Posted by 
Needles are among the most common instrumental tools for eye treatment, few changes have been made to them in that time and the shots in locations like the back of the eye must be given by specially trained professionals to reduce the risks of mistakes and complications.
With a simple change to hypodermic needles, researchers at Brigham and Women’s Hospital have created a variation on the tool that automatically stops when it reaches the type of tissue it needs to deliver medication to. Saline, penicillin, insulin, contrast dyes, fluid extractions – needles make it possible to deliver countless drugs into the human body and to remove fluids and blood from the body.
Injections are so commonplace that we hardly think about who and how someone is sticking our arms or buttocks.
But if you find yourself staring a long, skinny needle point in the eye, trusting that it will slip into the small but safe space the clinician is aiming for, you might wish they were guided by a little more than their own sense of pressure and touch.
You wouldn’t be without cause either. Injuries from infections are very rare, but they happen. A study of one million arm injections over 10 years found that nearly 300 led to nerve injuries. Even a shot in the arm, administered incorrectly, can be debilitating. Rare though it is, a ‘shoulder injury related to vaccine administration’ (SIRVA) can cause extreme pain and even lasting muscle damage – so even a flu shot comes with at least one worrisome risk.
Eye injections have similarly low rates of complications to other shots, but there is the chance that a botched shot could leave a patient with a serious infection and even make them go blind. And needles are crucial to a number of more invasive, delicate procedures too.
For example, over 70 percent of pregnant women get epidural shots or other spinal anesthesia when they go into labor.
For example, over 70 percent of pregnant women get epidural shots or other spinal anesthesia when they go into labor.
The shot does wonders for cutting through the pain, but getting is a painful shot in the dark itself. A clinician has to push a needle through a woman’s back, including a thick layer of ligament, into the epidural space, very near the spine. But if the needle goes too far, it can puncture the spine’s casing, allowing cerebrospinal fluid to leak out and causing migraine-like headaches. Treating the headaches requires drawing blood from elsewhere – like an arm – then injecting it back near the spine, to act as a ‘patch,’ explains Dr Jeff Karp, study author and a biomedical engineer at Brigham and Women’s Hospital.
Dialysis patients, too, are at risk of disastrous needle mistakes. In order to receive dialysis, which requires a lot of blood flow, a fistula, a wider vessel joining a vein and and an artery has to be created for the dialysis catheter to be inserted into. This process takes months, but can be ruined immediately if a needle passes all the way through a blood vessel.
Researchers at Brigham and Women’s Hospital, in Massachusetts, had some ideas about how to prevent these painful mistakes.
Researchers at Brigham and Women’s Hospital, in Massachusetts, had some ideas about how to prevent these painful mistakes.
To develop their enhanced needles, the team focused on the suprachoridal space – the ‘micro-thin’ area beneath the outermost layer of the eyeball, which they describe as being ‘among the most unforgiving sites’ for injections. Doctors want to be able to inject drugs as close to the part of the eye where fluid builds up and can cause vision damage as possible, but getting it right takes the most delicate touch to judge when the needle has reached the space but not delved past it into the the choroid or retina.
Not only can a miss cause potential damage it may mean the drug doesn’t reach its target as efficiently. So the Brigham and Women’s team made a needle that automatically pushes through thick tissues that are not where an injection should be delivered, and stops as soon as it reaches the liquid-filled ones clinicians aim for. ‘We’ve endowed the plunger with an added functionality such that if the needle is in a thick tissue, the plunger actually pushes the needle forward,’ explains Dr Karp.
There are no bells, whistles or electronics involved. The team’s invention works with the a syringe’s plunger system to make the needle keep going until it reaches the right space, and stop and release whatever solution it contains once it does. 10sharesAn end to vaccine injuries? New ‘smart’ needle guides itself to the right spot and won’t inject if it senses the wrong tissue.
Complications from injections are rare, but a poor injection can mean a longer wait for medicine to work or getting a second one This is particularly true for shots to the tiny space under the surface of the eye Scientists at Brigham and Women’s Hospital in Boston have developed a needle that ‘feels’ pressure changes and automatically stops if you’re going too far A new pressure sensitive needle knows when it comes into contact with different tissue types, making injections into sensitive areas like the eye easier.
But if the needle goes too far, it can puncture the spine’s casing, allowing cerebrospinal fluid to leak out and causing migraine-like headaches.
Treating the headaches requires drawing blood from elsewhere – like an arm – then injecting it back near the spine, to act as a ‘patch,’ explains Dr Jeff Karp, study author and a biomedical engineer at Brigham and Women’s Hospital. This happens in somewhere between one and 10 percent of pregnant women, which adds up quickly.
Complications from injections are rare, but a poor injection can mean a longer wait for medicine to work or getting a second one This is particularly true for shots to the tiny space under the surface of the eye Scientists at Brigham and Women’s Hospital in Boston have developed a needle that ‘feels’ pressure changes and automatically stops if you’re going too far A new pressure sensitive needle knows when it comes into contact with different tissue types, making injections into sensitive areas like the eye easier.
But if the needle goes too far, it can puncture the spine’s casing, allowing cerebrospinal fluid to leak out and causing migraine-like headaches.
Treating the headaches requires drawing blood from elsewhere – like an arm – then injecting it back near the spine, to act as a ‘patch,’ explains Dr Jeff Karp, study author and a biomedical engineer at Brigham and Women’s Hospital. This happens in somewhere between one and 10 percent of pregnant women, which adds up quickly.
Dialysis patients, too, are at risk of disastrous needle mistakes.
In order to receive dialysis, which requires a lot of blood flow, a fistula, a wider vessel joining a vein and and an artery has to be created for the dialysis catheter to be inserted into. This process takes months, but can be ruined immediately if a needle passes all the way through a blood vessel. Researchers at Brigham and Women’s Hospital, in Massachusetts, had some ideas about how to prevent these painful mistakes.
To develop their enhanced needles, the team focused on the suprachoridal space – the ‘micro-thin’ area beneath the outermost layer of the eyeball, which they describe as being ‘among the most unforgiving sites’ for injections.
In order to receive dialysis, which requires a lot of blood flow, a fistula, a wider vessel joining a vein and and an artery has to be created for the dialysis catheter to be inserted into. This process takes months, but can be ruined immediately if a needle passes all the way through a blood vessel. Researchers at Brigham and Women’s Hospital, in Massachusetts, had some ideas about how to prevent these painful mistakes.
To develop their enhanced needles, the team focused on the suprachoridal space – the ‘micro-thin’ area beneath the outermost layer of the eyeball, which they describe as being ‘among the most unforgiving sites’ for injections.
Doctors want to be able to inject drugs as close to the part of the eye where fluid builds up and can cause vision damage as possible, but getting it right takes the most delicate touch to judge when the needle has reached the space but not delved past it into the the choroid or retina. Not only can a miss cause potential damage it may mean the drug doesn’t reach its target as efficiently.
So the Brigham and Women’s team made a needle that automatically pushes through thick tissues that are not where an injection should be delivered, and stops as soon as it reaches the liquid-filled ones clinicians aim for.
So the Brigham and Women’s team made a needle that automatically pushes through thick tissues that are not where an injection should be delivered, and stops as soon as it reaches the liquid-filled ones clinicians aim for.
‘We’ve endowed the plunger with an added functionality such that if the needle is in a thick tissue, the plunger actually pushes the needle forward,’ explains Dr Karp. There are no bells, whistles or electronics involved. The team’s invention works with the a syringe’s plunger system to make the needle keep going until it reaches the right space, and stop and release whatever solution it contains once it does.
During tests on sheep’s eyes, the device is automatically stopped from going in any deeper once it senses a layer of different pressure, namely, fluid beneath the sclera. Importantly, the new form of needle can be purchased about as cheaply as the older, dumber ones.
And there’s no reason to believe the system’s usefulness would only be isolated to the eye.
During tests on sheep’s eyes, the device is automatically stopped from going in any deeper once it senses a layer of different pressure, namely, fluid beneath the sclera. Importantly, the new form of needle can be purchased about as cheaply as the older, dumber ones.
And there’s no reason to believe the system’s usefulness would only be isolated to the eye.