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1.
Brain ; 143(2): 582-596, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040563

RESUMO

Whilst exaggerated bursts of beta frequency band oscillatory synchronization in the subthalamic nucleus have been associated with motor impairment in Parkinson's disease, a plausible mechanism linking the two phenomena has been lacking. Here we test the hypothesis that increased synchronization denoted by beta bursting might compromise information coding capacity in basal ganglia networks. To this end we recorded local field potential activity in the subthalamic nucleus of 18 patients with Parkinson's disease as they executed cued upper and lower limb movements. We used the accuracy of local field potential-based classification of the limb to be moved on each trial as an index of the information held by the system with respect to intended action. Machine learning using the naïve Bayes conditional probability model was used for classification. Local field potential dynamics allowed accurate prediction of intended movements well ahead of their execution, with an area under the receiver operator characteristic curve of 0.80 ± 0.04 before imperative cues when the demanded action was known ahead of time. The presence of bursts of local field potential activity in the alpha, and even more so, in the beta frequency band significantly compromised the prediction of the limb to be moved. We conclude that low frequency bursts, particularly those in the beta band, restrict the capacity of the basal ganglia system to encode physiologically relevant information about intended actions. The current findings are also important as they suggest that local subthalamic activity may potentially be decoded to enable effector selection, in addition to force control in restorative brain-machine interface applications.

2.
GMS J Med Educ ; 36(6): Doc77, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31844649

RESUMO

Aim: Many medical universities rely these days on trained student tutors to enable faculty-wide undergraduate ultrasound training. However, there is neither consensus on an optimal method nor any developed and agreed standard in the training of these student tutors. Usually internships and courses are employed which have both a specific set of advantages and disadvantages. We conducted a prospective quasi-randomized study of assess the effects of three types of tutor training on the resulting improvement in scanning skills of their tutees. Methods: Three batches of student tutors were trained by a course only (C-group), by an internship only (I-group) or by a course and an internship (CI-group). The respective gains in ultrasound scanning skills of the tutees were measured prospectively. A total 75 of the 124 5th year medical students (60.5%) who attended the mandatory ultrasound course completed both pre- and post-exams on a voluntary basis. Within a limit of eight minutes and three images, they were asked to depict and label a maximum of 14 anatomical structures. Two blinded raters independently awarded two points for each label with an identifiable structure and one point for each label with a possibly identifiable structure. Results: In all three groups, the tutees improved significantly by more than doubling their pre-score results and comparably (Gains: C-group 9.19±5.73 points, p<.0001, I-group 9.77±4.81 points, p<.0001, CI-group 8.97±5.49 points, p<.0001). Conclusion: Student tutors, who were trained with a course or an internship or a course and an internship could teach scanning skills to 5th year medical students very effectively and with similar success.


Assuntos
Educação de Graduação em Medicina/métodos , Estudantes de Medicina , Ensino/organização & administração , Ultrassonografia , Desempenho Acadêmico/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados não Aleatórios como Assunto , Estudos Prospectivos
3.
J Neurol Neurosurg Psychiatry ; 90(12): 1310-1316, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31422368

RESUMO

BACKGROUND: Although rapid eye movement sleep behaviour disorder (RBD) in Parkinson's disease (PD) is associated with increased non-motor symptoms, its impact on the deep brain stimulation (DBS) outcome remains unclear. This is the first study to compare the post-DBS outcome between PD patients with RBD (PD-RBD+) and without (PD-RBD-). METHODS: We analysed data from PD patients who were treated with bilateral DBS in the nucleus subthalamicus. Assessments included night-polysomnography (only pre-DBS), and motor and non-motor assessments pre-DBS and post-DBS. RESULTS: Among 50 PD patients (29 males, mean age 62.5 years, 11.8 mean PD years), 24 (48%) had RBD. Pre-DBS, the two groups were equal in respect to sociodemographic features, disease duration and PD medications. A multivariate analysis showed that the clinical profile linked to motor, non-motor and quality of life features differed significantly between PD patients with and without RBD. The most discriminative elements were Unified Parkinson's Disease Rating Scale (UPDRS)-III, apathy and depression scores. Post-DBS, UPDRS-III, Epworth sleepiness scale and PD questionnaire improved significantly in both groups. UPDRS-II scores significantly improved in the PD-RBD+ group (-45%) but remained unchanged in the PD-RBD- group (-14%). The depression score improved significantly in the PD-RBD+ (-34%) and remained unchanged in the PD-RBD- group. The apathy score remained unchanged in the PD-RBD+ group but increased significantly in the PD-RBD- group (+33%). CONCLUSION: While pre-DBS, PD patients with and without RBD showed different clinical profiles, post-DBS, the clinical profiles were comparable between the two groups. In respect to depressive symptoms, apathy and activities of daily living, PD-RBD+ patients show favourable post-DBS outcome. These findings highlight the importance of RBD assessment prior to DBS surgery.

4.
Brain Stimul ; 12(5): 1127-1134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130498

RESUMO

BACKGROUND: Directional deep brain stimulation (dDBS) of the subthalamic nucleus for Parkinson's disease (PD) increases the therapeutic window. However, empirical programming of the neurostimulator becomes more complex given the increasing number of stimulation parameters. A better understanding of dDBS is needed to improve therapy and help guide postoperative programming. OBJECTIVE: To determine whether clinical effects of dDBS can be predicted in individual patients based on lead location and volume of tissue activated (VTA) modelling. METHODS: We analysed a prospective series of 28 PD patients. Imaging analysis and systematic clinical testing performed 4-6 months postoperatively yielded location, clinical efficacy and corresponding therapeutic windows for 272 directional contacts. We calculated the corresponding VTAs to build a probabilistic stimulation map using voxel-wise statistical analysis. RESULTS: We found a positive and statistically significant correlation between the overlap ratio of a patient's individual stimulation volume and the probabilistic map's sweet spot -defined as the 10% voxels with the highest clinical efficacy values (average Spearman's rho = 0.43, average p ≤ 0.036). Patients who had a larger therapeutic window with directional compared to omnidirectional stimulation had a larger distance between the electrode and the sweet spot centroid (average distances 2.3 vs. 1.5 mm, p = 0.0019). CONCLUSION: Our analysis provides new insights into how the definition of a probabilistic sweet spot based on directional stimulation data and individual VTA modelling can be applied to predict clinically effective directional stimulation and help guide clinicians with the intricate postoperative DBS programming.


Assuntos
Mapeamento Encefálico/métodos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Estudo de Prova de Conceito , Núcleo Subtalâmico/fisiologia , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Resultado do Tratamento
5.
BMC Med Educ ; 19(1): 170, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138197

RESUMO

BACKGROUND: Ultrasound is one of the most important imaging techniques in clinical medicine with unique advantages. Skills in ultrasound imaging are very usefull for physicians including novices and thus also mandated by the Task Force "National Competence-Based Learning Objectives for Undergraduate Medical Education" (NKLM) in Germany and as well as by the German Ultrasound Society (Deutsche Gesellschaft für Ultraschall in der Medizin, DEGUM). Since ultrasound is best learned hands-on in very small supervised groups, we developed and implemented a comprehensive ultrasound-curriculum for all undergraduate medical students of our faculty using a peer-teaching concept. METHODS: We used Kern's six-step model of curricular development comprising (1) problem identification and general needs assessment, (2) needs assessment of the targeted learners, (3) goals and objectives, (4) educational stategies, (5) implementation, and (6) evaluation and feedback. RESULTS: The developed curriculum covers basic ultrasound of the abdomen and the throat, eFAST (Extended Focused Assessment with Sonography for Trauma), lung-ultrasound, FEEL (Focused Echocardiography in Emergency Life Support) and compression duplex sonography of the thigh deep vein system. All 5th year medical students receive a 90 min lecture on ultrasound basics by a faculty member and then a 12.5 h hands-on course divided into three sessions with one student tutor for every 4 students. The students are provided with a script (PDF-File) that covers all the learning goals, including example images of pathologies. The student tutors are trained during a 1 week ultrasound course and a 21-day rotation through seven different ultrasound laboratories. In addition, they undergo a standardized 1.5 day didactical training. Prior to the implementation for all students, the overall course was tested on 27 volunteer students. These students rated (on a 6-point Likert scale from 1 = excellent to 6 = very poor) the satisfaction with the student tutors and the faculty members as 1.4 ± .9 (mean ± stddev) and 1.3 ± .5 respectively. CONCLUSION: A comprehensive ultrasound curriculum for all undergraduate medical students using a peer-teaching concept is feasible. Further studies are needed to evaluate in detail the learning outcomes for students and student tutors.


Assuntos
Currículo , Educação de Graduação em Medicina , Desenvolvimento de Programas , Ultrassonografia , Educação Baseada em Competências , Estudos de Viabilidade , Alemanha , Humanos , Avaliação de Programas e Projetos de Saúde
6.
BMC Med Educ ; 19(1): 125, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046757

RESUMO

BACKGROUND: In order to provide faculty-wide undergraduate ultrasound training in times of scarce resources, many medical faculties employ trained peer-student tutors to oversee the hands-on training. However, data to guide the training of ultrasound peer-student tutors are scarce. We conducted a prospective quasi-randomized study to assess the gain in theoretical knowledge and practical scanning skills of peer-student tutors who were trained with a course only, an internship only, or the combination of a course and an internship. METHODS: A total of 44 peer-student tutors were trained by a one-week course only (C-Group, n = 21), by an internship only (I-Group, n = 10) or by a course and an internship (CI-Group, n = 13). Prior to and after the completion of the training the peer-student tutors completed an MC-test (theoretical knowledge) and an OSCE (practical scanning skills). RESULTS: With all three education concepts, the peer-student tutors had significant and comparable gains in theoretical knowledge (C-group + 90%, I-group + 61.5%, CI-group + 114.0%) and practical scanning skills (C-group + 112.0%, I-group + 155.0% and CI-group + 123.5%), all p < 0.001. CONCLUSION: Peer-student tutors, who were trained with a course or an internship or a course and internship improved their theoretical knowledge and their practical scanning skills significantly and to a comparable degree.


Assuntos
Competência Clínica/normas , Educação de Graduação em Medicina/métodos , Avaliação Educacional/métodos , Medicina Interna/educação , Estudantes de Medicina , Ensino/normas , Ultrassonografia , Adulto , Difusão de Inovações , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Internato e Residência , Masculino , Modelos Educacionais , Grupo Associado , Estudos Prospectivos , Técnicas Psicológicas , Adulto Jovem
7.
Z Gastroenterol ; 57(6): 753-766, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30986884

RESUMO

PURPOSE: The purpose of this study was to analyze imaging findings in hepatic epithelioid hemangioendothelioma (HEHE) with a particular focus on contrast-enhanced ultrasound (CEUS). MATERIALS AND METHODS: This retrospective multicenter study included 10 patients with histologically proven HEHE from 5 European centers. All existing ultrasound images/videos were independently analyzed by 2 experienced examiners (DEGUM level III, internal medicine) using a standardized evaluation form. Patterns of contrast enhancement were correlated with computed tomography (CT), magnetic resonance imaging (MRI), and pathological findings. RESULTS: B-mode ultrasound, CEUS, CT, and MRI were performed in 90 %, 70 %, 100 %, and 90 % of patients, respectively. Multifocal HEHE could be observed in 80 % with affection of both liver lobes in 70 %. Analysis of CEUS revealed 3 characteristic patterns that correlated well with contrast patterns on CT and MRI: (a) peripheral nodular enhancement with centripetal fill-in and wash-out in the portal venous and late venous phase (PVLP), (b) rim-like arterial enhancement with wash-out in the PVLP, and (c) inversed target sign with/without wash-out in the PVLP. Wash-out in the PVLP as a sign suspicious of malignancy was observed in 6/7 patients (85.7 %). CONCLUSIONS: Knowledge of the different characteristic CEUS patterns is of importance to avoid misdiagnosis due to resemblance of patterns A and B to the much more common focal liver lesions hemangioma and intrahepatic cholangiocarcinoma. Of importance, sonographers should be aware that wash-out in the PVLP might be absent in some patients.


Assuntos
Neoplasias dos Ductos Biliares , Ductos Biliares Intra-Hepáticos , Hemangioendotelioma Epitelioide/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler em Cores/métodos , Adulto , Meios de Contraste/metabolismo , Humanos , Estudos Retrospectivos , Ultrassonografia
8.
Ultraschall Med ; 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31026863

RESUMO

PURPOSE: The aim of the current study was to evaluate point of care ultrasound (POCUS) in geriatric patients by echoscopy using a handheld ultrasound device (HHUSD, VScan) at bedside in comparison to a high-end ultrasound system (HEUS) as the gold standard. MATERIALS AND METHODS: Prospective observational study with a total of 112 geriatric patients. The ultrasound examinations were independently performed by two experienced blinded examiners with a portable handheld device and a high-end ultrasound device. The findings were compared with respect to diagnostic findings and therapeutic implications. RESULTS: The main indications for the ultrasound examinations were dyspnea (44.6 %), fall (frailty) (24.1 %) and fever (21.4 %). The most frequently found diagnoses were cystic lesions 32.1 % (35/109), hepatic vein congestion 19.3 % (21/109) and ascites 13.6 % (15/110). HHUSD delivered 13 false-negative findings in the abdomen resulting in an "overall sensitivity" of 89.5 %. The respective "overall specificity" was 99.6 % (7 false-positive diagnoses). HHUSD (versus HEUS data) resulted in 13.6 % (17.3 %) diagnostically relevant procedures in the abdomen and 0.9 % (0.9 %) in the thorax. Without HHUSD (HEUS) 95.7 % (100 %) of important pathological findings would have been missed. CONCLUSION: The small HHUSD tool improves clinical decision-making in immobile geriatric patients at the point of care (geriatric ward). In most cases, HHUSD allows sufficiently accurate yes/no diagnoses already at the bedside, thereby clarifying the leading symptoms for early clinical decision-making.

9.
Clin Neurophysiol ; 130(5): 727-738, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30903826

RESUMO

OBJECTIVE: Functional processes in the brain are segregated in both the spatial and spectral domain. Motivated by findings reported at the cortical level in healthy participants we test the hypothesis in the basal ganglia of Parkinson's disease patients that lower frequency beta band activity relates to motor circuits associated with the upper limb and higher beta frequencies with lower limb movements. METHODS: We recorded local field potentials (LFPs) from the subthalamic nucleus using segmented "directional" DBS leads, during which patients performed repetitive upper and lower limb movements. Movement-related spectral changes in the beta and gamma frequency-ranges and their spatial distributions were compared between limbs. RESULTS: We found that the beta desynchronization during leg movements is characterised by a strikingly greater involvement of higher beta frequencies (24-31 Hz), regardless of whether this was contralateral or ipsilateral to the limb moved. The spatial distribution of limb-specific movement-related changes was evident at higher gamma frequencies. CONCLUSION: Limb processing in the basal ganglia is differentially organised in the spectral and spatial domain and can be captured by directional DBS leads. SIGNIFICANCE: These findings may help to refine the use of the subthalamic LFPs as a control signal for adaptive DBS and neuroprosthetic devices.


Assuntos
Potenciais de Ação/fisiologia , Extremidade Inferior/fisiopatologia , Movimento/fisiologia , Doença de Parkinson/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Extremidade Superior/fisiopatologia , Adulto , Idoso , Gânglios da Base/fisiopatologia , Estimulação Encefálica Profunda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia
10.
J Int Med Res ; : 300060518816873, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30761931

RESUMO

Graves' disease (GD) is an autoimmune pathology characterized by hyperthyroidism and the presence of specific anti-thyroid antibodies. Neurological symptoms such as seizures, cognitive impairment, and tremor can be observed during the course of GD, but more complex movement disorders such as chorea and myoclonus are less frequent. The mechanisms underlying movement disorders in GD are not fully understood. While some authors relate movement disorders to thyroid dysfunction, others claim an autoimmune origin. We herein report a case involving a 60-year-old woman who presented with erratic, intricate movement disorders for which a medical workup revealed GD. During the 2-year follow-up period, her neurological symptoms evolved in parallel with her thyroid function, but not with her autoimmune anti-thyroid antibody level. Her neurological symptoms completely disappeared when she became euthyroid. We herein discuss the complicated clinicobiological relationship between thyroid function and movement disorders. This relationship involves several factors, including the impact of radioactive treatment. The present case emphasizes the importance of including thyroid function screening in the workup of unexplained movement disorders.

11.
J Neurosurg ; 131(3): 820-827, 2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30497206

RESUMO

OBJECTIVE: Deep brain stimulation (DBS) of the posterior subthalamic area (PSA) is an alternative to thalamic DBS for the treatment of essential tremor (ET). The dentato-rubro-thalamic tract (DRTT) has recently been proposed as the anatomical substrate underlying effective stimulation. For clinical purposes, depiction of the DRTT mainly depends on diffusion tensor imaging (DTI)-based tractography, which has some drawbacks. The objective of this study was to present an accurate targeting strategy for DBS of the PSA based on anatomical landmarks visible on MRI and to evaluate clinical effectiveness. METHODS: The authors performed a retrospective cohort study of a prospective series of 11 ET patients undergoing bilateral DBS of the PSA. The subthalamic nucleus and red nucleus served as anatomical landmarks to define the target point within the adjacent PSA on 3-T T2-weighted MRI. Stimulating contact (SC) positions with reference to the midcommissural point were analyzed and projected onto the stereotactic atlas of Morel. Postoperative outcome assessment after 6 and 12 months was based on change in Tremor Rating Scale (TRS) scores. RESULTS: Actual target position corresponded to the intended target based on anatomical landmarks depicted on MRI. The total TRS score was reduced (improved) from 47.2 ± 15.7 to 21.3 ± 10.7 (p < 0.001). No severe complication occurred. The mean SC position projected onto the PSA at the margin of the cerebellothalamic fascicle and the zona incerta. CONCLUSIONS: Targeting of the PSA based on anatomical landmarks representable on MRI is reliable and leads to accurate lead placement as well as good long-term clinical outcome.


Assuntos
Estimulação Encefálica Profunda , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/terapia , Núcleo Subtalâmico , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Neuroimage Clin ; 20: 868-874, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30282063

RESUMO

BACKGROUND: Accurate interindividual comparability of deep brain stimulation (DBS) lead locations in relation to the surrounding anatomical structures is of eminent importance to define and understand effective stimulation areas. The objective of the current work is to compare the accuracy of the DBS lead localisation relative to the STN in native space with four recently developed three-dimensional subcortical brain atlases in the MNI template space. Accuracy is reviewed by anatomical and volumetric analysis as well as intraoperative electrophysiological data. METHODS: Postoperative lead localisations of 10 patients (19 hemispheres) were analysed in each individual patient based on Brainlab software (native space) and after normalization into the MNI space and application of 4 different human brain atlases using Lead-DBS toolbox within Matlab (template space). Each patient's STN was manually segmented and the relation between the reconstructed lead and the STN was compared to the 4 atlas-based STN models by applying the Dice coefficient. The length of intraoperative electrophysiological STN activity along different microelectrode recording tracks was measured and compared to reconstructions in native and template space. Descriptive non-parametric statistical tests were used to calculate differences between the 4 different atlases. RESULTS: The mean STN volume of the study cohort was 153.3 ±â€¯40.3 mm3 (n = 19). This is similar to the STN volume of the DISTAL atlas (166 mm3; p = .22), but significantly larger compared to the other atlases tested in this study. The anatomical overlap of the lead-STN-reconstruction was highest for the DISTAL atlas (0.56 ±â€¯0.18) and lowest for the PD25 atlas (0.34 ±â€¯0.17). A total number of 47 MER trajectories through the STN were analysed. There was a statistically significant discrepancy of the electrophysiogical STN activity compared to the reconstructed STN of all four atlases (p < .0001). CONCLUSION: Lead reconstruction after normalization into the MNI template space and application of four different atlases led to different results in terms of the DBS lead position relative to the STN. Based on electrophysiological and imaging data, the DISTAL atlas led to the most accurate display of the reconstructed DBS lead relative to the DISTAL-based STN.


Assuntos
Estimulação Encefálica Profunda , Imageamento Tridimensional/métodos , Procedimentos Neurocirúrgicos/métodos , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/patologia , Atlas como Assunto , Humanos , Monitorização Neurofisiológica Intraoperatória/métodos , Imagem por Ressonância Magnética/métodos , Cuidados Pré-Operatórios , Núcleo Subtalâmico/cirurgia
13.
J Neurosurg ; 130(1): 99-108, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29570012

RESUMO

OBJECTIVE The dentatorubrothalamic tract (DRTT) has been suggested as the anatomical substrate for deep brain stimulation (DBS)-induced tremor alleviation. So far, little is known about how accurately and reliably tracking results correspond to the anatomical DRTT. The objective of this study was to systematically investigate and validate the results of different tractography approaches for surgical planning. METHODS The authors retrospectively analyzed 4 methodological approaches for diffusion tensor imaging (DTI)-based fiber tracking using different regions of interest in 6 patients with essential tremor. Tracking results were analyzed and validated with reference to MRI-based anatomical landmarks, were projected onto the stereotactic atlas of Morel at 3 predetermined levels (vertical levels -3.6, -1.8, and 0 mm below the anterior commissure-posterior commissure line), and were correlated to clinical outcome. RESULTS The 4 different methodologies for tracking the DRTT led to divergent results with respect to the MRI-based anatomical landmarks and when projected onto the stereotactic atlas of Morel. There was a statistically significant difference in the lateral and anteroposterior coordinates at the 3 vertical levels (p < 0.001, 2-way ANOVA). Different fractional anisotropy values ranging from 0.1 to 0.46 were required for anatomically plausible tracking results and led to varying degrees of success. Tracking results were not correlated to postoperative tremor reduction. CONCLUSIONS Different tracking methods can yield results with good anatomical approximation. The authors recommend using 3 regions of interest including the dentate nucleus of the cerebellum, the posterior subthalamic area, and the precentral gyrus to visualize the DRTT. Tracking results must be cautiously evaluated for anatomical plausibility and accuracy in each patient.


Assuntos
Núcleos Cerebelares/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Tremor Essencial/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Tremor Essencial/cirurgia , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
14.
Mov Disord ; 33(1): 159-164, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29150884

RESUMO

BACKGROUND: Although recently introduced directional DBS leads provide control of the stimulation field, programing is time-consuming. OBJECTIVES: Here, we validate local field potentials recorded from directional contacts as a predictor of the most efficient contacts for stimulation in patients with PD. METHODS: Intraoperative local field potentials were recorded from directional contacts in the STN of 12 patients and beta activity compared with the results of the clinical contact review performed after 4 to 7 months. RESULTS: Normalized beta activity was positively correlated with the contact's clinical efficacy. The two contacts with the highest beta activity included the most efficient stimulation contact in up to 92% and that with the widest therapeutic window in 74% of cases. CONCLUSION: Local field potentials predict the most efficient stimulation contacts and may provide a useful tool to expedite the selection of the optimal contact for directional DBS. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Ritmo beta/fisiologia , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Idoso , Estudos de Coortes , Eletrodos Implantados , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do Tratamento
15.
Oper Neurosurg (Hagerstown) ; 15(1): 66-71, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973406

RESUMO

BACKGROUND: Targeting accuracy in deep brain stimulation (DBS) surgery can be defined as the level of accordance between selected and anatomic real target reflected by characteristic electrophysiological results of microelectrode recording (MER). OBJECTIVE: To determine the correspondence between the preoperative predicted target based on modern 3-T magnetic resonance imaging (MRI) and intraoperative MER results separately on the initial and consecutive second side of surgery. METHODS: Retrospective cohort study of 86 trajectories of DBS electrodes implanted into the subthalamic nucleus (STN) of patients with Parkinson's disease. The entrance point of the electrode into the STN and the length of the electrode trajectory crossing the STN were determined by intraoperative MER findings and 3 T T2-weighted magnetic resonance images with 1-mm slice thickness. RESULTS: Average difference between MRI- and MER-based trajectory lengths crossing the STN was 0.28 ± 1.02 mm (95% CI: -0.51 to -0.05 mm). There was a statistically significant difference between the MRI- and MER-based entry points on the initial and second side of surgery (P = .04). Forty-three percent of the patients had a difference of more than ±1 mm of the MRI-based-predicted and the MER-based-determined entry points into the STN with values ranging from -3.0 to + 4.5 mm. CONCLUSION: STN MRI-based targeting is accurate in the majority of cases on the first and second side of surgery. In 43% of implanted electrodes, we found a relevant deviation of more than 1 mm, supporting the concept of MER as an important tool to guide and optimize targeting and electrode placement.


Assuntos
Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Microeletrodos , Procedimentos Neurocirúrgicos/métodos , Doença de Parkinson/terapia , Núcleo Subtalâmico/diagnóstico por imagem , Núcleo Subtalâmico/cirurgia , Humanos , Imagem por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/cirurgia , Estudos Retrospectivos
16.
PLoS One ; 12(12): e0190027, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29253029

RESUMO

OBJECTIVES: Sleep-wake disturbances (SWD) are frequent in Parkinson's disease (PD). The effect of deep brain stimulation (DBS) on SWD is poorly known. In this study we examined the subjective and objective sleep-wake profile and the quality of life (QoL) of PD patients in the context of subthalamic DBS. PATIENTS AND METHODS: We retrospectively analyzed data from PD patients and candidates for DBS in the nucleus suthalamicus (STN). Pre-DBS, sleep-wake assessments included subjective and objective (polysomnography, vigilance tests and actigraphy) measures. Post-DBS, subjective measures were collected. QoL was assessed using the Parkinson's Disease Questionnaire (PDQ-39) and the RAND SF-36-item Health Survey (RAND SF-36). RESULTS: Data from 74 PD patients (62% male, mean age 62.2 years, SD = 8.9) with a mean UPDRS-III (OFF) of 34.2 (SD = 14.8) and 11.8 (SD = 4.5) years under PD treatment were analyzed. Pre-DBS, daytime sleepiness, apathy, fatigue and depressive symptoms were present in 49%, 34%, 38% and 25% of patients respectively but not always as co-occurring symptoms. Sleep-wake disturbances were significantly correlated with QoL scores. One year after STN DBS, motor signs, QoL and sleepiness improved but apathy worsened. Changes in QoL were associated with changes in sleepiness and apathy but baseline sleep-wake functions were not predictive of STN DBS outcome. CONCLUSION: In PD patients presenting for STN DBS, subjective and objective sleep-wake disturbances are common and have a negative impact on QoL before and after neurosurgery. Given the current preliminary evidence, prospective observational studies assessing subjective and objective sleep-wake variables prior to and after DBS are needed.


Assuntos
Estimulação Encefálica Profunda/métodos , Doença de Parkinson/fisiopatologia , Qualidade de Vida , Transtornos do Sono-Vigília/fisiopatologia , Sono , Actigrafia , Idoso , Estudos de Coortes , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Polissonografia , Estudos Retrospectivos , Transtornos do Sono-Vigília/etiologia , Núcleo Subtalâmico/fisiologia , Inquéritos e Questionários , Vigília
17.
Stereotact Funct Neurosurg ; 95(4): 243-250, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28772275

RESUMO

BACKGROUND: Subthalamic nucleus (STN) stimulation has been recognized to control resting tremor in Parkinson disease. Similarly, thalamic stimulation (ventral intermediate nucleus; VIM) has shown tremor control in Parkinson disease, essential, and intention tremors. Recently, stimulation of the posterior subthalamic area (PSA) has been associated with excellent tremor control. Thus, the optimal site of stimulation may be located in the surrounding white matter. AIMS: The objective of this work was to investigate the area of stimulation by determining the contact location correlated with the best tremor control in STN/VIM patients. METHODS: The mean stimulation site and related volume of tissue activated (VTA) of 25 tremor patients (STN or VIM) were projected on the Morel atlas and compared to stimulation sites from other tremor studies. RESULTS: All patients showed a VTA that covered ≥50% of the area superior and medial to the STN or inferior to the VIM. Our stimulation areas suggest involvement of the more lateral and superior part of the dentato-rubro-thalamic tract (DRTT), whereas targets described in other studies seem to involve the DRTT in its more medial and inferior part when it crosses the PSA. CONCLUSIONS: According to anatomical and diffusion tensor imaging data, the DRTT might be the common structure stimulated at different portions within the PSA/caudal zona incerta.


Assuntos
Estimulação Encefálica Profunda/métodos , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/terapia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Núcleo Subtalâmico/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
18.
Z Gastroenterol ; 55(3): 277-290, 2017 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-28068731

RESUMO

In geriatric patients, ultrasound is the appropriate diagnostic technique to detect and to follow-up underlying and accompanying diseases of the heart, lung, liver, kidneys, pancreas, gastrointestinal tract and of arterial and venous vessels. Based on a systematic survey of the published literature, this review describes the value of ultrasound in geriatric patients focussing on point of care.


Assuntos
Avaliação Geriátrica/métodos , Testes Imediatos/normas , Guias de Prática Clínica como Assunto , Ultrassonografia/normas , Idoso , Idoso de 80 Anos ou mais , Medicina Baseada em Evidências , Feminino , Alemanha , Humanos , Masculino
19.
Z Med Phys ; 26(3): 251-8, 2016 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-26900096

RESUMO

AIM: To replace pictograms with pictocam pictures: A prospective blinded quality improvement study in documenting image orientation and localisation in abdominal ultrasound imaging. MATERIALS AND METHODS: A minicam was mounted on the ultrasound scanhead to record pictocam pictures. The primary examiner produced an ultrasound image together with the routinely embedded pictogram. Subsequently the pictogram was covered by the synchronically taken pictocam picture. Subsequently, the primary examiner assessed the pictograms and the second examiner the pictocam pictures (blinded to the pictogram findings of the primary examiner). RESULTS: A total of 679 paired pictogram and pictocam pictures were available from 114 patients. The localisation of the utrasound head showed an absolute or close agreement of 99.7% (677/679) with a 95% confidence interval of [98.94%-99.96%]. The angle of the ultrasound head showed an absolute or close agreement of 99.0% (672/679) with a 95% confidence interval of [97.98% - 99.58%]. CONCLUSION: This study shows that the pictogram can validely be replaced by a pictocam picture. The routine addition of a minicam to the ultrasound scanhead would thus not only improve the quality of the documentation, but would also result in time savings during examinations.


Assuntos
Abdome/diagnóstico por imagem , Gráficos por Computador , Documentação/métodos , Fotografação/métodos , Sistemas de Informação em Radiologia/organização & administração , Ultrassonografia/métodos , Documentação/normas , Humanos , Variações Dependentes do Observador , Melhoria de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Ultrassonografia/normas
20.
PLoS One ; 10(9): e0137868, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26366574

RESUMO

OBJECTIVE: Recent advances in different MRI sequences have enabled direct visualization and targeting of the Globus pallidus internus (GPi) for DBS surgery. Modified Driven Equilibrium Fourier Transform (MDEFT) MRI sequences provide high spatial resolution and an excellent contrast of the basal ganglia with low distortion. In this study, we investigate if MDEFT sequences yield accurate and reliable targeting of the GPi and compare direct targeting based on MDEFT sequences with atlas-based targeting. METHODS: 13 consecutive patients considered for bilateral GPi-DBS for dystonia or PD were included in this study. Preoperative targeting of the GPi was performed visually based on MDEFT sequences as well as by using standard atlas coordinates. Postoperative CT imaging was performed to calculate the location of the implanted leads as well as the active electrode(s). The coordinates of both visual and atlas based targets were compared. The stereotactic coordinates of the lead and active electrode(s) were calculated and projected on the segmented GPi. RESULTS: On MDEFT sequences the GPi was well demarcated in most patients. Compared to atlas-based planning the mean target coordinates were located significantly more posterior. Subgroup analysis showed a significant difference in the lateral coordinate between dystonia (LAT = 19.33 ± 0.90) and PD patients (LAT = 20.67 ± 1.69). Projected on the segmented preoperative GPi the active contacts of the DBS electrode in both dystonia and PD patients were located in the inferior and posterior part of the structure corresponding to the motor part of the GPi. CONCLUSIONS: MDEFT MRI sequences provide high spatial resolution and an excellent contrast enabling precise identification and direct visual targeting of the GPi. Compared to atlas-based targeting, it resulted in a significantly different mean location of our target. Furthermore, we observed a significant variability of the target among the PD and dystonia subpopulation suggesting accurate targeting for each individual patient.


Assuntos
Estimulação Encefálica Profunda/métodos , Distúrbios Distônicos/terapia , Globo Pálido/cirurgia , Imagem por Ressonância Magnética/métodos , Doença de Parkinson/terapia , Adulto , Idoso , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Prospectivos
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