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References: Europe
Crisp images of the upper neck
with Planmeca’s CBCT device
A few years ago, Seppo Villanen,
a Finnish physiatrist specialised
in pain management, visited
Planmeca’s stand at the Finnish
Medical Convention and saw a
CBCT image of a patient with an
obvious sequela of a fracture in the
neck area. This gave him the idea
of using a dental 3D X-ray imaging
device for imaging patients with
neck problems. The idea turned
out to be a success, and nearly 30
patients have now been imaged
in cooperation with Pantomo Oy,
a company offering dental X-ray
imaging services.
COPY HANNA KORLIN IMAGES JUHA KIENANEN
Seppo Villanen has his practice
at medical center Mehiläinen,
which is located in the Helsinki methods complement each other. In
Metropolitan Area. The patients
he has referred for a CBCT (cone beam
computed tomography) examination
have mostly been patients suffering
from pain in the upper neck. “During a
routine MRI scan of the neck, the upper
neck is usually left outside the image,
since the scan acquires transverse
slices from the C3 vertebra downwards.
What’s more, a regular X-ray examina-
tion of the neck is routinely performed
in a manner that also leaves the upper
neck outside the image. CBCT imaging,
on the other hand, covers the entire
upper neck, from the base of the skull to
the C4 vertebra, which is precisely the
area that is often missing from routine
studies.”
Villanen’s neck patients are sent to
Oral and Maxillofacial Radiology Center
Pantomo Oy for imaging with Planmeca
ProMax® 3D, and the images are inter-
preted by radiologist Raija Mikkonen.
“We have cooperated with Raija for
years”, says Villanen.
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Seppo Villanen, Specialist in physical medicine and pain treatment (on the right)
and Radiologist Raija Mikkonen.
In most cases, CBCT imaging is done Moreover, the method produces very
to support MRI imaging, since the thin slices, with feasible thicknesses of
0.1 to 0.2mm. In hospitals, CT scans for
some cases, however, a CBCT scan is all traumas are usually performed with a
that is needed:“It does not provide an slice thickness of 2mm, and MRI scans
insight to soft tissues, but if the image are sometimes performed with a slice
is sufficient to provide an answer to the thickness of up to 5mm.
current question, other methods are not
needed.” “The thinner the slice, the more reliable
it is when you are studying small things”,
“One of the many benefits says Villanen. “Thin slices have a better
of CBCT imaging is the low resolution and afford better measurments.
radiation dose compared to A 2mm slice does reveal large fractures,
e.g. a traditional CT scan.” but small avulsion fractures might remain
undetected.”
Conversely, bony structures do not
show up well in MRI images, and small Furthermore, a CBCT scan can be
bones can be easily confused with scar post-processed to include all required slice
tissue. In a CBCT image, even small thicknesses. “They can also be acquired in
changes in the bone are plainly visible”, a high resolution CT scan, but that would
describes Mikkonen. produce an even higher radiation dose”,
describes Mikkonen.
Thin slices, low radiation doses and
a natural head position Also the patient position is better in
One of the many benefits of CBCT a CBCT scan than in a CT scan. A CT scan
imaging is the low radiation dose is acquired with the patient lying down,
compared to a traditional CT scan. whereas in a CBCT scan, the patient is
sitting up, allowing a more natural head
position. “In a lying position, the load
experienced by the head is not completely
natural. All in all, radiologists should make