Development and teratology of digestive system. Development of facial and cervical region, face clefts. Anna Mac Gillavry 13.03.2023 • Primitive gut formation results from the lateral folding of the embrio • 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 4 weeks Foregut Tracheoesophageal septum Respiratory diverticulum — Pharynx - Trachea Lung buds c i I Esophagus T.W. Sadler, Langman's medical embryology, 14th edition Stomach curvature https://www.drawittoknowitxom/course/em Dorsal mesogastrium 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-Pyr end part of esophagus -Tracheoesophageal fistula Distal part of esophagus B Communication of esophagus i with trachea Stomach: - pyloric stenosis (1 in 150 males, 1 in 750 females) - developes 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 Major papilla' pancreatic duct Ventral pancreatic duct A B 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 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!!! Intrahepatic biliary duct atresia/hypoplasia (1/100000) Pancreas: Annular pankreas 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. Gastroschisis (3,5/10000) - most common in infants from thin women under 20; usually not associated with chromosomal abnormalities and other severe deffects, thus the mortality rate is low (unless associated with volvulus) Body wall defects Omphalocele (2,5/10000) -up to 25 % mortality rate https://wwwTesearchgate.net/publication/27090 Omphalocele I Children's Hospital of Philadelphia (chop.edu) Vitelline duct abnormalities Meckel or ileal diverticulum - in 2 to 4 % of people, 3-5 times more prevalent in males (inflamation symptoms mimic those of appendicites) Enterocystoma or vitelline cyst Umbilical or vitelline fistula Vitelline cyst Umbilicus Meckel diverticulum Ileum 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 L Urorectal saplurn AJIantois Mesanchyrna Urorectal septum Hindgut Infolding of ^ cloaca! wall Level of section ß. Urogenital sinu: Uroredal septum Kuntu 11 infolding o' lateral wall of cloaca 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 puborectolis 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 Transition Zone in Hirschsprung's Disease I NEJM 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*r~Nlv foramen Nostril Lip X- Uvula Posterior cleft deformities Cleft secondary palate (1/1500, 55 % female infants) Cleft uvula Philtrum of lip Primary ^pa,a,e 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 and upper lip pit (B) Repaired median cleft lip with pit removal. Natural, symmetrical Cupid's bow was achieved postoperatively and successful excision of the accompanying upper lip pit was done. https://wwwTesearchgate.net/publication/303392213_Clinical_Features_and_Ma 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 SinuS 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 ot cervical sinus Foramen cecum External acoustic meatus Lymphoid tissue Skin of neck Superior parathyroid gland Inferior parathyroid gland Thyroid gland Ultimopharyngeal body N Thymus K. Moor, Before we are born, 9th edition Ectopic thymic and parathyroid tissue Branchial fistulas: external and internal Cervical cysts Craniofacial defects associated with neural crest cells: - Mandibulofacial dysostosis-Treacher Collins syndrome - Robin sequence - DiGeorge syndrome, DiGeorge anomaly, velocardiofacial syndrome etc. - deletion on 22qll.2 (1/4000) - Hemifacial microsomia (oculoauriculovertebral spectrum - Goldenhar syndrome)