Impairment of neuropsychological functions in children with medulloblastomas and astrocytomas in the posterior fossa

Abstract

Neuropsychological impairment after removal of posterior fossa tumors is a recurrent issue in child neuropsychology and neurosurgery. The aim of this study was to assess verbal and performance intelligence, as well as immediate and sustained attention, in children with medulloblastoma or astrocytoma operated on for total removal of the lesion. Surgical treatment of medulloblastoma was always followed by chemoradiotherapy. Siblings of both tumor groups (without a history of neurological disease, even suspected) were examined as controls. The results were as follows: the cognitive performances were significantly poorer than the controls in both groups; the children with medulloblastoma scored below normal. Attention deficits were present in both groups as well when the usual clinical tests were used. When assessed by means of computerized methodology, the same function was normal. Considering that both groups of children underwent the same surgical treatment and all had hydrocephalus, the severe intellectual impairment reported only in patients with medulloblastoma can be ascribed to chemoradiotherapy. In contrast, the attention deficits present in both groups could be ascribed to the proximity of lesions to the ascending activating system. Malfunctioning of the activating system seems to be bypassed by the computerized administration of stimuli, which supplies motivation and kindles attention.

Neuropsychological status of children treated for brain tumors: A critical review and integrative analysis

“…This association is difficult to evaluate because of differing definitions of "younger" age groups: below 3 years [15,21], 6 years [19,20,24], 7 years [ll], 7.5 years [12], and 8 years [14]. Statistically significant age effects were found in 4 studies [11,12,20,34]; the .other four investigations were purely descriptive [14,15,16,30].…”

Memory and attention after childhood brain tumors

“…Children with tumors in various brain locations exhibit some attention problems whether or not adjuvant radiation has been part of their treatment [14]. More particularly, children with posterior fossa tumors (medulloblastoma or astrocytoma) performed more poorly than sibling/cousin controls on clinical attention tasks, even though they produced as many correct responses as controls on simple and choice reaction-time tasks, possibly due to the proximity of the lesion to the brainstem ascending activating system [15]. At present, it is not clear whether the number of correct responses is due to a tendency to respond to any signal or whether children with posterior fossa tumors and controls are equally able to respond to targets and to inhibit responses to nontargets.…”

“…Figure 1 shows that the demands of selective attention were associated with better, not worse, performance in children with radiated brain tumors. In this context, it has been suggested that strong motivational activation improves attention in children with posterior fossa tumors [15]. The relation between attention performance and level of activation in childhood brain tumor survivors is an important issue that warrants more explicit investigation.…”

Changes in Cerebral Cortex of Children Treated for Medulloblastoma

“…These children often develop late neurocognitive sequelae, such as significant decreases in intellectual function (1)(2)(3)(4)(5)(6)(7)(8)(9)(10), poor academic performance (6,11,12), and deficits in attention (4,11,13), memory (4,11), verbal fluency (4,5,7,11), and executive functioning (11).…”