Long-term neurodevelopmental outcome of preterm infants with cerebellar hemorrhages detected only on MRI was studied at University of California, San Francisco. Of 131 preterm newborns evaluated by cranial ultrasound and MRI, cerebellar hemorrhage was seen on ultrasound in 3 and confirmed on MRI. An additional 10 cerebellar hemorrhages not detected by ultrasound were seen on MRI. Three newborns died in the nursery, 2 with ultrasound-detected cerebellar hemorrhages. Of 128 survivors, 94 underwent periodic neurodevelopmental exams until age 3-6 years (mean 4.8). Of 8 newborns with cerebellar hemorrhage seen only on MRI and assessed at age 3-6 years, 4(50%) had abnormalities on neurologic examination, including hypertonia and hyperreflexia, but without ataxia or disturbed ambulation. Of 85 without cerebellar hemorrhage, 14 (16%) had abnormal neurologic exams, including truncal hypotonia and lower limb hypertonia and hyperreflexia. Cerebellar hemorrhage detected only by MRI was associated with a 5-fold increased odds of abnormal neurologic exam compared with newborns without cerebellar hemorrhage. WPPSI-III scores were unaffected. 
COMMENT. Cerebellar hemorrhage in preterm newborns and seen only on MRI may be associated with neurologic abnormalities but the outcome is generally favorable. In contrast, cerebellar hemorrhage detected by cranial ultrasound has a poor prognosis.