Dylan Henssen

• MD PhD
• PostDoc Position at Radboud University Medical Centre (Radboudumc)

Background/Objectives: Neuroimaging biomarkers could offer more objective measures of the pain experience. This study investigated rT1/T2 maps of the brain as a novel biomarker for chronic pain in patients with central post-stroke pain (PSP) and persistent spinal pain syndrome type 2 (PSPS-II). Methods: Patients with PSP and PSPS-II were retrospect...

Background Patients with chronic pain due to persistent spinal pain syndrome Type 2 (PSPS Type 2) experience daily limitations in their physical activities. Physical, emotional, and social well‐being changes are usually measured with standardized, validated self‐reporting questionnaires. These reported data are subjective and are answered at a part...

Purpose Heterogeneity in clinical phenotypes has led to the description of different phenotypes of Alzheimer’s disease (AD). Besides the most frequent amnestic variant of AD (aAD), patients presenting with language deficits are diagnosed with logopenic variant primary progressive aphasia (lvPPA), whereas patients presenting with visual deficits are...

Purpose The loss of olfactory function is known to occur in patients suffering from (behavioral variant) frontotemporal dementia ((bv)FTD) and Alzheimer’s disease (AD), although different pathophysiological mechanisms underpin this clinical symptom in both disorders. This study assessed whether brain metabolism of the olfactory circuit as assessed...

Anatomy teachers urge students to come to education sessions at the dissection rooms as well-prepared as possible. To effectuate optimal preparation, assignments are designed to guide the students’ learning processes. These assignment often include the use of anatomical figures in atlases. The role of augmented reality (AR) applications in helping...

Background Imaging techniques play a central role in modern medicine and therefore it would be beneficial for all medical students to incorporate radiology education in medical school curricula. However, a formal undergraduate radiology curriculum with well-defined learning objectives remains lacking in The Netherlands. This study aims to qualitati...

Background It is difficult to distinguish between tumor progression (TP) and treatment-related abnormalities (TRA) in treated glioblastoma patients via conventional MRI, but this distinction is crucial for treatment decision making. Glioblastoma is known to exhibit an invasive growth pattern along white matter architecture and vasculature. This stu...

Visuospatial ability plays a crucial role in anatomy related study success as studies have shown that students with high scores on a mental rotation test (MRT) perform better on anatomy exams. We hypothesized that segmenting anatomical structures on radiological images might impact students’ visuospatial abilities as measured by MRT scores. Second-...

Introduction Dynamic susceptibility contrast (DSC) perfusion weighted (PW)-MRI can aid in differentiating treatment related abnormalities (TRA) from tumor progression (TP) in post-treatment glioma patients. Common methods, like the ‘hot spot’, or visual approach suffer from oversimplification and subjectivity. Using perfusion of the complete lesion...

Background Modern medicine becomes more dependent on radiologic imaging techniques. Over the past decade, radiology has also gained more attention in the medical curricula. However, little is known with regard to students’ perspectives on this subject. Therefore, this study aims to gain insight into the thoughts and ideas of medical students and ju...

Background Functional anatomical research proposed the existence of a bilateral trigeminal ascending system although the anatomy trajectories of the trigeminothalamic connections cranial to the pons remain largely elusive. This study therefore aimed to clarify the anatomical distributions of the trigeminothalamic connections in humans. Methods Adv...

ABSTRACT The role of molecular imaging with positron emission tomography (PET) for diagnosis, treatment planning and post-treatment monitoring of brain tumors has grown substantially in the last decades. In the last 25 years, almost 50 different PET agents have been developed and tested in human clinical studies. While some of these PET agents are...

Background Survival outcomes for glioblastoma (GBM) patients remain unfavorable, and tumor recurrence is often observed. Understanding the radiological growth patterns of GBM could aid in improving outcome. This study aimed to examine the relationship between contrast-enhancing tumor growth direction and white matter, using an image registration an...

Simple Summary Patients suffering from glioblastoma receive treatment according to the Stupp protocol. After chemoradiotherapy, the glioblastoma either continue to develop, or treatment-related vascular damage comes into play, both causing new, seemingly identical contrast-enhancing lesions in follow-up MRI, where clinicians and radiologists alike...

Introduction: Chronic pain after spinal surgery (CPSS), formerly known as failed back surgery syndrome, encompasses a variety of highly incapacitating chronic pain syndromes emerging after spinal surgery. The intractability of CPSS makes objective parameters that could aid classification and treatment essential. In this study, we investigated the...

Upregulation of prostate-specific membrane antigen (PSMA) in neovasculature has been described in glioblastoma multiforme (GBM), whereas vasculature in nonaffected brain shows hardly any expression of PSMA. It is unclear whether PSMA-targeting tracer uptake on PET is based on PSMA-specific binding to neovasculature or aspecific uptake in tumor. Her...

Objectives: The goal of this project is to explore the views, expectations and preferences of patients with an unruptured intracranial aneurysm regarding the use of AR in patient education. Methods: To gain an in-depth understanding of the patients’ perspective, a face-to-face interview study was conducted using an interview protocol with a predefi...

Although an increased usage and development of 3D technologies is observed in healthcare over the last decades, full integration of these technologies remains challenging. The goal of this project is to qualitatively explore challenges, pearls, and pitfalls of AR/VR/3D printing applications usage in the medical field of a university medical center....

Simple Summary This meta-analysis provides a first head-to-head comparison of PET and perfusion weighted magnetic resonance imaging (PWI) in the surveillance of post-treatment gliomas in order to distinguish tumor progression (TP) from treatment-related abnormalities (TRA). Although various reviews have been published on the use of either PET or PW...

Spinal cord stimulation (SCS) is a recommended therapy to treat failed back surgery syndrome (FBSS). A trial period is practised to enhance patient selection. However, its fundamental evidence is limited, especially concerning long-term benefit and therapy safety. We compared the long-term (5.3 ± 4.0 years) clinical outcome and therapy safety of a...

The aim of this study was to develop a magnetic resonance imaging (MRI) based radiomics model to predict mitosis cycles in intracranial meningioma grading prior to surgery. Preoperative contrast-enhanced T1-weighted (T1CE) cerebral MRI data of 167 meningioma patients between 2015 and 2020 were obtained, preprocessed and segmented using the 3D Slice...

Background Molecular characterization plays a crucial role in glioma classification which impacts treatment strategy and patient outcome. Dynamic susceptibility contrast (DSC) and dynamic contrast enhanced (DCE) perfusion imaging have been suggested as methods to help characterize glioma in a non-invasive fashion. This study set out to review and m...

Background In neuro-oncology, dynamic susceptibility contrast magnetic resonance (DSC-MR) perfusion imaging emerged as a tool to aid in the diagnostic work-up and to surveil effectiveness of treatment. However, it is believed that a significant variability exists with regard to the measured in DSC-MR perfusion parameters. The aim of this study was...

Background Failed back surgery syndrome (FBSS) is an umbrella term referring to painful sensations experienced by patients after spinal surgery, mostly of neuropathic nature. Adequate treatment of FBSS is challenging, as its etiology is believed to be multifactorial and still not fully clarified. Accurate identification of the source of pain is dif...

Background In a considerable subgroup of glioma patients treated with (chemo) radiation new lesions develop either representing tumor progression (TP) or treatment-related abnormalities (TRA). Quantitative diffusion imaging metrics such as the Apparent Diffusion Coefficient (ADC) and Fractional Anisotropy (FA) have been reported as potential metric...

Glioblastoma is the most aggressive of glial tumours in adults. On conventional magnetic resonance (MR) imaging, these tumours are observed as irregular enhancing lesions with areas of infiltrating tumour and cortical expansion. More advanced imaging techniques including diffusion weighted MRI, perfusion weighted MRI, MR spectroscopy and positron-e...

Our aim is to predict possible gross total and subtotal resections of skull meningiomas from pre-treatment T1 post contrast MR-images using radiomics and machine learning in a representative patient cohort. We analyse the accuracy of our model predictions depending on the tumor location within the skull and the postoperative tumor volume. In this r...

To investigate the applicability and performance of automated machine learning (AutoML) for potential applications in diagnostic neuroradiology. In the medical sector, there is a rapidly growing demand for machine learning methods, but only a limited number of corresponding experts. The comparatively simple handling of AutoML should enable even non...

Objective Our aim is to define the capabilities of radiomics in predicting pseudoprogression from pre-treatment MR images in patients diagnosed with high-grade gliomas using T1 non-contrast-enhanced and contrast-enhanced images. Material & Methods In this retrospective IRB-approved study, image segmentation of high-grade gliomas was semi-automatic...

Our aim is to define the capabilities of radiomics and machine learning in predicting pseudoprogression development from pre-treatment MR images in a patient cohort diagnosed with high grade gliomas. In this retrospective analysis, we analysed 131 patients with high grade gliomas. Segmentation of the contrast enhancing parts of the tumor before adm...

Objective: The primary objective of this anatomical study was to apply innovative imaging techniques to increase understanding of the microanatomical structures of the brainstem related to safe entry zones. The authors hypothesized that such a high-detail overview would enhance neurosurgeons' abilities to approach and define anatomical safe entry...

Objectives To provide an overview of the existing research concerning the use and effects of AR in patient education. Methods Following PRISMA guidelines four electronic databases were systematically searched. Inclusion criteria: empirical studies using any type of AR intervention in patient education across all medical specialties. Quality assess...

Background Spinal cord stimulation (SCS) is an established therapy of failed back surgery syndrome (FBSS), although the effects on daily functioning, quality of life (QoL), and patients’ expectations, experiences, and satisfaction remain elusive. The current integrative review aimed to summarize the overall effects of SCS in patients with FBSS on p...

Introduction Spinal cord stimulation (SCS) to treat failed back surgery syndrome (FBSS) can be provided with either percutaneously or surgically implanted electrodes. Percutaneous electrodes are considered the first choice in many pain practices, but surgical paddle electrodes can also be indicated if a percutaneous electrode fails to retain suffic...

The use of augmented reality (AR) in teaching and studying neuroanatomy has been well researched. Previous research showed that AR‐based learning of neuroanatomy has both alleviated cognitive load and was attractive to young learners. However, how the attractiveness of AR effects student motivation has not been discovered. Therefore, the motivation...

The use of Augmented Reality (AR) in anatomical education has been promoted by numerous authors. Next to financial and ethical advantages, AR has been described to decrease cognitive load while increasing student motivation and engagement. Despite these advantages, the effects of AR on learning outcome varies in different studies and an overview an...

Chronic migraine (CM) is a disabling neurologic disorder that affects approximately 2% of the general population. Neuroimaging studies show functional involvement of trigeminal structures, such as the trigeminal spinal nucleus (Sp5) in migraine. However, structural changes in the Sp5 and the afferent trigeminal spinal tract (sp5) have never been fo...

Neuroanatomy as a subject is important to learn, because a good understanding of neuroanatomy supports the establishment of a correct diagnosis in neurological patients. However, rapid changes in curricula reduced time assigned to study (neuro)anatomy. Therefore, it is important to find alternative teaching methods to study the complex three-dimens...

The genetic etiology of intellectual disability remains elusive in almost half of all affected individuals. Within the Solve-RD consortium, systematic re-analysis of whole exome sequencing (WES) data from unresolved cases with (syndromic) intellectual disability ( n = 1,472 probands) was performed. This re-analysis included variant calling of mitoc...

Treatment planning and prognosis in glioma treatment are based on the classification into low- and high-grade oligodendroglioma or astrocytoma, which is mainly based on molecular characteristics (IDH1/2- and 1p/19q codeletion status). It would be of great value if this classification could be made reliably before surgery, without biopsy. Machine le...

Objectives Different machine learning algorithms (MLAs) for automated segmentation of gliomas have been reported in the literature. Automated segmentation of different tumor characteristics can be of added value for the diagnostic work-up and treatment planning. The purpose of this study was to provide an overview and meta-analysis of different MLA...

Background Chronic pain is a major healthcare issue that often requires an interdisciplinary treatment approach. Defining relevant treatment goals is one of the crucial steps in creating successful rehabilitation schemes. Therefore, the first aim is to explore goals that patients suffering from chronic pain aim to achieve. The second aim is to tran...

Polarized light imaging (PLI) is a new method which quantifies and visualizes nerve fiber direction. In this study, the educational value of PLI sections of the human brainstem were compared to histological sections stained with Luxol fast blue (LFB) using e‐learning modules. Mental Rotations Test (MRT) was used to assess the spatial ability. Pre‐i...

Background: Predicting outcome after aneurysmal subarachnoid hemorrhage (aSAH) is known to be challenging and complex. Machine learning approaches, of which feedforward artificial neural networks (ffANNs) are the most widely used, could contribute to the patient-specific outcome prediction. Objective: To investigate the prediction capacity of an...

The use of Augmented Reality (AR) in anatomical education has been promoted by numerous authors. Next to financial and ethical advantages, AR has been described to decrease cognitive load while increasing student motivation and engagement. Despite these advantages, the effects of AR on learning outcome varies in different studies and an overview an...

Background The clinical outcomes of Spinal Cord Stimulation (SCS) therapy in patients with a Failed Back Surgery Syndrome (FBSS) is mostly done by standardized pain and quality of life measurements instruments and hardly account for personal feelings and needs as a basis for a patient-centred approach and shared decision making. Objectives The obj...

Introduction: When neither pharmacological therapies nor alternative interventions provide sufficient pain relief, spinal cord stimulation (SCS) can be used to treat Failed Back Surgery Syndrome (FBSS). Although it seems reasonable that quality of life (QoL)- and psychosocial-related factors contribute to the outcome of SCS since pain is a multidi...

Introduction: Recently, an additional trigeminothalamic tract - the dorsal trigeminothalamic tract - has been described in human brainstems by our group next to the known ventral trigeminothalamic tract. As various elements of the trigeminal system are known to be organised in a somatotopic fashion, the question arose whether the fibres within the...

Invasive motor Cortex Stimulation (iMCS) was introduced in the 1990’s for the treatment of chronic neuropathic orofacial pain (CNOP), although its effectiveness remains doubtful. However, CNOP is known to be a heterogeneous group of orofacial pain disorders, which can lead to different responses to iMCS. Therefore, this paper investigated (1) wheth...

The above article was published online with incorrect spelling of author name. The published online paper states "Frederik Meijer", whereas it should be "Frederick Meijer". The surname has been corrected above. The original article has been corrected.

Objective: Invasive motor cortex stimulation (iMCS) has been proposed as a treatment for intractable neuropathic pain syndromes. Although the mechanisms underlying the analgesic effect of iMCS remain largely elusive, several studies found iMCS-related changes in regional cerebral blood flow (rCBF) in neuropathic pain patients. The aim of this stud...

Background: Various studies reported changes in grey matter volumes and modifications in functional connectivity of cortical and subcortical structures in patients suffering from trigeminal neuralgia (TN) and trigeminal neuropathic pain (TNP). This study meta-analyzed the concordant structural and functional changes in foci and provide further und...

Experimental treatments for treating neuropathic pain include transcranial magnetic stimulation (TMS) and invasive electric motor cortex stimulation (iMCS) of the primary motor cortex (M1). Mechanisms of action of both methods, however, remain largely elusive. Within this paper, we focus on animal-based experiments in order to investigate the biolo...

A trigeminovagal complex, as described in some animals, could help to explain the effect of vagus nerve stimulation as a treatment for headache disorders. However, the existence of a trigeminovagal complex in humans remains unclear. This study, therefore investigated the existence of the trigeminovagal complex in humans. One post-mortem human brain...

Neuroanatomy education is a challenging field which could benefit from modern innovations, such as augmented reality (AR) applications. This study investigates the differences on test scores, cognitive load, and motivation after neuroanatomy learning using AR applications or using cross‐sections of the brain. Prior to two practical assignments, a p...

Background: Destruction of the afferents by dorsal root entry zone (DREZ) surgery may be an effective treatment of intractable neuropathic pain, though it remains a high-risk surgical intervention. Potential complications due to the lesioning of structures within the cervical spinal cord other than the DREZ can be minimized by accurate knowledge of...

Background: Non-invasive stimulation of the vagus nerve has been proposed as a new neuromodulation therapy to treat primary headache disorders, as the vagus nerve is hypothesized to modulate the headache pain pathways in the brain. Vagus nerve stimulation can be performed by placing an electrode on the ear to stimulate the tragus nerve, which cont...

Background The pedunculopontine nucleus (PPN) has been studied as a possible target for deep brain stimulation (DBS) for Parkinson’s disease (PD). However, identifying the PPN can be challenging as the PPN is poorly visualized on conventional or even high-resolution MR scans. From histological studies it is known that the PPN is surrounded by major...

Implantable motor cortex stimulation (iMCS) has been performed for >25 years to treat various intractable pain syndromes. Its effectiveness is highly variable and, although various studies revealed predictive variables, none of these were found repeatedly. This study uses neural network analysis (NNA) to identify predictive factors of iMCS treatmen...

In this Letter, we describe the organisation and recommendations of the first neurosurgery summer event for and by students. The main purpose of the event was to meet the demand for neurosurgical education and promote academic networks. Students collaborated with an academic neurosurgical centre to host the event. All involved experienced a positiv...

Classic anatomical atlases depict a contralateral hemispheral representation of each side of the face. Recently, however, a bilateral projection of each hemiface was hypothesized, based on animal studies that showed the coexistence of an additional trigeminothalamic tract sprouting from the trigeminal principal sensory nucleus that ascends ipsilate...

Background Motor cortex stimulation (MCS) was introduced as a last-resort treatment for chronic neuropathic pain. Over the years, MCS has been used for the treatment of various pain syndromes but long-term follow-up is unknown. Methods This paper reports the results of MCS from 2005 until 2012 with a 3-year follow-up. Patients who suffered from ch...

Clinical protocol in English. (PDF)

Anonymized database. (XLSX)

TREND statement checklist. The Transparent Reporting of Evaluations with Non-randomized Designs (TREND) group aimed to improve the reporting standards of non-randomized evaluations of behavioral and public health interventions. The TREND statement checklist is a 22-item checklist that was specifically developed to guide standardized reporting of no...

Clinical protocol in Dutch. (PDF)

Background: Motor Cortex Stimulation (MCS) was introduced in the early 1990's by Tsubokawa and his group for patients diagnosed with drug-resistant, central neuropathic pain. Inconsistencies concerning the details of this therapy and its outcomes and poor methodology of most clinical essays, divide the neuromodulation society worldwide in "believe...

Background: Spinal cord stimulation (SCS) is an effective therapy to reduce pain in patients that suffer from failed back surgery syndrome (FBSS). In order to inform patients optimally prior to this therapy, knowing their expectations is crucial. Methods: Thirteen patients suffering from FBSS and scheduled for SCS were interviewed, using a semi-...

To optimize neuromodulation therapy of orofacial pain, a more profound insight in the trigeminal pathways in the human brainstem is of crucial importance. Using ex-vivo, 11.7T magnetic resonance imaging, polarized light microscopy and myelin staining methods, both the ventral and dorsal trigeminothalamic tracts can be visualized in humans. The comb...

Orofacial pain in patients relies on the anatomical pathways conducting nociceptive information, originating from the periphery towards the trigeminal sensory nucleus complex (TSNC) and finally, to the grey matter structures located in the diencephalon and the somatosensorical cortical regions. The anatomy and function of the so-called trigeminotha...

Chronic intractable shoulder pain (CISP) is defined as shoulder pain which is present for longer than 6 months and does not respond to standard treatments like medication, physical therapy, rehabilitation, selective nerve blocks and local infiltrations, or orthopedic procedures. The etiology of CISP may be very diverse, varying from many orthopedic...