Clinical and neuroimaging characteristics in mild-type infantile acute subdural hematoma. Report of four cases

Purpose: Infantile acute subdural hematoma (IASDH) has a limited age distribution and mostly benign clinical features. Mild-type IASDH has a stereotypical clinical course which, however, has been described in only a few studies. Methods: Four male infants (aged 6–10 months; mean age: 7.5 months) were diagnosed as mild-type IASDH associated with retinal hemorrhage (RH) after suffering from occipital impact in a fall. The present case series reviews their clinical features and neuroimaging findings, including CT and MRI findings. Results: All the infants fell backwards from a standing or sitting position onto a soft surface, striking the occipital region. They began crying on impact, then soon afterwards exhibited seizure-like activity or recurrent vomiting. CT and MRI revealed a thin, unclotted subdural hematoma (SDH) without mass effect or brain parenchymal abnormality. Various degrees of bilateral retinal hemorrhage (RH) were observed. On the day of symptom onset, all infants returned to baseline, and follow-up more than 5 years revealed normal development with no deficits. Conclusions: Mild-type IASDH with retinal hemorrhage presents with seizure-like activity or recurrent vomiting preceded by crying after an occipital impact on a soft surface. The clinical course of IASDH is followed by rapid recovery on the day of symptom onset. CT and MRI findings reveal a small, unclotted subdural hematoma (SDH) without a mass effect or cerebral parenchymal abnormality.