Cerebral cavernous angiomas (CCA) are rare, reportedly accounting for only 1% of all intracranial vascular lesions and 15% of all cerebral vascular malformations. Forms are sporadic or familial, and the mode of inheritance is probably autosomal dominant. We report an unusual case of an infant born at 37 weeks of gestational age following a normal pregnancy. Her birth-weight was 1560 g. The family history was negative. At 10 months of age, the child presented with the sudden onset of muscular hypotonia, motility and strength deficits, and absence of osteotendinous reflexes in the right arm. The psychomotor development of the child was normal. MRI revealed the presence of a cavernous angioma in the paramedian pontine region. The child's monoparesis quickly disappeared. This case is interesting because of the age at onset and the way in which the clinical manifestations developed.