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The accurate prenatal diagnosis of anterior abdominal wall defects is important because it affects patient management and prognosis. The pathophysiology of each defect leads to key characteristics that make it possible to differentiate one entity from another. Among these features are the location of the defect in relation to cord insertion, the size and contents of the defect, and the associated anomalies. This article reviews the underlying defects, the characteristic ultrasound findings, the associated anomalies, and the prognosis of simple and complicated abdominal wall defects. The basic features of simple abdominal wall defects (i.e., omphalocele and gastroschisis) were used as the initial points of assessment. A comparison of the different features of these abnormalities and how they differ from one another resulted in the development of criteria that facilitated the understanding of the different ultrasound manifestations of these anomalies.

Background: Outcome for most abdominal wall defects is related to the presence or absence of additional anomalies or prematurity. In gastroschisis, outcome is almost as closely related to the severity of the inflammatory "peel" on bowel that is thought to result from direct contact with amniotic fluid. Improving eviscerated bowel quality would be expected to reduce morbidity in these patients., Methods: From 1986 to 1991, 32 patients with the antenatal diagnosis of gastroschisis were treated. All were delivered by cesarean section; 13 surgical repairs were made immediately in the delivery room. Surgical repairs in 19 patients were made at less than 6 hours of age after transfer from the delivering hospital to the pediatric surgery center., Results: Thirty percent of infants who underwent surgical repair in delivery room and 32% of infants who underwent urgent surgical repair were either premature or had significant associated anomalies. Seventy-three percent of delivery room repair group had fascial repairs compared with 37% in the transferred group. When infants more than 34-weeks' gestation without associated anomalies are compared with transferred infants, delivery room repair group underwent more frequent fascial repair (8 of 9 vs 5 of 13, p < 0.03), were extubated sooner (2.9 vs 7.4 days, p < 0.04), tolerated enteral feedings earlier (8.1 vs 22.2 days, p < 0.009), and required fewer hospital days (13.6 vs 31.3 days, p < 0.01). Eviscerated bowel of infants who underwent immediate surgical repair lacked the characteristic matted, edematous, and fibrinous coated appearance seen in transferred patients., Conclusions: Immediate delivery room repair of gastroschisis results in increased fascial repairs and earlier extubation, feeding, and hospital discharge. These benefits appear to be due to the minimal reactive peel on eviscerated bowel at birth.

Diffuse neonatal hemangiomatosis is a rare, frequently fatal disease characterized by multiple cutaneous and visceral hemangiomas. The skin, liver, lungs, intestines, and central nervous system are the most commonly affected organs. Death can result from high-output cardiac failure as a result of arteriovenous shunting. In this report we present a new constellation of findings in a patient with diffuse neonatal hemangiomatosis, namely, an absent corpus callosum, ectopia cordis (sternal agenesis) with median abdominal raphe, and tricuspid atresia.

We describe seven female patients with deficient abdominal wall musculature and urinary tract and genital anomalies that represent the female equivalent of the prune belly syndrome. Urethral atresia, uterine duplication, and anorectal anomalies occurred frequently. The perinatal mortality rate was high; of the four surviving patients, renal failure developed in two and renal transplantation was required. The analysis of these cases suggests that urethral obstruction is an important factor contributing to the development of the prune belly syndrome in females.

Gastroschisis complicated by intestinal atresia is a complex problem. Six cases are presented. A review of the literature and of our own cases shows a high mortality rate. Success or failure is related more to the pathology present than to any specific method of operative management. Resection and primary anastomosis is the favored method of treatment, as the intestine heals well in spite of its appearance. Primary closure of the abdominal wall musculature and skin is done whenever possible. A gastrostomy is used uniformly. Intravenous hyperalimentation is critical to survival of these babies and should be used early. The use of this therapeutic modality allows for the onset of gastrointestinal function spontaneously (often over prolonged periods of time) without nutritional deprivation. Intestinal atresias almost always are easy to identify in babies with gastroschisis. Extensive dissection and mobilization of this friable intestine is contraindicated in those babies in whom an atresia is not obvious but only suspected. In such cases the gastroschisis defect should be managed by whatever method is deemed appropriate and the baby observed while receiving intravenous nutritional support. If an atresia is present, it can be managed later in the baby's course by resection and primary anastomosis.

Recent clinical reports suggest that the majority of neonates with gastroschisis are best managed with a silon pouch technique. Our results with primary closure and short-term ventilatory assistance show a survival rate equal to that of the silon pouch technique. In addition, multiple operations and the chances of complications related to the pouch are avoided. No complications relating to the ventilatory assistance were encountered. Better pediatric ventilators and improved pediatric respiratory management allow this technique to be used for gastroschisis now, whereas 10 years ago the complications ith neonatal ventilators may have outweighed the morbidity of the silon pouch.

Recognition of the disruptive vascular nature of the structural defects associated with gastroschisis and an appreciation of the embryology of the umbilical region suggest that gastroschisis results from an intrauterine interruption of the omphalomesenteric artery. This mechanism accounts for the usual location of gastroschisis to the right of the umbilical cord, the integrity of the rectus muscles in affected children, and many of the clinically observed differences between gastroschisis and omphalocele. The vascular basis of this defect explains its negligible recurrence risk and should alert the clinician to the possibility of concomitant structural defects of a similar pathogenesis.

Abdominal muscle deficiency with a "prune belly" abdomen as been a major feature of the so-called prune belly syndrome, which has been regarded as a specific entity, although the etiology and developmental pathology are not understood. We present evidence that abdominal muscle deficiency is an etiologically nonspecific anatomic defect which is secondary to fetal abdominal distention of various causes. One of the more common causes is urethral obstruction with consequent early bladder distention, causing abdominal distention and other anomalies, a constellation of findings which we have termed the urethral obstruction malformation complex. This interpretation of the etiology of most cases of prune belly syndrome accounts for the male predominance, the observed variability in severity, and the lack of a defined mode of inheritance. Recurrence risk figures need to be redefined for each specific obstructing lesion of the urethra. The possibility of early prenatal diagnosis and management of fetuses with urethral obstruction needs further study.

The features of 27 cases of limb/body wall deficiency (formerly termed cyllosomus and pleurosomus) were evaluated and the anomalies were interpreted as being band-related defects and/or compression-related defects. The latter included limb deficiency, body wall deficiency, neural tube defects, scoliosis, postural deformations, growth deficiency, and short umbilical cord. It is hypothesized that the single event of early amnion rupture can explain both the band-related defects and the compression-related defects. Experimental animal studies are in accord with this hypothesis; amnion puncture of rat fetuses during early gestation produces a comparable array of defects. The term amnion rupture sequence is suggested to describe the overall pattern of malformation that results from amnion rupture whether these defects are band related, compression related, or a combination of the two. There is considerable variation in the phenotype of amnion rupture sequence, with limb/body wall deficiency representing the more severe end of the spectrum. It is important to recognize and correctly diagnose amnion rupture sequence because it is usually a sporadic event.

Primary tissue closure of gastroschisis remains controversial. Some surgeons routinely place a silicone rubber sheet silo over the exposed bowel, planning a staged closure. In the past 14 1/2 years, we have cared for 106 newborns with gastroschisis, closing the defect primarily in 80%. The success of this technique depends on enlarging the abdominal cavity and decreasing the volume of bowel that must be replaced in the peritoneal cavity. Thorough preoperative rectal irrigation should evacuate all meconium. After undermining the skin around the abdominal wall defect for only 1 cm, a midline subcutaneous fasciotomy is created from the xiphoid to the pubis. The abdominal wall is then stretched in all quadrants beginning at the flanks. The eviscerated small bowel can often be returned without enlarging the initial skin defect. The skin is closed with subcuticular absorbable sutures reinforced by long skin tapes. The small ventral hernia that results is closed at about 1 year of age. Fascia could be closed primarily in 28% of these patients, and 17% required a prosthetic pouch. The duration of postoperative ileus and length of hospital stay were statistically significantly shorter in the infants who underwent primary closure. Even though more complicated patients were included in the primary closure group, the incidence of mortality and morbidity was not higher than in patients treated with silicone rubber pouches. Deaths were inevitable in five infants with gangrenous bowel, multiple anomalies, and extreme prematurity. Deaths were related to sepsis in three infants and were the result of operative or anesthetic technique in four. Only two preoperative factors were prognostic of morbidity and mortality: gestational age (but not birth weight) and the presence of intestinal ischemia or atresia.