Background and Purpose-In neonates, the differentiation of stroke and hypoxic ischemic encephalopathy (HIE) is important. Neuroimaging presents technical challenges in unstable neonates, resulting in frequently delayed or missed diagnosis of stroke. Differentiating clinical and electroencephalographic (EEG) features would assist physicians in the timely diagnosis. We sought to determine, in neonates with seizures, clinical and EEG features that differentiate stroke and HIE. Methods-Retrospective cohort study comparing clinical, seizure, and EEG features in term neonates with ischemic stroke or HIE and seizures within 7 days after birth, admitted at The Hospital for Sick Children. Putative clinical and EEG predictors of stroke were analyzed with univariate and multivariate methods. Results-Sixty-two newborns with stroke (nϭ27) or HIE (nϭ35) were studied. With univariate analysis, predictors of stroke included delayed seizure onset (Ն12-hours after birth) (PϽ0. Key Words: acute care Ⅲ EEG Ⅲ hypoxix ischemic encephelopathy Ⅲ predictors of diagnosis Ⅲ cereberal infarction Ⅲ neonates S eizures occurring in the neonatal period may be the manifestation of a serious underlying brain insult. The etiologic diagnosis of neonatal seizures is necessary to permit accurate decisions regarding management and prognosis. The incidence of seizures in neonates ranges from 0.15% to 3.5%, with most occurring within the first week of life. 1-3 Although neonatal seizures can result from transient metabolic derangements such as hypoglycemia or hypocalcaemia, hypoxic ischemic encephalopathy (HIE) accounts for as many as 60% to 65% 4 and ischemic stroke for 12% to 20%. 5,11,12 Stroke is frequently misdiagnosed as HIE because of overlapping clinical features. 9,10 In neonates with stroke, seizures are the only manifestation in 70% to 91% 1-5 and hemiparesis is uncommon (20%). 13 Generalized neurological abnormalities including encephalopathy can be present in both HIE and stroke. The prognosis and clinical management of neonatal stroke and HIE are very different. 6 -12 Early identification of these conditions maximizes opportunities for disease specific management strategies. The current approach for differentiating neonatal stroke and HIE relies on neuroimaging. Neuroimaging, however, is not straightforward in neonates who, when unstable, can be difficult to safely transport and image with CT (computed tomogram) and preferably MRI. 13,19 In neonates, cranial ultrasound is a useful noninvasive easily accessible intervention for the evaluation of both HIE and focal brain lesions such as stroke. However, it may not accurately diagnose stroke. 15,16 In addition, an early CT and MRI without diffusion may be normal in neonates with ischemic injury. 20 Electroencephalograph (EEG) is often the first diagnostic tool used to evaluate seizures, howeve, the utility of clinical seizure and EEG features in ascertaining the cause for neonatal seizures is not well established.
Study Design and MethodsTerm neonates with clinical seizures and a diagnosi...