Acquisition Phase | Phase Included | Scan Delay | Respiration Phase | Anatomical Coverage |
Non Contrast | Yes | N/A | Inspiration | Carina through the apex of the heart |
Arterial Phase | Yes | Bolus triggered | Inspiration | Carina through the apex of the heart |
Venous Phase | N/A | N/A | N/A | N/A |
Delayed Phase | N/A | N/A | N/A | N/A |
Scan Comments: Aortic valve calcium scoring is routinely performed prior to CTA (see Calcium Score protocol for scan details). All scans are performed using the ALARA principle. 3D post-processing is performed with this protocol. | ||||
Technical Parameters | Parameters |
kVp | 120 |
Effective mAs | Use dose reduction software |
Quality Reference mAs | 320 |
Time (Rotation) | 0.28 sec |
Average Acquisition Time | HR Dependent |
Collimation | 128 x 0.6mm |
Pitch Value | HR Dependent |
Scan Direction | Craniocaudal |
Comments: Dose reduction software is used to reduce patient dose. Both the pitch and the scan time will vary based upon the patient's heart rate. | |
Reconstruction Parameters | Best Diastolic | Best Systolic | Multiphase 0-100% | Thin Data 20% |
Slice Thickness | 0.75 mm | 0.75 mm | 1 mm | 0.75 mm |
Reconstruction Spacing | 0.5 mm | 0.5 mm | 0.8 mm | 0.5 mm |
Reconstruction Algorithm | B26f ASA | B26f ASA | B26f ASA | B26f ASA |
Window Width and Level | 500/100 | 500/100 | 500/100 | 500/100 |
Reconstruction Comments: Images are reconstructed in both best systolic and best diastolic phases. Additional images are reconstructed at 20% and 70% of the R-R interval. A 1.0 mm x 0.8 mm multiphase reconstruction is generated across the entire ECG pulsing range (0-100%). | ||||
Reconstruction Parameters | Thin Data 70% |
Slice Thickness | 0.75 mm |
Reconstruction Spacing | 0.5 mm |
Reconstruction Algorithm | B26f ASA |
Window Width and Level | 500/100 |
Reconstruction Comments: Images are reconstructed in both best systolic and best diastolic phases. Additional images are reconstructed at 20% and 70% of the R-R interval. A 1.0 mm x 0.8 mm multiphase reconstruction is generated across the entire ECG pulsing range (0-100%). | |
Acquisition Phase | Phase Included | Scan Delay | Respiration Phase | Anatomical Coverage |
Non Contrast | N/A | N/A | N/A | N/A |
Arterial Phase | Yes | Bolus triggered | Inspiration | Lung apices through the entire aortic vasculature to include proximal femoral artery |
Venous Phase | N/A | N/A | N/A | N/A |
Delayed Phase | N/A | N/A | N/A | N/A |
Scan Comments: All scans are performed using the ALARA principle. 3D post-processing is performed with this protocol. | ||||
Technical Parameters | Parameters |
kVp | 120 |
Effective mAs | 200 |
Quality Reference mAs | N/A |
Time (Rotation) | 0.28 sec |
Average Acquisition Time | 2-3 sec |
Collimation | 128 x 0.6mm |
Pitch Value | 2.1 |
Scan Direction | Craniocaudal |
Comments:We prefer to keep the pitch lower (less than 2.5) when scanning through the abdomen. This will avoid increased image noise or spiral artifact while still minimizing both cardiac and breathing motion. | |
Reconstruction Parameters | Soft Tissue | Thin Data | Thin Data | Lung |
Slice Thickness | 3 mm | 0.75 mm | 0.75 mm | 3 mm |
Reconstruction Spacing | 3 mm | 0.5 mm | 0.5 mm | 3 mm |
Reconstruction Algorithm | B30f | B20f | I41f (3) | B80f |
Window Width and Level | 410/10 | 410/10 | 410/10 | 1600/-500 |
Reconstruction Comments: When using flash spiral mode, the DFOV is limited by the smaller of the two detector arrays to 33.2cm. This limitation can be overcome by reducing the pitch value to allow a greater DFOV. | ||||
Reconstruction Parameters | Coronal | Sagittal | |
Slice Thickness | 3 mm | 3 mm | |
Reconstruction Spacing | 3 mm | 3 mm | |
Reconstruction Algorithm | B30f | B30f | |
Window Width and Level | 410/10 | 410/10 | |
Reconstruction Comments: When using flash spiral mode, the DFOV is limited by the smaller of the two detector arrays to 33.2cm. This limitation can be overcome by reducing the pitch value to allow a greater DFOV.CT | |||
Contrast Parameters | Parameters |
Contrast Type | Non-ionic |
Contrast Volume | 120 mL |
Saline Flush | 40 mL |
Injection Rate | 4-5 mL/sec |
Oral Contrast | H2O |
Contrast Volume | 1000 mL |
Comments: Bolus tracking is performed off the ascending aorta. | |