chest ct protocols - american association of … ct protocols mannudeep k. kalra, ... • review...
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Chest CT protocols
Mannudeep K. Kalra, MD, DNB
Massachusetts General Hospital
Harvard Medical School
Dianna D. Cody, PhD
M.D. Anderson Cancer Center
Specific principles
• Routine chest CT
• Lung nodule follow up CT
• Review audience sample protocols• Review speaker protocols • Review AAPM protocols
https://aapm.org/pubs/CTProtocolsRoutine chest CT
Institution 1: Routine chest CT protocolLung nodule Follow up
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam coll. (Det. Config.) 24 x 1.2 mm 24 x 1.2 mm
Pitch 0.9 0.9
KV 120 100- 120
Quality Ref. mAs 124 100
Image thickness 5mm 3mm and 1.5 mm
FBP or IRT (kernel) B35 (no Safire or IRIS) B31 (no Safire or IRIS)
Institution 1: Siemens 64 Routine Chest
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam coll. (Det. Config.) 24 x 1.2 mm 64 or 32 x 0.6 mm
Pitch 0.9 1.4
KV 120 120
Quality Ref. mAs 124 100
Image thickness 5mm 5 mm
FBP or IRT (kernel) B35 (no Safire or IRIS) B31 (no Safire or IRIS)
Institution 1: Siemens 64
Routine Chest
Scan type Helical Helical Helical
Scan range Apex to Adrenals Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec 0.5 sec
Beam Coll. (Det. Con) 24 x 1.2 mm 24 x 1.2 mm 64 or 32 x 0.6 mm
Pitch 0.9 0.9 1.4
KV 120 100- 120 120
Quality Ref. mAs 124 100 100
Image thickness 5mm 1.5 & 3 mm 5 mm
FBP or IRT (kernel) B35 (no Safire) B31 (no Safire) B31 (no Safire)
Institution 1: Siemens 64
Routine Chest
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam coll. (Det. Config.) 24 x 1.2 mm 24 x 1.2 mm
Pitch 0.9 0.9
KV 120 120
Quality Ref. mAs 124 124
Image thickness 5mm 5mm
FBP or IRT (kernel) B35 (no Safire or IRIS) B35 (no Safire or IRIS)
Dose: Lung nodule FU = Routine chestInstitution 1: Routine
Siemens 64
Institution 1: Lung nodule
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Lung bases only
Rotation time 0.5 sec 0.5 sec
Beam Coll. (Det. Config.) 24 x 1.2 mm 24 x 1.2 mm
Pitch 0.9 0.9
KV 120 100- 120
Quality Ref. mAs 124 40-60 mAs FIXED
Image thickness 5mm 3mm and 1.5 mm
FBP or IRT (kernel) B35 (no Safire or IRIS) B31 (no Safire or IRIS)
Lung nodule doses must be much lowerInstitution 1: Siemens 64
Institution 2: Routine chest CT protocol
Scan type Helical Helical Helical
Scan range Apex to Adrenals Apex to Adrenals Apex to Adrenals
Rotation time 0.28 sec 0.5 sec 0.5 sec
Beam Coll. (Det. Con) 128 x 0.6 mm 24 x 1.2 mm 64 or 32 x 0.6 mm
Pitch 0.45 0.9 1.4
KV 120 100 - 120 120
Quality Ref. mAs 124 80 65 mAs
Image thickness 5mm 1.5 & 3 mm 5 mm
FBP or IRT (kernel) I 45 & I 50 Safire I 31 (Safire) I31 (Safire)
Siemens Definition 128 Routine Chest CT Institution 2
Institution 3: Doses Routine chest CT = Lung nodule follow up CT
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam Coll. (Det. Config.) 128 * 0.6 128 * 0.6
Pitch 1 1
KV Care KV Care KV
Quality Ref. mAs 170 170
Image thickness 5mm 5mm
FBP or IRT (kernel) B 43 & 80 (no Safire) B 43 & 80 (no Safire)
Routine Chest CT = Lung nodule FU
Institution 3: Routine Institution 3: Lung nodule
(Siemens 128 )
Institution 4: Doses1. Routine chest CT dose: Too high 2. Routine chest CT = Lung nodule FU CT
Routine Chest CT = Lung nodule FU
Scan type Helical (Routine chest) Helical (Lung nodule)
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam Coll. (Det. Config.) 24 x 1.2 mm 24 x 1.2 mm
Pitch 0.75 0.75
KV4 120 120
Quality Ref. mAs 225 225
Image thickness 3mm 3 mm
FBP or IRT (kernel) - -
Institution 4: Siemens 64
Institution 4: Siemens 64Routine Chest CT >> Lung nodule FU
Scan type Helical (Routine chest) Helical (Lung nodule)
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.5 sec
Beam Coll. (Det. Config.) 24 x 1.2 mm 24 x 1.2 mm
Pitch 0.75...higher better motion 0.75…higher better
KV 120………100/120 120……..100/120
Quality Ref. mAs 225 ….…..100 225………40-60
Image thickness 3mm 3 mm
FBP or IRT (kernel) - -
Institution 5: Routine chest CT protocolPhilips
Institution 5: Philips Ingenuity 128Scan type Helical Comments
Scan range Apex to Adrenals
Rotation time 0.5 sec
Beam Coll. (Det. Config.) 64 x 0.625 mm
Pitch Auto 1.1
KV 120
mAs/Image <150 lbs 90; 150-250 lbs 120 lbs >250 150 (no AEC)
No AEC
Image thickness 3 mm and 1.5 mm 3 mm
FBP or IRT (kernel) Filter B Filter B/C
Routine Chest CT
Scan type Helical Helical Helical
Scan range Apex to Adrenals Apex to Adrenals Apex to Adrenals
Rotation time 0.5 sec 0.4 sec 0.4 sec
Beam Coll. (Det. Config.) 64 x 0.625 mm 64 x 0.625 mm 64 x 0.625 mm
Pitch Auto Auto (~ 0.9) 1.1
KV 120 100-120 120
mAs/Image <150 lbs 90; 150-250 lbs 120 lbs >250 150 (no AEC)
100 (Z-DOM)
140(??? Z-DOM)
Image thickness 3 mm and 1.5 mm 3 mm and 1.5 mm 3 mm
FBP or IRT (kernel) Filter B Filter B (iDose 2) Filter B/C
Philips Ingenuity 128Routine Chest CT Institution 5
Institution 6: Philips
Lung nodule FU << Routine chest CT dose
Institution 6: Philips 64 Brilliance
Scan type Helical (Routine chest CT) Helical (Lung nodule FU)
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.4 sec 0.4 sec
Beam Coll. (Det. Config.) 32 X 1.25 mm 32 X 1.25 mm
Pitch 1.1 1.1
KV 120 120
mAs/Image 100 (Z-Dom) 40 (Z-Dom)Image thickness 3 mm and 1.5 mm 3 mm
FBP or IRT (kernel) Filter B Filter B
PHILIPS: ROUTINE CHEST CT: AAPM
GE: Routine chest CT (non ASIR): AAPM
Do not use noise
index for 5mm for thinner
slices and vice versa.
GE:Routine chest
CT (ASIR)
AAPM
GE 64 Routine Chest CT
Scan type Helical Helical
Scan range Apex to Adrenals Apex to Adrenals
Rotation time 0.4 sec 0.4 sec
Beam Coll. (Det. Config.) 64 * 0.625 64 * 0.625
Pitch 1.375 0.984
KV 120 100-120
NI (min – max mA) 13 (100 – 650)16.8 ASIR 50%
20-25 (100-400)30-37 ASIR 40%
Image thickness 5 mm 2.5 and 1.25 mm
FBP or IRT (kernel) Standard Detail
AAPM MGH
Toshiba: Routine chest CT : AAPM (Disclosure)
Special caveats
• Be aggressive with lower kV (<80 kg) or < 30 BMI
• Prefer use of AEC for routine chest CT
• Adapt AEC to clinical indication: Dose for lung nodule FU CT must be lower than routine chest CT doses
• When possible position arms above shoulder
• When not, position arms on the chest rather than by side
Salient points in Chest CT protocols
Lung nodule FU CT: • 100-120 KV
• Fixed low mA or modify AEC
• Apex to lung bases only
• CTDI vol 1.5 - 3 mGy
IRT: 1-2 mGy or lower
Routine chest CT • 100-120 KV (80 kV < 50 kg)
• Always with AEC
• Apex to Adrenal coverage
• Target CTDI vol 3-7 mGyIRT: 2-5 mGy or lower