Development and teratology of digestive system. Anna Mac Gillavry 03.03.2025 • Primitive gut formation results from the lateral folding of the embryo • Foregut, midgut and hindgut • (Yolk sac, allantois) Hindgut T.W. Sadler, Langman's medical embryology, 14th edition Diaphragm Bare area of liver Falciform ligament Umbilical vein (carries oxygenated blood to embryo) Extraembryonic coelom Lesser omentum I_ Hepatoduodenal ligament Hepatogastric ligament , Dorsal mesogastrium Midgut loop Dorsal pancreatic bud Celiac artery — Gallbladder Dorsal aorta Superior mesenteric artery Free edge of ventral mesogastrium Peritoneal cavity (former intraembryonic coelom) Inferior mesenteric artery K. Moor, Before we are born, 10th edition Esophagus 4th week Foregut Tracheoesophageal septum Respiratory diverticulum -— Pharynx — - Trachea Lung buds I Esophagus T.W. Sadler, Langman's medical embryology, 14th edition Stomach Two rounds of rotation: 1. 90° clockwise along the longitudinal axis Dorsal surface Posterior surface Right-vagus nerve Right LLeft border vagus nerve Posterior gastric nerve Left border Anterior gastric nerve Ventral surface Anterior surface Desarrollo de los Órganos Abdominales I Concise Medical Knowledge (lecturio.com) Dorsal mesogastrium Small vacuoles Stomach Lesser omentum T.W. Sadler, Langman's medical embryology, 14th edition Stomach Omental bursa Greater omentum-*^ Omental bursa Peritoneum of posterior abdominal wall — Pancreas Duodenum Mesentery of transverse colon Greater omentum — Small intestinal Iood B T.W. Sadler, Langman's medical embryology, 14th edition Esophagus: - esophageal atresia and/or tracheoesophageal fistula -polyhydramnios - esophageal stenosis - congenital hiatal hernia Trachea Bifurcation ! Proximal blind-By* end part of esophagus Tracheoesophageal fistula Distal part of esophagus B Communication ĺ of esophagus \ with trachea Stomach: - pyloric stenosis (1 in 150 males, 1 in 750 females) - develops during fetal life, however, can develop as a result of postnatal exposure (e.g. erythromycin) T.W. Sadler, Langman's medical embryology, 14th edition Development of the liver and pancreas Liver bud - Stomach Gallbladder - Ventral pancreatic bud Dorsal pancreatic bud Hepatic duct Cystic duct Ventral B pancreas Accessory pancreatic duct Minor papilla , / *v. Ventral Major papilla' pancreatic duct Dorsal pancreatic duct Bile Dorsal pancreas duct B Main pancreatic duct Uncinate process ^ Ventral pancreatic duct T.W. Sadler, Langman's medical embryology, 14th edition Development of the pancreas Bile duct Dorsal pancreatic bud Opening of bile and Accessory pancreas pancreatic ducts pancreatic duct E F G K. Moor, Before we are born, 10th edition Duodenum: - duodenal stenosis/atresia - results from incomplete recanalization; affects 20-30% of patients with Down syndrome, 20% of premature neonates symptoms: polyhydramnios „Doble-Bubble" = stomach and proximal duodenum K. Moor, Before we are born, 10th edition Liver - birth deffects are rare: Accessory hepatic ducts - usually asymptomatic, in 5% of population Gallbladder duplication - usually asymptomatic Intrahepatic biliary duct atresia/hypoplasia (1/100000) https://www.researchgate.net/publication/342134005_Prenatal_u ltrasound_ diagnosis_of_duplication_gallbladder_a_multicenter_study Extrahepatic biliary atresia (1/15000 in US, however, higher rates in East Asia) - 15-20% has a potent proximal duct and fixable defect, the rest requires the liver transplant; symptoms: neonatal jaundice; Kasai procedure (hepatoportoenterostomy) -> liver transplant!!! The dotted lines show areas that can be During the Kasai procedure, the intestine is affected by biliary atresia attached to the liver. This allows bile to drain. Colestase em Recem-Nascidos e Pequenos Lactentes I Concise Medical Knowledge Pancreas: Annular pancreas Accessory pancreatic tissue Accessory spleens - in 10 % of population A newborn patient with both annular pancreas and Meckel's di... : Medicine (lww.com) Midgut development. Physiological herniation. T.W. Sadler, Langman's medical embryology, 14th edition Midgut development. Physiological herniation. Body wall defects Gastroschisis (3,5/10000) - most common in infants from thin women under 20; usually not associated with chromosomal abnormalities and other severe defects, thus the mortality rate is low (unless associated with volvulus) ■ ■ j Omphalocele (2,5/10000) up to 25 % mortality rate https://www.researchgate.net/publication/270909178_Gastroschisis_Arteratal_Sonographic_Predictors_of_Adverse_Neonatal_Outcome Omphalocele I Childrer's Hospital of Philadelphia (chop.edul Vitelline duct abnormalities Meckel or ileal diverticulum - in 2 to 4 % of people, 3-5 times more prevalent in males Enterocystoma or vitelline cyst Umbilical or vitelline fistula Umbilicus--: Meckel diverticulum \ Ileum Vitelline cyst I B Vitelline fistula A newborn patient with both annular pancreas and Meckel's di... : Medicine (lww.com) Vitelline ligament Vitelline ligaments T.W. Sadler, Langman's medical embryology, 14th edition Gut rotation defects Left-sided colon - colon and cecum are the first to return from the umbilical cord cavity as the result of only 90° rotation Reversed rotation of the intestinal loop Duplications of intestinal loops and cysts Gut atresias and stenoses - Most occur in duodenum, fewest in the colon, equal number in jejunum and ileum; in 50 % of cases a region of bowel is missing completely, in 20 % cases the fibrous cord is present; stenoses represent only 5 % of cases Apple peel atresia -10 % of atresias: in the proximal jejunum, intestine is short, portion distal to the lesion coiled around remanant of mesenteries Hindgut Hindgut derivatives: - Left third of the transverse colon, descending colon, sigmoid colon, rectum, superior part of the anal canal - The epithelium of the urinary bladder and most of the urethra!!! Cloaca Phallus Hindcut Urorectal septum Anal p t Urorectal sapturn AJIantois Mesanchyrna Urorectal septum Hindgut Infolding of ^ cloaca! wall Level of section ß. Urogenital sinu Urorectal septum infolding o' lateral wall of cloaca Ftactum Level of section D, □1 Developing Uragenilal membránu ui nary bladder Urorectal septum Rectum Anal canal Anal pil Urogenital sinus Urorectal septum Perineum 'Rectum p Level of section F, K. Moor, Before we are born, 10th edition Anal membrane Congenital megacolon (Hirschsprung disease) - 1/5000, males are affected 4 times more often than females. Imperforate anus -1/5000 more common in males than females Anorectal birth defects - High vs. Low (rectum ends superior or inferior to the puborectalis muscle respectively) Low: anal agenesis, with or without fistula anal stenosis membranous atresia of anus High: anorectal agenesis, with or without fistula (2/3 of anorectal defects) rectal atresia Development of the face K. Moor, Before we are born, 9th edition Anterior cleft deformities Lateral cleft lip (1/700, 65 % male infants) Cleft upper jaw Cleft between the primary and the secondary palates Primary Incisive palate y~V foramen ■ Nostril Lip x- Uvula Posterior cleft deformities Cleft secondary palate (1/1500, 55 % female infants) Cleft uvula Philtrum of lip Primary palate T.W. Sadler, Langman's medical embryology, 14th edition Van der Woude syndrome - pits in the lower lip in 88 % of patients Van der Woude Syndrome (30.10.2020) (aerzteblatt.de) Oblique facial cleft Median cleft lip - incomplete merging of the two medial nasal prominences; different degrees of midline structures loss------- holoprosencephaly - fusion of lateral ventricles, synophtalmia (A) Preoperative feature of median cleft lip. (B) Out -ome of surgery at 9 mor ths pos (operativ ely. A natural Cupid's bow, phil rum and tubercle was achieved. 1 ® s ---- _® (A) Preoperativ achieved posto p and upper lip pit (B) Repaired median cleft lip with pit removal. Natural, symmetrical Cupid's bow was icision of the accompanying upper lip pit was done. https://www.researchgate.net/publication/303392213_Clinical_Features_and_Management_of_a_Median_Cleft_Lip Neck region T.W. Sadler, Langman's medical embryology, 14th edition Neck region - pharyngeal apparatus Ectoderm J Mesoderm Endoderm Pharyngeal Grooves Arches t I Cervical SiriuS Tongue buds Pharyngeal pouches 1st Thyroid diverticulum Foramen cecum Esophagus External acoustic meatus Cervical vesicle B Tu botym panic recess Palatine ton; inferior paratnyroid bud from 3rd pharyngeal pouch Superior parathyroid Ultimopharyngeal body bud from 4tn pharyngeal pouch K. Moor, Before we are born, 9th edition Tympanic cavity and pharyngotympanic tube Tongue Tympanic membrane Auricle Palatine tonsil Tonsillar sinus Former site of cervical sinus Foramen cecum External acoustic meatus Lymphoid tissue Skin of neck Superior parathyroid gland Inferior parathyroid gland Thyroid gland Ultimopharyngeal body Thymus K. Moor, Before we are born, 9th edition Craniofacial defects associated with neural crest cells Mandibulofacial dysostosis - Treacher Collins syndrome: autosomal dominant, 1/50000 Robin sequence: first-arch structures, 1/8500-micrognatia, cleft palate and glossoptosis 22qll.2 deletion syndromes: DiGeorge syndrome, DiGeorge anomaly, velocardiofacial syndrome etc. -1/4000 Hemifacial microsomia (oculoauriculovertebral spectrum - Goldenhar syndrome) - 1/5600, assymetry in 65% cases; involves maxillary, temporal, zygomatic bones, ears, eyes, vertebrae. Cardiac deffects in 50% cases. https://economictimesjndiatimesxom/magazines/panache/m was-rejected-by-biological-parents-36-hrs-after-birth-for-his-face-but-his-adoptive-mom-did care/articleshow/93541374.cms?from=mdr Case 1 - One Stage Microtia Reconstruction for Hemifacial Microsomia - Before and After Gallery