Evaluation of perinatal hypoxic encephalopathy with advanced MR sequences

Abstract

Perinatal hypoxic ischemic encephalopathy (HIE) among important causes of neurological morbidity and mortality in full-term neonates. Identifying ischemic injury clinically usually is difficult in the immediate postnatal period, nonspecific clinical features are present and consid-erations regarding initiation of active life preserving therapies are needed. MR imaging is the most sensitive and specific imaging tech-nique available for the assessment of perinatal birth asphyxia related brain injury in term-born neonates. This study investigates the utility of MR spectroscopy peak ratios, ADC values along with conventional MRI. To compare the association of encephalopathy following hypoxia in term neonates with proton MRS ratios and ADC values. Conventional MRI (T1 and T2) along with DWI followed by MR Spectroscopy was done in 25 term neonates with clinical and neurological features of en-cephalopathy following perinatal asphyxia. MRS peak ratios, DWI with ADC values and conventional MRI findings were compared with each grade of HIE. Among 25 patients suspected cases of hypoxic enceph-alopathy, 15 patients had early positive conventional MR findings, 16 patients had late positive conventional MR findings, 19 patients had positive DWI, and 22 patients had positive MRS with high lac-tate/choline and lactate/NAA ratio. Higher association was found be-tween spectroscopy findings and hypoxic ischemic injury compared to MR imaging and ADC. The combination of MRS, DWI with ADC values and conventional MRI may assist in localizing and predicting the severi-ty of ischemic injury in HIE patients.