UBC Reports | Vol.
50 | No. 2 | Feb.
New Invention Saves Pain for Patients and Doctors
Making needles easier to give and easier to take
By Michelle Cook
(with files from ErinRose Handy, Applied Science)
Joanne Driscoll (not her real name) has a deteriorating disc
in her spine. To slow the deterioration down, doctors must
insert a long needle filled with a steroid into her back every
It's an experience marked with fear and anxiety and sometimes,
when the needle misses its mark, excruciating pain.
"I have heard others scream when this happens and I've wanted
to scream myself. One time it felt like molten lava coursing
down my leg," Driscoll says. "It is also very stressful for
the person inserting the needle. Once after many painful failed
attempts, a resident actually asked my supervising doctor
to put on his gloves and take over my treatment."
Needle insertion is one of the most common medical procedures.
It can also be one of the most nerve-racking for both medical
practitioners and patients -- especially when it involves
the 15-cm-long needles used to reach regions deep inside the
Now, a group of UBC engineers has developed a steerable needle
to help doctors hit their target on the first try -- and save
their patients the stress and pain of multiple insertions.
"What's interesting about this needle is that instead of
putting a straight needle into the body and hoping it goes
towards its target, we have a needle that can steer itself
from the tip. It can guide itself. It's a very smart needle,"
says Prof. Robert Rohling, a professor jointly appointed to
the departments of mechanical engineering and electrical and
computer engineering and one of the needle's inventors.
The steerable needle prototype looks like a stainless-steel
barbeque lighter with a 15-cm hypodermic needle attached to
it. What makes it unique is that within its barrel, there
is a second, flexible needle with a curved tip. The second
needle can be steered by a joystick on the needle's handle,
giving doctors greater accuracy in locating their target,
and make corrections along the way.
Rohling says the steerable needle won't change the basic
aspects of the biopsy procedure. Like a conventional needle,
it is inserted into the body by puncturing the skin at the
best access point, and pushed in until the tip reaches the
desired target. The big difference is that, once inserted,
the doctor can use the thumb-controlled joystick to steer
it along straight or curved paths.
He envisions doctors using the device in conjunction with
ultrasound -- another medical technique he is working to improve.
"The steerable needle will give doctors an extra degree
of control," Rohling says. "We expect the first applications
will be the more difficult, deeper insertions [but] it is
also possible that the steerable needle will help a novice
reach their target on the first attempt -- without trial and
As the director of Surgical Techniques Training Programs
for UBC's medical undergraduates, Karim Qayumi has guided
many residents through the needle insertion procedure. He's
also performed countless needle insertions himself. He says
it's not an easy experience.
He says the main challenge for doctors is having to imagine
where to direct the needle, without actually being able to
see where it's going. It's a skill that comes only with experience.
The potential dangers are numerous: a misplaced needle can
cause bleeding, pain, or seed healthy cells with cancerous
"There's a certain anxiety when you insert a big needle into
someone and you don't know whether you're going to get results
or not," Qayumi says. "If the biopsy is in a remote place,
even experienced doctors can have difficulties. They've got
to get to the target area without damaging tissue or causing
Although he has not used the steerable needle, Qayumi welcomes
Rohling's research, with fellow inventors Tim Salcudean, an
engineering professor, and master's engineering students Richelle
Ebrahimi and Stephen Okazawa, to improve the technique of
Okazawa says the biggest hurdle in designing the steerable
needle prototype was getting the mechanical and electrical
parts to work together with the computer software designed
to run the needle. But the result is a one-of-a-kind device
that the research team hopes will take some of the discomfort
out of a painful procedure, and cut down on the time needed
to perform it.
Rohling adds that while the cost of the system is still more
than a regular, disposable needle, the health-care savings
will be in the reduction of time it takes doctors to perform
The researchers' next step is to prepare the prototype for
The steerable needle hasn't been used on humans -- yet. Instead,
researchers have been trying it out on tissue phantoms --
simulated pieces of tissue that Okazawa cooked up in his own
kitchen using agar, a gelatinous substance obtained from seaweed,
and then embedded with peas and grapes for target practice.
Even before doctors get their hands on the first prototype,
its inventors are already thinking about how to improve the
steerable needle's capabilities.
"We look at these types of applications and think ahead to
even more advanced systems where we have computer-aided control,"
Rohling says. "The first iteration has a little joystick and
the control is all in the operator's [doctor's] hand. The
second may be to let the computer handle the joystick and
monitor the needle's progress and provide the corrections.
Eventually, a robotics system may take care of both pushing
the needle and steering the tip."