Silent infarcts have been reported most commonly in school-aged children with homozygous sickle cell disease (SCD-SS) and are associated with neurocognitive deficits. However, the prevalence of silent infarcts in younger children with SCD-SS is not well defined. In this retrospective study, brain magnetic resonance imaging and angiography (MRI/A) studies performed before 6 years of age in a cohort of children with SCD-SS were analysed and the prevalence of abnormalities was calculated. Clinical and laboratory parameters were compared between the groups with and without silent infarcts. Sixty-eight of 96 children in the cohort had brain MRI/A performed prior to age 6 years. Of the 65 who were neurologically asymptomatic, 18 (27.7%, 95% CI 17.3-40.2%) had silent infarcts (mean age 3.7 +/- 1.1 years, range 1.3-5.9 years). Factors associated with silent infarcts included cerebral vessel stensosis by magnetic resonance angiography, lower rates of vaso-occlusive pain and acute chest syndrome and lower haemoglobin levels. The prevalence of silent infarcts in young children with SCD-SS is similar to that of older children and anaemia and severe vasculopathy may be risk factors.