Role of transcranial USG in detection of brain insults in preterm and high risk term neonates

Abstract

BACKGROUND: Preterm neonates and term neonates with some underlying risk factors are at risk of abnormal neurological development caused by hemorrhagic, ischemic and inflammatory brain lesions. Hypoxic-ischemic encephalopathy (HIE) is a major contributor to neonatal neurological morbidity and mortality. Early detection of ongoing brain injury in these neonates is therefore important to implement or modify preventive treatment. The non-invasive nature of ultrasonography makes it an ideal imaging technique in the neonates and preterm infants.

OBJECTIVES: To assess the utility of ultrasonography to diagnose spectrum of brain injury in preterm and high risk term neonates  

PARTICIPANTS: 100 high risk neonates admitted to neonatal intensive care unit were selected as per the inclusion criteria on non-randomized purposive sampling basis and were subjected to transcranial sonography in the first week of life.

STUDY DESIGN: a prospective study

METHODS: Assessment of factors placing the neonate in a high risk category was done taking detailed maternal history and reviewing all antenatal records. All perinatal details were recorded and detailed clinical examination was done including anthropometric measurements. Vital parameters were recorded within 24-48 hrs of admission. Follow up cranial ultrasound was done in case of positive findings. Cranial ultrasound findings were analysed and recorded and clinical correlation with various findings on cranial ultrasound was done. Neonates were followed till recovery and discharge from NICU.

RESULTS: Out of 100 neonates, 38% neonates had abnormal USG findings and in 62% neonates USG findings were normal. Among neonates with abnormal USG findings, 30 (78.9%) were males and only 8 (21.1%) were females. Out of 38% , 17 % of these had evidence of intracranial bleed of which 11% had germinal matrix hemorrhage (grade 1) and rest had other grades of hemorrhage. 7% had cerebral edema, 5% had thalamic hyperechogenecity, 2% had periventricular leukomalacia (PVL) and 4% had congenital anomalies. Two neonates (2%) on regular follow up developed findings suggestive of cystic PVL correlating well with clinical outcome. Four (4%) neonates had congenital anamolies,of which two had dandy walker malformation, one had hydrancephaly and one had hydrocephalus with associated meningomyelocele.

CONCLUSION: CUS is an ideal imaging tool for the primary screening of the neonatal brain & is a critical investigatory modality in NICU while effectively documenting the morphological changes of brain damage.
IMPLICATION: CUS should be a primary diagnostic modality for screening neonates with high risk or at risk term & preterm group given its noninvasive, quick, cost effective & real time advantages.
KEYWORDS: CUS cranial ultrasonography, PVL periventricular leucomalacia, NICU neonatal intensive care unit, hypoxic ischemic encephalopathy