Relationship between Electroencephalography and Magnetic Resonance Imaging Findings after Hypoxic-Ischemic Encephalopathy at Term

Abstract

Hypoxic-ischemic encephalopathy (HIE) is a major cause of neonatal morbidity and mortality. Electroencephalography (EEG) and brain magnetic resonance imaging (MRI) are frequently performed in these infants, but the prognostic value of the combined use of EEG and MRI needs additional exploration. The purpose of this study was to investigate, in neonates with HIE, the role of early EEG and conventional MRI in the prediction of infants at risk for persistent encephalopathy at 18 months of age. Thirty-four term infants with HIE were enrolled in this prospective study. EEG was recorded within the first 72 hours after birth and a brain MRI scan was done between 1 and 4 weeks of age. Denver Developmental Screening Test II was performed at 6, 12, and 18 months of age. Three infants (9%) had mild HIE, 21 infants (62%) had moderate HIE, and 10 infants (29%) had severe HIE. The EEG background was normal, moderately, severely, and extremely discontinuous in eight (24%), three (9%), sixteen (47%), and seven (20%) neonates, respectively. EEG background activities correlated significantly with HIE severity (p = 0.0001). MRI findings significantly correlated with EEG background (p = 0.001). Normal MRI scans and minimal basal ganglia lesions were always associated with normal EEG background. Patients with severe basal ganglia and thalamic lesions in MRI (n = 2) had extreme discontinuous EEG background. For the prediction of poor outcomes, abnormal EEG background activity had a sensitivity (Sn) = 100%, a specificity (Sp) = 100%, positive predictive value (PPV) = 100%, and negative predictive value (NPV) = 100%, whereas values of abnormal MRI scans were Sn of 100%, Sp = 43%, PPV = 82%, and NPV=100%. EEG background activity is the best element to predict abnormal outcomes. Severe basal ganglia and thalamic injuries on MRI scans are associated with poor outcomes. Otherwise, MRI does not contribute to the prediction of outcomes at 18 months of age.

Difüzyon ağırlıklı ve konvansiyonel manyetik rezonans görüntülemenin hipoksik iskemik ansefalopatili yenidoğanlarda seyrin belirlenmesindeki etkinliğinin karşılaştırılması

“…In some studies, the value of conventional cranial MRI in indicating the long-term neurologic prognosis in patients with a diagnosis of HIE was investigated. According to the results of all these studies the sensitivity of CBMRI in determining the long-term neurologic prognosis was found to be 38-100%, the specificity was found to be 43-100%, the positive predictive value was found to be 75-100% and the negative predictive value was found to be 67-82% (13)(14)(15)(16). In contrast to all these, Van Schie et al (17) reported that involvement of basal ganglia, thalamus, cortex and posterior limb of the internal capsule on MR imaging was not related to motor development at one year of age in patients with a diagnosis of HIE.…”

“…With CBMRI brain lesions developed in infants with HIE can be determined at an early time (14). Therefore, imaging is recommended on the 2-8 th days (10)(11)(12).…”

MRI and Withdrawal of Life Support From Newborn Infants With Hypoxic-Ischemic Encephalopathy

“…[21][22][23] Nine of the 32 studies in the meta-analysis included only surviving infants with HIE, which made their results potentially less relevant to questions about withdrawal of intensive care. [24][25][26][27][28][29][30][31][32] …”

“…Some performed scans in the first days of life, 21,33-37 whereas others deferred imaging until after the first week. [24][25][26][27][28]38 However, the timing of imaging may be crucial if it is to be used in treatment-limitation decisions. 39 In infants with moderate or severe encephalopathy in cooling trials, the majority of deaths relating to withdrawal of treatment occurred in the first 3 or 4 days of life.…”

“…Barnett et al 51 (2002) Moderate or severe BG, severe WM Death, spastic quadriplegic CP, dystonic/athetoid CP Biagioni et al 25 (2001) Moderate or severe BG, severe WM Quadriplegic or dystonic CP, DQ Ͻ 50, CP unable to sit, or death El-Ayouty et al 24 (1996) Abnormal BG or multiple areas of WM infarction Dystonic/quadriplegic CP, "severe developmental delay" Rutherford et al 18 (1998) Bilaterally abnormal PLIC DQ Ͻ 50, death Rutherford et al 63 (2010) Moderate/severe BG, severe WM, abnormal PLIC MDI Ͻ 70 or GMFCS 3-5 or bilateral cortical visual impairment with no useful vision van Schie et al 30 (2007) Abnormal signal in the entire cortex and BG or abnormal PLIC Dystonic or quadriplegic CP or DQ Ͻ 55…”