Last Updated on January 12, 2023 by Mohamad Izwan

Anatomy of Renal

Image taken from www.le.ac.uk

Appearance of CT Renal Images

Examination Overview

Protocol Structure

00_Renal_4Phases (Adult)

  • Topogram
    • Non Contrast (Above diaphragm to the ischial rami)

Bolus Tracking

    • Pre Monitoring
      • (At the level of diaphragm)

Contrast

Monitoring

      • (At the level of diaphragm)
      • Contrast triggering at the abdominal aorta
      • Triggered when achieve 100HU
    • Cortico
        • Cover entire renal
    • Nephro
      • (above diaphragm to the ischial rami)
    • Excretory 5 Minutes 
      • Full abdomen (above diaphragm to the ischial rami)

Topogram

  • Position the patient in head first supine position.
  • Align the patient in Mid-Sagittal plane of the table.
  • Position the transverse laser light beam at the level of patient’s nipple line to start the topogram.
Topo 1
Topo 2
Topo 3

Topogram Parameters

  • Topogram length: 512 mm
  • Slice: 0.6 mm
  • Scanning direction: Craniocoudal
  • Tube position: Top
  • Stop the topogram scanning when the scanning reach / pass over the inferior ischial ramus.

Non Contrast

  • Plan the Scan FOV (SFOV) box at topogram image.
  • Set the top line at the level of above diaphragm.
  • Set the bottom line at the level of inferior ischial ramus.
  • Ensure the lateral line to cover patient’s body outline.
  • Remind the patient before scanning as the breathing instruction will be given.

Scanning Parameters

  • kV: 100 kV
  • mAs: Tube Current Modulation (TCM)
  • Scanning Direction: Craniocaudal
  • Scan Delay: 4 s
  • Slice: 5.0mm
  • Image Comment: Non Contrast
  • Pitch: 0.6
  • Quality Reference mAs : 230

Reconstruction of Non Contrast

Recon 1Recon 2
NameNon Contrast 5.0 B30fNon Contrast 1.0 B20f
Slice Thickness5.0 mm1.0 mm
Increment5.0 mm0.7 mm
KernelB30f medium smoothB20f smooth
WindowingAbdomenAbdomen

Contrast

Type of contrast used:

    • Non-ionic iodinated contrast media
    • 300 I mg/mol

 

Needle Placement Test:

    • Flow Rate: 3.5 ml/sec
    • Volume of Normal Saline: 15 ml

 

Contrast Injection:

    • Volume of Contrast Media:
      • 100 ml (normal body type)
    • Volume of Normal Saline: 50 ml

Injector setup for Normal Body Size

Contrast Normal Saline
Flow rate3.0 ml/sec3.0 ml/sec
Contrast Volume100 ml50 ml

Bolus Tracking

Pre Monitoring

  • Set the scanning line at the level of diaphragm.

Monitoring

  • Ensure the scanning line from Pre-Monitoring is at the level of diaphragm.
  • Ensure the lateral line to cover patient’s body outline.
  • Draw ‘Triggering ROI’ on Abdominal Aorta (left-hand click on Siemens CT console).
  • Set:
    • Delay: 15 seconds
    • Targetted HU to be triggered : 100HU
System will scan several scanning and start corticomedulary phase scanning once the HU reach 100 HU.

Post Contrast Scan Planning

Cortico-Medulary Phase

  • Plan the Scan FOV (SFOV) box at topogram image.
  • Set the top and bottom line to cover entire renal..
  • Ensure the lateral line to cover patient’s body outline.
  • Remind the patient before scanning as the breathing instruction will be given.
  • Delay after triggering: 10 seconds (to enhancement of kidney outer cortex).
Cortico-Medulary Phase

Reconstruction of Cortico-Medulary Phase

Recon 1Recon 2
NameCortico 5.0 B30fCortico 1.0 B20f
Slice Thickness5.0 mm1.0 mm
Increment5.0 mm0.7 mm
KernelB30f medium smoothB20f smooth
WindowingAbdomenAbdomen

Nephrographic Phase

  • Plan the Scan FOV (SFOV) box at topogram image.
  • Set the top line at the upper abdomen.
  • Set the bottom line at inferior ischial rami.
  • Ensure the lateral line to cover patient’s body outline.
  • Remind the patient before scanning as the breathing instruction will be given.
  • Delay after cortico phase: 35 seconds (enhancement of renal parenchyma including medulla).
Nephrographic Phase

Reconstruction of Nephrographic Phase

Recon 1Recon 2
NameNephro 5.0 B30fNephro 1.0 B20f
Slice Thickness5.0 mm1.0 mm
Increment5.0 mm0.7 mm
KernelB30f medium smoothB20f smooth
WindowingAbdomenAbdomen

Excretory 5 Minutes

  • Full abdomen
    • Plan the Scan FOV (SFOV) box at topogram image
    • Set the top line at the level of above diaphragm.
    • Set the bottom line at the level of inferior ischial rami.
    • Remind the patient before scanning as the breathing instruction will be given.
  • Ensure the lateral line to cover patient’s body outline.
Excretory Phase

Reconstruction of Excretory 5 minutes

Recon 1Recon 2
NameExcretory 5min 5.0 B30fExcretory 5min 1.0 B20f
Slice Thickness5.0 mm1.0 mm
Increment5.0 mm0.7 mm
KernelB30f Medium SmoothB20f Smooth
WindowingAbdomenAbdomen

Multiplanar Reconstruction (MPR)

Series of Images Send to PACS

  1. Topogram
  2. Non Contrast 5.0 B30f
  3. Non Contrast 1.0 B20f
  4. Cortico 5.0 B30f
  5. Cortico 1.0 B20f
  6. Nephro 5.0 B30f
  7. Nephro 1.0 B20f
  8. Excretory 5min 5.0 B30f
  9. Excretory 5min 1.0 B20f
  10. Patient Protocol