Medical imaging technique is well advanced today and we are measuring signals from protons level in MRI imaging. But we left behind a error in 2-D measurement in digital X- ray in imaging. This we found out during imaging of Scanogram. In this presentation we are explaining that how we are controlling this error by applying small trick for given plane interest on the digital X-ray Scanogram image.

1. We are from Adyar Cancer Institute Chennai 20. A magnificent
hospital providing state of the art cancer care for over 100,000
patients annually. Celebrating Diamond Jubilee and it has several
firsts.
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2. BY
G. Yogananthem and C. Palanivelu
Cancer Institute, Adyar, Chennai
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3. Medical imaging technique is well advanced today
and we are measuring signals from protons level in
MRI imaging. But we left behind a error in 2-D
measurement in digital X- ray in imaging. This we
found out during imaging of Scanogram. In this
presentation we are explaining that how we are
controlling this error by applying small trick for
given plane interest on the digital X-ray Scanogram
image.

4. 2-D measurement displayed in the Digital X-ray monitor is incorrect
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5. For experimental proof, we developed a wax phantom by keeping 5 lead balls in
plane such that 100 mm distance is kept between the first and fifth lead ball
and the plane is at unknown height from the bottom (the plane of interest).
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6. To prove geometrical error we did the imaging in DX and CT on the
same phantom.
Getting ready CT AP Scout Getting ready DX AP view
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7. CT AP SCOUT VIEW OF THE PHANTOM.
We did AP scout view
of this phantom and
the distance between
the first and fifth lead
ball is measured in
straight line and the
distance is 100 mm.
Due to slit beam
technology there will
not be any geometrical
error. The measured
distance is displayed at
bottom of the monitor.
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8. Digital X-ray AP view
This image is obtained
by AP view of same wax
phantom exposed in
digital X-ray equipment
(Defineium TM 6000)
The measured distance
is 114.2 mm and not
100mm. Due to
geometrical error it is
14.2% more .
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9. scanogram
Scanogram is a special
type of X-ray to
measure the bone
length. In orthopedic
field the Scanogram
are used to measure
real size or length of
the bone. An accurate
and reproducible
assessment of limb
length is required for
successful treatment.

10. Scanogram by using
conventional x-ray
equipment
Geometrical error exists
from conventional X-ray
period and all technical
people are managing it
by keeping lead rulers at
anatomy level and 6 feet
film focal distance. They
measuring the length of
the long bone with the
help of scale projected
over the film or image.

11. Digital X rays are widely used and images on the films are either magnified or
reduced. With the help of workstations and CPU the distance of the required
images are measured and these measurements are inaccurate and discomfort
of taking scanogram started here and we are not able increase FFD beyond 40
inches in table x ray. Because of these reasons many of our orthopedic doctors
are not ready to give up conventional x ray machines.

12. X-Ray Image
The digital medical
X-ray image is
superimposed
image of multiple
planes our body.

13. In digital X-ray equipment, 2D Measurements are inaccurate
since they are measured at a detector level and not at an
anatomical level.
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14. The plane away from the detector will have higher magnification
and plane near to the detector will have least magnification. Tan
angle formula can be used to know correct 2-D measurement.
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15. We have developed a technique , for long bones, where we can get images
without geometrical errors and images are imaged in the film as real size for
the given plane of interest. We can measure the actual length of the given
anatomy with the help of an ordinary measuring ruler on the film itself .
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16. We can call this as real-size imaging, when the virtual ruler readings on the film
matches (coincide) with external ruler for the given plane of interest.
Virtual ruler in the DX image
External ruler readings matches
with the virtual readings
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17. REAL-SIZE IMAGING IN FOUR STEPS BY USING DX
1. DESIGN A LEAD RULER .
2. SELECT THE PLANE OF INTEREST
3. POSITION THE ANATOMY
4. CONTROL ZOOMING ON THE MONITOR
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18. STEP 1. Take a lead ruler and keep it over a processed film from laser
camera as shown below. Measure the width of exposed area of the film
and keep two pointers or markers such that distance between is equal to
the width of the exposing area of the film by omitting the border.
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19. STEP 2. Select the plane of interest by using axial cut of CT image or
lateral CT Scout image.
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20. STEP 3. Position the anatomy (Long bone) parallel to the detector by keeping
pads. Keep the designed lead ruler by side at the level of plane of interest as
shown below and expose. This will help us to get parallel or equal magnification
of long bone and lead ruler and thus we get some control or idea of
magnification of the plane of interest.
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21. STEP 4. Expose the images in landscape format by using laser camera. The
arrows shows the pointer or marker location on the X-ray image. Now we have
to zoom the images in such a way so that both the pointers should touch or
reach the upper and lower limits of film format. Then give print in order to get
real size imaging film from the camera.
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22. This is video demo of zooming of exposed images on
laser film format by using advanced work station.
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23. This is one of the real size imaged film from the camera. We
brought same sample films for display
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24. CT images do not have geometrical error. Matching image width and film
format width we can produce real size imaging on the film by integrating
laser camera and advance work station by feeding simple software. The
following film is an example real size images on the film did manually.
 This CT film shows cerebral
hemorrhage in multiple film
formats. All images are equally
zoomed in real size. The size of
the hematoma will be easily
measured with the help of
ordinary ruler on the film itself
for the treatment and to
comparing with the CT films
repeated later.
 The same method is adopted
to get the multiple real size
images on the same film for
MRI images also.

25. CT guided J needle biopsy is the procedure of taking tissue for study
in operation theater. For this, one lead marker is placed on the body
and one axial cut is taken. Radiologist marks the entry and distance
for the procedure. Only one measurement is on the film. In some
cases surgeon may select another entry at the last minute. In such
cases , real time image will help them to select another entry and
this real time film will help to select and measure on the film itself by
the ruler

26. The below picture shows comparison of different modality images on
single film with real size imaging. The breath of film is matched with
lengths of images. Each modality is best at giving its own details
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28. We applied for patent right for this methodology and it is
under process.

29. WE PROVED 2-D MEASUREMENT IN DX AT DECTECTOR LEVEL
IS IN CORRECT AND KINDLY UPLOAD TAN ANGLE SOFT WARE
SO THAT CUSTERMERS CAN AWARE AT WHAT HEIGHT FROM
DETECTOR ARE MEASURING.
KINDLY INTAGRATE LAZER CAMERA AND ADVANCE WORK
STATITION SO THAT AT SINGLE TOUCH TECHNOLOGIST CAN
GET REAL SIZE IMAGING.

30. We proved, all Digital X ray equipments provide inaccurate
2D measurements, since they are measured at detector level
and not at an anatomy level.
By feeding Tan Angle software, we can compute accurate 2-D
measurements at desired anatomy level.
By matching film size and image size we can produce real size
CT and MRI images on the film.
By matching Screen size and image size we can produce real
size images in PACS monitor also.
we are developing soft wares for all above purpose.
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31. DR.V.SHANTA EXECUTIVE CHAIRMAN
CANCER INSTITUTE, ADYAR, CHENNAI, INDIA
DR.A.V.LAKSHMANAN, ADVISOR
CANCER INSITITUTE
DR.KATHIRESAN, HOD, SURGICAL ONCOLOGY
CANCER INSTITUTE
DR.G .SELVALUXMY , ADDITIONAL DIRECTOR
CANCER INSTITUTE
ALL STAFF MEMBERS, RADIOLOGY
CANCER INSTITUTE

32. NCISRT AND ALL MEMBERS
AND AUDIENCE
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