Table 1.
Nonneoplastic gallbladder polyps
| Nonneoplastic polyp | Mean size (mm) | Radiologic finding | Pathologic finding | Number (single/multiple, %) | Frequency (%) |
|---|---|---|---|---|---|
| Cholesterol polyp | <10 | US: hyperechoic polyp, typically round shape with “ball on the wall” sign | Grossly, yellow appearance, microscopically, distinctive cauliflower configuration and cholesterol-laden macrophages | Single (36.4) | 60−90 |
| Multiple (63.6) | |||||
| Inflammatory polyp | <10 | US: variable echogenicity (iso-, hypo-, or hyper-) | Pseudopapillary fronds with reactive mucosal changes, inflammation, and increased vascularity | Usually multiple | 10 |
| Adenomyoma | NA | US: wall thickening with ‘‘comet tail’’ | Trabeculated appearance cystic dilation of glandular spaces (Rokitansky-Aschoff sinuses) and smooth muscle hypertrophy | Usually single | 25−40 |
| MRI: ‘‘pearl necklace” sign of by fluid containing diverticula | |||||
| Fibromyoglandular polyp | 4.3 (2−13) | NA | Broad-based polyps | Single (56) | 48 |
| Lobular units of small glands | Multiple (44) | ||||
| Fibroblastic and/or muscular stroma | |||||
| Hamartoma | NA | NA | NA | NA | Very rare |
US, ultrasonography; MRI, magnetic resonance imaging; NA, not available.