Robert Iansek

Background: Tablet formulations of Parkinson’s disease (PD) medications may become ineffective at managing motor fluctuations in advanced PD. The liquid formulation, levodopa carbidopa ascorbic acid solution, or LCAS, is an effective and inexpensive treatment for motor fluctuations however it remains underutilized. Objective: We compared the efficacy of LCAS with tablet formulations and Duodopa jejunal infusion through routine inpatient management using hourly functional status measures, the Timed Up and Go Test (TUG). The TUG differentiates between ‘off’ and ‘on’ states and quantifies motor fluctuations. Methods: Experienced nurses used the TUG times and functional observations recorded hourly throughout the waking day to optimize the LCAS hourly dose and the Duodopa flow rate over several days. When patients were stabilized on each of the interventions, the TUG measures were then recorded to compare the outcomes of the interventions. Results: Twenty-six participants had TUG times ...

Huntington's disease patients perform automatic movements in a bradykinetic manner, somewhat similar to patients with Parkinson's disease. Cortical activity relating to the preparation of movement in Parkinson's disease is significantly improved when a cognitive strategy is used. It is unknown whether patients with Huntington's disease can utilise an attentional strategy, and what effect this strategy would have on the premovement cortical activity. Movement-related potentials were recorded from 12 Huntington's disease patients and controls performing externally cued finger tapping movement, allowing an examination of cortical activity related to movement performance and bradykinesia in this disease. All subjects were tested in two conditions, which differed only by the presence or absence of the cognitive strategy. The Huntington's disease group, unlike controls, did not produce a rising premovement potential in the absence of the strategy. The Huntington's disease group did produce a rising premovement potential for the strategy condition, but the early slope of the potential was significantly reduced compared with the control group's early slope. These results are similar to those found previously with Parkinson's disease patients. The strategy may have put the task, which previously might have been under deficient automatic control, under attentional control.

Autism and Asperger's disorder (AD) are characterised by impairments in social interaction, stereotypic behaviours or restricted interests. Although currently listed as distinct clinical disorders, the validity of their distinction remains controversial. This study examined gait in children with autism and AD. Eleven children with high-functioning autism and eleven children with AD completed a series of walking tasks. Results indicated distinct movement disturbance; these findings are discussed in light of seminal papers in this field by Vilensky et al. (Arch Neurol 38:646-649, 1981) and Hallett et al. (Arch Neurol 50:1304-1308, 1993) who interpret the gait of individuals with autism using parkinsonian and cerebellar-ataxia patient models, respectively. Distinctions in gait patterns implicating perhaps unique motor circuit disturbances support the hypothesis that autism and AD may have unique neurodevelopmental trajectories.

Movement-related potentials (MRPs) reflect increasing cortical activity related to the preparation and execution of voluntary movement. Execution and preparatory components may be separated by comparing MRPs recorded from actual and imagined movement. Imagined movement initiates preparatory processes, but not motor execution activity. MRPs are maximal over the supplementary motor area (SMA), an area of the cortex involved in the planning and preparation of movement. The SMA receives input from the basal ganglia, which are affected in Huntington's disease (HD), a hyperkinetic movement disorder. In order to further elucidate the effects of the disorder upon the cortical activity relating to movement, MRPs were recorded from ten HD patients, and ten age-matched controls, whilst they performed and imagined performing a sequential button-pressing task. HD patients produced MRPs of significantly reduced size both for performed and imagined movement. The component relating to movement execution was obtained by subtracting the MRP for imagined movement from the MRP for performed movement, and was found to be normal in HD. The movement preparation component was found by subtracting the MRP found for a control condition of watching the visual cues from the MRP for imagined movement. This preparation component in HD was reduced in early slope, peak amplitude, and post-peak slope. This study therefore reported abnormal MRPs in HD, particularly in terms of the components relating to movement preparation, and this finding may further explain the movement deficits reported in the disease.

Gait abnormalities have been widely reported in individuals with autism and Asperger's disorder. There is controversy as to whether the cerebellum or the basal-ganglia frontostriatal regions underpin these abnormalities. This is the first direct comparison of gait and upper-body postural features in autism and Asperger's disorder. Clinical and control groups were matched according to age, height, weight, performance, and full scale IQ. Consistent with Hallet's (1993) cerebellar-gait hypothesis, the autistic group showed significantly increased stride-length variability in their gait in comparison to control and Asperger's disorder participants. No quantitative gait deficits were found for the Asperger's disorder group. In support of Damasio and Maurer's (1982) basal-ganglia frontostriatal-gait hypothesis, both clinical groups were rated as showing abnormal arm posturing, however, only the Asperger's group were rated as significantly different from controls in terms of head and trunk posturing. While DSM-IV-TR suggests that Asperger's disorder, but not autism, is associated with motoric clumsiness, our data suggest that both clinical groups are uncoordinated and lacking in motor smoothness. Gait differences in autism and Asperger's disorder were suggested to reflect differential involvement of the cerebellum, with commonalities reflecting similar involvement of the basal-ganglia frontostriatal region.

Autism and Asperger's disorder (AD) are neurodevelopmental conditions that affect cognitive and social-communicative function. Using a movement-related potential (MRP) paradigm, we investigated the clinical and neurobiological issue of 'disorder separateness' versus 'disorder variance' in autism and AD. This paradigm has been used to assess basal ganglia/supplementary motor functioning in Parkinson's disease. Three groups (high functioning autism [HFA]: 16 males, 1 female; mean age 12y 5mo [SD 4y 4mo]; AD: 11 males, 2 females; mean age 13y 5mo [SD 3y 8mo]; comparison group: 13 males, 8 females; mean age 13y 10mo [SD 3y 11mo]) completed a cued motor task during electroencephalogram recording of MRPs. The HFA group showed reduced peak amplitude at Cz, indicating less activity over the supplementary motor area during movement preparation. Although an overall significant between-group effect was found for early slope and peak amplitude, sub-analysis revealed that the group with AD did not differ significantly from either group. However, it is suggested that autism and AD may be dissociated on the basis of brain-behaviour correlations of IQ with specific neurobiological measures. The overlap between MRP traces for autism and Parkinson's disease suggests that the neurobiological wiring of motor functioning in autism may bypass the supplementary motor area/primary motor cortex pathway.

Background. Parkinson disease (PD) is a costly chronic condition in terms of managing both motor and nonmotor symptoms. The burden of disease is high for individuals, caregivers, and the health system. The aim of this study is to estimate the annual cost of PD from the household, health system, and societal perspectives. Methods. A prospective cohort study of newly referred people with PD to a specialist PD clinic in Melbourne, Australia. Participants completed baseline and monthly health resource use questionnaires and Medicare data were collected over 12 months. Results. 87 patients completed the 12-month follow-up assessments. The mean annual cost per person to the health care system was $32,556 AUD. The burden to society was an additional $45,000 per annum per person with PD. The largest component of health system costs were for hospitalisation (69% of total costs). The costs for people with moderate to severe disease were almost 4 times those with mild PD ($63,569 versus $17,53...

Background Despite the finding that Parkinson disease (PD) occurs in more than one in every 1000 people older than 60 years, there have been few attempts to quantify how deficits in impairments, activity, participation, and quality of life progress in this debilitating condition. It is unclear which tools are most appropriate for measuring change over time in PD. Methods and design This protocol describes a prospective analysis of changes in impairments, activity, participation, and quality of life over a 12 month period together with an economic analysis of costs associated with PD. One-hundred participants will be included, provided they have idiopathic PD rated I-IV on the modified Hoehn & Yahr (1967) scale and fulfil the inclusion criteria. The study aims to determine which clinical and economic measures best quantify the natural history and progression of PD in a sample of people receiving services from the Victorian Comprehensive Parkinson's Program, Australia. When the da...

Introduction. There is a higher prevalence of Parkinson’s disease (PD) in rural Australia and a poorer perceived quality of life of rural Australians with PD. Coordinated multidisciplinary teams specialised and experienced in the treatment of PD are recommended as the preferred model of care best able to manage the complexities of this disorder. There remains a lack of team-based specialised PD services in rural Australia available to people living with PD. This study aims to explore how the lack of specialised PD services impacts on the person’s experiences of the health care they receive in rural Victoria. This study compared the health-care experiences of two different cohorts of people with PD living in rural Victoria; one cohort living in East Gippsland have had an established comprehensive care model implemented with local trained teams and supported by a metropolitan PD centre, and the other cohort was recruited from the remainder of Victoria who had received standard rural c...

In Australia 1% of individuals aged over 50 years have Parkinson's disease (PD). Guidance for commencing device-assisted therapies (DATs) for PD in Australia was developed based on a review of European recommendations and their relevance to the local clinical setting. An online survey and teleconference discussions were held by a group of eight local movement disorder experts to develop consensus. Referral to a movement disorder specialist and consideration of DAT is appropriate when motor fluctuations cause disability or reduced quality of life, response to treatment is inconsistent or motor fluctuations and dyskinesias require frequent treatment adjustment without apparent benefit and levodopa is required four or more times daily. Three types of DAT are available in Australia for patients with PD: continuous subcutaneous apomorphine; continuous levodopa-carbidopa intestinal gel infusion; and deep brain stimulation. All improve consistency of motor response. The most important ...

In order to examine the role of the basal ganglia (BG) in the regulation of basic movement parameters, we recorded extracellularly from pallidal neurons in conscious monkeys during the performance of a sequential wrist movement task which was composed of a series of holds and ballistic jumps. The movement sequence was predictable and had to be performed within specified time restraints. We recorded the activity of 297 neurons whose discharges were related to the movement task. We included only neurons whose discharges were related to movements at or about the wrist joint by prior examination outside the behavioural paradigm. Each neuron discharged preferentially to one direction of movement at or about the wrist joint. No consistent correlation was found between neuronal discharge and initial joint position, static load application, amplitude of movement or velocity of movement. The mean onset of neuronal discharge was 2 ms after the onset of EMG activity. The findings implied little contribution from the pallidal neurons in the execution of the current movement or to the movement's parameters. The implications are that the basal ganglia are likely to be concerned with other aspects of movement control.

... Frontal gait apraxia: Pathophysiological mechanisms and rehabilitation. Auteur(s) / Author(s). IANSEK Robert (1 2) ; ISMAIL Noor H. (3) ; BRUCE Margaret (4) ; HUXHAM Frances E. (5) ; MORRIS Meg E. (6) ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). ...

In healthy adults, deficits in identifying a second target following a previously attended target in Rapid Serial Visual Presentation (RSVP) occur between intertarget intervals of approximately 100-500 ms. This Attentional Blink (AB) is investigated in nondemented medicated Parkinson's patients using a modification of the standard paradigm that required the identification of two red letters embedded in a black letter distractor stream. Parkinson's patients and controls produced an equivalent AB, although with a different pattern of errors. Thus, the processing and clearance of information was largely preserved in nondemented Parkinson's patients, without evidence of bradyphrenia. However, perseveration of earlier RSVP items in short-term memory was thought to explain the different pattern of errors.

The allocation of attention to the programming and execution of movement sequences was examined in Parkinson's disease (PD). The time taken to initiate and execute sequences of one, three, and five button taps was examined, while also varying the hand used (left or right) and the attentional resources that could be allocated to sequencing (using single- versus dual-task conditions). These results showed that performance anomalies in PD were most apparent with the preferred right hand under single-rather than dual-task conditions. Subjects suffering from PD may tend to divert attention from the right hand under single-task conditions, and perhaps with short sequences, as well as being less likely to prepare sequences of more than three movements in advance with that hand. These effects were unlikely to reflect asymmetric pathology. If the right hand of such subjects has in some respects now come to behave more like a "clumsy" left hand, this may reflect a deliberate strategic choice in an attempt to cope with a movement impairment.

While older adults typically exhibit slower hesitant movements, this may simply reflect a preference for a cautious movement strategy, rather than any pathological process. To separate strategic preferences from any impairment in the coordination of movement, the present experiment trained older adults to move at the preferred speed of younger adults (and vice versa) in a simple zigzag drawing task on a digitizing tablet which sampled pen position at 200 Hz. Twelve older adults (mean age 69 yrs 8 mo) and 12 young adults (mean age 21 yrs) joined 9 targets 125 mm apart, of either 5, 10 or 20 mm diameter. Once the age groups were matched for movement duration, movement kinematics were examined to determine whether there were differences in the quality or accuracy of their movements. When strategic differences are controlled for, older adults performed the task with comparable overall accuracy, but exhibited greater hesitancy and more submovements. The results suggest a decline in motor coordination rather than any simple strategic preference for caution in movement. The hesitancy of movement to some extent parallels that seen in Parkinson's disease.

The basal ganglia (BG) may play a part in motor sequencing. Individuals with Parkinson's disease (PD) may exhibit progressive slowing (sequence effect) during motor sequences such as writing (micrographia) and gait. In the present study, a serial two-way choice reaction time (CRT) task was employed, in which advance information about each next movement was not provided until the participant began moving, thereby assessing the participant's ability to utilize advance information. Participants were 13 individuals with idiopathic PD and 13 age-matched controls. Both PD subjects and controls showed a significant sequence effect in the absence of advance information, possibly reflecting difficulty in initiating and maintaining movement without external cues. PD subjects and controls both exhibited a sequence effect at moderate levels of advance information. At high levels of advance information, PD subjects showed the effect but controls did not, suggesting that controls, unlike PD subjects, were able to use the extra information to facilitate performance, perhaps reflecting more frontal aspects of impairment in PD.

In order to study the role of the basal ganglia (BG) in cognitive aspects of movement, we recorded extracellularly from pallidal neurons in conscious monkeys while they performed a sequential wrist movement task consisting of a series of holds and ballistic jumps. The movement sequence had to be performed within specified time restraints and was predictable. We recorded the activity of 297 neurons whose discharges were related to the movement task. The movement-related response was found to be influenced by the contextual setting and by the degree of difficulty of the task in a subgroup of 82 neurons with a clear response to the first ballistic movement. Predictable and easy movements were usually represented by more prominent movement-related responses in 46% of these neurons; 35% of neurons from a different subset of 105 neurons also demonstrated a second phasic response just before the end of the final hold period of the task. This response was also found to be influenced by the predictability of the final hold period, both in its time duration and also by the direction of the following ballistic movement in double jump tasks. These findings were in keeping with a cognitive role for the BG in movement performance. In particular we suggest that the phasic neuronal activity was an internal cue generated by the BG for predictable movements of a subconscious nature which signals the end of a component of movement in a movement sequence. This cue is appropriately timed to terminate sustained neuronal activity in the SMA and to allow the next movement in the sequence to be executed.

The preparation of individual finger movements was examined in Parkinson's disease (PD), in comparison with a similar study of Huntington's disease (HD). Motor programming was varied by increasing the amount of information available in advance of each movement. PD patients had particular difficulty when there was no cue light in advance of the movement, and when two upcoming movements were cued ahead of the current movement. Such difficulties suggest that PD patients may have difficulty in performing movements without sensory cuing, and in maintaining and organising a future sequence of movements. HD patients had been previously shown to have similar deficits. Commonalities in these once contrasted disorders probably arise from disruption of common mechanisms.

The decision to offer surgery or deep X-ray therapy to patients diagnosed as having malignant gliomas on CT scans is often problematical. Decision-tree analysis is used to make the underlying assumptions explicit in either strategy. Using biopsy and CT data obtained from our own experience, and survival figures from the literature, we are able to demonstrate that the decision is to a large extent related to value judgement. Specifically this relates to the assessment of the utility of long-term survival versus the immediate mortality and morbidity of biopsy in addition to possible difficulties in accepting long-term uncertainty of diagnosis if a biopsy is not performed.

It is a generally held view that intraventricular haemorrhage carries a poor prognosis in cases of intracranial haemorrhage. We tested this view by retrospective analysis of the records of 258 patients who had intracranial blood on CT scans seen over a seven-year period. The mortality and morbidity for intraventricular and non-intraventricular haemorrhage were compared for the three major causes of intracranial bleeding, viz. aneurysm, trauma, and spontaneous intracerebral haemorrhage. No significant difference was found between the two groups for each aetiological category. It was concluded that the CT scan finding of intraventricular blood has no prognostic significance.