Changing of the
Guard
(The Sodium Fluoride Bone Scan)
By Karen Wiki
Sponsored by Cyclotek
What is
18F-Sodium Fluoride (NaF)
• Half Life = 109mins
• Energy = 511 keV
• Highly sensitive bone seeking tracer
• Uptake mechanism resembles 99mTc
MDP
• Excellent pharmacokinetic characteristics
History
 Recognised in the
late 60’s Early 70’s
18F as an excellent
tracer for skeletal
imaging
 Limitations = short
half life, high energy
level, poor scanner
design and
availability
99mTc
Bone Scan
PET/CT
18F
NaF
99mTc
BS
18F
NaF
Imaging
HDP
NaF
6hrs
109mins
740-900 MBq
150-250 MBq
Hydration
Hydration
Uptake delay
2-4hrs
45-60mins
Scan duration
60 min
(WB+SPECT/CT)
25 min (WB ±
contrast)
30 min
(L Spine
SPECT/CT)
10 min (L Spine)
Radioisotope
Half Life
Dose
Prep
GE Infinia Hawkeye
SPECT/CT
GE Discovery VCT
64 slice
64 SLICE
Combined Total Bone Scan Referrals
NaF
Tc BS
2010
2011
2012
2013
Oncology Referrers
NaF
Tc BS
2010
2011
2012
2013
Ca Breast
NaF
Tc BS
2010
2011
2012
2013
Case Study 1
Case Study 2
99mTc
BS
18F
NaF
18F
NaF
Advantages of NaF PET/CT
•
•
•
•
•
•
Superior pharmacokinetics
Sensitive for lytic lesions
Better resolution and sensitivity
Routine tomographic data
Routine use of CT improves specificity
Shorter total examination time
• One stop shop
References
1.
2.
3.
4.
5.
6.
7.
8.
The SNM Practice Guideline For Sodium 18F-Fluoride PET/CT Bone Scans
1.1
Grant FD, Fahey FH, Packard AB, Davis RT, Alvai A, and Treves ST. Skeletal
PET with 18-Fluoride: Applying New Technology to an Old Tracer. JNM
2008;49:68-78.
Apostolova I, Brenner W. Measuring Bone Metabolism with Fluoride PET:
Methodological Considerations. PET Clin 2010;5:247-257.
Abikhzer G, Kennedy J. 18F NaF PET/CT and conventional Bone Scanning in
Routine Clinical Practice; Compartive Analysis of Tracers, Clinical Acquisition
Protocols, and Performance Indices. PET Clin 2012;:315-328.
Czernin J, Satyamurthy N, Schiepers C. Molecular Mechanisms of Bone 18FNaF Deposition. JNM 2010;51:1826-1829
Klaus Strodel, Reza Vali. 18F NaF PET/CT Versus Conventional Bone
Scanning in the Assessment of Benign Bone Disease. PET Clin 2012
Mosci C, Lagaru A. 18F NaF PET/CT in the Assessment of Malignant Bone
Disease. PET Clin 2012
Southern Cross Health Insurance Eligibility criteria PET/CT
Breast Cancer
• Initial Staging in high risk Breast Cancer(Clinical Stage
lllA or higher) or
• Initial Staging in Clinical l-llB Breast Cancer with
symptoms of bone pain or elevated alkaline phosphatase
levels suggesting the presence of bone metastases
• Restaging of all stage disease with symptoms of bone
pain or elevated alkaline phosphatase levels strongly
suggestive of the presence of bone metastases
Southern Cross Health Insurance
Comparison of pharmacokinetic properties
MDP
NaF
~ 64%
Nearly 100%
Protein binding
50% at 4 hr
Negligible
% Bone uptake
35%-50%
50%
70% after 6 hr
50% after 6 hr
First-pass
clearance
Urinary
excretion
PET 2012Clin 7 () 315-328
Dose Comparison Chart
99mTc
Bone Scan
with SPECT/CT
750MBq (70kg pt) = 2.5 mSv
Low Dose CT
= 2 mSv
Total = 4.5 mSv
18F
NaF Lumbar
Spine
200 MBq (70kg pt) = 4.5 mSv
Low Dose CT
= 3 mSv
Total = 7.5 mSv
18F
NaF WB with
Diagnostic CT
200 MBq (70kg pt) = 4.5 mSv
Diagnostic CT
= 13 mSv
Total = 17.5 mSv
By Dr Alex Mitchell QHP
CT Parameters
Scan
Type
Thick DFOV
Speed
Full
Diagnostic
CT with
Chest
Helical
Full
0.5s
3.75
WB
Low Dose
CT
Helical
Full
0.5s
3.75
kV
Recon
Type
70
120
Auto
Max 600
Min 150
Bone+
70
120
Auto
Max 110
Min 40
Bone+
0.984:1
0.984:1
mA
Limitations of 99mTc Bone Scan
• Inferior spatial resolution and
sensitivity of gamma cameras
• Longer uptake time
• Longer scan times
• SPECT/CT isn’t routinely used
Advantages of 99mTc Bone Scan
•
•
•
•
•
Wide availability
Generator produced/daily elution
Longer physical half-life
Flow, blood pool and delayed
Lower radiation dose (0.0057mSv/MBq)
Limitations of NaF PET/CT
•
•
•
•
Cyclotron produced
Availability
Higher radiation exposure
Lack of flow and blood pool
capabilities