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Redmond et al.: Radiation to neural progenitor niches and neurocognitive outcomes

at Universitaet Leipzig, Institut fuer Informatik/URZ, Bibliothek on August 25, 2014 http://neuro-oncology.oxfordjournals.org/ Downloaded from

Fig. 2. Age- and time-related changes in neuropsychological performance (raw scores) in patients and controls. The black “ + ” symbols represent individual control data points and the gray “ × ” symbols represent individual patient data points. The results of the LME regression analyses of age- and time-related differences in test scores between patients and controls are presented as solid lines. The individual lines represent changes in test scores over time (27 mo) for patients (gray lines) and controls (black lines) of different ages. Raw scores in both groups increased with age on the Purdue Pegboard 2-Hand test (1A), WJ-III Memory for Words (1B), Bead Memory (1C), and visual perception test (1D) (all P , .001). Improvement in test performance on the Purdue Pegboard 2-Hand, WJ-III Memory for Words, and visual perception tests over the 27-mo period was most prominent in younger children. However, despite overall improvement over time, younger patients had more pronounced cognitive deficits.

P ¼ .033, visit: P ¼ .021; right temporal lobe, dose: P ¼ .015, visit: P ¼ .017). At 6-month follow-up, raw scores decreased with increasing doses to the left and right hippocampi and temporal lobes (for all, P , .045). At 15-month follow-up, the relationship was significant for the temporal lobes (left, P ¼ .020; right, P ¼ .010) and at 27-month follow-up, for the right hippocampus ( P ¼ .036). Figures 4 and 5 illustrate decreased motor speed / dexterity with increasing radia- tion doses to the hippocampi and temporal lobes, respec- tively, at 6-month follow-up. There was no significant effect of mean dose to cerebrum ( P ¼ .46) or SVZ ( P . .3) on performance. There was no significant difference in performance on the test of motor speed between patients with infratentorial versus supratento- rial tumors ( P ¼ .37 at 6 mo, P ¼ .55 at 15 mo, and P ¼ .59 at 27 mo). Verbal learning (WJ-III Memory for Words).— Although the main analysis for verbal learning indicated an overall effect of dose to cerebrum on test performance (dose, P ¼ .022; visit, P ¼ .013; Age RT × Dose,

addition, different rates of change in test performance were found over time in patients versus controls, such that the performance of patients improved toward normal over time. For example, the improvement over time was faster for patients than for controls on verbal memory but slower for patients than for controls on motor speed / dexterity. No significant group- or age-related differences were revealed for recognition vocabulary (these results are not included in Figs 2 and 3 ).

Effect of Radiation Dose on Neuropsychological Performance

Motor speed and dexterity (Purdue Pegboard 2-Hand).— Among patients, motor speed and dexterity decreased with increasing mean radiation dose to the hippocampus (main LME analyses: left hippocampus, dose: P ¼ .049, visit: P ¼ .023; right hippocampus, dose: P ¼ .032, visit: P ¼ .014). Test performance also decreased with increasing mean dose to the temporal lobes (main LME analysis: left temporal lobe, dose:

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