Table 3. Comparison of Methods Used to Assess Gastric Emptying
Scintigraphya
Mechanisms of gastric emptying
Validation Studies Radiation exposure
Reproducibility (CV%)c Limitations for testing
Assessment of antral contractility
Assessment of small bowel and colonic transit
c Antral motor activity
Extensive Yes
inter – 24% intra – 12%
Pregnancy Feasible Yes
Wireless Motility Capsuleb
Antral motor activity and migrating motor complex activity
Modest No
Not studied Obstruction Yes Yes
a Obtain scans at 1, 2, and 4 hours to accurately estimate gastric emptying by scintigraphy. b
Using a 5 h cutoff for gastric emptying, capsule discriminates between normal and delayed gastric emptying with a sensitivity of 0.87 and a specificity of 0.92.
CV% - percentage coefficient of variation. Inter and intra – inter- and intra-individual coefficient of variation.
Table 4. Strengths and Limitations of Imaging Techniques for Measuring Gastric Volumes Strengths
Technique SPECT
Ultrasound MRI Limitations
• Extensively validated • Can be combined with scintigraphy to assess gastric emptying
• No radiation • Can also assess antral contractility and pyloric flow
• No radiation • Validated • Can also assess gastric air and fluid volumes, contractility, secretion, and emptying
• Radiation exposure • Limited temporal and spatial resolution
• Presence of air may limit visualization, especially in the fundus
• Highly operator-dependent
• Expense and limited availability
