GE Healthcare
About GE Healthcare
GE Healthcare provides transformational
medical technologies and services to
meet the demand for increased access,
enhanced quality and more affordable
healthcare around the world. GE (NYSE:
GE) works on things that matter great
people and technologies taking on tough
challenges. From medical imaging,
software & IT, patient monitoring
and diagnostics to drug discovery,
biopharmaceutical manufacturing
technologies and performance
improvement solutions, GE Healthcare
helps medical professionals deliver great
healthcare to their patients. For more
information about GE Healthcare, visit
our website at www.gehealthcare.com.
Corporate Headquarters
GE Healthcare
540 W Northwest Highway
Barrington, IL 60010-3076
USA
European Headquarters
GE Healthcare
283 rue de la Minière
78530 BUC
France
Tel: +1 847-277-5000 or
1 800-437-1171 or
1 800-682-5327
Fax: +1 847-277-5240
GE Healthcare
@GEHealthcare
GE Healthcare
GE Healthcare
Dosimetry Toolkit
“
Our plan is to evaluate “Dosimetry Toolkit”
as a quantitative tool in a the follow-up
of thyroid cancer patients after iodine 131
”
Pr. Martin Schlumberger,
MD, PhD
Head, Imaging Dpt.
Gustave Roussy Hospital
Villejuif, France
GE imagination at work
©2014 General Electric Company — All rights reserved. *Trademark of General Electric Company.
GE, the GE Monogram and imagination at work are trademarks of General Electric Company. GE Healthcare, a division of General Electric Company.
** All third party trademarks are the property of their respective owner.
The clinical cases are displayed for educational purposes only and for the benefit of healthcare students and professionals
JB24623FR
Marcel Ricard, PhD
Medical Physicist
Nuclear Medicine Dpt.
Gustave Roussy Hospital
Villejuif, France
Overview of the site
Gustave Roussy is an Oncology
comprehensive center which
missions are to treat cancer
patients, develop new
therapeutic procedures and
disseminate knowledge in
medical and scientific French
and international communities.
Research and teaching are
closely linked. Based on its
expertise and advanced medical
practices, GR is considered as a
reference center in France but
also internationally. Gustave
Roussy relies on its specific
therapeutic innovations,
development of personalized
medicine, quality and safety of
care, always placing the patient
at the center of its missions.
Equipment
The site is equipped with a Discovery*
PET/CT 690, a GE Discovery NM/CT 670
and a Discovery 630. Four Xeleris system
and 3 AW systems complete this
equipment.
Dosimetry Toolkit
The uptake of iodine 131 measured
during radioactive iodine treatment
of differentiated thyroid cancer, is a
powerful medical indicator of efficacy.
Recent technological developments,
as hybrid SPECT/CT machines, are
designed to improve the reliability of
quantification. Regarding these new
opportunities, Pr Schlumberger became
very interested to evaluate the clinical
value of a 3D segmentation tool such
as Dosimetry Toolkit.
As Dosimetry Toolkit is dependent on
the performance of the gamma camera
device, a calibration step is mandatory.
All calibrations have been implemented
using a high-energy collimator mounted
on NM/CT 670 equipped with 5/8" crystal.
Images have been reconstructed after
attenuation and scatter corrections
using OSEM algorithm (2 iterations,
10 subsets). We performed calibration
with three different phantoms.
The cylindrical Deluxe Jaszczak Phantom**
was used to define de threshold level
using refillable spheres. The
anthropomorphic Livermore Laboratory
phantom was useful to consider realistic
situation mimicking normal thyroid
remnants or lymph nodes. Finally the
Anthropomorphic Torso Phantom**
allowed taking into account the spread of
radioactivity in case of lung involvement.
Following calibration two distinct
sensitivity factors (counts/MBq/s) were
specified one for soft tissues and one
for lungs.
After implementation and calibration
of Dosimetry Toolkit, and our phantombased study, in our experience an
accuracy of about 20 % may be
reasonably achieved. This value is
in good agreement with clinical
requirements. Based on our phantom
study, in terms of sensitivity, uptakes as
low as 0.01 % of the administered activity
can be estimated*. Individual results
in the clinical arena may vary.
Clinical application
Uptake measurements are usually
performed 2 or 3 days after iodine 131
administration of 1100 MBq or 3700 MBq
for patients who have been prepared
with either Thyrogen or withdrawal.
Image segmentation was performed
both from nuclear medicine images or
CT-scans, depending on the type of
uptake e.g. lymph node or lung
involvement. In all cases, the tools were
found easy to use except for images
with a poor signal to noise ratio. In that
situation the analysis of the images must
be entrusted to an experienced observer.
Dosimetry Toolkit has demonstrated its
usefulness in the quantification of SPECT/
CT images and in the measurement of
uptakes following a 131 iodine
administration. It has a potential for in
vivo data when dosimetric studies are
planned. However, actual clinical studies
need to be performed.
3D SPECT
Segmentation done
SPECT images
Quantification on segmented images
These first evaluations showed that Dosimetry Toolkit can help in I131
quantification after treatment of thyroid cancer patients. Tools are compatible
with medical requirements when an accuracy of +/- 20% is generally considered
as enough accurate to allow the monitoring of thyroid cancer patients 1.
1. Author’s conclusions are solely based on their scientific study and must be evaluated by an medically qualified reader. GE does not necessarily endorse nor support any conclusions or
recommendations contained in author’s findings.
GE Healthcare
About GE Healthcare
GE Healthcare provides transformational
medical technologies and services to
meet the demand for increased access,
enhanced quality and more affordable
healthcare around the world. GE (NYSE:
GE) works on things that matter great
people and technologies taking on tough
challenges. From medical imaging,
software & IT, patient monitoring
and diagnostics to drug discovery,
biopharmaceutical manufacturing
technologies and performance
improvement solutions, GE Healthcare
helps medical professionals deliver great
healthcare to their patients. For more
information about GE Healthcare, visit
our website at www.gehealthcare.com.
Corporate Headquarters
GE Healthcare
540 W Northwest Highway
Barrington, IL 60010-3076
USA
European Headquarters
GE Healthcare
283 rue de la Minière
78530 BUC
France
Tel: +1 847-277-5000 or
1 800-437-1171 or
1 800-682-5327
Fax: +1 847-277-5240
GE Healthcare
@GEHealthcare
GE Healthcare
GE Healthcare
Dosimetry Toolkit
“
Our plan is to evaluate “Dosimetry Toolkit”
as a quantitative tool in a the follow-up
of thyroid cancer patients after iodine 131
”
Pr. Martin Schlumberger,
MD, PhD
Head, Imaging Dpt.
Gustave Roussy Hospital
Villejuif, France
GE imagination at work
©2014 General Electric Company — All rights reserved. *Trademark of General Electric Company.
GE, the GE Monogram and imagination at work are trademarks of General Electric Company. GE Healthcare, a division of General Electric Company.
** All third party trademarks are the property of their respective owner.
The clinical cases are displayed for educational purposes only and for the benefit of healthcare students and professionals
JB24623FR
Marcel Ricard, PhD
Medical Physicist
Nuclear Medicine Dpt.
Gustave Roussy Hospital
Villejuif, France