Engelien Lannoo

Cognitive outcome after unilateral pallidal stimulation in Parkinson’s disease

OBJECTIVES Chronic high frequency electrostimulation of the globus pallidus internus mimics pallidotomy and improves clinical symptoms in Parkinson’s disease. The aim of this study was to investigate the cognitive consequences of unilateral deep brain stimulation. METHODS Twenty non-demented patients with Parkinson’s disease (age range 38–70 years) were neuropsychologically assessed 2 months before and 3 months after unilateral pallidal stimulation. The cognitive assessment included measures of memory, spatial behaviour, and executive and psychomotor function. In addition to group analysis of cognitive change, a cognitive impairment index (CII) was calculated for each individual patient representing the percentage of cognitive measures that fell more than 1 SD below the mean of a corresponding normative sample. RESULTS Neurological assessment with the Hoehn and Yahr scale and the unified Parkinson’s disease rating scale disclosed a significant postoperative reduction in average clinical Parkinson’s disease symptomatology (p<0.001). Repeated measures multivariate analysis of variance (using right/left side of stimulation as a between subjects factor) showed no significant postoperative change in cognitive performance for the total patient group (main effect of operation). The side of stimulation did not show a significant differential effect on cognitive performance (main effect of lateralisation). There was no significant operation by lateralisation interaction effect. Although the patients experienced significant motor symptom relief after pallidal stimulation, they remained mildly depressed after surgery. Analysis of the individual CII changes showed a postoperative cognitive decline in 30% of the patients. These patients were significantly older and took higher preoperative doses of levodopa than patients showing no change or a postoperative cognitive improvement. CONCLUSIONS Left or right pallidal stimulation for the relief of motor symptoms in Parkinson’s disease seems relatively safe, although older patients and patients needing high preoperative doses of levodopa seem to be more vulnerable for cognitive decline after deep brain stimulation.

Course of neuropsychological recovery from moderate-to-severe head injury: a 2-year follow-up

Neuropsychological outcome and recovery of a group of 91 patients with moderate-to-severe head injuries were prospectively investigated over a 2 year period, with evaluations at acute hospital discharge at 6 months and 2 years post-injury. A group of 39 trauma patients with injuries to parts of the body other than the head were used as controls. The head injured group performed significantly worse than the control group at baseline, 6 months and 2 years post-injury. Significant improvement was found during the first 6 months, but also between 6 months and 2 years post-injury. Trauma controls also performed significantly better at 6 months post-injury compared to baseline. Differential practice effects between groups cause difficulties in determining recovery. Within the head injured group, three distinct recovery groups were identified varying as a function of coma-length and coma-duration. The first group is comparable with the trauma controls. The other two groups demonstrate significant neuropsychological impairments at baseline, with one group showing a marked improvement over the 2 year period, and the other group showing only small improvement over this time period.

Changes in quality of life following unilateral pallidal stimulation in parkinson’s disease

Twenty patients with Parkinsons disease (age range 38-70 years) completed the Sickness Impact Profile (SIP) 2 months before and 3 months after long-term high-frequency electrostimulation of the globus pallidus internus to improve clinical symptoms. The SIP provides an estimate of perceived quality of life on 12 health-status categories. Neurological assessment with the Hoehn and Yahr scale and the Unified Parkinsons Disease Rating Scale revealed a significant postoperative reduction in clinical symptomatology (p<0.001). The patients experienced a general improvement in self-reported quality of life that exceeded the purely motor and physical aspects of quality of life. The significant postoperative drop in perceived impairment of communication skills can be considered the most important subjective improvement. Longitudinal research on a larger sample of patients is necessary to evaluate the durability of the subjective improvement in quality of life after unilateral pallidal stimulation.

Cognitive Neuroactivation Using SPECT and the Stroop Colored Word Test in Patients with Diffuse Brain Injury

Psychomotor slowing in patients with diffuse brain injury frequently underlies impaired cognitive performance on neuropsychological tests, for example, the Stroop Colored Word test. The aim of the present study was to determine the neural basis associated with performance on the Stroop interference subtask in patients with diffuse brain injury. We hypothesized that patients would be slower than healthy controls, and that this would be associated with brain activations other than those seen in healthy subjects. Brain perfusion, using a split-dose activation paradigm with single photon emission tomography (SPECT) and the Stroop test, was assessed in 9 patients with diffuse brain injury. The Stroop interference score was calculated as a behavioral parameter, and functional imaging data were analyzed with statistical parametrical mapping (SPM99) to determine significant voxel-wise differences of activation between the control and the activation condition. Patients were impaired on the interference subtask of the Stroop test. Comparison of the SPECT data obtained during the activation condition with those obtained during the control condition by means of SPM showed significant activations in the left inferior parietal lobe, the right anterior cingulate extending into the right middle frontal gyrus and the right caudate, and the left posterior cingulate cortex. Patients with diffuse brain injury were slower than healthy controls on the interference subtask of the Stroop test, suggesting difficulty with resistance to distractions. This finding was associated with activation effects in posterior (mainly parietal) brain areas in addition with activation of previously observed anterior (mainly anterior cingulate) brain regions.

Epidemiology of acquired brain injury (ABI) in adults: prevalence of long-term disabilities and the resulting needs for ongoing care in the region of Flanders, Belgium

In order to plan services for long-term care of those with acquired brain injury (ABI), the prevalence of ABI was investigated by using a postal inquiry sent to a representative sample of general practitioners, of whom 121 cooperated and registered 186 cases. The corresponding estimated prevalence of adults with ABI-related disabilities is 183 per 100 000 population. The large majority remained at home without professional assistance. One in five had resumed education or regained full employment, but over half spent their day at home with no specific activity. The need for specific care at home was present in almost half of the patients. One-quarter had employment-related needs, and one in five had living needs for specialized accommodation or supported living. In conclusion, this study primarily revealed unfulfilled needs in the area of day services aiming at a maximal social and professional reintegration.

Cerebral perfusion pressure and intracranial pressure in relation to neuropsychological outcome

AbstractObjective: The study attempted to examine the relationship between neuropsychological functioning and reduced cerebral perfusion pressure (CPP), raised intracranial pressure (ICP), and reduced mean arterial pressure (MAP), monitored during intensive care treatment. Design: This prospective follow-up study included consecutive patients and evaluated outcome at 6 months postinjury by the administration of a neuropsychological test battery. Setting: The study was conducted at the University Hospital of Gent, Belgium. Patients and participants: Over a 30-month period, 43 patients were included. Inclusion criteria were the following: hospital admission following closed head injury, ICP monitoring, no medical history of central nervous system disease or mental retardation, survival for at least 6 months, and informed consent for participation. Interventions: All patients received the hospital’s standard treatment for head injury, which remained unchanged during the study period. Measurements and results: Reduced CPP was analyzed using the number of observed values below 70 mmHg, raised ICP using the number of values above 20 mmHg, and MAP using the number of values below 80 mmHg. The neuropsychological test battery included 11 measures of attention, information processing, motor reaction time, memory, learning, visuoconstruction, verbal fluency, and mental flexibility. No linear relationships were found between overall neuropsychological impairment and episodes of reduced CPP, raised ICP, or reduced MAP. Conclusions: Although reduced CPP and raised ICP are frequent, often fatal, complications of head injury, in survivors they do not seem to be related to later neuropsychological functioning.

Personality change following head injury: assessment with the NEO Five-Factor Inventory.

We evaluated personality change following head injury in 68 patients at 6 months postinjury using the NEO Five-Factor Inventory to assess the five personality dimensions of the Five-Factor Model of Personality. All items had to be rated twice, once for the preinjury and once for the current status. Twenty-eight trauma patients with injuries to other parts of the body than the head were used as controls. For the head-injured group, 63 relatives also completed the questionnaire. The results showed no differences between the ratings of head-injured patients and the ratings of trauma control patients. Both groups showed significant change in the personality dimensions Neuroticism, Extraversion, and Conscientiousness. Compared to their relatives, head-injured patients report a smaller change in Extraversion and Conscientiousness. Changes were not reported on the Openness and Agreeableness scales, by neither the head-injured or their relatives, nor by the trauma controls.

Neuropsychological aspects of Marfan syndrome

We evaluated the neuropsychological status of 13 adult patients with Marfan syndrome. All subjects were administered the same neuropsychological test battery that included nine measures covering a broad range of cognitive abilities such as attention and concentration, learning and memory, and verbal and non‐verbal abilities. Compared to a control group of 13 normal healthy subjects matched for sex, age and verbal intelligence, Marfan patients only performed significantly worse on tests measuring sustained visual attention and visuoconstruction. Although these tests use visual material and depend on visual perception and processing, the visual acuity problems associated with the syndrome could not explain these differences, nor could the use of beta‐blocking medication or the presence of joint hypermobility. The findings suggest that problems with sustained visual attention and visuoconstruction may be present in Marfan syndrome over and above visual acuity problems and other phenomena associated with the disease. Further research on the neuropsychological aspects of Marfan syndrome is needed, using larger patient groups and more adequate control groups such as non‐affected siblings and matched controls with similar visual impairment.

The Torneo Project for Professional Reintegration of People with Acquired Brain Injury

Although brain injuries often result in permanent unemployment, many survivors remain motivated to work and identify it as a primary rehabilitation goal. The European Torneo project offered the opportunity to realise a specialised training program for professional rehabilitation of brain injured people who are functionally independent in activities of daily living and want to return to work or school.