Surgery of the mind, mood, and conscious state: an idea in evolution

Quantum Computing in the Realm of Neurosurgery

Quantum computing leverages the principles of quantum mechanics to provide unprecedented computational power by processing data in a fundamentally different way from classical binary computers. Quantum computers use "qubits" which superimpose 0 and 1. Because qubits can exist in multiple states at the same time, quantum computers can perform "quantum parallelism" wherein data are processed simultaneously rather than sequentially. The quantum parallelism is what enables the computer to have exponentially larger processing capabilities and consider all potential outcomes simultaneously to derive solutions. Our study aims to explore aspects of neurosurgery through which quantum computing could improve patient outcomes and enhance quality of care. Quantum computing has the potential for future applications in neuroprosthetics, neurostimulation, surgical precision, diagnosis, and patient privacy and security. It promises improved patient outcomes, enhanced surgical precision, and personalized healthcare delivery. With its inherent sensitivity and precision, quantum computing could advance the understanding of disease processes and development, providing neurosurgeons with deeper insight into patient pathologies. Challenges such as biocompatibility, cost, and ethical considerations remain significant barriers to integrating the technology into neurosurgical practice. Addressing these challenges will be crucial for realizing the transformative potential of quantum computing in advancing neurosurgical care and improving clinical outcomes.

The role of MRgFUS in the treatment of neuropsychiatric disorders: a state of the art

INTRODUCTION

Magnetic resonance-guided focused ultrasound (MRgFUS) is a contemporary non-invasive ablative procedure that utilizes high- or low-intensity ultrasound, guided and monitored by magnetic resonance imaging (MRI). While MRgFUS has been established as an effective treatment for conditions like essential tremor and tremor-dominant Parkinson's disease, it has recently emerged as a safe and promising ablative minimally invasive procedure for the management of treatment-resistant psychiatric disorders. Indeed, despite the availability of various pharmacological and behavioral therapies, a subset of psychiatric patients remains refractory to conventional treatments.

EVIDENCE ACQUISITION

To assess the feasibility and safety of MRgFUS in psychiatric disorders, a comprehensive literature search in PubMed and Scopus databases was conducted, resulting in the inclusion of five relevant articles in this review.

EVIDENCE SYNTHESIS

While data on this innovative procedure are still limited, MRgFUS demonstrates potential as a safer and less invasive surgical technique for treating these disorders.

CONCLUSIONS

Continued research efforts and data validation are imperative to establish MRgFUS as an additional, minimally invasive procedure for treatment-resistant psychiatric patients in the near future.

The neurobiology of functional neurological disorders characterised by impaired awareness

We review the neurobiology of Functional Neurological Disorders (FND), i.e., neurological disorders not explained by currently identifiable histopathological processes, in order to focus on those characterised by impaired awareness (functionally impaired awareness disorders, FIAD), and especially, on the paradigmatic case of Resignation Syndrome (RS). We thus provide an improved more integrated theory of FIAD, able to guide both research priorities and the diagnostic formulation of FIAD. We systematically address the diverse spectrum of clinical presentations of FND with impaired awareness, and offer a new framework for understanding FIAD. We find that unraveling the historical development of neurobiological theory of FIAD is of paramount importance for its current understanding. Then, we integrate contemporary clinical material in order to contextualise the neurobiology of FIAD within social, cultural, and psychological perspectives. We thus review neuro-computational insights in FND in general, to arrive at a more coherent account of FIAD. FIAD may be based on maladaptive predictive coding, shaped by stress, attention, uncertainty, and, ultimately, neurally encoded beliefs and their updates. We also critically appraise arguments in support of and against such Bayesian models. Finally, we discuss implications of our theoretical account and provide pointers towards an improved clinical diagnostic formulation of FIAD. We suggest directions for future research towards a more unified theory on which future interventions and management strategies could be based, as effective treatments and clinical trial evidence remain limited.

Gamma Knife capsulotomy for correction of obsessive-compulsive symptoms in a patient with schizophrenia: Case report

The treatment of mental illnesses that are resistant to conservative therapy poses a serious problem. Surgical methods with proven efficacy have been proposed for only a small group of psychiatric diseases, while in practice non-classical clinical situations are seen rather often. A 36-year-old man with a 18-year history of "schizophrenia with a predominant obsessive-compulsive syndrome" was referred to the Burdenko National Medical Research Center of Neurosurgery for consideration of neurosurgical treatment. Based on results of longitudinal independent evaluations of the patient in several specialized clinical centers the disease was considered resistant to medical therapy. Radiosurgical procedure was performed by means of Leksell Gamma Knife Perfexion™ (Elekta AB; Stockholm, Sweden). Ventral portion of the anterior limb of internal capsule was targeted with two 4-mm isocenters on each side, with prescription dose at 50% isodose line of 80 Gy and a maximal dose of 160 Gy. No obvious complications or side effects were noted during 13-month follow-up after radiosurgery. Gradual clinical improvement was observed with 25% reduction of the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score at 13 months after treatment. Similarly, the Hospital Anxiety and Depression Scale (HADS) anxiety and depression scores decreased by 24% and 58%, respectively. This is the first published case of radiosurgical treatment of a psychiatric disorder in Russia. It demonstrates the potential efficacy of Gamma Knife capsulotomy for non-classical forms of obsessive-compulsive disorder comorbid with schizophrenia. Nevertheless, definitive conclusions about the reliability of this radiosurgical indication can only be made based on the results of larger studies.

Barriers and facilitators in the implementation of a telemedicine-based outpatient brain tumor surgery program

OBJECTIVE

Despite growing evidence on the benefits of outpatient oncological neurosurgery (OON), it is only performed in a few specialized centers and there are no previous descriptions of established OON programs in Europe. Moreover, increasing application of telemedicine strategies, especially after the start of the coronavirus disease 2019 (COVID-19) pandemic, is drastically changing neurosurgical management, particularly in the case of vulnerable populations such as neuro-oncological patients. In this context, the authors implemented an OON program in their hospital with telematic follow-up. Herein, they describe the protocol and qualitatively analyze the barriers and facilitators of the development process.

METHODS

An OON program was developed through the following steps: assessment of hospital needs, specific OON training, multidisciplinary team organization, and OON protocol design. In addition, the implementation phase included training sessions, a pilot study, and continuous improvement sessions. Finally, barriers and facilitators of the protocol’s implementation were identified from the feedback of all participants.

RESULTS

An OON protocol was successfully designed and implemented for resection or biopsy of supratentorial lesions up to 3 cm in diameter. The protocol included the patient’s admission to the day surgery unit, noninvasive anesthetic monitoring, same-day discharge, and admission to the hospital-at-home (HaH) unit for telematic and on-site postoperative care. After a pilot study including 10 procedures in 9 patients, the main barriers identified were healthcare provider resistance to change, lack of experience in outpatient neurosurgery, patient reluctance, and limitations in the recruitment of patients. Key facilitators of the process were the patient education program, the multidisciplinary team approach, and the HaH-based telematic postoperative care.

CONCLUSIONS

Initiating an OON program with telematic follow-up in a European clinical setting is feasible. Nevertheless, it poses several barriers that can be overcome by identifying and maximizing key facilitators of the process. Among them, patient education, a multidisciplinary team approach, and HaH-based postoperative care were crucial to the success of the program. Future studies should investigate the cost-effectiveness of telemedicine to assess potential cost savings, from reduced travel and wait times, and the impact on patient satisfaction.

Modern neurosurgical techniques for psychiatric disorders

Psychosurgery refers to an ensemble of more or less invasive techniques designed to reduce the burden caused by psychiatric diseases in patients who have failed to respond to conventional therapy. While most surgeries are designed to correct apparent anatomical abnormalities, no discrete cerebral anatomical lesion is evident in most psychiatric diseases amenable to invasive interventions. Finding the optimal surgical targets in mental illness is troublesome. In general, contemporary psychosurgical procedures can be classified into one of two primary modalities: lesioning and stimulation procedures. The first group is divided into (a) thermocoagulation and (b) stereotactic radiosurgery or recently introduced transcranial magnetic resonance-guided focused ultrasound, whereas stimulation techniques mainly include deep brain stimulation (DBS), cortical stimulation, and the vagus nerve stimulation. The most studied psychiatric diseases amenable to psychosurgical interventions are severe treatment-resistant major depressive disorder, obsessive-compulsive disorder, Tourette syndrome, anorexia nervosa, schizophrenia, and substance use disorder. Furthermore, modern neuroimaging techniques spurred the interest of clinicians to identify cerebral regions amenable to be manipulated to control psychiatric symptoms. On this way, the concept of a multi-nodal network need to be embraced, enticing the collaboration of psychiatrists, psychologists, neurologists and neurosurgeons participating in multidisciplinary groups, conducting well-designed clinical trials.

Deep Brain Stimulation for Intractable Obsessive-Compulsive Disorder and Treatment-Resistant Depression

In deep brain stimulation (DBS), a neurostimulation device is implanted to generate electrical fields in targeted deep brain regions in order to affect circuits associated with neuropsychiatric illness for potential therapeutic benefit. The development of DBS has followed a decades-long history of psychiatric neurosurgery, with advances in pacemakers and spinal neurostimulation devices allowing for the use of DBS in the treatment of neuropsychiatric disorders. Currently, deep brain stimulation for psychiatric illness has been approved by the U.S. Food and Drug Administration for the treatment of intractable obsessive-compulsive disorder, through a Humanitarian Device Exemption. The use of DBS for treatment-resistant depression is another promising application of this technology. Several potential targets of DBS have shown promise for treating neuropsychiatric illness, but few have demonstrated efficacy in randomized controlled trials. Future directions for DBS research will likely include modified trial designs, refined targets, the use of tractography for more specific and individualized targeting, and development of closed-loop DBS.

From vision to action: Canadian leadership in ethics and neurotechnology

This chapter explores the complex neuroethical aspects of neurosurgery and neuromodulation in the context of Canadian healthcare and innovation, as seen through the lens of the Pan Canadian Neurotechnology Ethics Consortium (PCNEC). Highlighted are key areas of ethical focus, each with its own unique challenges: technical advances, readiness and risk, vulnerable populations, medico-legal issues, training, and research. Through an exploration of Canadian neurotechnological practice from these various clusters, we provide a critical review of progress, describe opportunities to address areas of debate, and seek to foster ethical innovation. Underpinning this comprehensive review are the fundamental principles of solution-oriented, practical neuroethics, with beneficence and justice at the core. In our view, it is a moral imperative that neurotechnological advancements include a delineation of ethical priorities for future guidelines, oversight, and interactions.

International Legal Approaches to Neurosurgery for Psychiatric Disorders

Neurosurgery for psychiatric disorders (NPD), also sometimes referred to as psychosurgery, is rapidly evolving, with new techniques and indications being investigated actively. Many within the field have suggested that some form of guidelines or regulations are needed to help ensure that a promising field develops safely. Multiple countries have enacted specific laws regulating NPD. This article reviews NPD-specific laws drawn from North and South America, Asia and Europe, in order to identify the typical form and contents of these laws and to set the groundwork for the design of an optimal regulation for the field. Key challenges for this design that are revealed by the review are how to define the scope of the law (what should be regulated), what types of regulations are required (eligibility criteria, approval procedures, data collection, and oversight mechanisms), and how to approach international harmonization given the potential migration of researchers and patients.

The Proud History of Psychosurgery in the USA

To understand the development and growth of psychosurgery, the context of psychiatric care in the mid-twentieth-century USA must be considered-for example, overpopulation and understaffing of public institutions, and typical use of psychotherapy, which was generally useless in treating the symptomatology of severe mental illness. Therefore, the introduction of prefrontal lobotomy (and, later, transorbital lobotomy) by Drs. Walter Freeman and James Watts, who modified the technique of leukotomy developed by Nobel Prize laureate Dr. Egas Moniz, was considered revolutionary and quickly gained widespread acceptance by medical community. No other alternative treatment at the time demonstrated comparable efficacy. At its peak, psychosurgery was sometimes applied inappropriately, but records from multiple institutions across the USA demonstrate that these were exceptional cases, whereas, as a rule, selection of surgical candidates was based on very strict criteria, indicating the high professionalism and humanity of medical staff. Although psychosurgery has declined heavily since the 1950s, it is not obsolete and is currently considered a valuable treatment option, realized through various open, stereotactic, or radiosurgical procedures.

Deep brain stimulation in the treatment of obsessive-compulsive disorder: current perspectives

Deep brain stimulation (DBS) is a neuro-psychosurgical technique widely accepted in movement disorders, such as Parkinson's disease. Since 1999, DBS has been explored for severe, chronic and treatment-refractory psychiatric diseases. Our review focuses on DBS in obsessive-compulsive disorder (OCD), considered as a last treatment resort by most of learned societies in psychiatry. Two main stimulation areas have been studied: the striatal region and the subthalamic nucleus. But, most of the trials are open-labeled, and the rare controlled ones have failed to highlight the most efficient target. The recent perspectives are otherwise encouraging. Indeed, clinicians are currently considering other promising targets. A case series of 2 patients reported a decrease in OCD symptoms after DBS in the medial forebrain bundle and an open-label study is exploring bilateral habenula stimulation. New response criteria are also investigating such as quality of life, or subjective and lived-experience. Moreover, first papers about cost-effectiveness which is an important criterion in decision making, have been published. The effectiveness of tractography-assisted DBS or micro-assisted DBS is studying with the aim to improve targeting precision. In addition, a trial involving rechargeable pacemakers is undergoing because this mechanism could be efficient and have a positive impact on cost-effectiveness. A recent trial has discussed the possibility of using combined cognitive behavioral therapy (CBT) and DBS as an augmentation strategy. Finally, based on RDoc Research, the latest hypotheses about the understanding of cortico-striato-thalamo-cortical circuits could offer new directions including clinical predictors and biomarkers to perform adaptive closed-loop systems in the next future.

Ablative stereotactic neurosurgery for irreducible neuroaggressive disorder in pediatric patients

INTRODUCTION AND OBJECTIVES

The irreducible neuroaggressive disorder (IND) is a well-described entity known to be associated with impulsive and aggressive behavior. While various studies have assessed available pharmacological and non-pharmacological treatment regimens, patients with IND continue to pose a major threat to themselves and society. While targeted stereotactic therapy for IND has gained traction in recent years, there is a paucity of information describing comparative effectiveness of different validated anatomic regions. In this paper, we discuss the surgical results for patients with IND following targeted lesional therapy with a special focus on selection criteria and operative methods. The objective is to analyze the efficacy and safety of the different described targets for this disorder in pediatric patients.

MATERIALS AND METHODS

Eight pediatric patients met strict criteria for IND and were enrolled in this study. Electroencephalography (EEG), video electroencephalography (VEEG) and magnetic resonance imaging (MRI) were performed in all patients prior to surgery. Irreducible neuroagressive symptom was approached by lesional therapy based on most described targets for this disorder and assessed by The Overt Agressive Scale (OAS) pre-operatively and 6 months following surgery, using Wilcoxon test for statistical analysis.

RESULTS AND CONCLUSIONS

The average patient age was 13 years 2 months. 7 of the 8 patients enrolled had intellectual disabilities, 1 patient suffered neurologic sequelae referable to Dandy Walker syndrome and 7 patients had no preoperative anatomical alterations. Following surgery, patients with IND noted improvement in their OAS. On average, the OAS improved by 39.29% (P=.0156), a figure similar in comparison to studies assessing treatment of IND in adult patients. The most satisfactory results were achieved in patients whose ablative therapy involved the Amygdala in their targets. There were no deaths or permanent neurological deficits attributable to procedure. To the author's knowledge, this is the largest series described in the literature for pediatric patients with IND treated with lesional stereotactic therapy.

Post-lobotomy epilepsy illustrated by the story of Ellinor Hamsun, the daughter of the famous Norwegian author Knut Hamsun

In Scandinavia, at least 11.500 people were lobotomized in the period 1939–1983. Beside grave personality changes, the surgery caused epilepsy in 10–35% of the patients. Moreover, many died due to perioperative bleedings, convulsive status epilepticus or SUDEP.

Most of the stories of these people are anonymous and their post-lobotomy lives are scarcely documented. If it was not for the fact that Ellinor Hamsun (1916–1987) was the daughter of the famous Nobel Prize winning Norwegian author Knut Hamsun, her lobotomy story and the subsequent iatrogenic epilepsy would probably have remained unknown.

History of psychosurgery at Sainte-Anne Hospital, Paris, France, through translational interactions between psychiatrists and neurosurgeons

Sainte-Anne Hospital is the largest psychiatric hospital in Paris. Its long and fascinating history began in the 18th century. In 1952, it was at Sainte-Anne Hospital that Jean Delay and Pierre Deniker used the first neuroleptic, chlorpromazine, to cure psychiatric patients, putting an end to the expansion of psychosurgery. The Department of Neuro-psychosurgery was created in 1941. The works of successive heads of the Neurosurgery Department at Sainte-Anne Hospital summarized the history of psychosurgery in France.

Pierre Puech defined psychosurgery as the necessary cooperation between neurosurgeons and psychiatrists to treat the conditions causing psychiatric symptoms, from brain tumors to mental health disorders. He reported the results of his series of 369 cases and underlined the necessity for proper follow-up and postoperative re-education, illustrating the relative caution of French neurosurgeons concerning psychosurgery.

Marcel David and his assistants tried to follow their patients closely postoperatively; this resulted in numerous publications with significant follow-up and conclusions. As early as 1955, David reported intellectual degradation 2 years after prefrontal leucotomies.

Jean Talairach, a psychiatrist who eventually trained as a neurosurgeon, was the first to describe anterior capsulotomy in 1949. He operated in several hospitals outside of Paris, including the Sarthe Psychiatric Hospital and the Public Institution of Mental Health in the Lille region. He developed stereotactic surgery, notably stereo-electroencephalography, for epilepsy surgery but also to treat psychiatric patients using stereotactic lesioning with radiofrequency ablation or radioactive seeds of yttrium-90.

The evolution of functional neurosurgery has been marked by the development of deep brain stimulation, in particular for obsessive-compulsive disorder, replacing the former lesional stereotactic procedures.

The history of Sainte-Anne Hospital’s Neurosurgery Department sheds light on the initiation—yet fast reconsideration—of psychosurgery in France. This relatively more prudent attitude toward the practice of psychosurgery compared with other countries was probably due to the historically strong collaboration between psychiatrists and neurosurgeons in France.

Geoffrey Knight and his contribution to psychosurgery

This paper retraces the fundamental achievements of Geoffrey Knight (1906-1994), a British neurosurgeon and a pioneer in the field of psychosurgery. His career developed in the 1950s and 1960s, when-following the unregulated practice of frontal lobotomies-strong criticism arose in the medical community and in the general public against psychosurgery. Geoffrey Knight's clinical research focused on identifying new, selective targets to limit the side effects of psychosurgery while improving the outcome of patients affected by mental disorders. Following the example of William Beecher Scoville, he initially developed restricted orbital undercutting as a less invasive alternative to standard frontal lobotomy. He then developed stereotactic subcaudate tractotomy, with the use of an original stereotactic device. Knight stressed the importance of the anatomy and neurophysiology of the structures targeted in subcaudate tractotomy, with particular regard to the fibers connecting the anterior cingulate region, the amygdala, the orbitofrontal cortex, and the hypothalamus. Of interest, the role of these white matter connections has been recently recognized in deep brain stimulation for major depression and anorexia nervosa. This is perhaps the most enduring legacy of Knight to the field of psychosurgery. He refined frontal leucotomies by selecting a restricted target at the center of a network that plays a crucial role in controlling mood disorders. He then developed a safe, minimally invasive stereotactic operation to reach this target. His work, well ahead of his time, still represents a valid reference on which to build future clinical experience in the modern era of neuromodulation for psychiatric diseases.

Neolithic trepanation decoded- A unifying hypothesis: Has the mystery as to why primitive surgeons performed cranial surgery been solved?

The perplexing mystery of why so many trephined skulls from the Neolithic period have been uncovered all over the world representing attempts at primitive cranial surgery is discussed. More than 1500 trephined skulls have been uncovered throughout the world, from Europe and Scandinavia to North America, from Russia and China to South America (particularly in Peru). Most reported series show that from 5-10% of all skulls found from the Neolithic period have been trephined with single or multiple skull openings of various sizes. The unifying hypothesis proposed by the late medical historian Dr. Plinio Prioreschi (1930-2014) regarding the reason for these trepanations (trephinations) is analyzed. It is concluded that Dr. Prioreschi's cohesive explanation to explain the phenomenon is valid and that his intriguing hypothesis is almost certainly correct. In the opinion of this author, the mystery within an enigma has been solved.

Anatomic Study of the Central Core of the Cerebrum Correlating 7-T Magnetic Resonance Imaging and Fiber Dissection With the Aid of a Neuronavigation System

BACKGROUND:

Different strategies have been used to study the fiber tract anatomy of the human brain in vivo and ex vivo. Nevertheless, the ideal method to study white matter anatomy has yet to be determined because it should integrate information obtained from multiple sources.

OBJECTIVE:

We developed an anatomic method in cadaveric specimens to study the central core of the cerebrum combining traditional white matter dissection with high-resolution 7-T magnetic resonance imaging (MRI) of the same specimen coregistered using a neuronavigation system.

METHODS:

Ten cerebral hemispheres were prepared using the traditional Klingler technique. Before dissection, a structural ultrahigh magnetic field 7-T MRI study was performed on each hemisphere specifically prepared with surface fiducials for neuronavigation. The dissection was then performed from the medial hemispheric surface using the classic white fiber dissection technique. During each step of the dissection, the correlation between the anatomic findings and the 7-T MRI was evaluated with the neuronavigation system.

RESULTS:

The anatomic study was divided in 2 stages: diencephalic and limbic. The diencephalic stage included epithalamic, thalamic, hypothalamic, and subthalamic components. The limbic stage consisted of extending the dissection to complete the Papez circuit. The detailed information given by the combination of both methods allowed us to identify and validate the position of fibers that may be difficult to appreciate and dissect (ie, the medial forebrain bundle).

CONCLUSION:

The correlation of high-definition 7-T MRI and the white matter dissection technique with neuronavigation significantly improves the understanding of the structural connections in complex areas of the human cerebrum.

Violence, mental illness, and the brain - A brief history of psychosurgery: Part 3 - From deep brain stimulation to amygdalotomy for violent behavior, seizures, and pathological aggression in humans

In the final installment to this three-part, essay-editorial on psychosurgery, we relate the history of deep brain stimulation (DBS) in humans and glimpse the phenomenal body of work conducted by Dr. Jose Delgado at Yale University from the 1950s to the 1970s. The inception of the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (1974-1978) is briefly discussed as it pertains to the "determination of the Secretary of Health, Education and Welfare regarding the recommendations and guidelines on psychosurgery." The controversial work - namely recording of brain activity, DBS, and amygdalotomy for intractable psychomotor seizures in patients with uncontrolled violence - conducted by Drs. Vernon H. Mark and Frank Ervin is recounted. This final chapter recapitulates advances in neuroscience and neuroradiology in the evaluation of violent individuals and ends with a brief discussion of the problem of uncontrolled rage and "pathologic aggression" in today's modern society - as violence persists, and in response, we move toward authoritarianism, with less freedom and even less dignity.

Violence, mental illness, and the brain - A brief history of psychosurgery: Part 1 - From trephination to lobotomy

Psychosurgery was developed early in human prehistory (trephination) as a need perhaps to alter aberrant behavior and treat mental illness. The “American Crowbar Case” provided an impetus to study the brain and human behavior. The frontal lobe syndrome was avidly studied. Frontal lobotomy was developed in the 1930s for the treatment of mental illness and to solve the pressing problem of overcrowding in mental institutions in an era when no other forms of effective treatment were available. Lobotomy popularized by Dr. Walter Freeman reached a zenith in the 1940s, only to come into disrepute in the late 1950s. Other forms of therapy were needed and psychosurgery evolved into stereotactic functional neurosurgery. A history of these developments up to the 21st century will be related in this three-part essay-editorial, exclusively researched and written for the readers of Surgical Neurology International (SNI).

What would surgeons like from materials scientists?

Surgery involves the repair, resection, replacement, or improvement of body parts and functions and in numerous ways, surgery should be considered human engineering. There are many areas in which surgical materials could be improved, but surgeons are generally unaware of materials available for use, while materials scientists do not know what surgeons require. This article will review some of the areas where surgeons and materials scientists have interacted in the past and will discuss some of the most pressing problems which remain to be solved. These include better implant materials for hernia repair, breast reconstruction, the treatment of diabetes, vascular stenting and reconstruction, and electrical pacing devices. The combination of tissue engineering and nanomaterials has great potential for application to nearly every aspect of surgery. Tissue engineering will allow cells or artificial organs to be grown for specific uses while nanotechnology will help to ensure maximal biocompatibility. Biosensors will be combined with improved electrodes and pacing devices to control impaired neurological functions.

A primer on brain-machine interfaces, concepts, and technology: a key element in the future of functional neurorestoration

Conventionally, the practice of neurosurgery has been characterized by the removal of pathology, congenital or acquired. The emerging complement to the removal of pathology is surgery for the specific purpose of restoration of function. Advents in neuroscience, technology, and the understanding of neural circuitry are creating opportunities to intervene in disease processes in a reparative manner, thereby advancing toward the long-sought-after concept of neurorestoration. Approaching the issue of neurorestoration from a biomedical engineering perspective is the rapidly growing arena of implantable devices. Implantable devices are becoming more common in medicine and are making significant advancements to improve a patient's functional outcome. Devices such as deep brain stimulators, vagus nerve stimulators, and spinal cord stimulators are now becoming more commonplace in neurosurgery as we utilize our understanding of the nervous system to interpret neural activity and restore function. One of the most exciting prospects in neurosurgery is the technologically driven field of brain-machine interface, also known as brain-computer interface, or neuroprosthetics. The successful development of this technology will have far-reaching implications for patients suffering from a great number of diseases, including but not limited to spinal cord injury, paralysis, stroke, or loss of limb. This article provides an overview of the issues related to neurorestoration using implantable devices with a specific focus on brain-machine interface technology.

A Bosphorus submarine passage and the reinvention of neurosurgery

One of the major themes characterizing the emergence of modern neurosurgery has been the concept of technology transfer and the application of a broad spectrum of revolutionary elements of technology from both physical and biological science. These transference applications are now apparent in modern neurosurgery as it is practiced on all continents of the globe. More than 3 decades ago, these ideas that now have come to fruition were in states of formulation. This article describes and further documents one such fertile cauldron of ideas and practical realities--the United States Navy Nuclear Submarine Service and its role and affect on the life and professional career of an academic neurosurgeon who was active in areas of progress as modernity was established for the early 21st century.