Differential diagnosis between Parkinson's disease and essential tremor using the smartphone's accelerometer

Background: The differential diagnosis between patients with essential tremor (ET) and those with Parkinson's disease (PD) whose main manifestation is tremor may be difficult unless using complex neuroimaging techniques such as 123I-FP-CIT SPECT. We considered that using smartphone's accelerometer to stablish a diagnostic test based on time-frequency differences between PD an ET could support the clinical diagnosis. Methods: The study was carried out in 17 patients with PD, 16 patients with ET, 12 healthy volunteers and 7 patients with tremor of undecided diagnosis (TUD), who were re-evaluated one year after the first visit to reach the definite diagnosis. The smartphone was placed over the hand dorsum to record epochs of 30 s at rest and 30 s during arm stretching. We generated frequency power spectra and calculated receiver operating characteristics curves (ROC) curves of total spectral power, to establish a threshold to separate subjects with and without tremor. In patients with PD and ET, we found that the ROC curve of relative energy was the feature discriminating better between the two groups. This threshold was then used to classify the TUD patients. Results: We could correctly classify 49 out of 52 subjects in the category with/without tremor (97.96% sensitivity and 83.3% specificity) and 27 out of 32 patients in the category PD/ET (84.38% discrimination accuracy). Among TUD patients, 2 of 2 PD and 2 of 4 ET were correctly classified, and one patient having PD plus ET was classified as PD. Conclusions: Based on the analysis of smartphone accelerometer recordings, we found several kinematic features in the analysis of tremor that distinguished first between healthy subjects and patients and, ultimately, between PD and ET patients. The proposed method can give immediate results for the clinician to gain valuable information for the diagnosis of tremor. This can be useful in environments where more sophisticated diagnostic techniques are unavailable

A System for the Synchronized Recording of Sonomyography, Electromyography and Joint Angle

Ultrasound and electromyography (EMG) are two of the most commonly used diagnostic tools for the assessment of muscles. Recently, many studies reported the simultaneous collection of EMG signals and ultrasound images, which were normally amplified and digitized by different devices. However, there is lack of a systematic method to synchronize them and no study has reported the effects of ultrasound gel to the EMG signal collection during the simultaneous data collection. In this paper, we introduced a new method to synchronize ultrasound B-scan images, EMG signals, joint angles and other related signals (e.g. force and velocity signals) in real-time. The B-mode ultrasound images were simultaneously captured by the PC together with the surface EMG (SEMG) and the joint angle signal. The deformations of the forearm muscles induced by wrist motions were extracted from a sequence of ultrasound images, named as Sonomyography (SMG). Preliminary experiments demonstrated that the proposed method could reliably collect the synchronized ultrasound images, SEMG signals and joint angle signals in real-time. In addition, the effect of ultrasound gel on the SEMG signals when the EMG electrodes were close to the ultrasound probe was studied. It was found that the SEMG signals were not significantly affected by the amount of the ultrasound gel. The system is being used for the study of contractions of various muscles as well as the muscle fatigue

Apraxia and motor dysfunction in corticobasal syndrome

Background: Corticobasal syndrome (CBS) is characterized by multifaceted motor system dysfunction and cognitive disturbance; distinctive clinical features include limb apraxia and visuospatial dysfunction. Transcranial magnetic stimulation (TMS) has been used to study motor system dysfunction in CBS, but the relationship of TMS parameters to clinical features has not been studied. The present study explored several hypotheses; firstly, that limb apraxia may be partly due to visuospatial impairment in CBS. Secondly, that motor system dysfunction can be demonstrated in CBS, using threshold-tracking TMS, and is linked to limb apraxia. Finally, that atrophy of the primary motor cortex, studied using voxel-based morphometry analysis (VBM), is associated with motor system dysfunction and limb apraxia in CBS.   Methods: Imitation of meaningful and meaningless hand gestures was graded to assess limb apraxia, while cognitive performance was assessed using the Addenbrooke's Cognitive Examination - Revised (ACE-R), with particular emphasis placed on the visuospatial subtask. Patients underwent TMS, to assess cortical function, and VBM.   Results: In total, 17 patients with CBS (7 male, 10 female; mean age 64.4+/2 6.6 years) were studied and compared to 17 matched control subjects. Of the CBS patients, 23.5% had a relatively inexcitable motor cortex, with evidence of cortical dysfunction in the remaining 76.5% patients. Reduced resting motor threshold, and visuospatial performance, correlated with limb apraxia. Patients with a resting motor threshold <50% performed significantly worse on the visuospatial sub-task of the ACE-R than other CBS patients. Cortical function correlated with atrophy of the primary and pre-motor cortices, and the thalamus, while apraxia correlated with atrophy of the pre-motor and parietal cortices.   Conclusions: Cortical dysfunction appears to underlie the core clinical features of CBS, and is associated with atrophy of the primary motor and pre-motor cortices, as well as the thalamus, while apraxia correlates with pre-motor and parietal atrophy

Voluntary motor drive: possible reduction in Tourette syndrome

Electrophysiologically, Tourette syndrome (TS) is characterized by shortened cortical silent period (CSP), reflecting decreased motor inhibition. However, voluntary versus involuntary aspects of inhibitory functions in TS are not well understood. Hence, investigating voluntary motor drive (VMD) could help to elucidate this issue. A group of 14 healthy adolescents was compared with subjects of same age suffering from TS with (N = 6) and without (N = 6) presence of distal tics. Basic resting and active motor thresholds (RMT and AMT, respectively) as well as suprathreshold transcranial magnetic stimulation-conditioned RMT and AMT were determined during the CSP. The difference between AMT and RMT was considered as VMD quantum. No group-differences were found in RMT or AMT. Subjects with distal tics showed reduced VMD compared to healthy controls while patients without distal tics did not differ from controls. In the second half of CSP, patients with distal tics showed also diminished VMD compared to tic-patients without distal tics. The findings support the notion, that TS shows possible reduction of VMD and is associated with central motor threshold alterations confined to the very motor networks related to the tics observed

‘Costa da Morte’ ataxia is spinocerebellar ataxia 36: clinical and genetic characterization

Spinocerebellar ataxia 36 has been recently described in Japanese families as a new type of spinocerebellar ataxia with motor neuron signs. It is caused by a GGCCTG repeat expansion in intron 1 of NOP56. Family interview and document research allowed us to reconstruct two extensive, multigenerational kindreds stemming from the same village (Costa da Morte in Galicia, Spain), in the 17th century. We found the presence of the spinocerebellar ataxia 36 mutation co-segregating with disease in these families in whom we had previously identified an ∼0.8 Mb linkage region to chromosome 20 p. Subsequent screening revealed the NOP56 expansion in eight additional Galician ataxia kindreds. While normal alleles contain 5–14 hexanucleotide repeats, expanded alleles range from ∼650 to 2500 repeats, within a shared haplotype. Further expansion of repeat size was frequent, especially upon paternal transmission, while instances of allele contraction were observed in maternal transmissions. We found a total of 63 individuals carrying the mutation, 44 of whom were confirmed to be clinically affected; over 400 people are at risk. We describe here the detailed clinical picture, consisting of a late-onset, slowly progressive cerebellar syndrome with variable eye movement abnormalities and sensorineural hearing loss. There were signs of denervation in the tongue, as well as mild pyramidal signs, but otherwise no signs of classical amyotrophic lateral sclerosis. Magnetic resonance imaging findings were consistent with the clinical course, showing atrophy of the cerebellar vermis in initial stages, later evolving to a pattern of olivo-ponto-cerebellar atrophy. We estimated the origin of the founder mutation in Galicia to have occurred ∼1275 years ago. Out of 160 Galician families with spinocerebellar ataxia, 10 (6.3%) were found to have spinocerebellar ataxia 36, while 15 (9.4%) showed other of the routinely tested dominant spinocerebellar ataxia types. Spinocerebellar ataxia 36 is thus, so far, the most frequent dominant spinocerebellar ataxia in this region, which may have implications for American countries associated with traditional Spanish emigration

Long-latency modulation of motor cortex excitability by ipsilateral posterior inferior frontal gyrus and pre-supplementary motor area

The primary motor cortex (M1) is strongly influenced by several frontal regions. Dual-site transcranial magnetic stimulation (dsTMS) has highlighted the timing of early (<40 ms) prefrontal/premotor influences over M1. Here we used dsTMS to investigate, for the first time, longer-latency causal interactions of the posterior inferior frontal gyrus (pIFG) and pre-supplementary motor area (pre-SMA) with M1 at rest. A suprathreshold test stimulus (TS) was applied over M1 producing a motor-evoked potential (MEP) in the relaxed hand. Either a subthreshold or a suprathreshold conditioning stimulus (CS) was administered over ipsilateral pIFG/pre-SMA sites before the TS at different CS-TS inter-stimulus intervals (ISIs: 40-150 ms). Independently of intensity, CS over pIFG and pre-SMA (but not over a control site) inhibited MEPs at an ISI of 40 ms. The CS over pIFG produced a second peak of inhibition at an ISI of 150 ms. Additionally, facilitatory modulations were found at an ISI of 60 ms, with supra-but not subthreshold CS intensities. These findings suggest differential modulatory roles of pIFG and pre-SMA in M1 excitability. In particular, the pIFG-but not the pre-SMA-exerts intensity-dependent modulatory influences over M1 within the explored time window of 40-150 ms, evidencing fine-tuned control of M1 output

Protocolo de cribado, diagnóstico y tratamiento de la enfermedad de Chagas en mujeres embarazadas latinoamericanas y en sus hijos

Malaltia de Chagas; Dones embarassades llatinoamericanes; Salut maternoinfantilEnfermedad de Chagas; Mujeres embarazadas latinoamericanas; Salud maternoinfantilChagas disease; Latin american pregnant women; Maternal and child healthLa malaltia de Chagas (MCH) continua sent un problema important de salut pública. L’OMS estima que en el món hi ha 8 milions de persones infectades per Trypanosoma cruzi, la majoria a l’Amèrica Llatina. En països no endèmics, com és el cas del nostre entorn, l’MCH s’observa en persones infectades que provenen de països endèmics o en infants nascuts en països no endèmics, però la mare dels quals ha estat infectada (transmissió congènita). A Catalunya, per tal de fer el control i la vigilància de l’MCH, l’any 2010 es va posar en marxa el Programa de prevenció i control de la malaltia de Chagas congènita a Catalunya, coordinat pel Departament de Salut i que inclou el diagnòstic, el control, el seguiment i el tractament de l’MCH congènita dirigits a les dones embarassades i als seus fills. En el marc del Programa, es va elaborar el Protocol de cribratge i diagnòstic de malaltia de Chagas en dones embarassades llatinoamericanes i en els seus fills, que es va editar el 2010. Aquest document va ser fruit de l’esforç conjunt de professionals sanitaris experts en la malaltia, de diferents societats científiques i de professionals del Departament de Salut de la Generalitat de Catalunya, amb el suport del Grup de Treball de Països No Endèmics i del Departament de Control de Malalties Tropicals Oblidades de l’OMS. El Protocol que es presenta, a més d’incloure les mateixes línies que la primera edició, disposa d’actualitzacions de diferents aspectes clínics, de diagnòstic i de vigilància epidemiològica basats en l’experiència i l’evidència observades durant aquests vuit anys del Programa de prevenció i control de la malaltia de Chagas congènita a Catalunya. Durant aquests darrers anys, s’ha reforçat la perspectiva de salut pública en el Programa, en el qual han participat un gran nombre de professionals de la xarxa assistencial i agents comunitaris de salut amb l’objectiu de reduir l’efecte de la transmissió vertical de l’MCH a Catalunya. La primera part del document recull les característiques clíniques de l’MCH que, encara que és d’aparició relativament recent en el nostre entorn, gràcies a la informació facilitada tant en l’àmbit sanitari com en l’àmbit comunitari durant els últims anys, ha deixat de ser una malaltia oblidada i desconeguda a Catalunya. En els darrers anys, els avenços i l’experiència en el nostre entorn en el diagnòstic de l’MCH ens han fet arribar a un consens sobre la utilització de mètodes directes moleculars, tal com es descriu en aquest Protocol. Així mateix, la concreció de dades epidemiològiques sobre prevalença d’infecció i incidència de casos de la malaltia ha millorat molt gràcies a la vigilància i notificació de dades recollides en el marc del Programa de prevenció i control de la malaltia de Chagas congènita a Catalunya pels professionals que formen part del Grup de Treball de la Malaltia de Chagas Congènita. En aquest aspecte i per tal de millorar-ne el control s’han incorporat els metges de família i salut comunitària, ja que són uns dels professionals clau que es troben més propers als pacients. Un aspecte fonamental que es desprèn d’aquest document i del funcionament del Programa és la multidisciplinarietat. El repte del sistema de salut i de la vigilància de la salut pública és la coordinació i el treball dels professionals de diferents àmbits sanitaris, com poden ser els ginecòlegs, els microbiòlegs, els llevadors, els pediatres d’atenció primària i hospitalària, els metges de família i salut comunitària, el personal d’infermeria, els infectòlegs, els epidemiòlegs i els agents de salut comunitària que treballen de manera conjunta per a l’assoliment de l’objectiu plantejat. El present Protocol constitueix un document eminentment pràctic, mitjançant el qual els professionals sanitaris disposen dels elements essencials per a la realització del cribratge en la dona embarassada. A partir d’aquest Protocol s’espera també aconseguir la detecció i el tractament precoç dels casos d’MCH en la població pediàtrica, nadons i altres fills a Catalunya, amb l’objectiu últim de millorar la salut maternoinfantil a Catalunya.La enfermedad de Chagas (ECH) sigue siendo un problema importante de salud pública. La OMS estima que en el mundo hay 8 millones de personas infectadas por Trypanosoma cruzi, la mayoría en América Latina. En países no endémicos, como es el caso de nuestro entorno, la ECH se observa en personas infectadas que provienen de países endémicos o en niños nacidos en países no endémicos, pero cuya madre ha sido infectada (transmisión congénita). En Cataluña, para hacer el control y la vigilancia de la ECH, en 2010 se puso en marcha el Programa de prevención y control de la enfermedad de Chagas congénita en Cataluña, coordinado por el Departamento de Salud y que incluye el diagnóstico, el control, el seguimiento y el tratamiento de la ECH congénita dirigidos a las mujeres embarazadas y a sus hijos. En el marco del Programa, se elaboró el Protocolo de cribado y diagnóstico de enfermedad de Chagas en mujeres embarazadas latinoamericanas y en sus hijos, que se editó en 2010. Este documento fue fruto del esfuerzo conjunto de profesionales sanitarios expertos en la enfermedad, de diferentes sociedades científicas y de profesionales del Departamento de Salud de la Generalidad de Cataluña, con el apoyo del Grupo de Trabajo de Países No Endémicos y del Departamento de Control de Enfermedades Tropicales Olvidadas de la OMS. El Protocolo que se presenta, además de incluir las mismas líneas que la primera edición, dispone de actualizaciones de diferentes aspectos clínicos, de diagnóstico y de vigilancia epidemiológica basados en la experiencia y la evidencia observadas durante estos ocho años del Programa de prevención y control de la enfermedad de Chagas congénita en Cataluña. Durante estos últimos años, se ha reforzado la perspectiva de salud pública en el Programa, en el que han participado un gran número de profesionales de la red asistencial y agentes comunitarios de salud con el objetivo de reducir el efecto de la transmisión vertical del ECH en Cataluña. La primera parte del documento recoge las características clínicas de la ECH que, aunque es de aparición relativamente reciente en nuestro entorno, gracias a la información facilitada tanto en el ámbito sanitario como en el ámbito comunitario durante los últimos años, ha dejado de ser una enfermedad olvidada y desconocida en Cataluña. En los últimos años, los avances y la experiencia en nuestro entorno en el diagnóstico de la ECH nos han hecho llegar a un consenso sobre la utilización de métodos directos moleculares, tal como se describe en el presente Protocolo. Asimismo, la concreción de datos epidemiológicos sobre prevalencia de infección e incidencia de casos de la enfermedad ha mejorado mucho gracias a la vigilancia y notificación de datos recogidos en el marco del Programa de prevención y control de la enfermedad de Chagas congénita en Cataluña por los profesionales que forman parte del Grupo de Trabajo de la Enfermedad de Chagas Congénita. En este aspecto y para mejorar su control se han incorporado los médicos de familia y salud comunitaria, ya que son unos de los profesionales clave que se encuentran más cercanos a los pacientes. Un aspecto fundamental que se desprende de este documento y del funcionamiento del Programa es la multidisciplinariedad. El reto del sistema de salud y de la vigilancia de la salud pública es la coordinación y el trabajo de los profesionales de diferentes ámbitos sanitarios, como pueden ser ginecólogos, microbiólogos, comadrones, pediatras de atención primaria y hospitalaria, médicos de familia y salud comunitaria, personal de enfermería, infectólogos, epidemiólogos y agentes de salud comunitaria que trabajan de manera conjunta para el logro del objetivo planteado. El presente Protocolo constituye un documento eminentemente práctico, mediante el cual los profesionales sanitarios disponen de los elementos esenciales para la realización del cribado en la mujer embarazada. A partir de este Protocolo se espera también conseguir la detección y el tratamiento precoz de los casos de ECH en la población pediátrica, bebés y otros hijos en Cataluña, con el objetivo último de mejorar la salud maternoinfantil en Cataluña.Chagas disease (CHD) continues to be a major public health problem. The WHO estimates that there are 8 million people in the world infected with Trypanosoma cruzi, the majority in Latin America. In non-endemic countries, as is the case in our environment, CHD is seen in infected people who come from endemic countries or children born in non-endemic countries, but whose mother has been infected (congenital transmission). In Catalonia, in order to control and monitor the CHD, in 2010 the Program for the Prevention and Control of Congenital Chagas' Disease in Catalonia was launched, coordinated by the Department of Health and includes diagnosis, control, follow-up and treatment of congenital CHD directed at pregnant women and their children. Within the framework of the Program, the Protocol for the Screening and Diagnosis of Chagas' Disease in Latin American pregnant women and their children was prepared, which was published in 2010. This document was the result of the joint effort of health professionals who are experts in the disease, of different scientific societies and professionals of the Department of Health of the Government of Catalonia, with the support of the Working Group of Non-endemic Countries and the Department of Control of Forgotten Tropical Diseases of WHO. The Protocol that is presented, in addition to including the same lines as the first edition, has updates on different clinical, diagnostic and epidemiological surveillance aspects based on the experience and evidence observed during these eight years of the Prevention and Control Program. Congenital Chagas disease in Catalonia. During these last years, the perspective of public health in the Program has been reinforced, in which a large number of professionals of the health care network and community health agents have participated with the aim of reducing the effect of the vertical transmission of CHD in Catalonia. The first part of the document includes the clinical characteristics of the CHD that, although it is relatively recent in our environment, thanks to the information provided both in the health field and in the community in recent years, has ceased to be a disease forgotten and unknown in Catalonia. In recent years, the advances and experience in our environment in the diagnosis of CHD have led us to reach a consensus on the use of direct molecular methods, as described in this Protocol. Likewise, the specification of epidemiological data on prevalence of infection and incidence of cases of the disease has improved greatly thanks to the monitoring and reporting of data collected within the framework of the Program for the Prevention and Control of Congenital Chagas' Disease in Catalonia by professionals. that are part of the Working Group on Congenital Chagas Disease. In this aspect and to improve their control, family doctors and community health have been incorporated, since they are one of the key professionals who are closest to patients. A fundamental aspect that emerges from this document and the operation of the Program is multidisciplinarity. The challenge of the health system and public health surveillance is the coordination and work of professionals from different health areas, such as gynecologists, microbiologists, midwives, pediatricians of primary and hospital care, family physicians and community health , nurses, infectious disease specialists, epidemiologists and community health workers who work together to achieve the stated objective. This Protocol is an eminently practical document, through which health professionals have the essential elements for carrying out screening in pregnant women. Based on this Protocol, it is also expected to achieve the detection and early treatment of cases of CHD in the pediatric population, babies and other children in Catalonia, with the ultimate goal of improving maternal and child health in Catalonia

Temporal relationship between perceptual and physiological events triggered by nociceptive heat stimuli

A combined assessment tool for the perceptual-motor aspects of pain processing will be valuable to clinicians. Fifteen healthy subjects were exposed to contact-heat stimulation (Pathway, Medoc, Israel) to assess perception through a simple task (motor response or conscious appraisal of the time the stimulus was felt) or with a dual task (both responses). The outcome measure was the temporal relationship between contact heat evoked potentials (CHEPS), reaction time (RT) and conscious awareness (AW). There were different temporal profiles for CHEPs, RT and AW to changes in stimulus intensity, AW being the least affected. Performing the dual task led to a significantly more pronounced effect on RT than on AW, while CHEPS were not influenced by task performance. Our results support the dissociation between physiological, behavioral and cognitive events elicited by nociceptive stimuli. The time of conscious appraisal of stimulus occurrence is a complementary information to other responses such as evoked potentials or behavioral tasks. The combined assessment of physiological and behavioral aspects of pain processing may provide clinicians with information on the different paths followed by nociceptive afferent inputs in the central nervous system.The study was carried out in part thanks to funds from grants: PI1300526 from Fondo de Investigaciones Sanitarias to J. Valls-Sole, ESPY-112/18 from Instituto de Salud Carlos III and Grant PRX12/00349 from Government of Spain to J. M. Castellote.S