CT Application 3 Chest + Lung Flashcards
role of CT in thorax/lung diseases
- diagnosis
- therapy & management
- emergency role
- research
possible CT thorax/lung applications
non-contrast CT exam = low dose screening + HRCT
contrast CT exam
RT Planning
what phase is used for CT thorax/lung
venous phase
what cannula is used for CT thorax/lung
22G
what rate is used for CT thorax/lung
1.5ml/s
what contrast volume is used for CT thorax/lung
50 ml of IV CT contrast
what phase is used for CT thorax/lung
respiratory gating
what rate is used for CT thorax/lung
1.5ml/s
what cannula is used for CT thorax/lung
22G
what contrast volume is used for CT thorax/lung
50 ml of IV CT Contrast
scan range for routine CT thorax/lung with contrast
lung apex to adrenals
scan range for low dose screening CT thorax/lung or without contrast
lung apex to adrenals or diaphragm
scan range for HRCT
lung apex to diaphragm
scan range for RT planning
whole lung/chest
what should u be mindful of for contrast studies
- previous drug/contrast allergy
- serum creatinine and eGFR
- diabetes mellitus and metformin
- IV access, chest ports, PICC
importance of serum creatinine and eGFR
renal insufficiency
patient position for CT lung/thorax
patient supine/prone with arms above head; head or feet in first
considerations for pediatric CT imaging
isocentre, dose, pitch
recon window for CT thorax/lung
mediastinum, bone, lung
slice thickness & interval for CT thorax/lung
3-5 mm
IV injection rate for CT thorax/lung
50 - 60 mL IVCT contrast @ 1.2 - 2 ml/s
delay timing for CT thorax/lung
1 min after IV injection
reconstruction orientation for CT thorax/lung
axial & coronal (mediastinum & lung window)
parameters for CT thorax/lung
- rehearse breathing
- ACTM & kVP selection when scanning
- thin slice acquisition 1mm for HRCT
rationale for mediastinum algorithm in CT thorax/lung
- smoother images
- good contrast
- maximise SSTM resolution
rationale for lung algorithm in CT thorax/lung
- good contrast
- sharper images
- optimal spatial resolution
WW/WL for mediastinal algorithm
350/40
WW/WL for lung algorithm
1600/-400
WW/WL for bone algorithm
2500/500
2 types of lung cancer
- small cell lung cancer
- non-small cell lung cancer
___ is the most common site of metastasis from primary tumor
lungs
HRCT is important because to determine ___
- differential diagnosis for interstitial lung disease
- detect lung disease in symptomatic patients with normal CXR
interstitial lung disease
diseases that cause lung scarring (fibrosis) and are irreversible
what are ground glass opacities indicative of
- Filling of the alveolar spaces with pus, edema, hemorrhage, inflammation or tumor cells
- thickening interstitium or alveolar walls
lung consolidation
when air that usually fills small airways in lungs is replaced with something else
identifier for centrilobular nodules
dilated and impacted centrilobular bronchioles as indicated by tree-in-bud appearance
what is bronchiectasis
localized bronchial dilatation as seen with
- signet ring sign
- bronchial wall thickening
what is lung atelectasis
collapse / incomplete expansion of pulmonary parenchyma due to alveoli collapse
HRCT is often performed while patient is lying ___
supine
why should patients suspected of lung collapse or atelectasis be imaged supine
opacities are seen more clearly on dependent portions of lungs which are resolved if done prone
indications of HRCT scan technique
detect diseases affecting pulmonary parenchyma and airways
scan range of HRCT scan technique
apex to base of lungs
why is inspiration & expiration done for HRCT scan technique
to recognise air trapping which indicates small airway obstruction
rationale for mediastinum algorithm
- smoother images to maximise SSTM resolution
- good contrast
rationale for lung window & sharp algorithm
- sharper images for better spatial resolution
- good contrast
WW/WL for lung window & sharp
1600/-400
WW/WL for mediastinum algorithm
350/-40
slice thickness & interval for mediastinum algorithm
3/3 mm
slice thickness & interval for lung window algorithm
3/3 mm
slice thickness & interval for lung sharp algorithm
1/10 mm