Pramod Kr. Pal

Prevalence and profile of Restless Legs Syndrome in Parkinson's disease and other neurodegenerative disorders: A case-control study

BACKGROUND Restless Legs Syndrome (RLS) is associated with impaired central dopaminergic neurotransmission. Though a link between RLS and parkinsonism has been proposed, the prevalence of RLS in parkinsonian disorders is poorly documented. OBJECTIVE To determine the prevalence of RLS in patients with Parkinsons Disease (PD), Progressive Supranuclear Palsy (PSP), Multiple System Atrophy (MSA) and Dementia with Lewy Bodies (DLB). METHODS We evaluated 187 consecutive patients with parkinsonian disorders (PD = 134, PSP = 27, MSA = 21, DLB = 5) and 172 healthy controls. RLS was diagnosed using the International RLS Study Group (IRLSSG) criteria and the severity of RLS was assessed in patients with definite RLS. Quality of sleep was evaluated with established scales. RESULTS The prevalence of RLS was higher in patients compared to controls (9.6% vs. 2.9%; p = 0.009) and was highest in PD (11.9%). RLS was present in only one patient each with MSA and PSP and none with DLB. The mean IRLSSG severity score of patients was 16.2 ± 6.5. The global Pittsburgh Sleep Quality Index score and Epworth Sleepiness Scale score were significantly higher in patients compared to controls (p < 0.001). PD patients with RLS had lower Parkinsons Disease Sleep Scale (PDSS) score compared to patients without RLS (p = 0.023). There was no significant difference in gender, age, duration and severity of PD between the two groups. CONCLUSIONS Our study found a higher prevalence of RLS in PD compared to healthy controls or other parkinsonian disorders. Apart from PDSS score, there was no significant difference in the clinical characteristics of PD patients with and without RLS.

Association between cortical volume loss and cognitive impairments in essential tremor

Impairment of cognitive functions occurs in essential tremor (ET) although the mechanism is largely unknown. A possible association between cognitive performance and brain atrophy in ET patients was examined using neuropsychological tests and voxel‐based morphometry (VBM).

Understanding the pathophysiology of essential tremor through advanced neuroimaging: A review

Essential tremor (ET) is one of the most common neurological diseases; but aetio-pathogenesis of ET is largely unknown. Major advances in neuroimaging may help us understand the mechanisms and networks involved in ET. Most commonly employed techniques include functional and structural neuroimaging. Functional imaging studies suggest that tremors in ET are of central origin with role of olivo-cerebellar and cerebello-thalamo-cortical pathways in tremor generation. Apart from tremors, ET is also characterised by cognitive dysfunction. Functional magnetic resonance imaging (fMRI) studies suggest the role of cerebellum posterior lobules, dorsolateral prefrontal cortex and parietal lobules in cognitive impairment in ET. Positron emission tomography studies indicate the role of gamma-aminobutyric-acid dysfunction in tremor generation while most of the structural imaging studies (diffusion tensor imaging, voxel based morphometry, T2*-relaxometry on magnetic resonance imaging) along with magnetic resonance spectroscopic imaging point toward neurodegeneration. This review focuses on recent findings in the field of imaging in ET which may help understand the disease pathogenesis and mechanisms.

Rapid eye movement sleep behaviour disorder in young- and older-onset Parkinson disease: a questionnaire-based study

BACKGROUND Rapid eye movement sleep behavior disorder (RBD) is common in Parkinson disease (PD). OBJECTIVES To determine the frequency of clinically probable RBD (cpRBD) in young-onset (21 to < or =40 years; YOPD) and older-onset PD (>40 years; OOPD) and characterize its pattern. METHODS A total of 156 patients with PD (YOPD-51, OOPD-105) were clinically examined and the presence of RBD was diagnosed using the minimal criteria for diagnosis of RBD (International Classification of Sleep Disorders, ICSD-1). RBD screening questionnaire based on the minimal criteria was used. The bed-partners were also interviewed with Mayo sleep questionnaire. Other scales included Unified Parkinson Disease Rating Scale part III (UPDRS III), Hoehn & Yahr stage, Mini Mental Status Examination, Pittsburgh Sleep Quality Index, Parkinson Disease Sleep Scale, Epworth Sleep Scale, Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale. RESULTS cpRBD was diagnosed in 30 (19.2%) patients, majority being OOPD rather than YOPD (86.7% vs. 13.3%; P=0.01). The frequency of RBD was significantly higher (P=0.016) in OOPD (24.8%) compared to those with YOPD (7.8%). Most often (72.4%) RBD occurred after the onset of parkinsonian symptoms. RBD was independently associated with higher global PSQI scores, total ESS scores and total PDSS scores after adjusting for the effects of age, gender, Hoehn & Yahr stage and duration of illness. CONCLUSIONS Patients with RBD were older with later-onset motor symptoms, a more advanced stage, poorer sleep quality, and more frequent daytime sleepiness. Older-onset PD had a higher frequency of RBD than young-onset PD.

Subcortical structures in progressive supranuclear palsy: vertex-based analysis

To study the abnormalities of deep grey matter (GM) structures in patients with progressive supranuclear palsy (PSP) using MR volumetry and shape analysis techniques.

Repetitive transcranial magnetic stimulation induced modulations of resting state motor connectivity in writer's cramp.

Writers cramp (WC) is a focal task‐specific dystonia of the hand which is increasingly being accepted as a network disorder. Non‐invasive cortical stimulation using repetitive transcranial magnetic stimulation (rTMS) has produced therapeutic benefits in some of these patients. This study aimed to visualize the motor network abnormalities in WC and also its rTMS induced modulations using resting state functional magnetic resonance imaging (rsfMRI).

Evaluation of the motor cortical excitability changes after ischemic stroke

Background: We evaluated progressive changes in excitability of motor cortex following ischemic stroke using Transcranial Magnetic Stimulation (TMS). Materials and Methods: Thirty-one patients (24 men, 7 women; age 37.3 ± 8.2 years) were recruited and TMS was performed using Magstim 200 stimulator and a figure-of-eight coil. Resting motor threshold (RMT) was recorded from affected and unaffected hemispheres and motor evoked potential (MEP) was recorded from contralateral FDI muscle. Central motor conduction time (CMCT) was calculated using F wave method. All measurements were done at baseline (2nd), 4th, and 6th week of stroke. Results: Affected hemisphere: MEP was recordable in 3 patients at baseline (all had prolonged CMCT). At 4 weeks, MEP was recordable in one additional patient and CMCT remained prolonged. At 6 weeks, CMCT normalized in one patient. RMT was recordable (increased) in 3 patients at baseline, in one additional patient at 4 weeks, and reduced marginally in these patients at 6 weeks. Unaffected hemisphere: MEP was recordable in all patients at baseline, and reduced significantly over time (2nd week 43.52 ± 9.60, 4th week 38.84 ± 7.83, and 6th week 36.85 ± 7.27; P < 0.001). The CMCT was normal and remained unchanged over time. Conclusion: The increase in excitability of the unaffected motor cortex suggests plasticity in the post-stroke phase.

Quality of sleep in young onset Parkinson's disease: Any difference from older onset Parkinson's disease.

BACKGROUND Sleep disorders occur commonly in Parkinsons disease and are often under-recognized and under treated in clinical practice. OBJECTIVES To determine the quality of sleep in patients with Young onset Parkinsons disease (YOPD) and to note whether there is any difference in quality of sleep from those patients with older onset Parkinsons disease (OOPD). METHODS One hundred and fifty six patients with Parkinsons disease (YOPD-51, OOPD-105) were clinically examined and quality of sleep was determined using Pittsburgh sleep quality index (PSQI), Parkinsons disease Sleep Scale (PDSS) and Epworth Sleep Scale (ESS). Other scales included Unified Parkinsons Disease Rating Scale -part III (UPDRS-III), Hoehn & Yahr Stage, Mini Mental Status Examination, Hamilton anxiety rating scale and Hamilton depression rating scale. RESULTS The frequency of insomnia was higher in OOPD (55.2%) as compared to YOPD (27.5%) group (p = 0.001). The frequency of nightmares was lower in YOPD (7.8%) when compared to OOPD (24.8%) group (p = 0.012). The mean hours of actual sleep per night were higher in YOPD patients. Global PSQI score was better in YOPD indicating good overall sleep quality in YOPD patients. The total ESS score was significantly lower in YOPD (p = 0.019). The total PDSS score was significantly better in YOPD patients (p = 0.018). CONCLUSIONS Patients with YOPD had an overall better quality of sleep with lesser incidence of insomnia, nightmares, daytime sleepiness and restlessness during sleep.

Rapid eye movement sleep behaviour disorder in women with Parkinson's disease is an underdiagnosed entity.

Rapid eye movement sleep behavior disorder (RBD) is common in Parkinsons disease (PD). Little information exists about RBD in women with PD. The aim of this study was to determine the clinical expression of RBD in women with PD and note any differences in women with PD with and without RBD. One hundred fifty-six patients with PD were recruited. There were 37 women with PD and probable RBD was diagnosed using the RBD Screening Questionnaire. Other scales included Pittsburgh Sleep Quality Index, Parkinsons Disease Sleep Scale, Epworth Sleep Scale, Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale. Probable RBD was diagnosed in 10 women with PD (27%). Most often (70%) RBD occurred after the onset of parkinsonian symptoms. Women with probable RBD were older, had shorter duration of PD symptoms, lower tremor score, and higher axial signs score. They had insomnia (80% versus non-probable RBD patients 44%, p=0.019), and poor sleep quality with excessive daytime sleepiness. Anxiety and depression were common in women with probable RBD. Episodes were brief and confined to vocalization and simple limb movements. No injury to self or bed partners was noted. Women with PD have fewer fights and less aggressive dream enacting behaviour than men, but suffer from significant disturbed sleep, and levels of anxiety and depression.

Three‐dimensional neuromelanin‐sensitive magnetic resonance imaging of the substantia nigra in Parkinson's disease

The aim was to investigate the diagnostic utility of signal intensity measurement of the substantia nigra pars compacta (SNc) using three‐dimensional (3D) neuromelanin‐sensitive magnetic resonance imaging (MRI), for discrimination of patients with Parkinsons disease (PD) from healthy controls.