Chest CT protocols Mannudeep K. Kalra, MD, DNB Dianna D. Cody, PhD Massachusetts General Hospital Harvard Medical School 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/ctprotocols Routine chest CT
Institution 1: Routine chest CT protocol Lung nodule Follow up
Routine Chest Institution 1: Siemens 64 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)
Routine Chest Institution 1: Siemens 64 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)
Routine Chest Institution 1: Siemens 64 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)
Dose: Lung nodule FU = Routine chest Institution 1: Routine Siemens 64 Institution 1: Lung nodule 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)
Lung nodule doses must be much lower Institution 1: Siemens 64 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)
Institution 2: Routine chest CT protocol
Routine Chest CT Siemens Definition 128 Institution 2 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)
Institution 3: Doses Routine chest CT = Lung nodule follow up CT
Routine Chest CT = Lung nodule FU Institution 3: Routine (Siemens 128 ) Institution 3: Lung nodule 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)
Institution 4: Doses 1. Routine chest CT dose: Too high 2. Routine chest CT = Lung nodule FU CT
Routine Chest CT = Lung nodule FU Institution 4: Siemens 64 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 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...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 protocol Philips
Routine Chest CT Institution 5: Philips Ingenuity 128 Scan type Helical Comments Scan range Rotation time Beam Coll. (Det. Config.) Apex to Adrenals 0.5 sec 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) Image thickness 3 mm and 1.5 mm 3 mm No AEC FBP or IRT (kernel) Filter B Filter B/C
Routine Chest CT Institution 5 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) Philips Ingenuity 128 100 (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
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 AAPM MGH 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
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 mgy IRT: 2-5 mgy or lower