With the development of fetal ultrasonography, detection of fetal ovarian cysts has been increased. Although ovarian cyst formation during the perinatal period is a self limiting process, there is still considerable controversy regarding the best treatment of the fetal ovarian cyst. The purpose of this study is to evaluate the natural history of fetal ovarian cysts and to analyze the result of treatment. From 1995 to 2004, 31 consecutive fetuses with ovarian cysts were followed by ultrasonography during the perinatal period. The fetal ovarian cyst was diagnosed by prenatal ultrasonography between 25weeks and 38 weeks and the mean size of the cysts was 5cm (ranged from 2 to 8cm). At birth, 3 cysts disappeared. In 2 cases, the diagnoses were changed to multicystic kidney disease and intestinal duplication. During following up of 26 cysts, 15 cysts have resolved completely. Seven cysts required oophorectomy because of cyst torsion (n=3), differentiation of tumorous condition (n=2), increased size of cyst (n=1), and large size (8cm) of cyst at birth (n=1). Fetal ovarian cyst should primarily be observed, and only in the limited cases, surgical treatment would be required for the risk of complications such as torsion and differentiation from benign to malignant pathology.

Abnormal distribution of enteric nerves such as adrenergic, cholinergic and non-adrenergic non-cholinergic nerves (NANC) may cause the failure of relaxation at the involved bowel segment in Hirschsprung's disease (HD). Nitric oxide (NO) is a major inhibitory NANC neurotransmitter in the gastrointestinal tract. NO is synthesized by activation of nNOS (neuronal nitric oxide synthase) in the intramural ganglion cells and regulates bowel movement. To assess the distribution of nNOS in HD, immunohistochemical staining to nNOS was utilized on paraffin embedded specimens. Ten control colon specimens were tested for feasibility of staining. Immunohistochemisrty was done on ganglionic colon as well as aganglionic segment of 15 patients with HD. nNOS immunoreactivity was observed in the neuronal cells, small cells and nerve fibers in the muscle layer and submucosal neuronal cells of control specimens. This finding was also observed in the ganglionic segments of HD. But, there was no nNOS immunoreactivity in aganglionic segments of HD. In conclusion nNOS immunohistochemical staining of paraffin embedded specimen is feasible and reliable. And the results suggest that the relaxation failure of the aganglionic bowel in HD is related to the absence of nNOS containing cells and nerve fibers.

Choledochal cysts have been associated with complications such as cholangitis, pancreatitis, and malignancy of the biliary tract. Recently, the incidence of choledochal cyst in neonate and young infant is increasing due to advances in diagnostic imaging. The aim of this study is to investigate the rationale of excision of choledochal cyst during the neonatal period. The clinical outcome and correlation between age at surgery and the degree of liver fibrosis were reviewed retrospectively. A total of 198 patients with choledochal cyst who were managed surgically between January 1985 and December 2000 at the Department of Surgery, Seoul National University Children's Hospital were included in this study. The overall outcome and the outcome of patients who were managed surgically during the neonatal period were compared. Correlation between age and the degree of liver fibrosis was evaluated by chi-square test and Pearson exact test. The mean age of the patients was 2 years 7 months (ranged from 5 days to 15 years). Mean postoperative follow-up period was 7 years 1 month (7 months to 20 years). The results are as follows. Twelve patients (6%) had postoperative complications, cholangitis (7), bleeding (4) and ileus (1). Eleven patients operated during the neonatal period had no postoperative complications. The positive correlation between age group and degree of liver fibrosis was statistically significant (chi-square: p=0.0165, Pearson exact test: p=0.019). The results support the rationale that excision of choledochal cyst can be performed safely without increasing morbidity in neonates.

Infantile hypertrophic pyloric stenosis (HPS) is a relatively common entity. A number of studies for the postoperative feeding schedule has been studied to allow for earlier hospital discharge and improve cost-effectiveness in the treatment of HPS. The purpose of this study was to compare 3 feeding-methods and to evaluate the usefulness of ad lib feeding for HPS. The authors retrospectively reviewed the records of 116 patients who underwent pyloromyotomy for HPS from 1995 to 2004. Three cases were excluded because of the duodenal perforation during pyloromyotomy. Three feeding-methods were defined as: Conventional feeding (>10 hours nothing by mouth and incremental feeding every 2 hours, C), Early feeding(for 4 to 8 hours nothing by mouth and incremental feeding every 2 hours, E), and Ad lib feeding (for 4 hours nothing by mouth and ad lib feeding, A). Time to normal feeing in C, E and A were 51±24, 34±12 and 24±6 hours, respectively. Hospital-stay in C, E and A were 72±17, 55±13 and 43±12 hours, respectively. There were statistically significant differences according to the method of feeding. Frequency of postoperative emesis in C, E and A were 38%, 47% and 53%, but was not significant statistically. Ad lib feeding decreased time to normal feeding and hospital stay, and did not increase postoperative emesis. We conclude that ad lib feeding is recommended for patient with pyloromyotomy in HPS.

Two cases of primary torsion of the greater omentum were described. The first patient was a 5-year-old boy who was admitted to the hospital because of severe abdominal pain for 1 day. The The clinical features were similar to perforated acute appendicitis. Laparotomy revealed a normal appendix and the greater omentum twisted around its pedicle. The second patient was a 7-year-old girl admitted to the hospital because of abdominal pain in right lower quadrant for 2 days. The clinical features were that of acute appendicitis. Laparotomy revealed a normal appendix and primary torsion of greater omentum around its pedicle. In both cases, resection of twisted omentum and incidental appendectomy were done. The microscopic findings in two cases consisted of congestion and vascular hemorrhage. Both patients recovered uneventfully. Torsion of the greater omentum, therefore, may be added to the entities to consider in the differential diagnosis of acute appendicitis.

Solid pseudopapillary tumor of pancreas in children is a tumor with low malignant potentiality, and is rarely associated with distant metastasis. A 13-year-old girl was hospitalized because of abdominal pain of one week duration. Abdominal CT revealed not only a 12×6cm sized mass at the pancreatic body and tail but also a 1cm sized mass in left lobe of the liver. The patient underwent a near-total pancreatectomy and tumorectomy of the liver. A solid pseudopapillary tumor with liver metastasis was confirmed by pathology. She has undergone 13 courses of chemotherapy and has been well for 13 months without any sign of recurrence.

Solid and papillary epithelial neoplasm (SPEN) of the pancreas is a rare tumor with low malignant potentiality that usually occurs in young females. Preoperative evaluation, especially radiologic tests, including ultrasonography and CT scan, is helpful in the diagnosis. These studies demonstrate a well-demarcated large mass with solid and cystic portions, frequently in the tail or body of the pancreas. Complete resection is usually curative, however local invasion and/or metastasis may occur. The authors report a case of a solid and papillary epithelial neoplasm of the pancreatic body in a 14-year old child at St. Benedict Hospital and review the literature.