Obstructive internal hernia caused by mesodiverticular bands in children: Two case reports and a review of the literature.

INTRODUCTION: The mesodiverticular band (MDB) is an embryologic remnant of the vitelline circulation, which carries the arterial supply to the Meckel diverticulum. In the event of an error of involution, a patent or nonpatent arterial band persists and extends from the mesentery to the apex of the antimesenteric diverticulum. This creates a snare-like opening through which bowel loops may herniate and become obstructed. This report describes 2 rare cases of small bowel occlusion owing to an internal hernia caused by a MDB. CASES: Case 1 was a 5-year-old boy who presented to our Emergency Department with colicky abdominal pain diffused to all abdominal quadrants. He also had 5 episodes of emesis, the last with bilious vomiting. Case 2, a 12-year-old boy, presented to our Emergency Department complaining of colicky abdominal pain. He had 2 episodes of nonbilious emesis. On physical examination, both children showed distension and tenderness of the abdomen and abdominal x-ray and ultrasound confirmed an occlusive picture without an apparent etiology. In case 1, an urgent laparotomy was performed and the MDB was ligated and cut, whereas in case 2 diagnosis and excision were performed in laparotomy. In both patients, there was a positive clinical evolution. CONCLUSION: Although MDB causing internal hernia is very rare, it should be considered in patients with a clinical picture of small bowel obstruction. In these cases, early surgery is important to prevent strangulation and gangrene of the bowel and to avoid dramatic events. Moreover, laparoscopy seems a safe and effective technique in these patients, especially in children with mild abdominal distention without surgical or trauma history, highlighting that further studies on the value of laparoscopy for the treatment of small bowel obstruction in pediatric patients are urgently needed.

Embryogenesis and types of subcostal hernia--a rare entity.

BACKGROUND/PURPOSE: Four infants with congenital subcostal hernia are reported, as it is a rare entity with only two cases previously reported. Further, there are no reports concerning the complex multisystem subtype. Embryogenesis of the associated anomalies and subcostal hernia and their management are discussed. MATERIALS/METHODS: Clinical features, history, investigations, associated anomalies, and management data of four patients with subcostal hernia were collected and analyzed. RESULTS: The following associated anomalies were detected: renal agenesis (2), musculoskeletal abnormality (3), congenital heart disease (2), müllerian-renal-cervicothoracic somite abnormalities and vertebral-anorectal-cardiac-tracheoesophageal-renal-radial-limb anomalies (1). The subcostal hernias were treated by laparoscopic assisted (3) or laparoscopic herniorrhaphy (1). CONCLUSIONS: Subcostal hernia is a rare entity with varied clinical presentations and presents either as an isolated defect or as a complex multisystem defect. The exact etiology is still unknown. Phenotypic manifestation of the complex defect is probably due to developmental gene defect affecting the coordinated growth of mesoderm around 4th to 10th weeks of fetal life.

Increase in fetal pulmonary artery diameters during late gestation is a predictor of outcome in congenital diaphragmatic hernia with liver herniation.

AIM: Liver herniation (LH) in congenital diaphragmatic hernia (CDH) may not be a reliable prognostic indicator. We measured pulmonary artery (PA) diameters in CDH + LH as an alternative. METHODS: Of 41 consecutive cases of prenatally diagnosed left-sided CDH treated from 2002 to 2010, 19 had CDH + LH and 22 had CDH - LH. Ultrasonography and magnetic resonance imaging were used to assess LH and echocardiography to measure PA diameters during the third trimester (fetal; 32-34 weeks), at birth, and on day 2 of life. RESULTS: In CDH + LH survivors (9/19; 47%), fetal right PA (RPA) diameters were significantly larger than in nonsurvivors (2.58 ± 0.56 vs 1.82 ± 0.35 mm; P < .01), but left PA (LPA) diameters were not (1.73 ± 0.38 vs 1.59 ± 0.22). In survivors, fetal RPA was greater than 2 mm in all but one case, and both PA diameters increased significantly by birth (RPA, 2.58 ± 0.56 vs 3.52 ± 0.54; LPA, 1.73 ± 0.38 vs 2.60 ± 0.40; both P < .01). Final diameters at birth in survivors were at least 2.5 and 2.0 mm, respectively. In nonsurvivors, both PAs were significantly smaller (RPA, 3.52 ± 0.54 vs 2.04 ± 0.31; LPA, 2.60 ± 0.40 vs 1.68 ± 0.18; P < .01), with no observed increase by birth. Survival in CDH - LH was 82% (18/22). CONCLUSION: PA diameter appears to be correlated with prognosis in infants with CDH + LH.

Right paraduodenal hernia leading to bowel strangulation.

Up to half of all internal hernias are caused by paraduodenal hernia, a rare congenital midgut malrotation that accounts for less than 1% of all intestinal obstructions. The diagnosis may arise from an incidental finding on abdominal imaging or the patient may present with abdominal pain, vomiting, and obstipation. Early recognition and management of this disease entity are keys because serious complications such as bowel ischemia and infarction may result from a delay in diagnosis. We present a case involving a 14-year-old boy with gangrenous small bowel secondary to right paraduodenal hernia.

The embryology of the diaphragm.

Despite the progress in prenatal diagnosis and intervention as well as postnatal therapeutic strategies, congenital diaphragmatic hernia (CDH) is still associated with a meaningful mortality because of the induced pulmonary hypoplasia. An essential key in understanding the pathogenesis of CDH is the underlying embryology, which has been neglected during the last decades. Likewise, the development of the normal diaphragm is still poorly understood. Obsolescent perceptions, mainly formed from histologic sections, are still propagated. In this review we present an atlas of scanning electron microscopy images that depict the normal and defective development of the diaphragm in the nitrofen rat model for CDH. Our findings suggest that the normal diaphragm mainly develops from the posthepatic mesenchymal plate. If the development of the posthepatic mesenchymal plate is impaired, a diaphragmatic defect occurs.

Laparoscopic repair of a right paraduodenal hernia.

BACKGROUND AND OBJECTIVES: Right paraduodenal hernia (PDH) results from a primitive gut malrotation. The resultant jejunal mesenteric defect posterior to the superior mesenteric vessels allows decompressed jejunum to herniate retroperitoneally. PDH make up 53% of all internal hernias, but account for only 0.2% to 5.8% of all cases of intestinal obstruction. In addition, PDH exhibits male and left-sided predominance. Ours is the second report to describe the preoperative diagnosis and totally laparoscopic repair of a right PDH. METHODS: We report the case of a 26-year-old female with symptoms suggestive of partial small bowel obstruction and a 6-year history of intermittent abdominal pain. Physical examination demonstrated lower quadrant tenderness. Plain abdominal radiographs and ultrasonography were nondiagnostic. Contrasted computed tomography of the abdomen revealed jejunum encased within the right upper quadrant suspicious for right PDH. RESULTS: The patient underwent successful laparoscopic right PDH repair and was discharged home on postoperative day 1 without late sequelae. CONCLUSIONS: In the outpatient setting, clinical suspicion and comprehensive radiological investigation permit preoperative diagnosis of right PDH. In acute situations, clinical presentation, plain radiographs, and then diagnostic laparoscopy may be an expeditious diagnostic algorithm. Subsequent laparoscopic repair of right PDH is feasible and may shorten hospital length of stay.

Red herring: a rare cause of small bowel obstruction.

This is a case report of a 73-year-old man with a small bowel obstruction secondary to an incarcerated paracaecal hernia. His large right inguinal hernia, initially suspected as a potential source of obstruction, turned out to be a red herring. Congenital internal hernias are a very rare cause of bowel obstruction. In this report we review the literature and embryology behind these uncommon occurrences.

Assessment of fetal lung volumes and liver herniation with magnetic resonance imaging in congenital diaphragmatic hernia.

OBJECTIVE: We evaluated the use of fetal magnetic resonance imaging in predicting outcomes after ultrasonographic diagnosis of left-sided congenital diaphragmatic hernia. STUDY DESIGN: Forty-one pregnant women carrying fetuses with congenital diaphragmatic hernia underwent 43 magnetic resonance imaging scans. Lung volumes were calculated by summing the areas on 6-mm axial sections. The presence or absence of liver herniation was noted. A liver/diaphragm ratio was obtained by using the distances from the superior aspect of the liver and the diaphragmatic remnant to the apex of the chest. RESULTS: Mean gestational age was 26 weeks and overall survival was 59%. Neither right, left, nor total lung volume measurements were predictive of survival. Liver herniation into the left side of the chest was predictive of outcome at P<.05. The liver/diaphragm ratio was predictive of outcome at P = .03. CONCLUSION: Fetal magnetic resonance imaging permits calculation of lung volumes, but these volumes are not predictive of outcome. However, both the presence of liver herniation and the volume of liver within the chest, as reflected by the liver/diaphragm ratio, help predict outcome in left-sided congenital diaphragmatic hernia.

The retropancreatic colon: a congenital anomaly.

We report the first case of a retropancreatic colon. This condition appears to be a congenital internal intra-abdominal hernia secondary to abnormal intestinal rotation in the embryo.

[Intestinal obstruction caused by paracecal hernia. 3 case reports and review of the literature]. / Occlusione intestinale da ernia paracecale. Descrizione di tre casi e revisione della letteratura.

The authors report three rare cases of intestinal obstruction due to paracecal hernia observed in 533 small bowel obstructions operated between January 1982 and December 1994 (0.6%). In our experience, all the cases occurred in old female patients. Less than 150 cases are reported in the literature. The authors examine paracecal hernia embryologic aspects to explain its pathogenesis: the rotation of primary intestinal loop determines final intestinal rapports. Preoperative diagnosis is very difficult. Transitory symptoms may appear months or years before intestinal obstruction; these occurrences suggest that internal hernias, like external ones, may spontaneously reduce. Straight abdominal radiographies, performed in all cases here described, demonstrate small bowel levels. There is disproportion between important subjective symptoms and objective finding of a large round bump localized in the right iliac fossa. Authors underline the opportunity of a promptly performed operation: in all our cases we released the incarcerated intestinal loops and sutured hernial foramen. One exitus occurred, on the 4th postoperative day, probably due to pulmonary embolism.

Genetic analysis of the cause of gastroschisis in the HLG mouse strain.

An inbred mouse strain HLG shows a high incidence of gastroschisis after X-ray exposure to the zygotes. About 11% of the fetuses display this malformation after irradiation with 1 Gy. The C57BL-strain does not show the increased frequency of gastroschisis after radiation-exposure to the zygotes. The genetic background of this malformation was investigated in a backcross of HLG x C57BL females to HLG males. The pregnant HLG x C57BL females were irradiated in a stage in which the (HLG x C57BL) x HLG [BC1] embryos were in the 1-cell stage. The frequency of gastroschisis in the BC1 generation was compared with a genetic model of a single recessive mutation with 11% penetrance. This frequency does not fit a single-locus inheritance. The number of loci involved was estimated to be about two or three. HLG mouse strain may be a valuable animal model in the study of polygenic traits.

Fetal diaphragmatic hernia without visceral herniation.

Many cases of congenital diaphragmatic hernia (CDH) are currently detected before birth. The authors hypothesized that there is a subgroup of patients with CDH who have no evidence of visceral herniation in utero and who would be expected to have less pulmonary hypoplasia and a good prognosis. Among 41 neonates with left-sided CDH treated between January 1990 and October 1993, 17 cases were diagnosed after birth. Ten of the 17 had undergone detailed fetal sonographic imaging at or after 20 weeks' gestation. After independent review of the prenatal scans of these 10 patients, one was found to have evidence of a diaphragmatic hernia and was excluded from further analysis. The other nine fetuses survived, and prosthetic repair of the diaphragmatic defect and extracorporeal membrane oxygenation (ECMO) were each required in only one patient. This contrasted with the outcome for 18 control patients with prenatally diagnosed CDH: 4 (22%) died, 13 (72%) required prosthetic repair, 9 (50%) were supported with ECMO and the duration of ventilatory support and hospital stay were significantly longer. There is a spectrum of severity among both pre and postnatally diagnosed cases of CDH. In the neonate with an isolated left-sided diaphragmatic hernia, a good prognosis is to be expected if the condition was not detectable by detailed prenatal sonography in the second half of pregnancy.

Prenatal sonographic predictors of liver herniation in congenital diaphragmatic hernia.

We conducted a retrospective review of prenatal sonograms of all fetuses (n = 25) with left sided congenital diaphragmatic hernia undergoing in utero surgical repair of the defect at the University of California, San Francisco, Fetal Treatment Center. Sixteen candidates were selected for analysis to determine reliable predictors of liver herniation. Bowing of the umbilical segment of the portal vein (portal sinus) to the left of midline and coursing of portal branches to the lateral segment of the left hepatic lobe toward or above the diaphragmatic ridge were the best predictors for liver herniation into the fetal thorax (positive predictive values of 85% and 100%, respectively). The stomach position was a good predictor if observed in a posterior or midthoracic location (positive predictive value = 100%). However, this occurred in only 7 of 16 (44%) cases. Visibility of the right lung was less informative (positive predictive value = 63%). We do not recommend in utero primary closure of congenital diaphragmatic hernia when there is sonographic evidence of liver herniation into the fetal thorax.

Growth retardation in prenatally diagnosed cases of gastroschisis.

Gastroschisis is a rare congenital anomaly characterized by the herniation of fetal intestines directly through an abdominal wall defect. It is associated infrequently with chromosomal or other nonbowel defects and can be treated surgically after delivery, with survival rates reported to be between 87 and 100%. We reviewed 21 cases of prenatally diagnosed gastroschisis to ascertain the effect of fetal growth retardation on perinatal outcome. Ten of the 21 fetuses (48%) were identified prenatally as growth retarded, although only seven of these ten truly had birth weights less than the 10th percentile. Three additional fetuses that had not been identified prenatally as growth retarded did, in fact, have birth weights less than the 10th percentile, for a total frequency of growth retardation at birth of 48% (10/21 fetuses). When compared to non-growth-retarded fetuses with gastroschisis, fetuses who were growth retarded, although more likely to have been delivered by emergency cesarean section, had shorter hospitalization times, were more likely to have undergone primary closure on the first day of life, and had fewer major complications. We conclude that growth retardation is common in fetuses with gastroschisis and the postnatal outcome in gastroschisis is not poorer for fetuses who are growth retarded.

Paraduodenal hernias.

Although congenital paraduodenal hernias are infrequently encountered clinically, a surgeon must have knowledge of their production and anatomic relationships in order to properly manage these patients.

[Paraduodenal hernia (author's transl)]. / Paraduodenale hernia.

The internal paraduodenal hernia is a most unusual disorder of the alimentary tract, due to a failure of the process of intestinal rotation. There exists a right and left variety, each of them presenting specific features. Often there are no symptoms or perhaps a vague abdominal malaise. Occasionnally one finds the clinical picture of obstruction, even of strangulation. The preoperative diagnosis is seldom made; however, it could be done if one keeps the possibility in mind. A successful surgical treatment necessitates an understanding of the mode of origin and a throughout knowledge of the anatomic variations.