Embryology Flashcards
What do the dorsal and ventral mesenteries divide the intraembryonic coelem into?
What do these go to form?
Left and right sacs
Left - greater sac
Right - lesser sac
Which directions do the ventral and dorsal mesogastrium swing around as the foregut longitudinally rotates?
What do they end up being attached to?
Ventral mesogastrium - right - lesser curve and superior part of duodenum
Dorsal mesogastrium - left - greater curve and inferior aspect of the duodenum
Which ommentum forms which mesentery?
Greater ommentum forms the dorsal mesentery
Name some problems that can arise from abnormal positioning of the tracheosophageal septum.
Proximal blind-end oesophagus
Tracheosophageal fistulas
Name 4 parts of the gut which are secondarily retroperitoneal?
Duodenum
Pancreas
Ascending colon
Descending colon
Which week does physiological herniation occur during?
6th
Give some causes of volvulus.
Malrotation Enlarged colon Pregnancy Abdominal adhesions Hirchsprung’s disease (Congenital intestinal aganglionosis)
Describe the rule of 2s with relation to meckel’s diverticulum.
Give a complication and why it occurs.
2 feet from ileocaecal valve
2% of population
2:1 M:F
Commonly detected in under 2s
Necrosis - ectopic gastric or pancreatic tissue from the foregut causing an inflammatory response.
What is the difference in lymphatic drainage above and below the pectinate line?
Internal iliac above
Superficial inguinal below
Give 3 hindgut abnormalities
Imperforate anus
Anal/anorectal agenesis
Hindgut fistula
Highlight the important parts in the timeline of development of the primary intestinal loop.
4 - appears
6 - herniated
8 - rotates
10 - returns
What occurs in weeks 4 and 7 in relation to pancreatic development?
4 - buds form in the dorsal and ventral mesenteries
7 - fuse
When does recanalisation occur?
Week 8
When does cloacal partitioning occur to form the urorectal septum?
Week 7
When does the buccopharyngeal membrane rupture?
Week 4
