The Efficacy of Fetal Ultrasonography and Postnatal Abdominal Ultrasonography for the Diagnosis of Neonatal Abdominal Mass

PURPOSE: Most neonatal abdominal masses are benign in nature, but early detection and management is important to avoid the development of complications. So, we studied the causes of neonatal abdominal masses and the efficacy of ultrasonography for early detection and diagnosis. METHODS: We reviewed 36 newborn infants with abdominal masses who had been admitted to the nursery and Neonatal Intensive Cave Unit of Seoul National University Children' s Hospital from Jan. 1, 1989 to Dec. 31, 1995. RESULTS: The mean gestational age was 38 weeks and the male to female ratio was 22 : 14. All masses were benign and the most common etiology was hydronephrosis (41.7%). The following etiologies were multicystic dysplastic kidney, polycystic kidney, ovarian cyst, hemangioendothelioma, teratoma, meconium peritonitis, mesenteric cyst and intestinal duplication cyst. All except one were detected before the first 48hours, and among them, 32 cases (88.9%) detected antenatally. All patients except one who died shortly after birth, were examined by abdominal ultrasonography, and 31 of 35 masses (88.6%) had the same diagnosis of ultrasonography. Five cases had associated abnormalities in the opposite kidney and other organs. CONCLUSION: The most common etiology of neonatal abdominal masses was hydronephrosis and majority of masses originated from genitourinary system. Most abdominal masses were detected antenatally and abdominal ultrasonography was an efficient method for the diagnosis of neonatal abdominal masses.

Influence of Phototherapy on Incidence of Patent Ductus Arteriosus in Very Low Birth Weight Infants

PURPOSE: Patent ductus arteriosus (PDA) is a common disease in very low birth weight infants (VLBWI). Hemodynamically significant PDA increases the morbidity and mortality of premature infants. Based on experimental model, light inhibits the constriction of immature piglet's ductal rings. No specific mechanism adequately explains the effect of light on the relaxation of PDA. Several hypotheses, including activation of photosensitive metabolites, alterations in receptors, or alterations in prostaglandin metabolism, have been postulated. The purpose of this study was to evaluate the influence of phototherapy on incidence of PDA in VLBWI. Mehtods : Sixty-three infants with birth weights less than 1,500 gm from March 1994 to February 1996 who were admitted in NICU of Seoul National University Children's Hospital were included. Thirty-four infants from March 1995 to February 1996 were shielded with aluminium foils on left chest during phototherapy (Shield group) and twenty-nine infants from March 1994 to February 1995 were not shielded (No shield group : control group). We investigated the incidence and the perinatal risk factors of PDA. RESULTS: 1) The incidence of PDA was 18% in shield group and 41% in control group. There was statistically significant between the two groups (P<0.05). 2) There was not statistically significant between two groups with gestational age, birth weight, sex, delivery mode, etc. 3) The perinatal risk factors which were statistically significant were group and presence of respiratory distress syndrome (RDS), and use of artificial surfactant. With linear logistic regression analysis, only group (OR=8.3, 95% CI=1.17-58.69) and presence of RDS (OR=21.3, 95% CI=1.39-329.81) were proved to be related to the occurrence of PDA. CONCLUSIONS: We conclude that chest shielding during phototherapy is a simple and inexpensive method to decrease the incidence of PDA.