Mechanics Strategies for Implantation of Flexible Neural Probes

Abstract Flexible polymer-based neural probes are promising tools to interfaces with brain tissue since the low stiffness and thin geometry of these probes make them compliant to soft tissue in a manner that allows for reducing the inflammation responses. However, the same properties make flexible probes susceptible to bending and buckling during insertion, which make the implantation impossible. This paper provides a brief review of recent advances in mechanics strategies to assist the insertion of flexible probes. The basic concept of each strategy is summarized with advantages and disadvantages briefly discussed. These results provide a guide for reliable implantations of flexible neural probes for chronic brain electrophysiological recording and clinical treatment of neurological disorders.

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Hybrid Multisite Silicon Neural Probe with Integrated Flexible Connector for Interchangeable Packaging

Sensors ◽

10.3390/s21082605 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2605

Author(s):

Ashley Novais ◽

Carlos Calaza ◽

José Fernandes ◽

Helder Fonseca ◽

Patricia Monteiro ◽

...

Keyword(s):

Fabrication Process ◽

High Signal ◽

Wafer Level ◽

Neural Probes ◽

Insertion Force ◽

Precise Integration ◽

Flexible Cable ◽

Flexible Polymer ◽

Hybrid Silicon

Multisite neural probes are a fundamental tool to study brain function. Hybrid silicon/polymer neural probes combine rigid silicon and flexible polymer parts into one single device and allow, for example, the precise integration of complex probe geometries, such as multishank designs, with flexible biocompatible cabling. Despite these advantages and benefiting from highly reproducible fabrication methods on both silicon and polymer substrates, they have not been widely available. This paper presents the development, fabrication, characterization, and in vivo electrophysiological assessment of a hybrid multisite multishank silicon probe with a monolithically integrated polyimide flexible interconnect cable. The fabrication process was optimized at wafer level, and several neural probes with 64 gold electrode sites equally distributed along 8 shanks with an integrated 8 µm thick highly flexible polyimide interconnect cable were produced. The monolithic integration of the polyimide cable in the same fabrication process removed the necessity of the postfabrication bonding of the cable to the probe. This is the highest electrode site density and thinnest flexible cable ever reported for a hybrid silicon/polymer probe. Additionally, to avoid the time-consuming bonding of the probe to definitive packaging, the flexible cable was designed to terminate in a connector pad that can mate with commercial zero-insertion force (ZIF) connectors for electronics interfacing. This allows great experimental flexibility because interchangeable packaging can be used according to experimental demands. High-density distributed in vivo electrophysiological recordings were obtained from the hybrid neural probes with low intrinsic noise and high signal-to-noise ratio (SNR).

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Heart and Brain Tissue Banks for Research on Co-Occurring Cardiovascular and Neurological/Psychiatric Disorders

Cardiovascular Psychiatry and Neurology ◽

10.1155/2009/427840 ◽

2009 ◽

Vol 2009 ◽

pp. 1-3 ◽

Cited By ~ 1

Author(s):

Milos D. Ikonomovic

Keyword(s):

Brain Tissue ◽

Neurological Disorders ◽

Epidemiological Studies ◽

Biological Research ◽

Tissue Banks ◽

Practical Reasons ◽

Tissue Storage ◽

Tissue Samples ◽

Organ Systems ◽

Clinical Records

Epidemiological studies point to a strong and possibly causal association of psychiatric and neurological disorders with cardiovascular disease (CVD). Mechanistic links between these co-occurring illnesses are not well understood. Better insight into their relationship could help identify novel diagnostic markers and therapeutic targets. For successful translation of basic biomedical research into clinical practice, analyses of postmortem human tissues are essential. However, current tissue banks dedicated to psychiatric and neurological research collect only brain tissue samples deemed most important to the institution's participating investigators. While this practice is often dictated by budget constraints, restricted tissue storage space and other practical reasons, it limits the ability of the biological research community to access and study multiple organ systems relevant to cardiovascular and neuronal systems dysfunction. This problem is worsened when clinical records pertaining to coexistent systemic pathology are not available. To promote further understanding of co-occurring CVD and psychiatric/neurological disorders, efforts should be made to support tissue banks that harvest heart, coronary arteries, and aorta samples as well as brain tissue, from the same subjects.

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Abdominal Implantation of Testicles in the Management of Intractable Testicular Pain in Fournier Gangrene

International Surgery ◽

10.9738/intsurg-d-13-00113.1 ◽

2013 ◽

Vol 98 (4) ◽

pp. 367-371 ◽

Cited By ~ 4

Author(s):

Cyrus C. Chan ◽

Khaled Shahrour ◽

Ronald D. Collier ◽

Marlene Welch ◽

Shiliang Chang ◽

...

Keyword(s):

Soft Tissue ◽

Severe Pain ◽

Skin Grafts ◽

Suitable Alternative ◽

Necrotizing Soft Tissue Infection ◽

Advantages And Disadvantages ◽

Testicular Pain ◽

Fournier Gangrene ◽

Thickness Skin ◽

Definitive Management

Abstract Fournier gangrene (FG) is a necrotizing soft tissue infection involving the superficial and fascial planes of the perineum. In many cases of FG, debridement of the scrotum is necessary, leaving definitive management of the exposed testicles a significant surgical challenge. Frequent incidental trauma to the testicles can cause severe pain, especially in laborers. Practical surgical solutions are few and not well detailed. Various options exist, including creating a neoscrotum with adjacent thigh tissue, split-thickness skin grafts (STSGs), or even creating a subcutaneous thigh pocket. We describe a case of abdominal implantation of bilateral testicles for persistent testicular pain in a case where STSGs did not provide adequate protection, adjacent thigh skin was not available for creation of a neoscrotum, and significant cord contracture occurred. We detail the advantages and disadvantages of the commonly described techniques, including this approach, and how in select individuals this may be a suitable alternative.

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Demonstration of cortical recording and reduced inflammatory response using flexible polymer neural probes

10.1109/memsys.2007.4433162 ◽

2007 ◽

Cited By ~ 5

Author(s):

Andre Mercanzini ◽

Karen Cheung ◽

Derek Buhl ◽

Marc Boers ◽

Anne Maillard ◽

...

Keyword(s):

Inflammatory Response ◽

Neural Probes ◽

Flexible Polymer

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Optical phased array neural probes for beam-steering in brain tissue

Optics Letters ◽

10.1364/ol.441609 ◽

2021 ◽

Author(s):

Wesley Sacher ◽

Fu-Der Chen ◽

Homeira Moradi-Chameh ◽

Xinyu Liu ◽

Ilan Felts Almog ◽

...

Keyword(s):

Brain Tissue ◽

Phased Array ◽

Beam Steering ◽

Neural Probes ◽

Optical Phased Array

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Застосування екстракортикального остеосинтезу за діафізарних переломів кісток кінцівок у собак

Scientific Messenger of LNU of Veterinary Medicine and Biotechnology ◽

10.15421/nvlvet7704 ◽

2017 ◽

Vol 19 (77) ◽

pp. 15-17

Author(s):

V.S. Dmytriev ◽

N.M. Khomyn

Keyword(s):

Soft Tissue ◽

Tissue Injury ◽

Soft Tissue Injury ◽

Axial Deformation ◽

Advantages And Disadvantages ◽

Injured Area ◽

Different Types ◽

Diaphyseal Fractures ◽

Orthopedic Diseases ◽

Methods Of Treatment

The article presents an analysis of research results of domestic and foreign veterinary scientists concerning different treatments for dogs fractures of extremities. The researchers recommend to apply both conservative and radical treatment of orthopedic diseases, consisting in the use of different types of stable functional osteosynthesis (intramedullary, extra cortical and perosseous), creating conditions for early functioning of the injured area and the process of bone regeneration in the area of the fracture. It was established advantages and disadvantages of extra cortical osteogenesis and the feasibility of its application for diaphyseal fractures of extremities fractures in dogs. So, preference of closed intramedullary osteosynthesis consist in insignificant soft tissue injury. The downside is that that operation is performed blindly; is possible the injury of main nerves by pin, blood vessels, bones cracking. It is widely used open intramedullary drawback – destruction of bone marrow, vessels, circulatory disorders around the metal; reoperation is required to remove the metal holder. Extra cortical method provides reliable fixation of debris, especially for complex comminuted fracture. The disadvantage is the trauma during the imposition and removal of plates, infection of wounds. Perosseous allows to treat fractures of various localization, limb elongation, eliminate axial deformation and defects in bone and soft tissue of any origin and location, particularly complicated by osteomyelitis. But for its application requires special expensive equipment. Therefore becomes important the improvement of radical methods of treatment of fractures in order to stimulate regenerative processes and elimination of complications in the postoperative period.

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Modulated focused ultrasound for treatment of de-myelinating axons in multiple sclerosis lesions – pilot animal studies

10.31225/osf.io/vqbef ◽

2018 ◽

Author(s):

Pierre D. Mourad

Keyword(s):

Multiple Sclerosis ◽

Mouse Model ◽

Brain Tissue ◽

Neurological Disorders ◽

Animal Studies ◽

Focused Ultrasound ◽

Neural Circuits ◽

Laser Light ◽

Non Invasive ◽

Pulsed Focused Ultrasound

Multiple sclerosis is a debilitating disease whose symptoms arise from de-myelination of axons within brain tissue with an attendant loss of central and peripheral function. We among others have shown that transcranial delivery of pulsed focused ultrasound (pFU) can non-destructively activate central neural circuits. Others have shown enhanced myelin remodeling of axons activated by laser light in an optogenetic mouse model. We hypothesize that pFU activation of axons within MS lesions in a rodent model will decrease their de-myelination and increase their re-myelination. If successful, this non-invasive therapy may lead to rapid advancements in the treatment of MS and other de-myelinating neurological disorders.

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A review: A Comprehensive Review of Soft and Rigid Wearable Rehabilitation and Assistive Devices with a Focus on the Shoulder Joint

Journal of Intelligent & Robotic Systems ◽

10.1007/s10846-021-01353-x ◽

2021 ◽

Vol 102 (1) ◽

Author(s):

Hamed Majidi Fard Vatan ◽

Samia Nefti-Meziani ◽

Steve Davis ◽

Zahra Saffari ◽

Haitham El-Hussieny

Keyword(s):

Neurological Disorders ◽

Shoulder Joint ◽

Clinical Evidence ◽

Assistive Devices ◽

Daily Activities ◽

Advantages And Disadvantages ◽

Robotic Devices ◽

User Friendly ◽

Human Upper Limb ◽

Comprehensive Study

AbstractThe importance of the human upper limb role in performing daily life and personal activities is significant. Improper functioning of this organ due to neurological disorders or surgeries can greatly affect the daily activities performed by patients. This paper aims to comprehensively review soft and rigid wearable robotic devices provided for rehabilitation and assistance focusing on the shoulder joint. In the last two decades, many devices have been proposed in this regard, however, there have been a few groups whose devices have had effective therapeutic capability with acceptable clinical evidence. Also, there were not many portable, lightweight and user-friendly devices. Therefore, this comprehensive study could pave the way for achieving optimal future devices, given the growing need for these devices. According to the results, the most commonly used plan was Exoskeleton, the most commonly used actuators were electrical, and most devices were considered to be stationary and rigid. By doing these studies, the advantages and disadvantages of each method are also presented. The presented devices each have a new idea and attitude in a specific field to solve the problems of movement disorders and rehabilitation, which were in the form of prototypes, initial clinical studies and sometimes comprehensive clinical and commercial studies. These plans need more comprehensive clinical trials to become a complete and efficient plan. This article could be used by researchers to identify and evaluate the important features and strengths and weaknesses of the plans to lead to the presentation of more optimal plans in the future.

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