Anterior Abdominal Wall Defects

 Introduction: 


Most common congenital Anterior abdominal wall defects are Omphalocele & Gastroschisis.Combined incidence is 1:2000.It occurs equally in males & females.
 
 Etiology:
Omphalocele: Failure of lateral & caudal folds to unite (which forms anterior abdominal wall) causes intestines to remain outside the body wall.
Gastroschisis: Abnormal involution of right umbilical vein resulting in the mesenchymal defects at the junction of the body stalk & body wall.
Pathology:
Omphalocele: There is anterior midline defect at the base of the umbilicus through which abdominal viscera herniates into an avascular hernial sac composed of peritoneum, wharton's jelly & amnion.

Presence or absence of liver in the sac differentiates between large & small omphalocele respectively.
Gastroschisis: There is a defect in the abdominal wall either on right (commonest) or left side of umbilicus without membranous sac.
Diagnosis:
Antenatal: Ultrasonography
Maternal serum AFP
Acetyl Cholinesterase
Amniocentesis & Chromosomal analysis
Postnatal: Clinical & Ultrasonography
Associated Syndromes:
1) Cantrell Pentalogy: Epigastric omphalocele, Anterior diaphragmatic hernia, Sternal cleft,
Ectopia cordis, Cardiac anomaly.

2) Beckwith Wiedemann syndrome: Exomphalos, macroglossia, gigantism

3) Trisomy syndrome

4) Prune belly Syndrome
Associated Conditions:
Intestinal malrotation, Meckel's diverticulum, Treacheo-esophageal Fistula, Undescended testis,
Small bowel atresia.
Management: Conservative (omphalocele):

1) Topical application of escharotic agents
2) Delayed external compressive reduction of omphalocele
Surgical management:
1) Primary closure of anterior abdominal wall defect
2) Staged silo closure
3) Skin flap closure( ventral hernia)
4) Repair using synthetic grafts