Cardiac CT and Cardiac PET 82Rb imaging
Raymond T Endozo
Radiographer
Production of Rubidium-82
Radiotracer
Tracer
Half Life
Production
Method
Rb-82
76 sec
Generator
N-13 Ammonia
9.8 min
Cyclotron
O-15 Water
2.4 min
Cyclotron
110 min
Cyclotron
Fluorine 18 (18F)– flurpiridaz
82 RUBIDIUM
13 N-ammonia
Product
Generator
Cyclotron
Half Life
76 s
9.96 min
Mean Positron n range
2.6 –mm
0.7-mm
Second study
Without delay
30 mins delay
Extraction
50%-60%
80%
PET with the use of short-lived radiopharmaceuticals results in
substantially lower radiation doses to patients than does SPECT
Recommendations for Reducing Radiation Exposure in Myocardial Perfusion Imaging
Cerqueira et al, ASNC information statement, Jnucl Cardiol
Cardiac PET Imaging
• Perfusion studies (Rubidium 82)
– Rest-stress perfusion imaging
– Detection of coronary artery disease and assessing the
progression of coronary artery disease
– May be used in place of or following an equivocal SPECT
study
•
18F-FDG
– Perfusion-metabolism imaging
– Identification of tissue that may recover contractile function
following revascularization techniques
Cardiac pet (Rubidium) optimizes your
clinical environment
•
Faster Imaging , Greater Throughput
•
Ready on Demand ,No waiting on delivery
•
A Positive Imaging Experience for Your Patients and Staff
•
PET is suitable for your patients, including those...
– Result in a suboptimal scan
– Unable to exercise
– EMERGENCY
Good Quality Cardiac PET
•
Count density
-Poor count ( poor intravenous access , inadequate scan duration)
•
Blood Pool Clearance
90s delay
•
Transmission-Emission Misalignment
150s delay
CT Transmission-PET Emission Misalignment
Misregistration Artefact
CT Transmission-PET Emission Alignment
Misregistration Corrected
stress
stress
Rest
Rest
Teaching Point:
Carefully review all CT transmission and PET RB emission images for adequate
registration prior to finalizing the interpretation of the case
List-mode Cardiac PET Acquisition
Dynamic
ECG Gated
LV Function
Absolute Quantification
Flow Quantification : How it is changing MPI
Macrovascular
MPI
Perfusion Defect
Reduced MBF Reserve
(ml/min/g)
Microvascular
FLOW
79/ M
Reassessment CABG 1991 ( 4x graft)
LIMA to LAD,
SVG to RCA , DIAGONAL and OM
Flow Quantification : How it is changing MPI
PET MPI
FUSED CCTA and MPI
STRESS
REST
RCA
LAD
CIRC
MPI
Normal
Ischemia
Mild Ischemia
CT
Occluded Graft-RCA
Occluded Graft -Diag
70 % stenosis Graft
FLOW
0.82
0.59
0.70
FLOW
Coronary Calcium score
Non-contrast-enhanced, ECG gated
Easy-to-perform
No preparation
Radiation dose is minimal
Calcium score
ROI drawn
Measured parameters:
area=A; density=D
CAC score = A x D coefficient
•Originally developed with EBCT- subsequent MDCT
•High reproducibility, low radiation exposure
•Alternative scoring systems
– Volume scoring
– Mass scoring
Calcium score
0
1-400
400-1000
Agaston score
>1000
0 calcium score > 400
Tip of the Iceberg
Calcium > 400 HU
Patterns:
- Speckled (unstable)
- Fragmented
- Diffuse
A
Added value of a Calcium score in patients with Normal PET MPI
B
STRESS
REST
Total Score- 0
Total Score- 950
Cardiac CT Angiography
There are two scanning modes:
Spiral and Axial
• Prospective ECG triggering
• Retrospective ECG gating
Prospective ECG Gating in Action
0010110101010110011011000011101010101010100101001010101010101010101001
0101010101010101010101010101010101010101010100010110101010101001010101
01010101010111010011010101010101010101101001001011001010
0010110101010110011011000011101010101010100101001010101010101010101001
0101010101010101010101010101010101010101010100010110101010101001010101
01010101010111010011010101010101010101101001001011001010
0010110101010110011011000011101010101010100101001010101010101010101001
0101010101010101010101010101010101010101010100010110101010101001010101
01010101010111010011010101010101010101101001001011001010
0010110101010110011011000011101010101010100101001010101010101010101001
0101010101010101010101010101010101010101010100010110101010101001010101
01010101010111010011010101010101010101101001001011001010
Prospective
ECG-Triggered Acquisition
Spiral CT Scanning in Action
001011010101011001101100001110101010101010010100101010101010101
010100101010101010101010101010101010101010101010101000101101010
001011010101011001101100001110101010101010010100101010101010101
101010010101010101010101011101001101010101010101010110100100101
010100101010101010101010101010101010101010101010101000101101010
100101010101010101010101010101110010110101010101010011010101101
101010010101010101010101011101001101010101010101010110100100101
010101110010101011001101010100101011010101010101100100111010101
100101010101010101010101010101110010110101010101010011010101101
010101010101010010110101010110011011000011101010101010100101001
010101110010101011001101010100101011010101010101100100111010101
010101010101010101001010101010101010101010101010101010101010101
010101010101010010110101010110011011000011101010101010100101001
010001011010101010100101010101010101010111010011010101010101010
010101010101010101001010101010101010101010101010101010101010101
101101001001011001010101010101010101010101011100101101010101010
010001011010101010100101010101010101010111010011010101010101010
100110101011010101011100101010110011010101001010110101010101011
101101001001011001010101010101010101010101011100101101010101010
001001110101010101010101010
100110101011010101011100101010110011010101001010110101010101011
001001110101010101010101010
Selected Phase
Retrospective
ECG-Gated Reconstruction
Beta blocker helps image quality
Indications
1.
Heart rate >65 bpm
Contraindications:
1.
Asthma or COPD
2.
AV Block 2nd or 3rd degree
3.
Heart failure
4.
Active Bronchospasm
5.
Allergy to Beta Blocker
6.
Systolic BP <100 mm Hg
1.Promote a more stable heart rate
2.Better chance of freezing the motion of the heart
3.Better dose optimization
Incidental findings abound in
cardiac CT imaging
•
Hiatus hernia
•
Pulmonary embolism
•
lymph nodes
•
Pulmonary nodules
•
Pleural effusion
•
Hepatic cysts
•
Pulmonary infiltrates
•
Interstitial lung disease
Incidental findings in Cardiac CT
imaging
Cardiac PET RB82 and Cardiac CT Protocol
Adenosine
Rb-82
Rb-82
Scout
Cardiac CT
scout
CT-trans
Stress-Dynamic
2 min
Rest –Dynamic
Cal score
Case-1
•
•
•
•
64/F
Atypical chest pain
Irregular heart beat
Hypertensive
CT
MPI
CATH
FUSED-MPI and CT
Case-2
• 43 /M
• Presented with chest pain and ECG
changes.
• ? RCA anomalous origin
MPI
MPI
CATH
CT
Case-3
•
•
•
•
47/M
Chest pain and SOB on exertion.
Hypertension
??Anomolous RCA origin coming off the Main
Pulmonary artery or L PA
• CT Coronary angiogram and perfusion scan
CATH
MPI
CT
Summary
Accuracy/ Speed
Greater Throughput
Positive Experience
Acknowledgements
•
Prof Ashley Groves
•
Prof Peter Ell
•
Dr Jamshed Bomanji
•
Dr.John Dickson
•
Ms Marguerite Meintjes
•
Ms Caroline Towsend