UCSF

Background

To evaluate the predominant pattern of brain injury and the anatomic areas of injury in children with infantile spasms following neonatal hypoxic-ischemic encephalopathy.

Methods

A nested case-control study of infantile spasms in children with term neonatal hypoxic-ischemic encephalopathy was performed. All patients had T1/T2-weighted magnetic resonance imaging with diffusion-weighted imaging performed on the third day of life. Using a validated scoring system, the magnetic resonance imaging was classified as: normal, watershed, basal ganglia/thalamus, total, or focal-multifocal. Two study investigators scored additional anatomic areas of injury (cortical extent, levels of the brainstem, hypothalamus) on T1/T2-weighted magnetic resonance imaging and diffusion-weighted imaging blinded to the outcome. The predominant pattern of brain injury and anatomic areas of injury were compared between patients who developed infantile spasms and randomly selected controls.

Results

Eight patients who developed infantile spasms were identified among a cohort of 176 term newborns with hypoxic-ischemic encephalopathy (4.5%). There were no significant differences in the perinatal and neonatal course between newborns who developed infantile spasms and controls who did not. The development of infantile spasms after neonatal hypoxic-ischemic encephalopathy was significantly associated with basal ganglia/thalamus and total brain injury (P = 0.001), extent of cortical injury greater than 50% (odds ratio = 11.7, 95% confidence interval = 1.1-158.5, P = 0.01), injury to the midbrain (odds ratio = 13, 95% confidence interval = 1.3-172, P = 0.007) and hypothalamic abnormalities (P = 0.01).

Conclusions

The development of infantile spasms after hypoxic-ischemic encephalopathy is associated with injury to the basal ganglia and thalami on neonatal magnetic resonance imaging, particularly when extensive cortical injury and/or injury to the midbrain is present.