| Author | Number of specimens | Duodenal plug | Crown-Rump Length | Explanation for Atresia |
| Tandler, 1902 [1] | 7 + 4 descriptions | Yes | 12.5 to 15 mm | Persistence of epithelial plug |
| Lynn & Espinas, 1959 [5] | 89 | Plugging and/or vacuolation in less than one third of cases | 7 to 59 mm | Epithelial proliferation simultaneously in the colon. |
| Moutsouris, 1966 [6] | 70 | No complete occlusion | 7 to 40 mm | Never complete occlusion, always vacuolation |
| Boyden, et al. 1967 [2] | 4 | Epithelium fills or fills partially the lumen | 9.5 to 25 mm | Induction of atresia due to impaired formation of the pancreaticobiliary junction |