Step & Shoot (or AXIAL) scans are done when the BMI is less than 32 and/or heart rate is below 70
| History: | Evaluate coronary arteries or anomalies |
| Surview: | Dual: Sternal notch to mid-kidneys |
| Contrast: | Omnipaque 350 -6mL/sec for 75mL, then 5mL/sec for 40mL 50/50 mix saline/contrast, then 5mL/sec for 50mL saline flush |
| Gated: | Prospective(Axial)- 78% tagging |
| Tracker: | 1 cm below carina |
| ROI : | Descending Aorta |
| HU : | 140 |
| BREATHING INSTRUCTIONS: | Practicing and coaching the breath hold is also extremely important and should be performed on inspiration. |
Note: REMINDERS FOR ALL GATED STUDIES:
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| Ca Score: | Must be done at 120 kVp, mAs can not exceed 160. DO NOT CHANGE kVp FOR CALCIUM SCORE Use 100 kVp if BMI is <30 Adjust mAs to patients size |
| CTA: | Scan superior to inferior for both Ca Score and CTA. Start at the level of the main pulmonary bifurcation to bottom the of heart. Scan should be centered over the heart. CARDIAC DOSE RIGHT, "Handle Irregularities on line", and Phase Tolerance should be on. Set phase tolerance to 5. These parameters are found under the heart icon. It is important to choose an appropriate mAs according to the patient's size. |
| Parameter Type : | CA SCORE | CTA |
| Thick/Incr. | 2.5 @ 25 | .9 @ .45 |
| Kvp | 120 | 120 |
| mAs | 80-160 | min. 180 |
| Resolution | Std. | Detailed |
| Collimation | 32 x 0.625 | 128x0.625 |
| Pitch | N/A | N/A |
| Rotation Time | 0.33 | 0.27 |
| Scan FOV | 250 | 250 |
| Filter | CB | XCB |
| HU | N/A | 140 |
| iDose4 Level | iD-3 | iD-3 |
| Scan Delay | N/A | 5 |
| Tagging | 75% | 78% |
| Thin Section Recons. | .9 @ .45 | with EDGE CORRECTION |
***PHASE TOLERANCE SHOULD BE SET @ 5 | ||
| Post Processing | 73% and 83% with EDGE CORRECTION |
| Archiving | Calcium Score CTA Recon Phases |
Courtesy of the University of Maryland