Showing posts with label Hydrocephalus. Show all posts
Showing posts with label Hydrocephalus. Show all posts
Thursday, January 2, 2014
Hydrocephalus: sensors monitor cerebral pressure
If the pressure in a patient's brain is too high, physicians implant a system in the head that regulates the pressure. A sensor can now measure and individually adjust brain pressure. The sensor system is approved for use as a long-term implant.
Urinary incontinence, a shuffling gait, and deteriorating reasoning skills are all indicators pointing to a Parkinsonian or Alzheimer type disease. An equally plausible explanation is hydrocephalus, commonly known as "water on the brain." With this diagnosis, the brain produces either too much cerebral fluid, or it cannot "drain off" these fluids with adequate sufficiency. The consequence: Pressure in the brain rises sharply, resulting in damage. A shunt system – a kind of silicon tube that physicians implant into the patient's brain, provides relief. It draws off superfluous fluid from there, for example, into the abdominal cavity. The heart of this shunt system is a valve: If the pressure increases above a threshold value, then the valve opens; if it declines again, then the valve closes.
In rare cases, over-drainage may occur. The cerebral pressure lowers too much, the cerebral ventricles are virtually squeezed out. Until now, physicians could only detect and verify such over-drainage through elaborate and costly computer and magnetic resonance tomography.
Cerebral pressure measurable anytime
With a new kind of sensor, things are different: If it is implanted into the patient's brain with the shunt system, the physicians could read out brain pressure using a hand-held meter: within seconds, anytime and without complex investigation. Researchers at the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg, working jointly with Christoph Miethke GmbH and Aesculap AG, engineered these sensors.
If the patient complains of discomfort, then the physician merely needs to place the hand- held meter outside, on the patient's head. The device sends magnetic radio waves and supplies the sensor in the shunt with power- the implant is "awakened," measures tem- perature and pressure in the cerebral fluid, and transmits these data back to the handheld device. If the pressure on the outside of the desired area, the physician can set the valve on the shunt system from the outside as needed, and individually adjusted to the patient. "The sensor is an active implant, which also takes over measurement functions, in contrast to a stent or a tooth implant," says Michael Görtz, head of pressure sensor technology at IMS.
The implant must be biocompatible; the body cannot reject it. Researchers had to ensure that the body also would not attack the implant. "The defense response behaves just like an aggressive medium, that would even dilute the silicon of the electronics over the course of time," explains Görtz. Miethke therefore completely encases the implant into a thin metal casing. "We can still supply it with power from the outside through the metal casing, measure cerebral pressure through the housing and transmit the recorded data outside, through the metal to the reader," Görtz explains. To do so, the correct metal had to be found. The coating may not be thicker than the walls of a soft drink can – in other words, much thinner than one millimeter. The researchers even developed the handheld reading device, together with the electronics, through which it communicates with the sensor.
The sensor is ready for serial production, and was already approved by Miethke. The company has already initiated the market launch of the system. "The sensor sets the basis for the further development through to theranostic implants – a neologism derived from the words "therapy" and "diagnostic." In a few years, the sensor could then not only record cerebral pressure and develop a diagnosis on the basis of this, but also properly adjust the pressure independently, immediately on its own and thus, take over the therapy process," says Görtz.
Wednesday, November 2, 2011
Wis. doctor creates possible life-saving device
October 29, 2011
MADISON, Wis. (AP) — Ten years ago, working on a night shift as a resident in a Madison emergency room, Josh Medow found himself treating a child with hydrocephalus, a disease in which fluid accumulates in the brain. The child had a headache and the anxious parents feared the worst — that a shunt designed to drain the fluid had failed and potentially lethal pressure was building up in the boy's brain.
Medow realized there was no way to check whether pressure was indeed increasing, short of intrusive and painful procedures. The child ended up in the operating room.
Today, Medow, 38, and an attending neurosurgeon at UW Hospital, is on the verge of patenting a device he invented that allows doctors and even parents to easily keep track of cranial pressure in a child with hydrocephalus.
The long journey from that night in the emergency room to the invention of the tiny silicon implant that now sits on his desk is partly a tale of how medical devices come to be. But it is also a story of invention, full of twists and turns, moments of insight (that light bulb going on over the head), night-long sessions in Medow's basement where he initially cobbled together a prototype, and a trip or two to Radio Shack.
Medow has long had an interest in how things work. Before getting his medical degree at UW-Madison, he earned a degree in applied life studies and biomechanics at the University of Illinois. When he was a boy, he liked to build radios. When he was 10, he bought himself a Commodore 64, a very early computer, and taught himself computer programming.
"I used to tinker," Medow said. "I worked at a Radio Shack when I was in high school."
Though he is now a doctor, Medow still views the world through the eyes of that tinkering boy. He sees problems that could be solved by devices and he thinks about how to build them.
About 700,000 people have hydrocephalus, a disease in which the body is missing the ability to re-absorb the cerebral spinal fluid that bathes the brain. That fluid is normally made and drained three times a day, Medow said.
But in those with the disease, it builds up and creates dangerous pressure that can lead to brain damage, stroke and blindness. Normally, a shunt keeps the fluid drained, but studies show half of all shunts fail within two years. Sometimes, for example, they get clogged; fluid builds up and pressure increases.
Medow couldn't stop thinking about the problem. There had to be a better way, he thought, to know whether a shunt has failed than doing surgery on the shunt itself, an operation that can cost as much as $15,000 and cause considerable pain.
That night, when he got home, he made the initial drawings for a device that could eventually be made small enough to be implanted to monitor pressure and allow parents and doctors to know whether a shunt had failed without doing invasive surgery.
The initial idea was fairly simple and drew on a basic principle of magnetism and electricity arrived at by English scientist Michael Faraday in 1831: electromagnetic induction. Faraday found that when he manipulated the magnetic field around an electromagnet by closing and opening an electrical circuit he had built around the magnet, an electrical current could be detected in a separate conductor nearby.
Perhaps, Medow thought, he could build a device using electromagnets that would collect electrical signals from the brain and send them to a separate device that would translate the information into something useful — such as a pressure reading. He could use a device called a transducer to translate pressure into electrical current. The higher the frequency, the higher the pressure in the brain.
Medow went to Radio Shack and bought $75 worth of electronics gear. Working at a coffee table in his basement he cobbled together a prototype on a piece of plywood.
It worked.
But, for a long time the prototype remained a prototype, a bunch of electrical equipment mounted on a piece of plywood that Medow had painted red. He was deep into his residency, working 100 hours a week at the hospital. Sometimes, he'd take friends down to his basement and show them what he'd made.
"They'd say, 'That's really nerdy, now let's go out for a beer,'" Medow recalled.
Eventually, however, Medow found numerous supporters on the UW-Madison campus who helped him move the work forward. They included John Webster, a professor emeritus of biomedical engineering, who became a champion of Medow's after he realized the value of the invention. Other supporters included Dr. Robert Dempsey, chair of neurosurgery at UW Hospital, and Dr. Berman Iskandar, professor of neurosurgery.
Last April, Medow was awarded a $300,000 grant from the Hartwell Foundation that would help the Department of Biomedical Engineering downsize the prototype into a tiny implant made from pliable silicon and shaped to fit neatly beneath a rounded skull.
Signals from the implant — called a transcutaneous inductive pressure monitor — will be read on a handheld device about the size of a television remote.
The final product of Medow's imagination now sits on his desk. He hopes to see it tested in human trials over the next three years.
"It's neat being a doctor and knowing there is a problem to solve," Medow said. "And it's neat knowing how to build a device that seems to have the potential to work. I just knew there had to be a better way."
MADISON, Wis. (AP) — Ten years ago, working on a night shift as a resident in a Madison emergency room, Josh Medow found himself treating a child with hydrocephalus, a disease in which fluid accumulates in the brain. The child had a headache and the anxious parents feared the worst — that a shunt designed to drain the fluid had failed and potentially lethal pressure was building up in the boy's brain.
Medow realized there was no way to check whether pressure was indeed increasing, short of intrusive and painful procedures. The child ended up in the operating room.
Today, Medow, 38, and an attending neurosurgeon at UW Hospital, is on the verge of patenting a device he invented that allows doctors and even parents to easily keep track of cranial pressure in a child with hydrocephalus.
The long journey from that night in the emergency room to the invention of the tiny silicon implant that now sits on his desk is partly a tale of how medical devices come to be. But it is also a story of invention, full of twists and turns, moments of insight (that light bulb going on over the head), night-long sessions in Medow's basement where he initially cobbled together a prototype, and a trip or two to Radio Shack.
Medow has long had an interest in how things work. Before getting his medical degree at UW-Madison, he earned a degree in applied life studies and biomechanics at the University of Illinois. When he was a boy, he liked to build radios. When he was 10, he bought himself a Commodore 64, a very early computer, and taught himself computer programming.
"I used to tinker," Medow said. "I worked at a Radio Shack when I was in high school."
Though he is now a doctor, Medow still views the world through the eyes of that tinkering boy. He sees problems that could be solved by devices and he thinks about how to build them.
About 700,000 people have hydrocephalus, a disease in which the body is missing the ability to re-absorb the cerebral spinal fluid that bathes the brain. That fluid is normally made and drained three times a day, Medow said.
But in those with the disease, it builds up and creates dangerous pressure that can lead to brain damage, stroke and blindness. Normally, a shunt keeps the fluid drained, but studies show half of all shunts fail within two years. Sometimes, for example, they get clogged; fluid builds up and pressure increases.
Medow couldn't stop thinking about the problem. There had to be a better way, he thought, to know whether a shunt has failed than doing surgery on the shunt itself, an operation that can cost as much as $15,000 and cause considerable pain.
That night, when he got home, he made the initial drawings for a device that could eventually be made small enough to be implanted to monitor pressure and allow parents and doctors to know whether a shunt had failed without doing invasive surgery.
The initial idea was fairly simple and drew on a basic principle of magnetism and electricity arrived at by English scientist Michael Faraday in 1831: electromagnetic induction. Faraday found that when he manipulated the magnetic field around an electromagnet by closing and opening an electrical circuit he had built around the magnet, an electrical current could be detected in a separate conductor nearby.
Perhaps, Medow thought, he could build a device using electromagnets that would collect electrical signals from the brain and send them to a separate device that would translate the information into something useful — such as a pressure reading. He could use a device called a transducer to translate pressure into electrical current. The higher the frequency, the higher the pressure in the brain.
Medow went to Radio Shack and bought $75 worth of electronics gear. Working at a coffee table in his basement he cobbled together a prototype on a piece of plywood.
It worked.
But, for a long time the prototype remained a prototype, a bunch of electrical equipment mounted on a piece of plywood that Medow had painted red. He was deep into his residency, working 100 hours a week at the hospital. Sometimes, he'd take friends down to his basement and show them what he'd made.
"They'd say, 'That's really nerdy, now let's go out for a beer,'" Medow recalled.
Eventually, however, Medow found numerous supporters on the UW-Madison campus who helped him move the work forward. They included John Webster, a professor emeritus of biomedical engineering, who became a champion of Medow's after he realized the value of the invention. Other supporters included Dr. Robert Dempsey, chair of neurosurgery at UW Hospital, and Dr. Berman Iskandar, professor of neurosurgery.
Last April, Medow was awarded a $300,000 grant from the Hartwell Foundation that would help the Department of Biomedical Engineering downsize the prototype into a tiny implant made from pliable silicon and shaped to fit neatly beneath a rounded skull.
Signals from the implant — called a transcutaneous inductive pressure monitor — will be read on a handheld device about the size of a television remote.
The final product of Medow's imagination now sits on his desk. He hopes to see it tested in human trials over the next three years.
"It's neat being a doctor and knowing there is a problem to solve," Medow said. "And it's neat knowing how to build a device that seems to have the potential to work. I just knew there had to be a better way."
Monday, May 4, 2009
Medical Technology: 'SmartShunt' To Regulate Pressure In The Brain
Medical Technology: 'SmartShunt' To Regulate Pressure In The Brain
ScienceDaily (Apr. 19, 2009) — ETH Zurich researchers have simulated the motion of the cerebrospinal fluid in the human brain. They are using the results to develop a self-regulating system to treat hydrocephalus.
Cerebrospinal fluid is a colorless liquid surrounding the brain and the spinal cord and filling the cavities in the brain. It protects the brain from impact and vibrations, carries nutrients to it and harmful substances away from it, and acts as one of the brain’s communication routes. If too much of this fluid is produced or too little flows away, excessive pressure builds up in the head and hydrocephalus occurs.
The liquid flows into the abdomen
As a rule nowadays, hydrocephalus is treated by using a “shunt”: this involves implanting into the patient a thin tube that carries excess cerebrospinal fluid from the head into the abdomen via a pressure relief valve. However, this process often drains away too much or too little fluid. Most valves can no longer be adjusted after implantation. Although some valves have this option, the patient must visit the doctor for adjustments to be made.
ETH Zurich researchers led by Dimos Poulikakos, Professor of Thermodynamics, and Vartan Kurtcuoglu, Director of the Biofluidics group in the Laboratory for Thermodynamics in Emerging Technologies, want to go one step further. They are working on a “SmartShunt”, a self-regulating pressure relief device. To achieve their aim they must understand exactly how the cerebrospinal fluid flows within the skull. For this, they simulated the motion of the fluid in three dimensions on a computer. Initial results were published in the February issue of the Journal of Biomechanical Engineering. Its title page shows a graphic image of the results, the research group having already made the title page in the January issue with a publication on aortic aneurysms (see the Literature references).
A brain scan is the first step
The cerebrospinal fluid fills the space between the skull and the brain, called the sub-arachnoid space, in which it pulses in a cycle controlled indirectly by the heart. With each heartbeat, the heart pumps blood through the brain, causing the blood vessels to expand and the space available for the cerebrospinal fluid to decrease correspondingly. The blood flows away again before the next heartbeat, and the space for the cerebrospinal fluid increases.
The publication came into being in collaboration with Peter Bösiger, Professor at the Institute of Biomedical Technology of ETH Zurich. His group scanned the sub-arachnoid space of a healthy 25-year-old man by magnetic resonance imaging (MRI). They also used a special MRI technique to measure the velocity of the fluid in three planes to provide the boundary conditions for the calculations.
The scientists built a computer model based on the results of the measurements. They used a series of partial differential equations to describe the motion of the cerebrospinal fluid. At the same time, they had to take into account the fact that the sub-arachnoid space is criss-crossed by a sort of fine, networklike bar of tissues that retard the movement of the fluid. Instead of computing with the single bar, they represented the sub-arachnoid space in their model as a uniform porous medium similar to a sponge.
Valve for self-regulation
Based on the results, the researchers in the multi-disciplinary “SmartShunt” Project are now developing the basis for a shunt to control the outflow of cerebrospinal fluid automatically in accordance with the patient’s specific needs. The goal is a valve that controls the pressure in the patient’s head in real time, saving him or her regular visits to the doctor.
Dimos Poulikakos says, “We attach importance to the fact that definitereal medical problems are addressed in the continuation of basic research.” The researchers work in close collaboration with the medical staff of the University Hospital Zurich and with other ETH Zurich institutes. The Swiss National Science Foundation is funding the interdisciplinary project to the tune of approximately CHF 850,000. Poulikakos plans to start developing the actual product together with the industry in about three year’s time.
Knowledge of the cerebrospinal fluid motion will also be useful for other medical applications. The liquid plays a part in Alzheimer’s disease, in multiple sclerosis and in meningitis. In addition, drugs that cannot cross the blood-brain barrier can be injected into the cerebrospinal fluid, from where they reach the brain. In other cases, for example regarding painkillers, injection into the cerebrospinal fluid can allow the dose to be decreased to reduce side-effects.
ScienceDaily (Apr. 19, 2009) — ETH Zurich researchers have simulated the motion of the cerebrospinal fluid in the human brain. They are using the results to develop a self-regulating system to treat hydrocephalus.
Cerebrospinal fluid is a colorless liquid surrounding the brain and the spinal cord and filling the cavities in the brain. It protects the brain from impact and vibrations, carries nutrients to it and harmful substances away from it, and acts as one of the brain’s communication routes. If too much of this fluid is produced or too little flows away, excessive pressure builds up in the head and hydrocephalus occurs.
The liquid flows into the abdomen
As a rule nowadays, hydrocephalus is treated by using a “shunt”: this involves implanting into the patient a thin tube that carries excess cerebrospinal fluid from the head into the abdomen via a pressure relief valve. However, this process often drains away too much or too little fluid. Most valves can no longer be adjusted after implantation. Although some valves have this option, the patient must visit the doctor for adjustments to be made.
ETH Zurich researchers led by Dimos Poulikakos, Professor of Thermodynamics, and Vartan Kurtcuoglu, Director of the Biofluidics group in the Laboratory for Thermodynamics in Emerging Technologies, want to go one step further. They are working on a “SmartShunt”, a self-regulating pressure relief device. To achieve their aim they must understand exactly how the cerebrospinal fluid flows within the skull. For this, they simulated the motion of the fluid in three dimensions on a computer. Initial results were published in the February issue of the Journal of Biomechanical Engineering. Its title page shows a graphic image of the results, the research group having already made the title page in the January issue with a publication on aortic aneurysms (see the Literature references).
A brain scan is the first step
The cerebrospinal fluid fills the space between the skull and the brain, called the sub-arachnoid space, in which it pulses in a cycle controlled indirectly by the heart. With each heartbeat, the heart pumps blood through the brain, causing the blood vessels to expand and the space available for the cerebrospinal fluid to decrease correspondingly. The blood flows away again before the next heartbeat, and the space for the cerebrospinal fluid increases.
The publication came into being in collaboration with Peter Bösiger, Professor at the Institute of Biomedical Technology of ETH Zurich. His group scanned the sub-arachnoid space of a healthy 25-year-old man by magnetic resonance imaging (MRI). They also used a special MRI technique to measure the velocity of the fluid in three planes to provide the boundary conditions for the calculations.
The scientists built a computer model based on the results of the measurements. They used a series of partial differential equations to describe the motion of the cerebrospinal fluid. At the same time, they had to take into account the fact that the sub-arachnoid space is criss-crossed by a sort of fine, networklike bar of tissues that retard the movement of the fluid. Instead of computing with the single bar, they represented the sub-arachnoid space in their model as a uniform porous medium similar to a sponge.
Valve for self-regulation
Based on the results, the researchers in the multi-disciplinary “SmartShunt” Project are now developing the basis for a shunt to control the outflow of cerebrospinal fluid automatically in accordance with the patient’s specific needs. The goal is a valve that controls the pressure in the patient’s head in real time, saving him or her regular visits to the doctor.
Dimos Poulikakos says, “We attach importance to the fact that definitereal medical problems are addressed in the continuation of basic research.” The researchers work in close collaboration with the medical staff of the University Hospital Zurich and with other ETH Zurich institutes. The Swiss National Science Foundation is funding the interdisciplinary project to the tune of approximately CHF 850,000. Poulikakos plans to start developing the actual product together with the industry in about three year’s time.
Knowledge of the cerebrospinal fluid motion will also be useful for other medical applications. The liquid plays a part in Alzheimer’s disease, in multiple sclerosis and in meningitis. In addition, drugs that cannot cross the blood-brain barrier can be injected into the cerebrospinal fluid, from where they reach the brain. In other cases, for example regarding painkillers, injection into the cerebrospinal fluid can allow the dose to be decreased to reduce side-effects.
Wednesday, March 18, 2009
Birth brain defect could be treated with vitamin supplement
Birth brain defect could be treated with vitamin supplement
March 17th, 2009
(PhysOrg.com) -- Pioneering research published today suggests that a vitamin supplement taken during pregnancy could prevent hydrocephalus - one of the common forms of birth brain defect.
Scientists at The University of Manchester and Lancaster University say laboratory tests have shown that administering a combination of vitamins (tetrahydrofolate and folinic acid), dramatically reduces the risk of hydrocephalus.
Dr Jaleel Miyan, who led the research in Manchester’s Faculty of Life Sciences, said: “Hydrocephalus is a condition arising from an abnormal build-up of fluid within the chambers of the brain.
“This fluid build-up - usually caused by a blockage in the fluid’s pathway due to trauma, infection or abnormal development - is associated with an increase in the pressure on the brain resulting in brain damage. When this happens, doctors can relieve this pressure only by performing surgery.
“Our studies have revealed that hydrocephalus is associated with a change in the composition of the cerebrospinal fluid and it is this chemical change that prevents normal growth of the brain cells resulting in arrested brain development. This occurs prior to any brain damage due to raised pressure.”
The findings of the study, funded by Association for Spina Bifida & Hydrocephalus (ASBAH) and published in the Journal of Neuropathology and Experimental Neurology, led the team to examine ways of stimulating cell division to encourage normal brain development.
Dr Miyan explained: “A combination of tetrahydrofolate and folinic acid - both naturally occurring substances - stimulated brain cell growth and had a significant positive effect on brain development in laboratory experiments on rats and reduced the incidence of hydrocephalus.
“In laboratory experiments, the combined folate supplement works at any stage during pregnancy which means that it may be effective even if it is commenced after the diagnosis of hydrocephalus is made at an 18 to 20 week pregnancy scan.
March 17th, 2009
(PhysOrg.com) -- Pioneering research published today suggests that a vitamin supplement taken during pregnancy could prevent hydrocephalus - one of the common forms of birth brain defect.
Scientists at The University of Manchester and Lancaster University say laboratory tests have shown that administering a combination of vitamins (tetrahydrofolate and folinic acid), dramatically reduces the risk of hydrocephalus.
Dr Jaleel Miyan, who led the research in Manchester’s Faculty of Life Sciences, said: “Hydrocephalus is a condition arising from an abnormal build-up of fluid within the chambers of the brain.
“This fluid build-up - usually caused by a blockage in the fluid’s pathway due to trauma, infection or abnormal development - is associated with an increase in the pressure on the brain resulting in brain damage. When this happens, doctors can relieve this pressure only by performing surgery.
“Our studies have revealed that hydrocephalus is associated with a change in the composition of the cerebrospinal fluid and it is this chemical change that prevents normal growth of the brain cells resulting in arrested brain development. This occurs prior to any brain damage due to raised pressure.”
The findings of the study, funded by Association for Spina Bifida & Hydrocephalus (ASBAH) and published in the Journal of Neuropathology and Experimental Neurology, led the team to examine ways of stimulating cell division to encourage normal brain development.
Dr Miyan explained: “A combination of tetrahydrofolate and folinic acid - both naturally occurring substances - stimulated brain cell growth and had a significant positive effect on brain development in laboratory experiments on rats and reduced the incidence of hydrocephalus.
“In laboratory experiments, the combined folate supplement works at any stage during pregnancy which means that it may be effective even if it is commenced after the diagnosis of hydrocephalus is made at an 18 to 20 week pregnancy scan.
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