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The Neurography Institute was founded
in May of 2000 to serve as the exclusive licensee and provider
of the patented MR neurography medical scanning technology. Based
in Santa Monica, California, the Neurography Institute serves
thousands of patients worldwide each year, conducting specialized
scans and providing their physicians with expert readings of
the results that help determine the best course of action for
the patient's condition.
Invented by Dr. Aaron Filler and
protected by United
States patents numbered 5,560,360
(awarded October 1, 1996) and 5,706,813 (awarded
January 13, 1998), MR neurography is a specialized form of medical
scanning using magnetic resonance imaging to see otherwise "invisible"
soft tissues of the nervous system. In detail:
MR Neurography is a means of optimizing an
MRI scan for sensitivity to special biophysical properties of
nerve. In MRI scanning, the scanner is able to detect subtle
differences in the behavior of protons which are most abundant
in water. Water in different tissues may have different appearances
in the image because of effects of material dissolved in the
water; these materials affect the tumbling rate of the water
molecules. In addition, tissue may also be affected by magnetic
properties of materials dissolved in or near the water. Finally
the way in which water molecules move or diffuse in tissues can
affect their appearance. There are also protons in different
forms and the second most abundant are those participating in
fat or lipid molecules. In MRI scanning, it is possible to use
radiofrequency pulses and magnetic field shifts to accentuate
the appearance of one type of proton over the appearance of another.
In addition to the fine aspects of the collection of the image,
there are a variety of specialized computer processing steps required
to complete the process of presenting a detailed image of the nerve
for review. The final image is then interpreted by a specially
trained and credentialled neuroradiologist. These doctors have
special experience in reviewing and anlyzing nerve images.
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Started: a Step-by-Step Guide to MR Neurography
The development of MR neurography: a detailed
history
Some nerves are small, but some are actually fairly
large — the sciatic
nerve can be as big around as one's thumb. However, no matter the
size, until
the arrival of MR neurography, there was no reliable way to see
nerves.
"Arrival" is really the correct term, because the technology
shot from nowhere to a thousand
miles an hour almost overnight; the very first human images revealed
spectacular details
about the internal structure and injury pattern that had never
before been seen. News media ran with the story; the discovery
was published in Lancet, the international medical journal
of record, along with the New York Times and ABC News'
Peter Jennings.
Though some nerves are quite small,
the problem with getting visible images of them had nothing to
do with their size. Rather, it had to do with the inability of
any existing imaging method to tune in to
the particular physiology of a nerve, in order to make it stand
out (or highlight) in an image.
Nerves can take curving, complex courses through
the human body. Because of this,
it's important to "remove" everything else from an image
to provide the doctor with a clear depiction of a patient's condition.
MRI scanners produce a series of images of the human body that
resemble
"slices" — helpful for viewing many internal organs
and structures. However, nerves typically travel through the slices,
as opposed to within them. It's the medical imaging equivalent
of finding a needle in a haystack.
MR neurography depicts the nerve as the brightest
structure in an image. This makes it easy for doctors to "remove"
everything else from the image and follow complex, three-dimensional
nerve-tree structures through a series of MRI image "slices." This
information, in turn, allows physicans to correctly diagnose and
treat nerve-based conditions.
How does MR neurography make a nerve bright? Unlike
other internal highlighting methods that rely on contrast agents
(e.g. dyes), MR neurography is based on a method developed by Dr.
Filler that tunes the MRI scanning station to the unique aspects
of the water signal of a nerve. Part of his innovation involved
the discovery that unique features of nerve tissue could be detected
with specially designed MRI magnetic "pulse sequences" — thereby
sending pulses especially for nerves and getting the results no
other MRI scan had ever achieved.
What is a "pulse sequence"? It is the basic method
of operation of an MRI scanning machine, involving a rapid, complex
orchestra of radiofrequency and magnetic pulses that are sent out,
pass through the patient's body, and are returned to the machine
for interpretation as viewable images. If you've ever had an MRI
scan and heard the loud "knocking" sounds, that's a fast-running
pulse sequence. Changes in the rhythm of the knocking indicates
differing pulse sequences.
But there's more to an MR neurography image scan
than just tuning an MRI device to send out specialized pulse sequences.
There are issues involved in the way image "slices" are oriented
for specific nerve types, and there is three-dimensional image
processing that is unique to the MR neurography method. Using complex
imaging software specially designed for this process, the neuroradiologist
can review and compare the raw imagery and the processed, final
images, producing a stunningly detailed perspective of a patient's
branching nerve tree — and any problems that may be affecting that
structure.
And in this manner, then, the neurosurgeons of Neurography
Institute are able to accurately diagnose your condition, and recommend
a success-based method of resolution to help you alleviate your
condition and return to a pain-free lifestyle.
How did all this get started? MR neurography was
a classic "Eureka" moment, and it's just one of the many
inventions and discoveries made by Dr.
Aaron Filler, co-founder and chief of clinical services of
Neurography Institute.
Dr. Filler first became interested in seeing images
of nerves while working
on his Harvard University PhD thesis in the mid-1980s. While attempting
to map complex branching nerve trees that control the back muscles
in the human body, he found that no matter where he turned in medicine
or science, there was simply no way to "see" nerves in medical
images of the human body.
After beginning
his neurosurgery residency
training in Seattle, Washington, Dr. Filler began work on the nerve
imaging
dilemma. His original plan was to develop a specialized contrast
agent for
nerves. The idea was to use a biological phenomenon called "axonal
transport" to carry contrast molecules to the interior of
nerves. He started
the initial axonal transport project in Seattle in 1988. Two years
later, Dr. Filler began a one-year clinical rotation in London,
England, as part of his residency. It was during this period that
great gains were made, as he began his MRI phase of contrast research
which was funded by the Neurosciences Research Foundation
of Atkinson Morley's Hospital (AMH) in Wimbledon, famed for its
tennis event. It was at AMH in the 1970s that Godfrey N. Hounsfield
designed and built the first CT scanner, a feat for which he won
a Nobel Prize in Medicine in 1979.
Most of Dr. Filler's research was performed at the
associated "parent" hospital up the road, St. George's Hospital
Medicine Center in Tooting. There, he had access to some of the
world's most advanced medical-research MRI systems in existence.
Amazingly, though most of this work was performed in 1990, the
magnet systems at St. George's remain well ahead of most comparable
systems even today.
Keep in mind that Dr. Filler's mission at this point
was to devise a contrast agent to allow the viewing of nerves in
MR images — and that modern MR neurography does not require any
contrast agents whatsoever. So what happened?
Dr. Filler did succeed
in creating injectable contrast agents to enhance MRI scans, and
the research progressed so well that he stayed an additional two-and-a-half
years to further his studies.
But in discussing his research with
an Oxford University-trained physicist by the name of Franklyn
Howe, Dr. Filler realized he needed to try a slightly different
direction. As Dr. Howe argued, using contrast agents to identify
nerves in MRI scans was providing a
"circular" reasoning to his research: Dr. Filler was
using the contrast agent both to show nerves and show the agent.
Thus, his experiments wouldn't be fully valid until he was able
to depict nerves in MRI scans without the agent, in order to prove
the success of the agent in brightening nerve structures.
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First MR neurography imaging
case: sciatic nerve injury
Dr. Aaron Filler's pulse sequence
innovation that created modern MR neurography
had its first major test in November 1992.
Using a clinical General Electric Signa MRI
scanner modified to use his now-patented pulse
sequence, Dr. Filler and his research partners
were able to produce the above scan that highlights
the sciatic nerve structure while darkenening
all other surrounding tissue. This was
the first image that demonstrated the ability
to capture the fascile pattern inside the nerve;
it was also the first image to prove that the
structure highlighted was indeed a nerve.
The imagery received extensive
worldwide attention in the medical and news
media, and was published in Lancet in 1993.
A Cross
section of the thigh. The arrow indicates the
sciatic nerve. This patient had suffered a stab
wound to the the thigh which had severed his
sciatic nerve.
B Blown-up
view of the sciatic nerve revealing the internal
fascicle structure.
C A
three dimensional reconstruction of the nerve
based on "maximum intensity projection" of
the nerve. This image closely matches the shape
of the sciatic nerve seen in the image (D).
D Intraoperative
photograph taken during surgery. The photo shows
the cut sciatic nerve. The arrow indicates the
suture line where nerve grafts have been sown
into place. |
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Determined to accomplish this, Dr. Filler set out
in late 1991 and early 1992 to devise a new MR pulse sequence strategy
that would make it possible to reliably identify a nerve in an
image, thereby allowing him to prove that his contrast-agent experiments
were performing as his research had indicated.
After much reflection on the biophysics of nerves
and the complex
physics of MR pulse sequences, Dr. Filler assembled a radically
unique pulse
sequence strategy. It was based on simultaneously suppressing the
image signal from
all the other tissues, with the pulse sequence actually "squeezing"
together a variety of differing imaging strategies.
Before it was
tested, Dr.
Howe predicted failure because he felt all this simultaneous suppression
would leave no signal at all to measure. However, the first image
run in February of
1992 produced a startling result — a
strange new image type, completely blacked out except for the intense
bright
signal of the nerve. Everything else had disappeared completely,
leaving the nerves to glow brightly, like the smile on the Cheshire
cat in
Alice in Wonderland.
Additional testing over the next few
days confirmed the results: Dr. Filler's new pulse sequence had
isolated nerves in a magnetic resonance scan for the first time.
Professor Griffiths, the lab director and editor-in-chief
of one of the leading academic MRI journals, agreed that this was
an astonishing advance in MRI technology — a pure nerve image with
no contrast agent required.
Dr. Filler's pulse sequence required an extraordinarily
advanced MRI scanner.
However, the nerve imaging technique acted as a Rosetta Stone;
now that nerves could be instantly and reliably identified, Drs.
Filler and Howe were able to rapidly test a variety of other MRI
sequences, each producing a similar effect. Within a
week, they discovered a second sequence that had the potential
to work on standard 1.5 Tesla clinical MRI scanners.
Soon thereafter, Dr. Filler returned to his neurosurgical
residency program in
Seattle where he asked Dr. Jay Tsuruda to test the new sequence
on one of
the 1.5 Tesla General Electric magnetic resonance scanners at the
University of Washington Hospital. The
first patient was imaged in November of 1992 and the spectacular
first image
was produced (SEE INSET) — the picture seen around the world
in the Lancet, New York
Times, and on ABC News and CNN when it was published in March
1993.
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Started: a Step-by-Step Guide to MR Neurography
There is only one source for MR neurography:
the Nerve Scan Centers of the Neurography Institute
Only the Nerve Scan Centers of the Neurography Institute
are licensed to perform MR neurography medical scans. If you are
offered an "MR neurography" by anyone else, it is, simply
put, not the real thing.
The reason is simple: an MR neurography is more than
just a medical scan. It is the collaboration between the Nerve
Scan Center, the patient, the patient's referring physician, and
the neuroradiologists and neurosurgeons of the Neurography Institute.
Once the scan is taken, it is encrypted for HIPAA-compliant
security and transmitted to the Neurography Institute for complex
processing. The final step is a series of readings by authoritative
neuroradiologists overseen by Dr. Aaron Filler, providing the referring
physician and the patient with the highest level of expertise and
recommendations possible.
The result is an accurate scan, accurate diagnosis
and comprehensive strategy for treatment. Exclusively from Neurography
Institute.
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Medical Papers and Reviews
on MR Neurography
MR neurography is a prominent discussion point in
medical journals and related media. Please click on any of the
following links to learn more about the MR neurography innovation
in medicine today through papers and reviews he has principally
authored, beginning with this first public report issued in a 1993
edition of Lancet.
Report
of the first clinical Neurography image: Lancet, 1993
First
report of the general capabilities of Neurography: Journal
of Neurosurgery, 1996
Major
recent review of the state of the art in Neurography: Neurologic
Clinics, 2005
Large
scale formal outcome trial of Neurography and Sciatica: Journal
of Neurosurgery, 2005
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Started: a Step-by-Step Guide to MR Neurography
Neurography Institute Payments
Payment for MR neurography services is expected
at the time of service. Neurography Institute's billing office
is pleased to provide medical claims filing assistance for those
seeking reimbursement. Partial payments are accepted and patients
are urged to discuss their specific financial concerns with a billing
representative. Please
click here to download and complete our
Financial Agreement form, which should be brought to your appointment.
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Started: a Step-by-Step Guide to MR Neurography
Become a Neurography Institute
Nerve Scan Center
Our network is growing, thanks to the results provided by MR
neurography for patients and their physicians. Consider
adding MR neurography to your imaging center. For franchising
information, please email us at franchise@neurography.com.
Corporate contact information
Neurography Institute
2716 Ocean Park Blvd., Suite 3035
Santa Monica, CA 90405
877-PAIN-MRI
877-724-6674
or
310-664-3944
email: contact@neurography.com |