Neutral Contrast Agents for CT Enterography

Standard Neutral Contrast Options

The American College of Radiology recommends using water as a neutral contrast agent for CT enterography 1
The American College of Radiology recommends using methylcellulose suspensions as a neutral contrast agent for CT enterography 2
The ACR Appropriateness Criteria explicitly identify neutral contrast agents, including water, as acceptable for CT enterography, allowing optimal visualization of mucosal hyperenhancement against the hypointense luminal contrast 1, 2, 3

Patients should ingest 1,000-2,000 mL of neutral contrast over 45-60 minutes before scanning, with imaging typically performed at 60 minutes, as recommended by the American College of Radiology 1, 3
The American College of Radiology guidelines for pediatric patients specify 900-1,500 mL of neutral contrast based on patient weight 4

The American College of Radiology states that positive oral contrast agents must be avoided in CT enterography because they obscure mucosal hyperenhancement and active hemorrhage 5, 6
The American College of Radiology recommends that intravenous contrast administration is mandatory to visualize enhancing lesions and inflammatory changes against the neutral intraluminal contrast 1, 3, 6

Patients should fast from solids for 4-6 hours before CT enterography, as recommended by the American College of Radiology 4

The American College of Radiology recommends avoiding oral phosphate-containing preparations in patients with GFR <60 mL/min/1.73 m² due to risk of phosphate nephropathy 7

The American College of Radiology identifies low w/v barium solutions as a neutral option for CT enterography 8

The Society of Abdominal Radiology recommends administering 900 mL of neutral contrast in divided doses over 45-60 minutes for CT enterography 9, 10
The American College of Radiology guidelines specify administering 1,300-1,800 mL of neutral contrast over 30-60 minutes for optimal distension 11, 12

Neutral contrast allows visualization of enhancing bowel wall against hypointense luminal contents, as recommended by the American College of Radiology 8
The contrast-enhanced phase should be acquired 50-70 seconds after IV injection, between enteric and portal venous phases, as suggested by the Society of Abdominal Radiology 9, 10

The American College of Radiology advises against using standard positive oral contrast for CT enterography, as it obscures mucosal enhancement patterns, with guidelines supported by 11, 12