MEDICINE A cerebral blood clot can cause
severe brain injury and potentially death if it is
not treated quickly. Studies show that when
the blood clot is removed within 90 minutes,
the patient’s chances of survival increase
dramatically. But it is a difficult process that
requires a surgeon either to insert a catheter
through the blood vessels to deliver dissolving
medication to the right place, or to remove
the blood clot by forcing or sucking it out.
Surgeons will soon have a new tool.
Engineers in robotics from the Massachusetts
Institute of Technology in the US have
developed a robotic worm to reach hard-to-
access blood vessels in the brain. The snake-
like robot is introduced through the blood
vessels like a catheter, controlled from the
outside by means of magnets, so it avoidshitting vessel walls where it could cause a
cerebral haemorrhage. The robotic worm has
a diameter of only 0.6mm, with a nickel and
titanium core that ensures it swings back to
its original position when it is not affected by
magnets. Around the core is a layer of rubber
mixed with magnetic particles. On the
outside, the worm is lined with hydrogel that
makes it pass easily through the blood vessels.
So far, the scientists have tested the
robotic worm in a model brain, where the
blood vessels are made of glass. The next step
is to test it in real brains from deceased
people. According to the scientists, magnetic
control could allow even remote treatment of
patients, so surgery for some could happen
much more quickly, reducing the risk of
permanent brain injury from the clot.YOO
NHO (^) K
IM
ET (^) A
L./
MIT
Robot worm removes
blood clots in the brain
A new robot can make its way to areas of the brain that
doctors cannot reach. Their goal is to remove lethal blood clots.
Magnetism controls
snakes in the brain
The remote magnetic effect
allows doctors to guide an
artificial worm through the
narrow blood vessels of the
brain, ensuring that it doesn’t
hit the vessel walls, causing
cerebral haemorrhage.
THE WORM IS FULL
OF MICROMAGNETS
1 The robotic arm is full of magnetic particles
that function as small bar
magnets that are all facing
in the same direction.MAGNETIC FIELD
SETS THE COURSE
2 The worm bends towards the north
pole of the magnetic field.
If the field disappears, the
snake unbends again.Mmicro-agnets External layer of hydrogelCore made of
nickel and titaniumROBOTIC WORMBLOOD VESSELS
IN BRAIN MODELM
AG
N
ET
IC(^) F
IE
LD
N
S
Rubber compound
with mparticlesagnetic
An island of floating lava might have
carried new life from the Pacific to
the Great Barrier Reef in Australia.
But then again, it might not have.
JOSHUA STEVENS/USGS/NASA
ECOLOGY Coral reefs
throughout the world are under
threat, and with them the most
species-rich ecosystems of the
oceans. Coral reefs suffer from
even small rises in ocean
temperatures because the heat
reduces the quantity of algae on
which the corals feed. Moreover,
the corals are affected by increased
ocean acidity, the result of CO 2
emissions, making it harder for
the small creatures to build their
calcium skeletons.
Some 89% of the world’s
biggest coral reef, the Great Barrier
Reef off Queensland’s north-east
corner, is thought to be affected.
But unexpected assistance
appeared last year in a floating
island of hardened lava in the
Pacific, heading towards the reef,
and due to arrive during the
production of this issue of
Australian Science Illustrated.
According to some scientists,
the lava could bring new life in the
shape of algae, snails, worms, and
not least corals which could
contribute to rebuilding the reef.
The lava island was created in
eruptions from an undersea
volcano near Tonga, and covers
more than 150km^2 , consisting
of pumice of varying sizes, each
lump being a floating ecosystem
bringing new life from the Pacific.
Other scientists disagree,
saying that corals dislike a moving
home, and would in any case have
no mechanism to jump from the
lava island to the reef below.
Will the lava
island benefit
the reef?
2km
scienceillustrated.com.au | 15