384 Outcome at 18 Months of Age After Sildenafil Therapy for Refractory Neonatal Hypoxemia

Abstract

Until recently lean mass and adipose tissue mass in infants and adults have been estimated by indirect methods. The use of magnetic resonance imaging has allowed direct measurement of these two components. There are no published data on normal values of adipose tissue and lean body mass in healthy term infants at birth using this technique. We carried out whole body adipose tissue (AT) magnetic resonance imaging. Individual volumes of subcutaneous, intra-abdominal and other internal adipose tissue were quantified and these summated to derive total AT. We converted total AT volume to adipose tissue mass and subtracted this from the body weight to derive the lean body mass. We expressed lean mass as a ratio of adipose tissue mass. Total adipose tissue mass is expressed as a percentage of body weight (%ATM) and the individual compartments of adipose tissue as a percentage of total adipose tissue volume. The local research ethics committee approved the study and written parental consent was sought. Results are expressed as mean (sd). 20 healthy appropriately grown Caucasian infants were studied within a week of birth. Their gestational age at birth was 39.9 (1.4) weeks. The %ATM in this group was 17.7 (2.6). Of the total adipose tissue, 91.9 (1.2) % was in the subcutaneous compartment and 3.1 (0.5) % was deposited intra abdominally. The lean to adipose tissue mass ratio was 4.8 (0.9). No significant differences were noted between male and female babies in any of the results. Normative data on body composition in the term infant has relied on data obtained either by whole body chemical analysis carried or derived from indirect measures of lean mass and fat mass. We have presented data from normal healthy term infants of similar ethnic origin using a novel technique to study body composition. PRETERM INFANTS AT TERM SHOW INCREASED INTRAHEPATOCEL-LULAR LIPID CONTENT ON PROTON MAGNETIC RESONANCE SPEC-TROSCOPY IMAGING SCIENCES DEPT, CLINICAL SCIENCES CENTRE, HAMMERSMITH HOSPITAL, LONDON (UK)Proton magnetic resonance spectroscopy (1H MRS) offers a non-invasive means to quantify intrahepatocellular (IHCL) lipid content which until recently was only possible using liver biopsy. Non alcoholic fatty liver disease is a spectrum varying from fatty infiltration to cirrhosis. The prevalence of this condition is increasing worldwide and is increasingly being reported in younger populations. Increased IHCL is associated with obesity, particularly intra-abdominal adiposity, insulin resistance and type II diabetes. We have shown that adipose tissue (AT) distribution is altered in the preterm infant at term, with increased intra-abdominal AT. The aim of this study was to establish the feasibility of investigating IHCL deposition in infants using 1H MRS. Whole body MR AT imaging was performed as previously described on a 1.5T Eclipse system. Preterm infants were studied at term and term infants in the first week. Hepatic 1H MR spectra were obtained using a PRESS sequence (TR 1500ms, TE 135ms). We employed one way analysis of variance....