Thomas Picht

Charité Universitätsmedizin Berlin | Charité · Department of Neurosurgery with Pediatric Neurosurgery

Background: Damage to the supplementary motor area (SMA) for example during surgery can lead to impairments of motor and language function. A detailed preoperative mapping of functional boarders of the SMA could therefore aid preoperative diagnostics in these patients. Objective: The aim of this study was the development of a repetitive nTMS protoc...

People with tumours in specific brain sites might face difficulties in tasks with different linguistic material. Previous lesion-symptom mapping studies (VLSM) demonstrated that people with tumours in posterior temporal regions have more severe linguistic impairments. However, to the best of our knowledge, preoperative performance and lesion locati...

Background: The medical technical innovations over the last decade have made operations in the highly sensitive regions of the brain much safer. Objective: Presentation of how far computer assistance and robotics have become incorporated into clinical neurosurgery. Material and method: Evaluation of the scientific literature and analysis of th...

Visual object naming (vON) is the most commonly applied linguistic test during awake surgeries with electrical stimulation mapping. Little is known about the predictive value of general preoperative linguistic and cognitive function for the intraoperative object naming ability of the patient. We aimed at analyzing these correlations, in order to po...

Three-dimensional exoscopes have been designed to overcome certain insufficiencies of operative microscopes. We aimed to explore the clinical use in various spinal surgeries. We performed surgery on patients with different spine entities in a neurosurgical department according to the current standard operating procedures over a 4-week period of tim...

Introduction This study explores the feasibility of implementing a tractography-based navigated transcranial magnetic stimulation (nTMS) language mapping protocol targeting cortical terminations of the arcuate fasciculus (AF). We compared the results and distribution of errors from the new protocol to an established perisylvian nTMS protocol that s...

OBJECTIVE Surgical resection of gliomas involving the supplementary motor area (SMA) frequently results in SMA syndrome, a symptom complex characterized by transient akinesia and mutism. Because the factors influencing patient functional outcomes after surgery remain elusive, the authors investigated network-based predictors in a multicentric cohor...

OBJECTIVE Training of residents is an essential but time-consuming and costly task in the surgical disciplines. During the coronavirus disease 2019 pandemic, surgical education became even more challenging because of the reduced caseload due to the increased shift to corona care. In this context, augmented 360° 3D virtual reality (VR) videos of sur...

Along tract statistics enables white matter characterization using various diffusion MRI (dMRI) metrics. These diffusion models reveal detailed insights into white matter microstructural changes with development, pathology, and function. Here, we aim at assessing the clinical utility of dMRI metrics along the corticospinal tract, investigating whet...

Objective: This study explores the feasibility of implementing a tractography-based navigated transcranial magnetic stimulation (nTMS) language mapping protocol which targets cortical terminations of the arcuate fasciculus (AF). We compared the results and distribution of errors from this protocol to a preceding nTMS protocol which stimulated over...

Background: Bell’s palsy develops due to a lesion of the facial nerve and might occur idiopathic, as a result of masses in the cerebello-pontine angle or brainstem or as a result of trauma or surgery. This prospective study aims to evaluate cortical reorganization after facial nerve palsy by means of navigated transcranial magnetic stimulation (nTM...

Introduction: The accessory nerve is frequently affected by iatrogenic injury which may cause major disability due to a loss of function in the trapezius muscle (trap) and/or the sternocleidomastoid muscle (scm). Navigated transcranial magnetic stimulation (nTMS) may be a valuable tool to quantify aspects of cortical motor reorganization and suppor...

Object Recent studies demonstrated that gross total resection of brain metastases cannot always be achieved. Subtotal resection (STR) can result in an early recurrence and might affect patient survival. We initiated a prospective observational study to establish a MRI-based risk assessment for incomplete resection of brain metastases. Methods All...

Brain tumors cause local structural impairments of the cerebral network. Moreover, brain tumors can also affect functional brain networks more distant from the lesion. In this study, we analyzed the impact of glioma WHO grade II-IV tumors on grey and white matter in relation to impaired language function. In a retrospective analysis of 60 patients,...

Stereoscopic imaging has increasingly been used in anatomical teaching and neurosurgery. The aim of our study was to analyze the potential utility of stereoscopic imaging as a tool for memorizing neurosurgical patient cases compared to conventional monoscopic visualization. A total of 16 residents and 6 consultants from the Department of Neurosurge...

Gliomas that infiltrate networks and systems, such as the motor system, often lead to substantial functional impairment in multiple systems. Network-based statistics (NBS) allow to assess local network differences and graph theoretical analyses enable investigation of global and local network properties. Here, we used network measures to characteri...

Low-frequency repetitive transcranial magnetic stimulation (rTMS) is capable of inducing changes in the functional organization of underlying brain regions, however, often at the cost of long stimulation protocols over several weeks. As these protocols can be difficult to implement in clinical settings, the aim of the present pilot study was to sho...

Exoscopic surgery promises alleviation of physical strain, improved intraoperative visualization and facilitation of the clinical workflow. In this prospective observational study, we investigate the clinical usability of a novel 3D4K-exoscope in routine neurosurgical interventions. Questionnaires on the use of the exoscope were carried out. Exempl...

Objective: With a growing appreciation for interindividual anatomical variability and patient-specific brain connectivity, advanced imaging sequences offer the opportunity to directly visualize anatomical targets for deep brain stimulation (DBS). The lack of quantitative evidence demonstrating their clinical utility, however, has hindered their br...

Background Augmented reality (AR) has the potential to support complex neurosurgical interventions by including visual information seamlessly. This study examines intraoperative visualization parameters and clinical impact of AR in brain tumor surgery. Methods Fifty-five intracranial lesions, operated either with AR-navigated microscope ( n = 39)...

Background: Surgical planning with nTMS-based tractography is proven to increase safety during surgery. A preoperative risk stratification model has been published based on the M1 infiltration, RMT ratio, and tumor to corticospinal tract distance (TTD). The correlation of TTD with corticospinal tract to resection cavity distance (TRD) and outcome...

OBJECTIVES Surgical resection of gliomas involving the supplementary motor area (SMA) frequently results in a symptom complex commonly described as „SMA syndrome“, which is characterized by transient contralateral akinesia and mutism. As factors potentially influencing the severity and duration of symptoms still remain elusive, we aim to further in...

Objective: With a growing appreciation for interindividual anatomical variability and patient-specific brain connectivity, advanced imaging sequences offer the opportunity to directly visualize anatomical targets for deep brain stimulation (DBS). The lack of quantitative evidence demonstrating their clinical utility, however, has hindered their bro...

Objective: The authors sought to validate the navigated transcranial magnetic stimulation (nTMS)-based risk stratification model. The postoperative motor outcome in glioma surgery may be preoperatively predicted based on data derived by nTMS. The tumor-to-tract distance (TTD) and the interhemispheric resting motor threshold (RMT) ratio (as a surro...

OBJECTIVE Motor cortical dysfunction has been shown to be reversible in patients with unilateral atherosclerotic disease after cerebral revascularization. Moyamoya vasculopathy (MMV) is a rare bilateral stenoocclusive cerebrovascular disease. The aim of this study was to analyze the corticospinal excitability and the role of bypass surgery in resto...

Brain tumors cause local structural impairments of the cerebral network. Moreover, brain tumors can also affect functional brain networks more distant from the lesion. In this study, we analyzed the impact of glioma WHO grade II-IV tumors on grey and white matter in relation to impaired language function. In a retrospective analysis of 60 patients,...

In the present study, we combined dMRI and nTMS during an action naming task with finite verbs (Ohlerth et al., 2020) to investigate the neural underpinnings of transitive and unergative verbs. After performing fiber tracking of the left and right AF (Fekonja et al., 2019), we identified and stimulated frontal, parietal, and temporal cortical termi...

Along tract statistics enables white matter characterization using various diffusion MRI (dMRI) metrics. Here, we applied a machine learning (ML) method to assess the clinical utility of dMRI metrics along corticospinal tracts (CST), investigating whether motor glioma patients can be classified with respect to their motor status. The ML-based analy...

Objective: Current literature debates the role of newly developed three-dimensional (3D) Exoscopes in the daily routine of neurosurgical practice. So far, only a small number of cadaver lab studies or case reports have examined the novel Aesculap Aeos Three-Dimensional Robotic Digital Microscope. This study aims to evaluate the grade of satisfacti...

Cortical plasticity is the brain’s capability of decoding new information through growth and reorganization over our whole life spam. It is the basis for good outcomes after reinnervation and for rehabilitation of adult and obstetric brachial plexus injury. Knowledge about cortical reorganization is crucial to reconstructive surgeons and physiother...

Objective: Visualization of subcortical language pathways by means of diffusion tensor imaging-fiber tracking (DTI-FT) is evolving as an important tool for surgical planning and decision making in patients with language-suspect brain tumors. Repetitive navigated transcranial magnetic stimulation (rTMS) cortical language mapping noninvasively provi...

Gliomas that infiltrate networks and systems, such as the motor system, often lead to substantial functional impairment in multiple systems. Network-based statistics (NBS) allow to 25 assess local network differences (1) and graph theoretical analyses (2) enable investigation of global and local network properties. Here, we used network measures to...

Background The resection of a motor-eloquent glioma should be guided by intraoperative neurophysiological monitoring (IOM) but its interpretation is often difficult and may (unnecessarily) lead to subtotal resection. Navigated transcranial magnetic stimulation (nTMS) combined with diffusion-tensor-imaging (DTI) is able to stratify patients with mot...

Background Navigated repetitive transcranial magnetic stimulation (nrTMS) is effective therapy for stroke patients. Neurorehabilitation could be supported by low-frequency stimulation of the non-damaged hemisphere to reduce transcallosal inhibition. Objective The present study examines the effect of postoperative nrTMS therapy of the unaffected he...

Background Exoscopic surgery promises alleviation of physical strain, improved intraoperative visualization and facilitation of the clinical workflow. In this prospective observational study we investigate the clinical usability of a novel 3D4K-exoscope in routine neurosurgical interventions. Methods Questionnaires on the use of the exoscope were c...

The physiological mechanisms of corticospinal excitability and factors influencing its measurement with transcranial magnetic stimulation are still poorly understood. A recent study reported an impact of functional connectivity (FC) between the primary motor cortex (M1) and the dorsal premotor cortex (PMd) on the resting motor threshold (RMT) of th...

Tumors infiltrating the motor system lead to significant disability, often caused by corticospinal tract injury. The delineation of the healthy-pathological white matter (WM) interface area, for which diffusion magnetic resonance imaging (dMRI) has shown promising potential, may improve treatment outcome. However, up to 90% of white matter (WM) vox...

Repetitive TMS (rTMS) allows for non-invasive and transient disruption of local neuronal functioning. We used machine learning approaches to assess whether brain tumor patients can be accurately classified into aphasic and non-aphasic groups using their rTMS language mapping results as input features. Given that each tumor affects the subject-speci...

Background Promoting a disruptive innovation in microsurgery, exoscopes promise alleviation of physical strain and improved image quality through digital visualization during microneurosurgical interventions. This study investigates the impact of a novel 3D4k hybrid exoscope (i.e., combining digital and optical visualization) on surgical performan...

OBJECTIVE Surgical resection of brainstem cavernomas is associated with high postoperative morbidity due to the density of local vulnerable structures. Classical mapping of pathways by diffusion tensor imaging (DTI) has proven to be unspecific and confusing in many cases. In the current study, the authors aimed to establish a more reliable, specifi...

Objectives Injury to major white matter pathways during language-area associated glioma surgery often leads to permanent loss of neurological function. The aim was to establish standardized tractography of language pathways as a predictor of language outcome in clinical neurosurgery. Methods We prospectively analyzed 50 surgical cases of patients...

Objectives In microneurosurgery, the operating microscope plays a vital role. The classical neurosurgical operation is bimanual, i.e. the microsurgical instruments are operated with both hands. Often, operations have to be carried out in narrow corridors at the depth of several centimeters. With the current technology, the operator must manually ad...

Tumors infiltrating the motor system lead to significant disability, often caused by corticospinal tract injury. The delineation of the healthy-pathological white matter (WM) interface area, for which diffusion magnetic resonance imaging (dMRI) has shown promising potential, may improve treatment outcome. However, up to 90% of white matter (WM) vox...

The physiological mechanisms of corticospinal excitability and factors influencing its measurement with transcranial magnetic stimulation are still poorly understood. A recent study reported an impact of functional connectivity between the primary motor cortex and dorsal premotor cortex on the resting motor threshold of the dominant hemisphere. We...

In preoperative planning for neurosurgery, both anatomical (diffusion imaging tractography) and functional tools (MR-navigated transcranial magnetic stimulation) are increasingly used to identify and preserve eloquent language structures specific to individuals. Using these tools in healthy adults shows that speech production errors occur mainly in...

In microsurgery, visualization systems such as the traditional surgical microscope are essential, as surgeons rely on the highly magnified stereoscopic view for performing their operative tasks. For well-aligned visual perspectives onto the operating field during surgery, precise adjustments of the positioning of the system are frequently required....

OBJECTIVE In adults, navigated transcranial magnetic stimulation (nTMS) has been established as a preoperative examination method for brain tumors in motor- and language-eloquent locations. However, the clinical relevance of nTMS in children with brain tumors is still unclear. Here, the authors present their initial experience with nTMS-based surgi...

Objective: Fully digital exoscopes (videoscopes) consist of a camera mounted on a robotic arm and a high resolution 3D video monitor positioned independently. Exoscopic surgery in general promises alleviation of physical strain and improved intraoperative visualization. This study investigates the clinical usability of a novel 3D4k videoscope in ne...

Background Increasing technico-manual complexity of procedures and time constraints necessitates effective neurosurgical training. For this purpose, both screen- and model-based simulations are under investigation. Approaches including 3D printed brains, gelatin composite models, and virtual environments have already been published. However, qualit...

OBJECTIVE Given the interindividual variance of functional language anatomy, risk prediction based merely on anatomical data is insufficient in language area–related brain tumor surgery, suggesting the need for direct cortical and subcortical mapping during awake surgery. Reliable, noninvasive preoperative methods of language localization hold the...

Objective Neuronavigated repetitive transcranial stimulation (rTMS) at a frequency of 1 Hz was shown to reduce excitability in underlying brain areas while increasing excitability in the opposite hemisphere. In stroke patients, this principle is used to normalize activity between the lesioned and healthy hemispheres and to facilitate rehabilitation...

Repetitive TMS (rTMS) allows to non-invasively and transiently disrupt local neuronal functioning. Its potential for mapping of language function is currently explored. Given the inter- individual heterogeneity of tumor impact on the language network and resulting rTMS derived functional mapping, we propose to use machine learning strategies to cla...