Neurobehavioral alterations in an adolescent following posterior fossa tumor resection.

The posterior fossa syndrome (PFS) consists of a variety of symptoms, including cerebellar mutism, behavioral disturbances and personality changes. We report longitudinal clinical, neuroradiological and neurobehavioral findings in a 19-year-old left-handed patient, diagnosed with attentional deficit hyperactivity disorder (ADHD) at the age of 12, who underwent posterior fossa tumor resection. Although the patient did not develop cerebellar mutism after surgery, marked apathy and emotional indifference, urinary retention, eye-lid apraxia and visual hallucinosis became apparent after a brief interval of normal functioning. Based on these findings it is argued that the PFS might be considered a semiological heterogeneous condition with variable clinical expressions. Long-term follow-up investigations revealed subtle, but significant cognitive and affective deficits, resembling the cerebellar cognitive affective syndrome in adults. As demonstrated by functional neuroimaging studies with SPECT, symptoms were associated with perfusional deficits in the anatomoclinically suspected supratentorial regions, reflecting the distant impact of the cerebellum on cognitive and affective functions.