Evolution of hydranencephaly following intracerebral hemorrhage.

A circumscribed hyperechoic mass in the mid-portion of the left cerebral hemisphere was the presenting ultrasonographic finding in a 30-week fetus. With repeat ultrasound studies, this echo-dense mass became more sonolucent. In addition, there was an increased fluid accumulation and loss of identifiable cerebral cortex over the left parietal and occipital lobes. The patient underwent induction of labor because of progressive intracranial fluid accumulation with subsequent macrocephaly. The infant died on the fourth day of life. At necropsy, an organizing hematoma with admixtures of fresh and moderately degraded old blood was found in the left hemisphere. There was extensive resorption of the underlying cortex, leaving only a fluid-filled cavity with a meningeal covering. We believe the progressive changes that occurred after fetal intracerebral hemorrhage ultimately resulted in hydranencephaly.