Refining diagnostic criteria for paediatric bronchiectasis using low-dose CT scan

Area of Science:

• Pediatric Radiology
• Pulmonology
• Medical Imaging

Background:

• Lack of consensus on CT definition of pediatric bronchiectasis.
• Need to establish normal broncho-arterial ratio (BAR) limits in children.
• Investigate the impact of age and general anesthesia on BAR.

Purpose of the Study:

• Determine the upper limit of normal for broncho-arterial ratio (BAR) in children using low-dose CT.
• Evaluate the influence of patient age on BAR.
• Assess the effect of general anesthesia on BAR measurements.

Main Methods:

• Measured 330 broncho-arterial ratios (BAR) in 51 children (0-19 years) via low-dose CT.
• Utilized four measurement methods with three blinded observers.
• Calculated inter-observer reliability, mean BAR, reference ranges, and age correlation.
• Compared BAR in children under general anesthesia versus awake.

Main Results:

• High inter-observer reliability (0.93-0.97) across all measurements.
• Weak positive correlation between age and BAR in awake children (r=0.33, p=0.031).
• Significantly higher BAR under general anesthesia (mean difference 0.13, p=0.004).
• Awake CT showed mean BAR of 0.65 (range 0.42-0.89), with no BAR > 0.9.

Conclusions:

• A broncho-arterial ratio (BAR) > 0.9 in awake children indicates airway widening or bronchiectasis.
• General anesthesia elevates BAR compared to awake CT scans.
• Age-adjusted BAR cut-offs require further investigation due to weak age correlation.