Optimizing contrast-enhanced abdominal CT in infants and children using bolus tracking

Area of Science:

• Radiology
• Medical Imaging
• Pediatric Imaging

Background:

• Manual administration of intravenous (IV) contrast material in CT scans leads to unpredictable injection rates.
• Inconsistent contrast delivery can compromise overall scan quality, particularly hepatic enhancement in pediatric abdominal helical CT.

Purpose of the Study:

• To evaluate the impact of bolus tracking on abdominal helical CT scan quality in children.
• Specifically, to assess its effect on hepatic enhancement when contrast media is manually administered.

Main Methods:

• A comparative study involving 33 abdominal helical CT scans from 29 children using bolus tracking and 22 scans from 21 children without bolus tracking.
• Both groups received contrast material via manual injection.
• Qualitative assessment of organ/vessel enhancement and scan appearance, alongside quantitative region-of-interest analysis at three anatomic levels.

Main Results:

• Bolus tracking significantly increased hepatic enhancement at superior (48.5 vs. 28.6 HU), middle (47.9 vs. 32.3 HU), and inferior (48.2 vs. 36.5 HU) levels (p < .001).
• The bolus tracking group showed more consistent enhancement across hepatic levels (p > .50) compared to the control group (p < .02).
• Improved scanning during the nephrographic phase (89% vs. 59%, p = .02) and reduced inferior vena cava flow artifact (3% vs. 27%, p = .01) were observed with bolus tracking.

Conclusions:

• Bolus tracking enhances contrast delivery in pediatric abdominal helical CT scans with manual contrast administration.
• This technique leads to significantly improved hepatic enhancement and overall scan quality in children.
• Bolus tracking is beneficial for optimizing CT imaging when injection rates are unpredictable.