Abnormal Fetal GI Tract PDF

ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 55 56 Jejunal atresia Ileal atresia • Transverse abdomen • Coronal abdomen • Multiple large, tubular cystic areas • 32 weeks GA • Confirmed at surgery Arrow: normal intestinal fold 57...

ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 55 56 Jejunal atresia Ileal atresia • Transverse abdomen • Coronal abdomen • Multiple large, tubular cystic areas • 32 weeks GA • Confirmed at surgery Arrow: normal intestinal fold 57 UB: bladder 58 Small Bowel Obstruction Volvulus (twisted bowel) Volvulus (twisted bowel) • Transverse abdomen • 34 weeks GA • Grossly dilated, fluid filled loops of bowel • Dilated bowel loop with whirlpool sign plane Volvulus 59 Ultrasonography in Obstetrics and Gynecology, 5th Edition (Callen fig 15‐54) 60 Duodenal Atresia Duodenal Atresia • The highest small bowel atresia resulting in obstruction • Most common site of intestinal atresia • Co‐existing anomalies present 50% of the time • Association with trisomy 21 Uncommon 10 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 61 62 Duodenal atresia – sonographic features • “Double bubble” sign • Dilated stomach and first part of duodenum • Usually not seen before 24 weeks • ± Polyhydramnios (most cases) double bubble duodenal atresia Connection seen between stomach and duodenum confirms diagnosis 63 64 Duodenal atresia – double bubble Double bubble & polyhydramnios Duodenal atresia – double bubble Connection confirms diagnosis Ultrasonography in Obstetrics and Gynecology, 5th Edition (Callen fig 15‐17) 65 66 Meconium Ileus Meconium Ileus • Distal ileum obstructed with meconium • Meconium is thick, viscous, and inspissated • Occurs with cystic fibrosis Inspissate Thicken or congeal 11 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 67 68 69 70 Meconium ileus • Transverse mid‐abdomen • Dilated, echo‐filled loops of bowel • Mild polyhydramnios was present Meconium ileus – sonographic features • Dilated, echogenic, fluid‐filled loops of bowel • ± Polyhydramnios Meconium ileus – cystic fibrosis B: bowel Sp: spine 71 72 Meconium Peritonitis • Meconium Peritonitis Reactive, sterile chemical peritonitis secondary to small bowel perforation Peritonitis Inflammation of the peritoneum 12 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 73 74 Meconium peritonitis – sonographic features • Intraperitoneal calcifications • Ascites • Usually echogenic • ± Polyhydramnios Calcifications seen in two separate fetuses 75 76 Meconium peritonitis 18 weeks 26 weeks Meconium peritonitis • Transverse bowel • Echogenic bowel with ascites Perforated bowel in a fetus with cystic fibrosis Diagnostic Ultrasound, 5th Edition (Rumack fig 41.15) 77 30 weeks 78 Meconium peritonitis • Intra‐abdominal echogenic areas • Dilated bowel loops • Ascites dilated bowel loops Anorectal Atresia echogenic areas 13 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 79 80 Anorectal Atresia • Anorectal atresia • May be isolated Most common association • VACTERL syndrome • Vertebral anomalies • Anal atresia • Cardiac anomalies • TracheoEsophageal abnormalities • Renal/urinary anomalies • Limb defect Termination (closure) of the anal canal 81 82 VACTERL syndrome • Diagnosed when 3 or more of the listed anomalies are present • Most frequent defects: • Tracheoesophageal fistula • Anal atresia • Vertebral anomalies • NB: evaluate for all anomalies 83 Anorectal atresia – sonographic features • Dilated rectosigmoid colon • Tubular cystic structure in posterior pelvis • VACTERL anomalies 84 Anorectal atresia VACTERL syndrome • 35 weeks GA • Coronal abdomen and pelvis white arrows: dilated, fluid‐filled rectum & colon black arrow: enterolithiasis (intestinal calculus) Ultrasonography in Obstetrics and Gynecology, 5th Edition (Callen fig 15‐50) C: Dilated sigmoid colon & rectum • Oligohydramnios 2° to severe renal dysplasia 14 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 85 86 GI Tract Atresias Other GI Tract Atresias 87 • Can form anywhere between esophagus and anus • Single or multiple sites • Co‐existing anomalies common • May result in perforation • The higher the atresia the greater the risk of polyhydramnios altered swallowing • Uncommon diagnosis before 3rd trimester 88 SGI tract atresias – sites & sonographic features Esophageal Atresia 89 90 Esophageal Atresia • Rarely isolated Esophageal atresia Associated findings • Tracheoesophageal fistula • VACTERL association • Congenital anomalies Most common A: most common B: isolated EA ~50% of TE fistulas Ultrasonography in Obstetrics and Gynecology 5th Edition (Callen fig 15‐4) 15 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 91 92 Isolated esophageal atresia • Sonographic features: • Stomach cannot be visualized • Polyhydramnios • Blind ended, fluid filled pouch • Seen in neck • Most reliable sign • Often not seen until 28 weeks GA Isolated esophageal atresia • Absent fetal stomach at level of the AC • Polyhydramnios Textbook of Diagnostic Sonography 7th Edition (Hagen‐ Ansert fig 62‐11) 93 94 Isolated EA Esophageal atresia • Pouch sign in neck • Coronal neck • Most reliable sonographic sign of EA (seen with or without TE fistula) • Pouch sign (arrow) • After a short time period the pouch disappeared P: pouch HP: pharynx 95 Ultrasonography in Obstetrics and Gynecology, 5th Edition (Callen fig 15‐4) 96 EA – amniotic fluid Esophageal atresia with tracheoesophageal fistula Sonographic features: • This quadrant was 10 cm AP • No stomach bubble seen • Stomach usually seen • Diagnosed with EA • Polyhydramnios in 1/3 • Polyhydramnios is more common the higher the GI tract atresia • Pouch sign • Stomach seen? Textbook of Diagnostic Sonography, 7th Edition (Hagen‐Ansert fig 62‐12) 16 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 97 98 Echogenic Bowel Definition • Echogenic Bowel 99 Bowel isoechoic to fetal bone 100 Echogenic bowel – causes • High frequency transducer (can be normal) • 3rd trimester (can be a normal finding) Abnormal chromosomes • e.g. trisomy 21 • Echogenic bowel – outcomes • Intra‐amniotic bleeding • Normal variant (50%) • Abnormal bowel • Premature birth • Cystic fibrosis • Fetal demise • CMV (TORCH) • IUGR 101 102 Effect of probe frequency If bowel appears hyperechoic at high frequency you must confirm at low frequency EVS – echogenic bowel 5 MHz 8 MHz JUM\Dec 99\fig 1a&b pg 800 TAS Ultrasonography in Obstetrics and Gynecology, 5th Edition (Callen fig 15‐53) 17 ULTR‐3014 OBGYN Sonography 3 Module O.12: Abnormal Fetal Heart & Abdomen 4 Abnormal Fetal GI Tract 103 104 Echogenic bowel – meconium • Coronal abdomen • 34 weeks GA • Meconium in colon • Almost always a normal finding in the 3rd trimester 105 Echogenic bowel – chromosomal associations • EB associated with aneuploidy Most common • Trisomy 21 • Trisomy 13 • Trisomy 18 • Sex chromosome abnormalities Aneuploidy Presence of an abnormal number of chromosomes 106 Echogenic bowel – trisomy 21 • Bowel with same echogenicity as fetal bone Echogenic bowel – non‐chromosomal associations • Congenital bowel malformations • Intra‐amniotic bleeding • Cystic fibrosis • Congenital infections • IUGR Textbook of Diagnostic Sonography, 7th Edition (Hagen‐Ansert fig 53‐16) 107 Module O.12 Abnormal Fetal Heart & Abdomen Abnormal GI Tract Continued in Abnormal Abdominal Wall 18