RadteraGastric Emptying Study (Tc-99m Sulfur Colloid Solid Meal)
NM+ ContrastAbdomen & Pelvis
Indications
- Suspected gastroparesis (diabetic, idiopathic, post-surgical)
- Dumping syndrome / rapid gastric emptying
- Unexplained nausea, vomiting, early satiety, bloating
Patient prep
- Fast at least 4-6 hours (overnight preferred)
- Hold medications affecting motility 48-72 h (prokinetics e.g. metoclopramide; opioids; anticholinergics) per referring physician
- Diabetics: check blood glucose; hyperglycemia (>200-275 mg/dL) delays emptying — reschedule or document
- No smoking on study day
Contrast
AgentTc-99m sulfur colloid bound to standardized solid meal (egg-white meal: 4 oz liquid egg whites, 2 slices toast, jam, water)
RouteOral (with labeled meal)
Dose0.5-1 mCi (18.5-37 MBq) mixed into egg whites
TimingImaging at 0 (immediately after meal), 1, 2, and 4 hours
Technique
- LEHR collimator, 140 keV
- Anterior and posterior static images at each time point (geometric mean to correct for depth)
- Patient upright/sitting or standing; consistent positioning between time points
- Standardized meal and 4-hour protocol essential for normal values
Series / Sequences
| # | Series / Sequence | Plane | Notes |
|---|---|---|---|
| 1 | Immediate (0 h) | Anterior + posterior | Baseline 100% retention reference |
| 2 | 1 hour | Anterior + posterior | Geometric mean % retained |
| 3 | 2 hours | Anterior + posterior | Normal <60% retained at 2 h |
| 4 | 4 hours | Anterior + posterior | Normal <10% retained at 4 h; >10% = gastroparesis |
Key points
- Standardized SNMMI/ANMS protocol: low-fat egg-white meal, 4-hour acquisition with established normal values (>10% retained at 4 h = delayed)
- Hyperglycemia delays gastric emptying — verify glucose in diabetics before starting
- Hold prokinetics and opioids that alter motility
- Use geometric mean of anterior/posterior to correct for anterior-posterior migration of food
References
• SNMMI Procedure Guideline for Adult Solid-Meal Gastric-Emptying Study 3.0 (J Nucl Med Technol 2009;37:196)
• ANMS/SNMMI consensus on gastric emptying scintigraphy
• Radiopaedia: Gastric emptying scintigraphy link
• ANMS/SNMMI consensus on gastric emptying scintigraphy
• Radiopaedia: Gastric emptying scintigraphy link
Source: Researched — verify against your institution
Reference template — verify and adapt to your scanner, vendor and institution before clinical use. Not a substitute for clinical judgment.