1. By: Sara al-lithey, Nora Alanazi
Chest CT
By: Sara al-lithey, Nora Alanazi

2. Outline: Chest CT. Indications. Contraindications. Chest CT protocols.
- HRCT protocol.
- Pathology protocol.
- Pulmonary Embolism.
Patient after care .

3. Chest CT scanning
is a noninvasive medical test that helps physicians diagnose and treat medical conditions.
CT scan is better for chest
CT it show many different types of tissue, including the lungs, heart, bones, soft tissues, muscle and blood vessels in short time.

4. Indication Chest pain. Chest trauma. Infection.
Intra-thoracic bleeding
Pulmonary embolism.
Pneumonia.
Suspected tumor or mass.
Assessment of interstitial lung disease
Minor fibrosis

5. Contraindication
Pregnancy.
Hypersensitivity to iodinated contrast media( if contrast is used).
Renal failure.
Heart disorder

6. Technique High Resolution CT HRCT Pathology or Routine C+
Pulmonary Embolism PE

7. 1- HRCT Without contrast.
High kV, mAs & thin slices to produces a high spatial resolution and anatomic detail
No preparation
Sedation if needed.

8. Patient position Supine, in the center of the table
Feet first in the gantry (child, head first to see the chest movement during the breathing after the sedation).
Table height
The arms are above the head.
The external laser liner in the chine.
Scout Images:
PA : plane 180º
Lat : plane 90º

9. Procedure Inspiration Expiration Prone
To cover from the apex to the base of the lung
Inspiration
From the Aorta down to the lower lung
Expiration
To check the plural effusion
Prone

10. Scan parameters: Window level window Soft tissue 35 500 Standard
Recon. Algorithm
FOV
pitch
Recon
Slice thick
Scan delay MA KV
Type of scan
standard
lung
Large
30-40
1.375 speed 27.5
1.25 ×5
2.5
×2.5
0.7 sec
Auto M.A
120
Spiral (axial) Inspiration
Lung _
1.25 ×10
Auto
m.A
Axial
Spiral
Expiration & Prone
Window
level
window
Soft tissue 35
500
Standard
spiral 1
Lung widow
- 300
1500
spiral 2 & 3

11. Reformatting: sagittal & coronal
Note:
FOV is as small as possible while still including all of the soft tissue and the upper abdominal part (to check the metastasis).

12. 2- Pathology (C+) Preparation: NPO 3-4 hours before the procedure.
Not allergic or asthmatic.
Renal function test normal
1 week inpatient.
3 month diabetic patient
6 month non diabetic patient.
Canulla in the Rt arm, size 18, 20 Gag.
Sedation if needed

13. Procedure Inspiration technique: As HRCT Patient position: As HRCT
IV Contrast media:
Omnipaque
Xenetix
Adult : 300
Child: 250

14. Contrast media The injector machine Hand injection
Adult Child FR 5ml/sec 5ml/sec V 100 ml Weight × 2
Time delay
sec
C. in the Aorta

15. Axial & Sagittal – Soft window
Scan parameters & Window : as Inspiration HRCT
2nd Reconstruction: ×1.25
Axial & Sagittal – Soft window

18. 3- Pulmonary Embolism scan
Fast helical CT scanning to visualization of the pulmonary vessels and lung parenchyma during the injection of a CM to detect any obstruction.
Optimal contrast should be in the pulmonary arteries, but not in the pulmonary veins.
Patient Preparation & position: As 2nd tech.

19. Main thing: calculate the contrast time that start from the injection until it will enter in the
main pulmonary artery
Two ways to calculate the timing:
Smart Prep
Bolus timing
Then selected in the computer.

20. A- Smart Prep In case if: The heart rate abnormal (above 110-140)
Obese patient (above 110 Kg).

21. Window Scan parameters Level window 100 800 soft tissue spiral 1 - 300
Recon. Alga.
FOV
pitch
Recon.
S.T
sec
Scan delay MA KV
Type of scan
standard
lung
large
1.375 speed 27.5
2.5 × 2.5
1.25 ×0.6
0.7 sec
auto
Helical spiral
Window
Level
window
100
800
soft tissue
spiral 1
- 300
1500
lung window
spiral 2

22. b- Bolus Timing In case if the heart rate normal (70-90) Procedure
PA scout (to localize the pulmonary trunk).
FOV only in the bifurcation of the trachea and take CT images.

23. Select 20 images in the same location
Give 20 ml IV CM (FR 5 ml/ sec)
Start the CM in the same time of the exposure
wait the image to review.
From the 20 images, select the good image with the good contrast in the Main Pulmonary artery.
Time delayed calculation:
image number × 2 = sec

24. Then do the normal image from down- up with same before and fixed the scan time manually.
This graph shows that the contrast injected into the vein reached the pulmonary trunk in 8 seconds.

25. I.V. Contrast Smart Prep: Adult: 100 ml – 5 ml/ sec
Bolus timing: Scan time × 5 = volume
The bolus timing is Better than the Smart Prep
Less C. dose, so there is chance to repeat the scan again if there is any mistake ( the max dose is 100 ml/ day).

26. Reformatting Sagittal Coronal Both oblique
Maximal intensity projection (MIP)

27. After care Pt. can eat or drink as normal.
Drink fluids to flush the contrast.
Bandaged contrast injection site.
Watch the patient for adverse contrast reactions.