Objectives: To evaluate US findings of basal ganglia and thalamus in term infants with hypoxic-ischemic encephalopathy and to correlate them with involved patterns, follow-up findings, and prognosis.
Materials and Methods: We reviewed the US findings of 13 full-term infants who were suspected to have hypoxic-ischemic encephalopathy. All the patients were examined by neurosonography within 1 week of onset. All cases also had follow-up neurosonography (n=11), follow-up CT scans (n=4), or MRI (n=7). We retrospectively analyzed and grouped the involved patterns into three types, including diffuse, unilateral, and focal pattern. Prognosis was defined by neurologic or developmental examination for age.
Results: Nine patients of diffuse pattern showed bilaterally-increased echogenicities at the basal ganglia, thalamus and surrounding brain parenchyma, and slit ventricle suggesting brain edema on early neurosonography. Follow-up neurosonography showed increased echogenicity, ventriculomegaly, and multicystic encephalomalacia. One patient of unilateral pattern, caused by thromboembolism, showed increased echogenicity on the right basal ganglia, thalamus and cerebral hemisphere. Three patients of focal pattern were confirmed by lacunar infarction through follow-up studies. Among nine patients of diffuse pattern, one patient died within 2 days after onset, two were discharged against advice and six have severe neurologic handicap. One patient of unilateral pattern has a moderate neurologic handicap and three patients of focal pattern are within a normal neurological developmental course.
Conclusion: Involved pattern of basal ganglia and thalamus in term infants with hypoxic-ischemic encephalopathy correlates with the prognosis. Therefore it could be helpful for the management of hypoxic-ischemic encephalopathy.