Interventional magnetic resonance imaging-guided subthalamic nucleus deep brain stimulation for Parkinson's disease: Patient selection.

BACKGROUND: Interventional magnetic resonance imaging (iMRI) guided deep brain stimulation (DBS) for Parkinson's disease (PD) has been shown to be effective. The costs of a dedicated intraoperative MRI may be prohibitive. The procedure can also be performed in a diagnostic scanner, however this presents challenges for utilization of time when the scanner is used both as a diagnostic and an interventional unit. This report outlines our novel methodology for patient selection for implantation in a diagnostic MR scanner, as an attempt to streamline the use of resources. A retrospective review of our outcomes is also presented. METHODS: DBS candidacy evaluation included a PD questionnaire-39. Anxiety, age, difficulties in communication and body habitus were factors that were assessed in selecting patients for this technique. Eleven patients underwent iMRI-guided DBS implantation in the subthalamic nucleus. All patients were implanted bilaterally. Unified PD rating scale (UPDRS) part III and L-dopa dose were compared pre- and post-stimulation. A cohort of 11 DBS patients not selected for iMRI-guided DBS were also reported for comparison. RESULTS: For the iMRI-guided patients, mean "Off" UPDRS III score was 47.6 (standard deviation [SD] 8.26). Postoperative "On" medication, "On" stimulation UPDRS III was 13.6 (SD 5.23). Mean preoperative L-dopa dose was 1060 mg (SD 474.3) and mean postoperative L-dopa dose was 320 (SD 298.3). CONCLUSION: iMRI-guided DBS is a newly emerging technique for surgical treatment of patients with PD. We present a novel scoring system for patient selection assessing anxiety, age, ability to communicate, and body habitus to identify patients who will be benefited most from this technique.

Brief report: Television viewing and risk for attention problems in preschool children.

OBJECTIVES: This study examined whether high levels of television viewing are associated with attention problems and hyperactivity in preschool children. METHODS: Parent and teacher ratings of inattention, hyperactivity and impulsivity, objectively measured activity level, and parental estimation of early television exposure were collected for a sample of preschool children. Separate linear regression analyses were conducted with parent and teacher behavioral ratings and objectively assessed activity level as outcome variables. RESULTS: Results indicated that after controlling for demographic factors (i.e., age, sex, and SES), television exposure accounted for a significant proportion of the variance in teacher ratings of inattentive/hyperactive behaviors, as well as objectively measured activity level. CONCLUSIONS: These findings partially replicate those from a recent, highly publicized study indicating a correlation between television exposure and attention-deficit/hyperactivity disorder (ADHD)-associated behaviors. However, it remains unclear as to whether elevated levels of television viewing are the cause or result of ADHD symptoms.

Sustained attention and response inhibition in young children at risk for Attention Deficit/Hyperactivity Disorder.

BACKGROUND: Studies of school-aged children, adolescents, and adults with Attention Deficit/Hyperactivity Disorder (ADHD) have variably shown ADHD-related impairment in both inhibitory control and sustained attention. However, few studies have examined ADHD-associated patterns of performance on these tasks among younger children (below age 7 years). METHODS: A combined continuous performance test and go/no-go task (CPT/GNG) and the Day-Night Stroop Task (DNST) were administered to an ethnically diverse sample of 3.44- to 6.95-year-old children rated by parents and teachers as being either high risk or low risk for ADHD. All children performed the DNST (N = 71) and a subset of the sample (N = 44) performed the CPT/GNG. Analyses assessed task validity as well as the effects of age and risk status. RESULTS: Significant main effects for age and risk status were found on all tasks. In addition, age x condition interactions were found for the CPT and DNST, which suggest that the tasks were sensitive to age-related changes in sustained attention and inhibitory control respectively. No significant risk status x condition interactions were found, suggesting that young children at risk for ADHD do not exhibit specific deficits in either inhibitory control or sustained attention. The most consistent effect related to risk status across tasks was the greater number of errors and longer and more variable reaction times on the part of children at risk for ADHD irrespective of condition. CONCLUSIONS: ADHD-associated decrements in performance on these tasks appear to be attributable either to generalized behavioral dysregulation or poor state regulation rather than to deficient inhibitory control.

Neuropsychological correlates of ADHD symptoms in preschoolers.

The authors examined the neuropsychological status of 22 preschoolers at risk for attention-deficit/hyperactivity disorder (ADHD) and 50 matched control children, using measures of nonverbal working memory, perceptual and motor inhibition, and memory for relative time. All tasks included paired control conditions, which allowed for the isolation of discrete executive function constructs. Group differences were evident on several measures of neuropsychological functioning; however, after accounting for nonexecutive abilities, no deficits could be attributed to specific functions targeted by the tasks. Performance on executive measures was not related to objective indices of activity level or ratings of ADHD symptoms. Yet, the fact that at-risk preschoolers were highly symptomatic casts doubt on whether executive function deficits and/or frontostriatal networks contribute etiologically to early behavioral manifestations of ADHD.

Self-report and objective measures of ADHD-related behaviors in parents of preschool children at risk for ADHD.

OBJECTIVE: Few studies have used a combination of objective and self-report measures to examine neuropsychological and behavioral functioning in parents of children with attention-deficit/hyperactivity disorder (ADHD). This study examined attention and inhibitory control in the parents of preschool children who were rated as "at risk" for developing ADHD as compared with parents of controls. METHODS: Preschool children (N=53) were divided into at risk for ADHD and control groups based on parent and teacher ratings of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition ADHD symptoms. One parent of each child was administered an identical pairs Continuous Performance Test (CPT-IP), a Go/No-Go task, and the Brown Attention-Deficit Disorder Scale for Adults. RESULTS: Parents of preschoolers at risk for ADHD showed a pattern of responding on measures of vigilance characterized by slower reaction times and increased commission errors as compared with parents of controls. There were no significant group differences on self-report measures on the Brown Attention-Deficit Disorder Scale for Adults. CONCLUSION: Parents of preschoolers at risk for ADHD appear to exhibit cognitive processing deficits that may not be evident using self-report measures. Further research is needed to more clearly identify the specific nature of these neuropsychological deficits and to determine whether they have a negative impact on their children.