Focal hand dystonia, mirror dystonia and motor overflow

Focal hand dystonia (FHD) is a syndrome of sustained muscle contraction, frequently causing twisting and repetitive movements or abnormal postures of the hand. Motor overflow, defined as unintentional muscle contraction that accompanies but is anatomically distinct from the primary dystonic movement, is a frequent but often unrecognized feature of FHD. In this series of eight patients with FHD, we describe two patterns of motor overflow, termed "ipsilateral overflow" and "contralateral overflow", and contrast it with the phenomenon termed "mirror dystonia". These findings extend the phenomenology and provide evidence for widespread abnormalities of motor control in patients with focal hand dystonia.     

Brain magnetic resonance imaging (MRI) in parkinsonian disorders

Magnetic resonance imaging (MRI) is increasingly integrated into neurological diagnostics. In addition to functional MRI, a large number of sequences (T1W, T2W, PD, T2*W gradient echo, diffusion-weighted imaging (DWI), and diffusion tensor imaging (DTI)), investigate CNS abnormalities. Objective quantification techniques (T1W voxel-based morphometry) can also discern subtle anatomical differences. Parkinsonian conditions such as Parkinson's disease, multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration and manganese-induced parkinsonism can clinically overlap, yet have very different prognoses and treatments. Relatively little radiographic interest has focused on movement disorders. Nevertheless in the past decade, a variety of findings, often subtle and routinely overlooked, have emerged to help the clinician differentiate these conditions. This review will summarize and discuss MRI findings in parkinsonian conditions. Most data concern either structural abnormalities or the imaging sequelae of abnormal iron deposition, common in some parkinsonian conditions.     

Dietary Intake and Milk Micronutrient Levels in Lactating Women with Full and Partial Breastfeeding

Background

Micronutrient intake and status in lactating women may impact micronutrient levels in milk.

Objectives

This study aimed to determine the micronutrient intake and status in lactating women, and their association with micronutrient levels in human milk.

Methods

Lactating women were enrolled at 4–6 months postpartum. A 24h food recall was examined and nutrient intakes were analyzed using INMUCAL software. Human milk samples were collected to analyze calcium, copper, iron, and zinc levels. Plasma zinc and serum ferritin levels were determined.

Results

Thirty-four women participated; 19 were classified as full breastfeeding and 15 as partial breastfeeding. Mean levels of calcium, copper, iron, and zinc in human milk were 243, 0.2, 0.2, and 1.56 mg/L, respectively. The prevalence of zinc deficiency (plasma zinc?<?10.7 µmol/L) was 11.8%. No lactating women had iron deficiency. Nutrient intakes were lower than the recommended amounts in 38%–70% of participants, and were not correlated with corresponding nutrient levels in human milk. Multiple linear regression showed significant association between zinc levels in human milk and plasma for lactating women with full breastfeeding (β?=?0.034, 95% confidence interval [0.003, 0.067], p?=?0.040).

Conclusions

Lactating women were at risk of micronutrient deficiency. There was an association between zinc levels in human milk and plasma of lactating women with full breastfeeding. As the nutritional status of lactating women influences the quality of human milk, we should encourage good nutrient intake for lactating women.

     

Magnetic resonance imaging: Implication in acute ischemic stroke management

Multimodality magnetic resonance imaging (MRI) techniques, including diffusion-weighted imaging (DWI), perfusion-weighted imaging (PWI), fluid-attenuated inversion recovery (FLAIR), T2 susceptibility imaging, and magnetic resonance angiography (MRA), quickly provide accurate information about ischemic penumbra (DWI/PWI mismatch), tissue perfusion, and vascular localization in acute stroke setting. These techniques help physicians to select the proper candidates for thrombolysis and/or neuroprotective treatment to salvage tissue at risk (mismatch) and monitor acute stroke patients after treatment. Recent and ongoing trials demonstrate the benefit of treating acute stroke patients depending on tissue at risk of infarction rather than timing of onset. These techniques will extend timing to salvage ischemic brain tissue beyond the 3-hour window. MRI is a powerful tool for managing acute stroke patients and helps elucidate the pathophysiology of cerebral ischemia in a given patient.     

A pilot study: Microlesion effects and tremor outcome in the ventrointermediate deep brain stimulation (VIM-DBS)

Objectives

To perform a pilot study to investigate the relationship between the microlesion effect (MLE) seen in deep brain stimulation (DBS) of the ventralis intermedius nucleus (VIM) and subsequent tremor response and DBS parameter settings.

Patients and methods

Nineteen thalami in 12 patients (11 essential tremor and 1 Parkinson's disease), who underwent unilateral (n = 5) and bilateral VIM-DBS (n = 7) were assessed at pre- and 24-h post-operation, at their initial DBS activation, and at 6-month follow-up. The severity of tremor was rated (from 0 to 4) for each activity including hand at rest, outstretched, wing beating, finger–nose–finger, dot approximation and spiral drawing (total score ranging from 0 to 24). The difference of total tremor score before and 24-h after electrode implants (MLE) was segregated into 3 groups based on immediate (24 h) post-operative tremor improvement: (1) minimal (none or mild, 0–2), (2) moderate (>2–4), and (3) marked (>4). At the initial activation (23.4 ± 3.7 days post-operation), the mean OFF tremor scores were still marginally better in marked than the minimal and moderate MLE groups.

Results

At 6 months, 14 of 19 thalami (74%) were eligible for follow-up analysis. The “OFF” stimulation MLE disappeared in all groups. There was no significant difference of mean ON tremor scores among the groups; however, DBS parameter settings, including amplitude and pulse width, trended to be mildly lower in those with a marked MLE.

Conclusion

MLE has minimal long term clinical effect except for possibly allowing for lower DBS settings.     

Applause sign in parkinsonian disorders and Huntington's disease

The applause sign has been previously reported to be indicative of neurodegenerative disorders, such as progressive supranuclear palsy (PSP). In order to determine the sensitivity, specificity, and positive predictive value, we tested it in patients with PSP, Parkinson's disease (PD), multiple system atrophy (MSA), corticobasal degeneration (CBD), and Huntington's disease (HD). Subjects were asked to clap three times after demonstration by the examiner. The performance was scored as follows: 3 = claps only three times; 2 = claps four times; 1 = claps 5 to 10 times; 0 = claps >10 times. The clap test was videotaped and rated. Patients with CBD, MSA, and PSP showed significant differences in clap scores compared with normal controls. The test differentiated patients with CBD from those with PD (P < 0.005) and HD (P < 0.005), but failed to discriminate patients with PSP from other parkinsonian groups. The specificity of the applause sign is 100% in distinguishing parkinsonian patients from normal subjects with the highest sensitivity in CBD patients. We concluded that the applause sign is highly specific for parkinsonian disorders but it is not a specific sign for PSP; it appears to be most sensitive for CBD. © 2008 Movement Disorder Society     

Effect of Maternal Nutritional Status and Mode of Delivery on Zinc and Iron Stores at Birth

Zinc and iron deficiencies among infants aged under 6 months may be related with nutrient store at birth. This study aimed to investigate the association between zinc and iron stores at birth with maternal nutritional status and intakes during pregnancy. 117 pregnant women were enrolled at the end of second trimester and followed until delivery. Clinical data during pregnancy, including pre-pregnancy body mass index (BMI) and at parturition were collected from medical record. Zinc and iron intakes were estimated from a food frequency questionnaire. Serum zinc and ferritin were determined in maternal blood at enrollment and cord blood. Mean cord blood zinc and ferritin were 10.8 ± 2.6 µmol/L and 176 ± 75.6 µg/L, respectively. Cord blood zinc was associated with pre-pregnancy BMI (adj. ß 0.150; p = 0.023) and serum zinc (adj. ß 0.115; p = 0.023). Cord blood ferritin was associated with pre-pregnancy BMI (adj. ß −5.231; p = 0.009). Cord blood zinc and ferritin were significantly higher among those having vaginal delivery compared to cesarean delivery (adj. ß 1.376; p = 0.007 and 32.959; p = 0.028, respectively). Maternal nutritional status and mode of delivery were significantly associated with zinc and iron stores at birth. Nutrition during preconception and pregnancy should be ensured to build adequate stores of nutrients for infants.     

Tetrabenazine for hyperglycemic-induced hemichorea-hemiballismus.

We reported a 74-year-old woman with new-onset diabetes mellitus who presented with the sudden onset of mild left hemiparesis and marked left hemichorea-hemiballismus. Brain CT scan and MRI showed T1W, T2W, and DWI lesions in the right putamen and caudate, which have been previously reported in cases of hyperglycemic-induced hemichorea-hemiballismus (HIHH). The patient dramatically responded to tetrabenazine within a day. Subsequent dose reductions lead to a reemergence of symptoms. Tetrabenazine improves a variety of hyperkinetic movement disorders but, to our knowledge, its use has never been reported for HIHH.     

Zinc and iron adequacy and relative importance of zinc/iron storage and intakes among breastfed infants

Neonatal nutrient storage and supplies from breast milk contribute to nutrient status and growth of infants during their early life. This study investigated the adequacy of zinc and iron intakes among breastfed infants during the first 4 months and determined the relative importance of zinc/iron storage versus nutrient intakes with infant's biochemical status and growth. A longitudinal study followed lactating women and their breastfed infants from birth to 4 months postpartum. Cord zinc and ferritin concentrations, as indicators of nutrient storages, were determined. Zinc and iron intakes from breast milk were determined by measurement of breast milk volume together with milk zinc and iron concentrations at 2 and 4 months postpartum. Inadequacy of nutrient intakes was determined using average requirement (AR) which were 1.6 and 0.24 mg/day for zinc and iron respectively. Infant's serum zinc and ferritin were determined at 4 months of age. The data were collected from 64 and 56 participants at 2 months and 4 months postpartum. Inadequate zinc intake was found in 14.5 and 40% of infants at 2 and 4 months old, respectively. The prevalence of biochemical zinc and iron deficiency in infants were 76 and 11%, respectively. Iron endowment was significantly associated with serum ferritin at 4 months. The cumulative zinc intake was positively associated with weight gain and weight-for-length Z-score, but not length. This study provides quantitative data on zinc and iron intakes, and demonstrates the relative importance of nutrient storage versus intakes on biochemical status and growth of breastfed infants.     

Motor overflow and mirror dystonia

Motor overflow is an unintentional muscle contraction which accompanies, but is anatomically distinct from the primary dystonic movement. This phenomenological nosology has not been systematically studied in focal hand dystonia (FHD). We conducted a prospective, case-control study to characterize motor overflow and mirror dystonia in patients with FHD. We compared the performance of 30 patients with FHD and 40 healthy controls on a variety of motor tasks, such as writing, drawing a spiral, straight line and a sine wave, repetitive wrist flexion–extension, finger tapping, hand grasping, hand pronation–supination, and a finger-to-nose task with each hand. The assessments were videotaped, the edited video segments were randomized, and an independent investigator who was “blind” to the subject's diagnosis rated the ipsilateral and contralateral overflow and mirror dystonia twice, 6 months apart. Using the mean of the two ratings, ipsilateral overflow was identified in 8.5 ± 2.1 (28%) patients and in 1.5 ± 0.7 (4%) controls (p < 0.001), contralateral overflow in 2.5 ± 0.7 (8%) patients and in 1.5 ± 0.7 (4%) of controls (p = 0.138), and mirror movement in 20.0 ± 0.0 (67%) of patients and in 15.5 ± 4.9 (39%) of controls (p = 0.001). There was a statistically significant correlation of dystonia and overflow score (Pearson's r 0.713, p < 0.001). The relatively high frequency of ipsilateral overflow and mirror dystonia in patients with FHD has both pathophysiological and therapeutic implications. In this study, the severity of dystonia was significantly correlated with motor overflow in multiple tasks.