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These protocols are based on a 128 slice dual source Siemens CT. Some factors may need to be adjusted for a different CT.

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CT - Thorax Seq HRCT

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Children under 5 years of age are often unable to hold their breath long enough to complete an HRCT.
Before an HRCT, practise with the patient their breath holding abilities, make a game of it. Expiration is a hard concept for small children to grasp so use examples that they can understand such as blowing out candles on a cake. Practise this with the child prior to doing the Expiration phase. For children less than 5 years of age a General Anaesthetic will be required. 

Indication - Bronchiectasis
- interstitial lung disease
- asthma
- cystic fibrosis
- infection in immunocompromised patients
- bronchiolitis
- right middle lobe syndrome
- questionable lung disease
Patient Preparation Nil by mouth for 4 hrs if GA req'd
Patient Position - feet first
- supine
- arms raised above head
Scan Area Inspiration - Apices to base of lungs
Expiration - Above Carina to top of diaphragm
kV/Quality ref mAs/
Care Dose 4D on
Care kV semi
100 100 Insp Range:
<2yrs 5mm   feed
>2yrs 10mm feed
Exp Range:
<2yrs 10mm feed
>2yrs 25mm feed       
Detector Collimation  1.0
Slice Thickness 1mm Pitch
IV Contrast Nil
Care Bolus Nil
Scan Delay Nil
Reconstructions 1mm B70s Baby Lung    (Insp and Exp)
2mm B31s Mediastinum (Insp)

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  • Date last published: 30 December 2017
  • Document type: Imaging Protocol
  • Services responsible: Paediatric Radiology

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