Changing of the Guard (The Sodium Fluoride Bone Scan) By Karen Wiki Sponsored by Cyclotek

What is 18 F-Sodium Fluoride (NaF) Half Life = 109mins Energy = 511 keV Highly sensitive bone seeking tracer Uptake mechanism resembles 99m Tc MDP Excellent pharmacokinetic characteristics

History  Recognised in the late 60’s Early 70’s 18 F as an excellent tracer for skeletal imaging  Limitations = short half life, high energy level, poor scanner design and availability

99m Tc Bone Scan

PET/CT 18 F NaF

99m Tc BS

Imaging HDPNaF Radioisotope Half Life 6hrs109mins Dose MBq MBq PrepHydration Uptake delay2-4hrs45-60mins Scan duration60 min (WB+SPECT/CT) 30 min (L Spine SPECT/CT) 25 min (WB ± contrast) 10 min (L Spine)

64 SLICE GE Discovery VCT 64 slice GE Infinia Hawkeye SPECT/CT

Combined Total Bone Scan Referrals

Oncology Referrers

Ca Breast

Case Study 1

Case Study 2 99m Tc BS

18 F 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.The SNM Practice Guideline For Sodium 18F-Fluoride PET/CT Bone Scans 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: Apostolova I, Brenner W. Measuring Bone Metabolism with Fluoride PET: Methodological Considerations. PET Clin 2010;5: 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;: Czernin J, Satyamurthy N, Schiepers C. Molecular Mechanisms of Bone 18F- NaF Deposition. JNM 2010;51: Klaus Strodel, Reza Vali. 18F NaF PET/CT Versus Conventional Bone Scanning in the Assessment of Benign Bone Disease. PET Clin Mosci C, Lagaru A. 18F NaF PET/CT in the Assessment of Malignant Bone Disease. PET Clin 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 MDPNaF First-pass clearance ~ 64%Nearly 100% Protein binding50% at 4 hrNegligible % Bone uptake35%-50%50% Urinary excretion 70% after 6 hr50% after 6 hr PET 2012Clin 7 ()

Dose Comparison Chart 99m Tc Bone Scan with SPECT/CT 750MBq (70kg pt) Low Dose CT = 2.5 mSv = 2 mSv Total = 4.5 mSv 18 F NaF Lumbar Spine 200 MBq (70kg pt) Low Dose CT = 4.5 mSv = 3 mSv Total = 7.5 mSv 18 F NaF WB with Diagnostic CT 200 MBq (70kg pt) Diagnostic CT = 4.5 mSv = 13 mSv Total = 17.5 mSv By Dr Alex Mitchell QHP

CT Parameters Scan Type Thick Speed DFOVkVmARecon Type Full Diagnostic CT with Chest Helical Full 0.5s : Auto Max 600 Min 150 Bone+ WB Low Dose CT Helical Full 0.5s : Auto Max 110 Min 40 Bone+

Limitations of 99m Tc Bone Scan Inferior spatial resolution and sensitivity of gamma cameras Longer uptake time Longer scan times SPECT/CT isn’t routinely used

Advantages of 99m Tc 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