing devices feel more socially connected and less limited in social situations. They are better able to engage in group conversations and feel more at ease in noisy or challenging listening environments. Participants also reported feeling less socially handicapped by their hearing loss, with fewer barriers and frustrations during interactions and an improved ability to stay engaged without feeling excluded. This increased confidence can help users connect more easily with family, friends and colleagues, leading to stronger feelings of belonging and reduced social anxiety. The study also suggested hearing devices may reduce loneliness, although further research is needed in this area, according to Choi. 

Those with cochlear implants reported the most improvement in their social quality of life. This is likely because cochlear implants offer greater hearing restoration than hearing aids, especially for individuals with more severe hearing loss. As a result, they may experience more noticeable improvements in social engagement once their hearing is restored. 

While it was outside the scope of the study to measure how better social lives relate to improved cognitive outcomes, Choi believes there may be a connection, as previous research has found managing hearing loss may be key to reducing the risk of cognitive decline and dementia. “While our study didn’t directly measure cognitive outcomes, the improvements we saw in communication and social engagement suggest that by restoring clearer communication, hearing devices may help preserve cognitive health by keeping the brain more actively involved and people more connected,” Choi said. 

This research follows a January 2024 study by Choi showing that adults with hearing loss who use hearing aids have an almost 25% lower risk of mortality, suggesting that treating hearing loss can improve lifespan as well as social quality of life.  

“These new findings add to a growing body of research showing that hearing health is deeply connected to overall well-being,” said Choi. “We hope this encourages more people to seek treatment and helps clinicians start conversations with patients about how hearing devices can improve their quality of life.”

Source: University of Southern California – Health Sciences