ABSTRACT
OBJECTIVES: To evaluate conservative management of fetal and neonatal ovarian cysts. METHODS: We followed the progress of 11 fetal and 2 neonatal ovarian cysts. RESULTS: Ten fetal cysts were simple at recognition, but 8 silently became complex by birth, with ovarian loss in 6/11 cases (54%). In 2 cases where large simple cysts presented for the first time at birth, serious complications occurred, resulting in the death of 1 newborn. CONCLUSIONS: If a fetal ovarian cyst is already complex before birth it can be managed conservatively, albeit with loss of the ipsilateral ovary in the majority of cases. As simple fetal ovarian cysts frequently become complex before birth, intervention may be justifiable to preserve the ovary. But any intervention also has the potential for complications, and may be ineffective. Intervention also requires accurate differentiation of ovarian cysts from other abdominal cysts.
Subject(s)
Fetal Diseases/therapy , Infant, Newborn, Diseases/therapy , Ovarian Cysts/therapy , Female , Fetal Diseases/diagnostic imaging , Follow-Up Studies , Humans , Infant, Newborn , Infant, Newborn, Diseases/mortality , Ovarian Cysts/congenital , Ovarian Cysts/diagnostic imaging , Pregnancy , Retrospective Studies , Severity of Illness Index , Ultrasonography, PrenatalABSTRACT
The authors report a gastric duplication cyst detected antenatally and its subsequent laparoscopic removal at 2 months of age. Before birth, a cystic mass was detected behind the stomach on fetal ultrasound scan (US). After birth, an US, barium meal, nuclide scan, and cervical and thoracic vertebral x-rays suggested that the most probably diagnosis was a gastric duplication cyst. At 2 months of age, laparoscopic removal of the cyst was performed with closure of the muscle defect in the stomach wall. The patient was discharged 4 days later, feeding normally. Histology findings confirmed the diagnosis of a gastric duplication cyst. After the antenatal detection of a cyst behind the stomach, the laparoscopic removal of this gastric duplication in a 2 month old was accomplished without complications. This appears to be the first reported case using this type of procedure in an infant.
Subject(s)
Brain Diseases/diagnostic imaging , Brain Diseases/surgery , Cysts/diagnostic imaging , Cysts/surgery , Fetal Diseases/diagnostic imaging , Thoracic Diseases/diagnostic imaging , Thoracic Diseases/surgery , Brain Diseases/congenital , Brain Diseases/embryology , Choroid Plexus/embryology , Cysts/congenital , Cysts/embryology , Female , Humans , Infant, Newborn , Laparoscopy/methods , Stomach/abnormalities , Thoracic Diseases/congenital , Thoracic Diseases/embryology , Ultrasonography, PrenatalABSTRACT
PURPOSE: The aim of this study was to evaluate delayed elective resection of antenatally detected enteric duplication cysts. METHODS: A retrospective casenote study of intraabdominal cysts detected antenatally between January 1991 and January 2002 found 37 fetuses with cysts. Twelve were enteric duplications. Two were duodenal, 1 was an 85-cm tubular jejunoileal duplication, and 9 were ileocecal. Asymptomatic cysts were followed with serial ultrasound scars and resected electively over 14 months. RESULTS: Three neonates had small bowel obstruction demanding laparotomy: 1 of the 2 infants with duodenal duplication cysts, 1 infant with an ileocecal duplication, and the infant with the tubular duplication. One with an ileocecal duplication became symptomatic at 2 months and underwent a laparotomy. Seven had their duplications resected electively between 6 weeks and 14 months, and the other is still being followed. Four of the 7 asymptomatic duplications electively resected contained gastric mucosa. CONCLUSIONS: Intraabdominal enteric duplication cysts are increasingly likely to be detected antenatally. The majority are likely to remain asymptomatic for several months at least, after which a resection can be planned. The prevalence of gastric mucosa suggests that they should not be left indefinitely. Laparoscopically assisted resection of ileocecal duplications is safe and effective.
Subject(s)
Cysts/diagnostic imaging , Duodenum/abnormalities , Ileum/abnormalities , Ultrasonography, Prenatal , Cysts/surgery , Digestive System Abnormalities/diagnostic imaging , Digestive System Abnormalities/surgery , Duodenum/diagnostic imaging , Female , Fetal Diseases/diagnostic imaging , Humans , Ileum/diagnostic imaging , Infant , Infant, Newborn , Pregnancy , Retrospective StudiesABSTRACT
Type I choledochal cyst is a rare saccular or fusiform congenital dilatation of the extrahepatic biliary tract. It is usually treated by laparotomy at which the cyst is completely excised and a Roux-en-Y hepaticojejunostomy is performed to establish biliary enteric drainage. We report the laparoscopic excision and hepaticoduodenostomy of type I choledochal cyst in two girls aged 1 and 3 years. The entire procedure was performed laparoscopically using needlescopic instruments. A 7-mm telescope port was inserted at the umbilicus, a 3-mm port in the right upper quadrant, and a 6-mm port in left upper quadrant. An additional 3-mm fan-shaped liver retractor was passed through the abdominal wall without a trocar. The gallbladder and choledochal cyst was dissected and removed en bloc. The lower end of the common bile duct was closed with 5-0 polydioxanone. The duodenum was anastomosed to the common hepatic duct below the confluence of the right and left hepatic ducts. There were no intraoperative complications, and the children were asymptomatic with no episodes of cholangitis at 6 months follow-up. Pediatric surgeons trained in advanced laparoscopic techniques including intracorporeal suturing can perform laparoscopic repair of choledochal cyst safely.
Subject(s)
Anastomosis, Surgical/methods , Choledochal Cyst/surgery , Laparoscopy , Child, Preschool , Cholecystectomy, Laparoscopic/methods , Common Bile Duct/surgery , Duodenostomy/methods , Feasibility Studies , Female , Gallbladder/surgery , Hepatic Duct, Common/surgery , Humans , Infant , Liver/surgery , Safety , Treatment OutcomeABSTRACT
Congenital diaphragmatic hernia (CDH) is a common abnormality affecting 1 in 2,000 gestations. The mortality exceeds 50% despite recent advances in postnatal treatment. The widespread antenatal use of glucocorticoids to induce lung maturation in fetuses at risk of premature delivery suggests a potential for a therapeutic effect in other fetuses with impaired lung development. The parents of three fetuses referred with CDH and features suggesting a poor postnatal prognosis (early diagnosis, liver herniation, and lung area-to-head circumference ratio <1.0, or associated abnormalities) elected to receive maternal betamethasone starting at 24 to 26 weeks' gestation rather than undergo a fetal tracheal plug. All three infants survived and were extubated within 10 days. The long-term use of antenatal steroids in the treatment of CDH may thus be of benefit and warrants further study.
Subject(s)
Anti-Inflammatory Agents/therapeutic use , Betamethasone/therapeutic use , Fetal Diseases/drug therapy , Hernia, Diaphragmatic/drug therapy , Hernias, Diaphragmatic, Congenital , Lung/drug effects , Lung/pathology , Female , Humans , Infant, Newborn , Male , Pregnancy , Prognosis , Treatment OutcomeABSTRACT
Cystic dysplasia of the rete testis (the network of straight seminiferous tubules within the mediastinum testis leading to the efferent ductules) is a rare congenital anomaly. There are only 15 cases reported in the literature to date and only one report of the US findings [1-5]. This report highlights the characteristic appearance of the lesion on ultrasound examination and its association with renal abnormalities in two patients.
Subject(s)
Abnormalities, Multiple/diagnostic imaging , Cysts/diagnostic imaging , Kidney/abnormalities , Kidney/diagnostic imaging , Rete Testis/abnormalities , Rete Testis/diagnostic imaging , Child , Cysts/congenital , Humans , Infant , Male , Recurrence , Rete Testis/pathology , UltrasonographyABSTRACT
The incidence of congenital diaphragmatic hernia (CDH) is 1:1,200-5, 000, and the condition is associated with high mortality and morbidity attributed principally to associated pulmonary hypoplasia. One treatment approach has been for intrauterine intervention to induce lung growth to a sufficient level to allow survival at birth. Repair of the hernia in utero has been attempted, using a method of immediate reduction and repair of the hernia (patch) compared to a slow reduction method using a silastic "silo" sewn over the diaphragm defect to contain the hernial contents. In animal studies, this second method has been associated with lower fetal morbidity and mortality. This study, utilizing the sheep model of CDH, focuses on analysis of lung structural development and maturation, comparing the efficacy of the immediate vs. slow methods of hernial repair in preventing/reversing pulmonary hypoplasia. We hypothesized that: a) Both the immediate (patch) and slow (silo) methods of hernia repair performed in the lamb model of CDH will stimulate lung growth and structural development and restore lung structure and maturity towards normal levels by term gestation; b) Effects will be detectable by morphometric measurement of the following parameters: lung volume; parenchyma to nonparenchyma tissue ratio; volume density of connective tissue in nonparenchyma; gas exchange tissue to airspace ratio; gas exchange surface area; capillary loading; alveolar/airspace density; and alveolar perimeter; c) Effects will be seen in all lobes of the lung; and d) There will be no significant difference in lung size or structural parameters between the two groups. Forty-four pregnant ewes were allocated randomly to one of four groups. Fetal lambs in three groups (n = 36) underwent CDH creation at days 72-74 of gestation. Of surviving lambs showing an adequate hernia, 9 were not operated on further, 11 underwent "repair" using a silastic chimney around the hernial contents (slow reduction), and 11 underwent "repair" by a silastic patch over the diaphragmatic defect (immediate reduction). The fourth group were normal controls. All surviving lambs (n = 8 in each group) were delivered by Cesarian section at 141-143 days (term = 145-149 days). Lungs were obtained at autopsy, inflation-fixed, divided into lobes, and sampled, and morphometric analysis was performed. Comparisons were made between these groups and with matched normal controls and CDH untreated animals prepared in conjunction and previously reported. The lungs from the CDH animals treated by both methods of fetal hernia repair showed significant lung growth and structural development and maturation, although they remained significantly hypoplastic compared to normal. There were minor differences in the lung parameters between these two groups, with a tendency for the slow method to provide more normal parameter values. An exception was the increase in lung volume that was greater for the immediate (patch) method, particularly in the left lower lobe. In conclusion, intrauterine hernia repair by both methods is capable of partially reversing total lung and lobar structural hypoplasia and immaturity. The slow reduction method, with reduced potential for mortality and morbidity, is at least as good at reversing pulmonary hypoplasia as the immediate method. Alternative intrauterine interventions to prevent or reverse pulmonary hypoplasia are discussed and compared with the hernia repair methods used in this study.
Subject(s)
Hernia, Diaphragmatic/surgery , Hernias, Diaphragmatic, Congenital , Lung Diseases/etiology , Lung/embryology , Animals , Biometry , Disease Models, Animal , Female , Lung/pathology , Pregnancy , Prenatal Diagnosis , Random Allocation , Sheep , Surgical MeshABSTRACT
Twenty-nine patients with congenital duodenal obstruction (DO) detected as a "double bubble" (DB) on antenatal ultrasound (US) or diagnosed postnatally were seen at the Women's and Children's Hospital between 1985 and 1994; 24 (83%) had antenatal scans, with 21 (87%) DBs visualised. The 3 fetuses with normal scans who developed DO postnatally had duodenal "windsocks". Five of the 24 scanned patients (21%) were found to have a DB before 20 weeks' gestation: 1 simple duodenal atresia, 2 duodenal atresias with chromosomal abnormalities (1 trisomy 21 and 1 triploidy), 1 biliary atresia with a pre-pyloric vein, and 1 malrotation. Sixteen (67%) cases were detected with scans after 20 weeks (range 28-36 weeks); 12 (75%) of these were done for polyhydramnios. In response to a questionnaire to 9 of the 16 parents whose fetuses underwent a late scan, 5 had had normal early scans elsewhere and 4 did not respond (4 of the remaining 7 had died and 3 were lost to follow-up). Eleven of the 29 patients (38%) had abnormal karyotypes, and 4 (22%) of the 18 with a normal karyotype had associated anomalies. Two sets of familial cases were noted. Early antenatal diagnosis of DO is possible in a minority of cases, and this early diagnosis may be associated with an increased risk of other pathology. Furthermore, early demonstration of a DB at routine US prior to 20 weeks allows appropriate counseling and the option of mid-trimester termination, whereas this is more difficult later in the pregnancy. In all cases detected antenatally, planning of delivery and parent counseling should be achieved.
Subject(s)
Abnormalities, Multiple/diagnostic imaging , Duodenal Obstruction/congenital , Duodenal Obstruction/diagnostic imaging , Ultrasonography, Prenatal/methods , Abnormalities, Multiple/genetics , Duodenal Obstruction/complications , Duodenal Obstruction/genetics , Female , Genetic Counseling , Humans , Infant, Newborn , Karyotyping , Male , Pregnancy , Pregnancy Trimester, Second , Retrospective Studies , Surveys and QuestionnairesABSTRACT
A patient aged 16 years was referred following numerous episodes of intense pruritus associated with persistently altered liver function tests. Ultrasound (US) demonstrated the superior mesenteric vein positioned more to the left than usual and abnormal orientation of the duodenum, consistent with a midgut malrotation. Endoscopic retrograde cholangiopancreatography the common bile duct, suggesting a malrotation with chronic or recurrent volvulus. A classic malrotation with 180 degrees volvulus was noted at operation. A second child previously thought to have recurrent idiopathic pancreatitis was noted to have ampullary distortion secondary to malrotation following presentation with an intestinal obstruction. Pruritus and pancreatitis have not been previously reported with malrotation, although cholestatic jaundice has been described. The diffculties in diagnosis and the role of US are discussed. Ladd's procedure is the appropriate treatment for this condition.
Subject(s)
Cholestasis/pathology , Intestinal Obstruction/pathology , Intestines/abnormalities , Pancreatitis/pathology , Pruritus/pathology , Adolescent , Female , HumansABSTRACT
Congenital diaphragmatic hernia (CDH) in humans carries high mortality/morbidity attributed to associated pulmonary hypoplasia. An understanding of the effects of CDH on fetal lung growth is important for development of successful treatments. This study aimed to quantitate structural differences between normal and CDH-affected preterm lamb lungs. We hypothesized that (a) pulmonary hypoplasia is present in preterm CDH-affected lungs; (b) the relative degree of pulmonary hypoplasia increases with gestation; and (c) the left upper lobe (LUL) is affected most. Fetal lambs were allocated to two groups. One group underwent surgery (72-74 days gestation) inducing CDH. Both groups (n = 7, n = 7) were delivered by cesarean section at 129 days (term: 145-149). Lungs were obtained at autopsy, were inflation-fixed, processed for histology, and morphometry was performed. Preterm lungs of CDH-affected lambs in comparison to those of normal lambs demonstrated a reduction in the following: lung weight (37.7 g vs. 116.3 g); lung weight:body weight (0.012 vs. 0.040); fixed lung volume (33.6 ml vs. 96.9 ml); gas-exchange surface area (4.56 m(2) vs. 13.70 m(2)); parenchyma:nonparenchyma (59:41 vs. 72:28); and parenchymal airspace:tissue (16:84 vs. 35:65). Non-parenchyma connective tissue was increased (58%), airspaces were more numerous (1077/mm(2)) and smaller (perimeter 76.6 microm), gas-exchange surface density (2394 cm(-1)) was greater and capillary loading (0.04 ml/m(2)) was reduced compared to preterm normal lung (49%; 778/mm(2); 108.7 microm; 2003 cm(-1), 0.11 ml/m(2), respectively). The LUL was affected most. These data quantitate pulmonary hypoplasia in preterm CDH-affected lambs. Comparisons with published data indicate increasing relative hypoplasia as gestation proceeds. Fetal interventions will affect lung development, depending on timing, with intervention still likely to be worthwhile during late gestation.
Subject(s)
Hernias, Diaphragmatic, Congenital , Lung/embryology , Sheep Diseases/pathology , Animals , Disease Models, Animal , Female , Pregnancy , Respiratory Function Tests , SheepABSTRACT
Twenty-one extremely-low-birth-weight (ELBW) and premature infants (<29 weeks' gestation and/or <1,000 g) underwent emergency laparotomy for acute intra-abdominal pathology (necrotising enterocolitis [NEC] 16, other bowel pathology 5) during the 4-year period from 1990 to 1993; 11 died. The neurodevelopmental outcome of the 10 survivors was assessed and compared with 20 living, otherwise normal controls matched for gestational age, birth weight, and year of birth to asses the effect of the abdominal event on quality of survival. Those who survived after laparotomy had a worse neurodevelopmental outcome than controls (P < 0.05). During this period, we also compared 24 infants in the ELBW category who developed NEC but did not require a laparotomy with the 16 ELBW infants with NEC who required a laparotomy. Those who required a laparotomy had worse disease and had significantly worse neurodevelopmental outcomes (P < 0.01). ELBW and premature infants who have acute intra-abdominal pathology requiring a laparotomy are thus at increased risk of neurodevelopmental problems and poor growth. Close long-term follow-up is important, and the families of such infants should be made aware before surgery of the increased risk the abdominal event has on their babies' developmental outcome if they survive.
Subject(s)
Developmental Disabilities , Enterocolitis, Necrotizing/surgery , Infant, Low Birth Weight , Intestinal Diseases/surgery , Growth , Humans , Infant, Newborn , Intelligence , LaparotomyABSTRACT
OBJECTIVE: To determine the influence of antenatal ultrasound on the management of exomphalos. METHODS: Retrospective case note review of 23 fetuses and infants referred to our institution with either a pre- or postnatal diagnosis of exomphalos over a 7-year period. RESULTS: There were 21 cases of exomphalos of which 18 were correctly diagnosed on antenatal ultrasound by 18 weeks' gestation. There were 2 false-positives and 3 false-negatives, including 1 case of amniotic band syndrome with an abdominal wall defect and 1 morphologically normal fetus. Associated anomalies were correctly identified in 12 but incorrectly reported in 8. Maternal serum alpha-fetoprotein levels were abnormal in 61% of cases of abdominal wall defects in this series. Amniocentesis was performed in 12 and cordocentesis in 1. There were 13 terminations, including 2 trisomy 18s and 1 trisomy 13. Two fetal deaths followed amniocentesis. Of the 10 live births, 9 had their exomphalos repaired with a 1-year survival rate of 89%. Prenatal diagnosis did not appear to influence outcome. CONCLUSIONS: Antenatal ultrasound diagnosed 86% of cases of exomphalos and correctly reported 67% of associated anomalies. Amniocentesis may have led to the death of 1 morphologically normal fetus.
Subject(s)
Hernia, Umbilical/diagnostic imaging , Hernia, Umbilical/therapy , Ultrasonography, Prenatal , Abortion, Eugenic , Adolescent , Adult , Amniocentesis/adverse effects , Diagnostic Errors , Female , Hernia, Umbilical/surgery , Humans , Infant, Newborn , Pregnancy , Prognosis , Retrospective Studies , alpha-Fetoproteins/analysisABSTRACT
BACKGROUND: Surgical central venous access in children usually requires open exposure of the internal jugular vein or one of its tributaries. The percutaneous route has the potential advantages of a reduced rate of wound infection, superior cosmesis and reduced operating time. We report our modifications to the percutaneous approach that facilitate the application of this technique to children over the age of 12 months. METHODS: The dilator and peel-away sheath of the introducer set should be inserted into the subclavian vein under fluoroscopic control. Elevation of the ipsilateral shoulder assists passage of the peel-away sheath and subsequently the catheter from the subclavian vein into the superior vena cava. RESULTS: This technique has been used successfully to establish surgical central venous access in the majority of children at the Women's and Children's Hospital, Adelaide, South Australia, over a 3-year period. CONCLUSIONS: With the modifications described this technique may be safely applied to the paediatric age group.
Subject(s)
Catheterization, Central Venous/instrumentation , Catheterization, Central Venous/methods , Anesthesia, General , Catheterization , Catheterization, Central Venous/standards , Child , Child, Preschool , Humans , Infant , Subclavian Vein , Vena Cava, SuperiorABSTRACT
Perioperative heat loss is a potentially serious complication of surgery in infants. The influence of laparoscopic surgery on perioperative hypothermia has not previously been documented. We reviewed heat loss in 26 infants undergoing laparoscopic pyloromyotomies compared with 42 control patients having the standard open procedure over the same time period. The mean fall in temperature in the laparoscopic group was -0.69 degreesC compared with -0.47 degreesC in the open group. This difference was not significant, with a P value of 0.077. This may reflect the small sample size and the relatively short duration of this procedure with few instrument changes. There was a trend for increased heat loss in the laparoscopic group, which might have implications for longer and more complex laparoscopic procedures in infants.
Subject(s)
Body Temperature Regulation , Hypothermia/etiology , Laparoscopy/adverse effects , Humans , Infant , Pyloric Stenosis/surgery , Retrospective StudiesABSTRACT
Two boys developed bile-stained vomiting shortly after being involved in significant right-sided blunt trauma and sustaining fractured right femurs. Both had intestinal volvulus and both had a history of bile-stained vomiting in infancy, which had been investigated and interpreted as normal.
Subject(s)
Accidental Falls , Accidents, Traffic , Femoral Fractures/complications , Intestinal Obstruction/complications , Intestine, Small/injuries , Wounds, Nonpenetrating/complications , Abdominal Pain/etiology , Child, Preschool , Femoral Fractures/diagnostic imaging , Follow-Up Studies , Humans , Intestinal Obstruction/diagnostic imaging , Intestinal Obstruction/surgery , Intestine, Small/diagnostic imaging , Intestine, Small/surgery , Laparotomy , Male , Radiography , Vomiting/etiology , Wounds, Nonpenetrating/diagnostic imagingABSTRACT
Recurrent tracheoesophageal fistula may complicate primary repair of congenital tracheoesophageal fistula. Standard treatment involves repair via a right lateral thoracotomy and use of adjacent soft tissues to separate the suture lines of the fistulous openings. The authors describe an alternative approach via a median sternotomy, which improves access, reduces the operating time required to identify the recurrent fistula, and enables the use of a pedicled sternocleidomastoid muscle flap to decrease the risk of refistulization.
Subject(s)
Sternum/surgery , Surgical Flaps , Tracheoesophageal Fistula/surgery , Female , Humans , Infant , Infant, Newborn , Recurrence , Tracheoesophageal Fistula/congenitalABSTRACT
A routine ultrasound scan in a primigravida at 29 weeks' gestation showed that her fetus had a fluid-filled viscus above the diaphragm in the mid-line. This was initially thought to be the stomach, either as part of a congenital Bochdalek diaphragmatic hernia or an hiatus hernia. Subsequent scans suggested that this was the stomach with an additional loop of bowel. After birth, laparotomy confirmed that the stomach had herniated into the chest through a very lax oesophageal hiatus. The stomach was easily reduced into the abdomen with no evidence to suggest a congenital short oesophagus, the crura were tightened, and an anterior fundoplication performed.
Subject(s)
Fetal Diseases/diagnosis , Hernia, Hiatal/diagnosis , Adult , Female , Fetal Diseases/diagnostic imaging , Fundoplication , Hernia, Hiatal/diagnostic imaging , Hernia, Hiatal/surgery , Humans , Infant, Newborn , Pregnancy , Radiography , Ultrasonography, PrenatalABSTRACT
The incidence of congenital diaphragmatic hernia (CDH) is 1:1,207-5,000, and the condition is associated with high mortality and morbidity, attributed principally to associated pulmonary hypoplasia. Repairing the diaphragmatic defect by antenatal surgery has high mortality, mainly due to premature labor. Antenatal tracheal occlusion, which is achievable by less invasive methods, stimulates lung growth (weight and DNA). However, its effectiveness in reversing structural and maturational abnormalities and its optimal timing requires further investigation. We hypothesized that (1) antenatal tracheal occlusion performed in the lamb model of congenital diaphragmatic hernia will stimulate lung growth and structural development and restore lung structure and maturity toward normal levels by term gestation; (2) effects will be detectable by morphometric measurements of the following parameters: lung volume, ratio of parenchyma to nonparenchyma, volume density of connective tissue within nonparenchyma, ratio of gas exchange tissue to airspace in parenchyma, gas exchange surface area, capillary loading, alveolar/airspace density and alveolar perimeter; (3) effects will be seen in all lobes of the lung; and (4) a greater effect will be observed when tracheal occlusion is performed early rather than late in gestation. Fourteen lambs underwent CDH creation at gestation day 72-74 followed by tracheal occlusion at day 101 (n = 7) or 129 (n = 7). They were delivered by Cesarean section at 143 days (term = 145-149). Lungs were obtained at autopsy, inflation fixed, divided into lobes, and sampled; morphometric analysis was performed. Comparisons were made with previously reported results from control lungs of normal lambs and lambs with untreated CDH. In comparison with untreated lungs, antenatal tracheal occlusion at both times resulted in increased volumes for total lung and lobes, increased volume density of parenchyma and of airspace within parenchyma, and increased gas exchange surface areas. Normal values for gas exchange surface area density, and alveolar density and perimeter were attained and the lungs appeared more mature than non-occluded lungs. Tracheal occlusion earlier in gestation produced a greater effect, achieving greater than normal values for lung volumes and volume densities, whereas the capillary loading value was similar to normal lung. Later occlusion achieved less than normal values for lung volumes and volume densities, with a reduced capillary loading value. We conclude that antenatal tracheal occlusion is capable of reversing structural total lung and lobar hypoplasia and immaturity caused by CDH as determined by morphometrically determined parameters. The effect is greater when tracheal occlusion is performed early rather than late in gestation. The results are encouraging for development of treatment methods for humans with antenatally diagnosed CDH.
Subject(s)
Hernia, Diaphragmatic/embryology , Lung/embryology , Trachea/surgery , Animals , Cell Count , Evaluation Studies as Topic , Female , Fetal Organ Maturity , Hernias, Diaphragmatic, Congenital , Lung/cytology , Lung/growth & development , Morphogenesis , Pregnancy , Pulmonary Gas Exchange , Random Allocation , SheepABSTRACT
Congenital diaphragmatic hernia (CDH) in humans is relatively common and associated with high mortality attributed mainly to pulmonary hypoplasia. Previous animal models have induced CDH late in gestation, in contrast to the human situation, and only limited morphometric analyses have been reported. We undertook early surgical creation of CDH in fetal lambs, days 72-74 of gestation (n = 8), with unoperated lambs (n = 8) as controls. At 143 days (term = 145-149) a cesarean section was performed and the lungs were obtained, inflation fixed, divided into lobes, and processed for morphometry. In the CDH group the total lung volumes (51.3 mL compared to 223.8 mL) and gas exchange surface areas (5.85 m2 versus 26.43 m2) were less than one quarter of control values. Capillary loading was reduced from 0.3 mL/m2 in controls to 0.12 mL/m2 in CDH and parenchymal volume reduced from 77% in controls to 57% in CDH. Within parenchyma, gas exchange tissue volume was increased in CDH (66%) compared with controls (50%). CDH lungs had primitive air sacs/alveoli that were smaller (perimeter 83 microns) and more numerous (1321 per mm2) than in controls (perimeter 132 microns, 504 per mm2). The left lung and left upper lobe were affected most. Induction of CDH in the lamb at this early age results in quantifiable, reproducible pulmonary hypoplasia from which comparisons can be made with the human condition.