Search

Background: Improved survival for children with acute lymphocytic leukemia (ALL) has allowed investigators to focus on the adverse or side effects of treatment and to develop interventions that promote cure while decreasing the long-term effects of therapy. Although much attention has been given to the significant neurocognitive sequelae that can occur after ALL therapy, limited investigation is found addressing fine motor function in these children and motor function that may contribute to neurocognitive deficits in ALL survivors., Methods: Fine motor and sensory-perceptual performances were examined in 82 children with ALL within 6-months of diagnosis and annually for 2 years (year 1 and year 2, respectively) during therapy., Results: Purdue Pegboard assessments indicated significant slowing of fine motor speed and dexterity for the dominant hand, nondominant hand, and both hands simultaneously for children in this study. Mean Visual-Motor Integration (VMI) scores for children with low-risk and high-risk ALL decreased from the first evaluation to year 1 and again at year 2. Mean VMI scores for children with standard risk ALL increased from the first evaluation to year 1 and then decreased at year 2. Significant positive correlations were found between the Purdue and the VMI at both year 1 and year 2, suggesting that the Pegboard performance consistently predicts the later decline in visual-motor integration. Significant correlations were found between the Purdue Pegboard at baseline and the Performance IQ during year 1, though less consistently during year 2. A similar pattern was also observed between the baseline Pegboard performance and performance on the Coding and Symbol Search subtests during year 1 and year 2., Conclusions: In this study, children with ALL experienced significant and persistent visual-motor problems throughout therapy. These problems continued during the first and second years of treatment. These basic processing skills are necessary to the development of higher-level cognitive abilities, including nonverbal intelligence and academic achievement, particularly in arithmetic and written language.

A method of processing accidental coincidence events (AC) and detector efficiency (DE) calibration data, which reduces the statistical noise in these measurements, and, consequently, reduces the noise in positron emission tomographic images using the technique, is described. The technique uses the fact that, in these measurements with N detectors in coincidence with N other detectors, N2 values of ACs or DEs are measured. However, these values are composed of only 2N components, which are either singles rates or individual DEs. The full set of data is used to implicitly solve for these values and the individual ACs or DEs recalculated with an improvement in statistical error equivalent to an N2/(2N + 1) increase in accumulated events for the case of a uniform distribution. This result was verified experimentally.