Neuropsychological assessment for management of patients with deep brain stimulation

Abstract

The inclusion of cognitive and behavioural criteria has been recommended for the management of patients with deep brain stimulation. A neuropsychological assessment may contribute to different issues: (1) selection of the best candidates for surgery, (2) evaluation of the consequences of surgery, (3) research of the best electrode implantation. Recent neuropsychological studies indicate that (1) with appropriate inclusion criteria, the effects of surgery on cognitive functions are limited; (2) an aggravation of behavioural disorders might be related to subthalamic nucleus (STN) stimulation and depend on electrode location; (3) subthalamic nucleus stimulation, but not the internal globus pallidus stimulation, improves psychomotor efficiency and working memory. These results would suggest that the implanted electrodes are not solely targeting the motor circuit and that the cognitive and motor circuits are not completely segregated.

Rivastigmine for the treatment of dementia associated with Parkinson’s disease

“…Forty-eight percent of these survivors fulfi lled criteria for dementia (Hely et al 2005). Consistent with these fi ndings, most PD patients undergoing neuropsychological testing to exclude dementia before deep brain stimulation surgery display some level of cognitive dysfunction (typically executive dysfunction) (Saint-Cyr et al 2000;Pillon 2002). Cognitive decline is therefore perhaps a ubiquitous feature as PD progresses.…”

“…If you examine various neuropsychological testing batteries recommended for evaluation of cognitive function in PD, you will fi nd a hodge-podge of cognitive scales and tests with many lacking widespread use and validation in PD (Defer et al 1999;Saint-Cyr et al 2000;Pillon et al 2002;Burn et al 2006;Voon et al 2006). Emre et al (2004), Giladi et al (2003), Fogelson et al (2003), and Reading et al (2002) used cognitive scales that were assessed and validated in AD (ADCS-GCIS, ADCS-ADL, NPI) without signifi cant validation in PDD.…”

“…The incidence and prevalence of PDD depends upon the neuropsychological tests and the criteria used to defi ne PDD and neuropsychological testing batteries can vary considerably from center to center (Defer et al 1999;Saint-Cyr and Trepanier 2000;Pillon 2002;Burn et al 2006;Voon et al 2006).…”

Neuropsychological Considerations for Parkinson’s Disease Patients Being Considered for Surgical Intervention with Deep Brain Stimulation

“…In an effort to design a short (90 min) battery that could be used to exclude atypical PD candidates from undergoing DBS, Pillon [ 85 ] suggested that neuropsychologists administer the Mattis Dementia Rating Scale [ 87 ] as an estimate of global cognitive functioning, the Grober and Buschke test [ 88 ] to investigate verbal memory, the Boston Naming Test (BNT; [ 89 ] ), an apraxia examination [ 90 ] , and the Rey-Osterrieth Complex Figure Copying (RCFT; [ 91 ] ) to assess "instrumental functions." The author also recommends conducting a neuropsychiatric interview and administering the Montgomery and Asberg Depression Rating Scale (MADRS; [ 92 ] ); the latter was speci fi cally selected because it is sensitive to changes in depressive symptoms over time [ 85 ] .…”

“…Given the varying cognitive, affective, and behavioral pro fi les of people diagnosed with PD, as well as the neurocognitive changes that have been reported in patients who have undergone DBS surgery, neuropsychological assessments have become an essential component of pre-DBS screening protocols at many medical centers [ 85 ] . The goal of such an evaluation is to aid in excluding patients who have Parkinson's plus syndromes (e.g., multiple systems atrophy, progressive supranuclear palsy, corticobasal degeneration) and are therefore not expected to bene fi t from surgery [ 86 ] , as well as patients with preexisting cognitive deterioration or behavioral disorders that place them at increased risk for the exacerbation of their cognitive dif fi culties if they were to undergo DBS surgery [ 20,55 ].…”