Making the Invisible Visible: Advanced Neuroimaging Techniques in Focal Epilepsy

It has been a clinically important, long-standing challenge to accurately localize epileptogenic focus in drug-resistant focal epilepsy because more intensive intervention to the detected focus, including resection neurosurgery, can provide significant seizure reduction. In addition to neurophysiological examinations, neuroimaging plays a crucial role in the detection of focus by providing morphological and neuroanatomical information. On the other hand, epileptogenic lesions in the brain may sometimes show only subtle or even invisible abnormalities on conventional MRI sequences, and thus, efforts have been made for better visualization and improved detection of the focus lesions. Recent advance in neuroimaging has been attracting attention because of the potentials to better visualize the epileptogenic lesions as well as provide novel information about the pathophysiology of epilepsy. While the progress of newer neuroimaging techniques, including the non-Gaussian diffusion model and arterial spin labeling, could non-invasively detect decreased neurite parameters or hypoperfusion within the focus lesions, advances in analytic technology may also provide usefulness for both focus detection and understanding of epilepsy. There has been an increasing number of clinical and experimental applications of machine learning and network analysis in the field of epilepsy. This review article will shed light on recent advances in neuroimaging for focal epilepsy, including both technical progress of images and newer analytical methodologies and discuss about the potential usefulness in clinical practice.

Long-term brain network reorganization predicts responsive neurostimulation outcomes for focal epilepsy

Science Translational Medicine ◽

10.1126/scitranslmed.abf6588 ◽

2021 ◽

Vol 13 (608) ◽

pp. eabf6588

Author(s):

Ankit N. Khambhati ◽

Alia Shafi ◽

Vikram R. Rao ◽

Edward F. Chang

Keyword(s):

Therapeutic Response ◽

Focal Epilepsy ◽

Therapeutic Benefit ◽

Brain Network ◽

First Year ◽

Seizure Reduction ◽

Neural Recordings ◽

Brain Network Reorganization ◽

Responsive neurostimulation (RNS) devices, able to detect imminent seizures and to rapidly deliver electrical stimulation to the brain, are effective in reducing seizures in some patients with focal epilepsy. However, therapeutic response to RNS is often slow, is highly variable, and defies prognostication based on clinical factors. A prevailing view holds that RNS efficacy is primarily mediated by acute seizure termination; yet, stimulations greatly outnumber seizures and occur mostly in the interictal state, suggesting chronic modulation of brain networks that generate seizures. Here, using years-long intracranial neural recordings collected during RNS therapy, we found that patients with the greatest therapeutic benefit undergo progressive, frequency-dependent reorganization of interictal functional connectivity. The extent of this reorganization scales directly with seizure reduction and emerges within the first year of RNS treatment, enabling potential early prediction of therapeutic response. Our findings reveal a mechanism for RNS that involves network plasticity and may inform development of next-generation devices for epilepsy.

Patch-based generation of a pseudo CT from conventional MRI sequences for MRI-only radiotherapy of the brain

Medical Physics ◽

10.1118/1.4914158 ◽

2015 ◽

Vol 42 (4) ◽

pp. 1596-1605 ◽

Cited By ~ 76

Author(s):

Daniel Andreasen ◽

Koen Van Leemput ◽

Rasmus H. Hansen ◽

Jon A. L. Andersen ◽

Jens M. Edmund

Keyword(s):

Conventional Mri ◽

Mri Sequences ◽

Quantitative MRI of the brain in children with sickle cell disease reveals abnormalities unseen by conventional MRI

Journal of Magnetic Resonance Imaging ◽

10.1002/jmri.1880080304 ◽

1998 ◽

Vol 8 (3) ◽

pp. 535-543 ◽

Cited By ~ 41

Author(s):

R. Grant Steen ◽

Wilburn E. Reddick ◽

Raymond K. Mulhern ◽

James W. Langston ◽

Robert J. Ogg ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Quantitative Mri ◽

Cell Disease ◽

Conventional Mri ◽

Pain Detection and the Privacy of Subjective Experience

American Journal of Law & Medicine ◽

10.1177/009885880703300212 ◽

2007 ◽

Vol 33 (2-3) ◽

pp. 433-456 ◽

Cited By ~ 22

Author(s):

Adam J. Kolber

Keyword(s):

Subjective Experience ◽

Brain Regions ◽

Physical Pain ◽

Medical Evidence ◽

Functional Magnetic Resonance ◽

Positron Emission ◽

Pain Symptoms ◽

The Brain ◽

Insight Into ◽

A neurologist with abdominal pain goes to see a gastroenterologist for treatment. The gastroenterologist asks the neurologist where it hurts. The neurologist replies, “In my head, of course.” Indeed, while we can feel pain throughout much of our bodies, pain signals undergo most of their processing in the brain. Using neuroimaging techniques like functional magnetic resonance imaging (“fMRI”) and positron emission tomography (“PET”), researchers have more precisely identified brain regions that enable us to experience physical pain. Certain regions of the brain's cortex, for example, increase in activation when subjects are exposed to painful stimuli. Furthermore, the amount of activation increases with the intensity of the painful stimulus. These findings suggest that we may be able to gain insight into the amount of pain a particular person is experiencing by non-invasively imaging his brain.Such insight could be particularly valuable in the courtroom where we often have no definitive medical evidence to prove or disprove claims about the existence and extent of pain symptoms.

ROLE OF DIFFUSION WEIGHTED MRI IN ASSESSMENT OF BENIGN AND MALIGNANT HEPATIC FOCAL LESIONS IN ADULT AGE GROUP

QJM ◽

10.1093/qjmed/hcab106.042 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Hanan Mohammed Hanafy ◽

Ayman Mohammed Ibrahim ◽

Haytham Mohamed Nasser ◽

Moataz Metwally Elsayed

Keyword(s):

Focal Lesions ◽

Adc Value ◽

Adult Age ◽

Conventional Mri ◽

Diffusion Weighted ◽

Adc Values ◽

Weighted Magnetic Resonance Imaging ◽

Mri Sequences ◽

Value Measurement

Abstract Purpose of this study is: To evaluate the role of diffusion weighted magnetic resonance imaging in differentiation between malignant & benign hepatic focal lesions. Methods The study included 38 patients all of them were with hepatic focal lesions detected by ultrasound (between 20 and 85 years of age) referred from GIT and oncology departments. Each patient included in the study was subjected to full history taking, ultrasonography and conventional MRI sequences, post Gd- DTPA dynamic and Diffusion Weighted imaging as well as ADC value measurement. Technique was performed using a standard 1.5 Tesla unit (Ingenia, Philips). Detailed MRI and laboratory investigations were done. Results The study showed significant results were obtained between ADC values of benign and malignant hepatic focal lesions (p < 0.001). Conclusion We concluded in this study according to the obtained results that DWI sequence together with quantitative ADC values should be used as an essential sequence to supplement the conventional MRI sequences for proper detection and characterization of hepatic focal lesions.

Neurocomics and Neuroimaging

The Elusive Brain ◽

10.12987/yale/9780300221176.003.0010 ◽

2018 ◽

Author(s):

Jason Tougaw

Keyword(s):

Brain Research ◽

Direct Access ◽

Brain Images ◽

High Profile ◽

Graphic Narratives ◽

Novel Methods ◽

The Aesthetic ◽

Cultural Responses ◽

The Brain ◽

This chapter examines a small number of recent graphic brain narratives that experiment with novel methods of visualizing the brain—including David B.’s Epileptic, Ellen Forney’s Marbles, and Matteo Farinella and Hana Ros’s Neurocomic. Tougaw argues that these narratives both draw from and challenge cultural responses to high-profile neuroimaging techniques, including PET and fMRI. Graphic narratives are a subcultural genre celebrated for their rebellious aesthetics and emphasis on narratives that challenge mainstream social and political assumptions. Brain scanning technologies are highly specialized tools that have revolutionized brain research and gained considerable mainstream attention. The mainstreaming of these technologies oversimplifies the images they produce, creating a widely held sense that they offer direct access to the brains they visualize. By contrast, graphic narratives put heavy emphasis on the aesthetic process involved in their making of brain images. While careful not to minimize these differences, the chapter argues that key similarities between neurocomics and neuroimaging techniques can be a means for clarifying the roles played by the sciences and the humanities in the cultural laboratory of contemporary neuromania.

Understanding Mental Health and Cognitive Restructuring With Ecological Neuroscience

Frontiers in Psychiatry ◽

10.3389/fpsyt.2021.697095 ◽

2021 ◽

Vol 12 ◽

Author(s):

James Crum

Keyword(s):

Mental Health ◽

Near Infrared ◽

Ecological Validity ◽

Experimental Designs ◽

Functional Near Infrared Spectroscopy ◽

Practical Applications ◽

Recent Developments ◽

The Brain ◽

Neuroimaging Techniques ◽

Selection Of

Neuroimaging and neuropsychological methods have contributed much toward an understanding of the information processing systems of the human brain in the last few decades, but to what extent do cognitive neuroscientific findings represent and generalize to the inter- and intra-brain dynamics engaged in adapting to naturalistic situations? If it is not marked, and experimental designs lack ecological validity, then this stands to potentially impact the practical applications of a paradigm. In no other domain is this more important to acknowledge than in human clinical neuroimaging research, wherein reduced ecological validity could mean a loss in clinical utility. One way to improve the generalizability and representativeness of findings is to adopt a more “real-world” approach to the development and selection of experimental designs and neuroimaging techniques to investigate the clinically-relevant phenomena of interest. For example, some relatively recent developments to neuroimaging techniques such as functional near-infrared spectroscopy (fNIRS) make it possible to create experimental designs using naturalistic tasks that would otherwise not be possible within the confines of a conventional laboratory. Mental health, cognitive interventions, and the present challenges to investigating the brain during treatment are discussed, as well as how the ecological use of fNIRS might be helpful in bridging the explanatory gaps to understanding the cultivation of mental health.

The Boundaries of Babel

Impossible Languages ◽

10.7551/mitpress/9780262034890.003.0005 ◽

2016 ◽

Cited By ~ 5

Author(s):

Andrea Moro

Keyword(s):

Hierarchical Structure ◽

Linear Order ◽

Neural Circuits ◽

Recursive Procedure ◽

The Brain ◽

One of the major discoveries of modern linguistics is that languages do not vary arbitrarily: for example, all syntactic rules must be based on hierarchical structure generated by recursive procedure rather than linear order. Neuroimaging techniques have shown that these formal restrictions constituting the boundaries of Babel are in fact represented in the brain for people who learn non-recursive artificially designed rules do not involve those neural circuits that underpin language computation. The boundaries of Babels cannot be cultural and arbitrary.

The Stories Stones Tell of Language and Its Evolution

Squeezing Minds From Stones ◽

10.1093/oso/9780190854614.003.0015 ◽

2019 ◽

pp. 304-318

Author(s):

Shelby S. Putt

Keyword(s):

Language Evolution ◽

Evolutionary Relationship ◽

Stone Tools ◽

Stone Tool ◽

Motor Tasks ◽

Activation Patterns ◽

Cognitive Operations ◽

Pars Opercularis ◽

The Brain ◽

Language origins remain shrouded in mystery. With little remaining from our earliest ancestors, language evolution researchers have turned to stone tools to learn about ancestral language capacities, as discussed in this chapter. Because inferior frontal areas of the brain, once thought specific to language, are now known to participate during manual motor tasks as well, technological-origin hypotheses propose that tool-making was a potential cause or contributor to the evolution of language. Cutting-edge neuroimaging techniques to monitor regional brain activation patterns associated with tool-making processes are helping to investigate the potential evolutionary relationship between language and tool-making. These experiments have identified one area in the left dorsal pars opercularis portion of Broca’s area where language and stone tool-making functions rely on similar cognitive operations. A more general motor origin for language seems likely in other inferior frontal areas of the brain. Clearly, stone tools have stories to tell if we know how to listen.

Classification of seizures and epilepsy

Oxford Textbook of Neurological Surgery ◽

10.1093/med/9780198746706.003.0081 ◽

2019 ◽

pp. 935-944

Author(s):

Andrew McEvoy ◽

Tim Wehner ◽

Victoria Wykes

Keyword(s):

Focal Epilepsy ◽

Focal Cortical Dysplasia ◽

Hippocampal Sclerosis ◽

Epileptic Seizures ◽

Recurrence Risk ◽

Medical Emergency ◽

Unprovoked Seizure ◽

Generalized Seizures ◽

Epileptic seizures are transient neurologic alterations due to abnormal excessive or synchronous neuronal cerebral activity. They may cause subjective symptoms (aura), and objective autonomic, behavioural, or cognitive alterations in any combination. Focal seizures are initially generated in one circumscribed area in the brain, whereas generalized seizures involve bihemispheric neuronal networks from the seizure onset. Epilepsy is a brain disease defined by the occurrence of two unprovoked seizures more than 24 h apart or one unprovoked seizure with underlying pathological or genetic factors resulting in a similar recurrence risk. Focal epilepsy syndromes are best classified by aetiology or anatomical area of origin. A seizure that does not self-terminate results in status epilepticus, and constitutes a medical emergency that requires immediate treatment. Focal cortical dysplasia and hippocampal sclerosis are the commonest aetiologies of epilepsy amenable to surgical treatment and are reviewed here. The limbic pathway may be involved in seizure propagation, and the anatomy is described.