Transorbital Alternating Current Stimulation in a Double-Masked Randomized Clinical Trial: Visual Functional Effect and Quality of Life.

Purpose: To determine the efficacy and safety of repetitive transorbital alternating current stimulation (rtACS) treatment by assessing vision-related quality of life and visual function outcome in subjects treated with rtACS versus sham-control.

Study Design: Double masked, randomized, sham-controlled clinical trial (NCT03188042).

Subjects: Sixteen subjects with moderate-to-advanced glaucoma (visual field [VF] mean deviation [MD] ≤-6.

Adaptive and Maladaptive Brain Functional Network Reorganization After Stroke in Hemianopia Patients: An Electroencephalogram-Tracking Study.

Hemianopia after occipital stroke is believed to be mainly due to local damage at or near the lesion site. However, magnetic resonance imaging studies suggest functional connectivity network (FCN) reorganization also in distant brain regions. Because it is unclear whether reorganization is adaptive or maladaptive, compensating for, or aggravating vision loss, we characterized FCNs electrophysiologically to explore and brain plasticity and correlated FCN reorganization with visual performance.

Reorganization of Brain Functional Connectivity Network and Vision Restoration Following Combined tACS-tDCS Treatment After Occipital Stroke.

Non-invasive brain stimulation (NIBS) is already known to improve visual field functions in patients with optic nerve damage and partially restores the organization of brain functional connectivity networks (FCNs). However, because little is known if NIBS is effective also following brain damage, we now studied the correlation between visual field recovery and FCN reorganization in patients with stroke of the central visual pathway. In a controlled, exploratory trial, 24 patients with hemianopia were randomly assigned to one of three brain stimulation groups: transcranial direct current stimulation (tDCS)/transcranial alternating current stimulation (tACS) (ACDC); sham tDCS/tACS (AC); sham tDCS/sham tACS (Sham), which were compared to age-matched controls ( = 24).

Non-invasive electrical brain stimulation for vision restoration after stroke: An exploratory randomized trial (REVIS).

Background: Occipital strokes often cause permanent homonymous hemianopia leading to significant disability. In previous studies, non-invasive electrical brain stimulation (NIBS) has improved vision after optic nerve damage and in combination with training after stroke.

Objective: We explored different NIBS modalities for rehabilitation of hemianopia after chronic stroke.

Mesoscopic cortical network reorganization during recovery of optic nerve injury in GCaMP6s mice.

As the residual vision following a traumatic optic nerve injury can spontaneously recover over time, we explored the spontaneous plasticity of cortical networks during the early post-optic nerve crush (ONC) phase. Using in vivo wide-field calcium imaging on awake Thy1-GCaMP6s mice, we characterized resting state and evoked cortical activity before, during, and 31 days after ONC. The recovery of monocular visual acuity and depth perception was evaluated in parallel.

Transcranial electrical stimulation nomenclature.

Transcranial electrical stimulation (tES) aims to alter brain function non-invasively by applying current to electrodes on the scalp. Decades of research and technological advancement are associated with a growing diversity of tES methods and the associated nomenclature for describing these methods. Whether intended to produce a specific response so the brain can be studied or lead to a more enduring change in behavior (e.

Pressure balance and imbalance in the optic nerve chamber: The Beijing Intracranial and Intraocular Pressure (iCOP) Study.

To determine the interdependence of intracranial pressure (ICP) and intraocular pressure (IOP) and how it affects optic nerve pressures, eight normal dogs were examined using pressure-sensing probes implanted into the left ventricle, lumbar cistern, optic nerve subarachnoid space in the left eye, and anterior chamber in the left eye. This allowed ICP, lumbar cistern pressure (LCP), optic nerve subarachnoid space pressure (ONSP) and IOP to be simultaneously recorded. After establishing baseline pressure levels, pressure changes that resulted from lowering ICP (via shunting cerebrospinal fluid (CSF) from the ventricle) were recorded.

Intracranial pressure (ICP) and optic nerve subarachnoid space pressure (ONSP) correlation in the optic nerve chamber: the Beijing Intracranial and Intraocular Pressure (iCOP) study.

Purpose: Because a lowered intracranial pressure (ICP) is a possible mechanism of optic neuropathy, we wished to study the CSF dynamics in the optic nerve chamber by recording possible changes in the optic nerve subarachnoid space pressure (ONSP) and the impact on it when acutely lowering ICP.

Methods: In eight normal dogs pressure probes were implanted in the left brain ventricle, lumbar cistern, optic nerve subarachnoid space and in the anterior eye chamber. Following CSF shunting from the brain ventricle we monitored changes of ICP, lumbar cistern pressure (LCP), ONSP and intraocular pressure (IOP).

Caspase-3 inhibitor Z-DEVD-FMK enhances retinal ganglion cell survival and vision restoration after rabbit traumatic optic nerve injury.

Purpose: Vision loss after traumatic optic nerve injury is considered irreversible because of the retrograde loss of retinal ganglion cells (RGCs) which undergo apoptosis. Because the second messenger caspase-3 plays a major role in apoptosis, we now evaluated the efficacy of the specific caspase-3 inhibitor, Z-DEVD-FMK, in a rabbit model of fluid percussion injury (FPI) which mimics traumatic optic nerve injury in humans to enhance cell survival and improve vision.

Methods: Survival of RGCs and recovery of vision were studied using retinal morphological markers and visual evoked potentials (VEP), respectively.

Publishing in the field of brain plasticity, repair and rehabilitation: an emerging neuroscience niche journal.

The journal Restorative Neurology and Neuroscience (RNN) is now published in its 25th volume since its inception in 1989. RNN focuses on the emerging field of brain plasticity, repair and rehabilitation, including original and review papers both in basic research (animal experiments, in vitro studies) and in the clinical domain, including brain imaging studies. During the last decade RNN has experienced a steady progress in its reference value and scientific impact.

Functional motor compensation in amyotrophic lateral sclerosis.

The present study investigated the fMRI correlates of functional compensation/neural reorganization of the motor system in patients with amyotrophic lateral sclerosis (ALS). The hypothesis was that ALS patients would recruit additional brain regions compared with controls in a motor task and that activity in these regions would vary as a function of task difficulty. Patients and controls executed a motor task with two sequences (a simple and a more difficult one) of consecutive button presses.

Neurotrauma and Plasticity A conference of the German BMBF-research initiative.

A conference was held in Magdeburg, Germany on March 4-6 where experts discussed current research in neurotraumatology and neurop-sychological rehabilitation. A total of about 60 research projects of a nationwide program project funded by the German Ministry of Education and Research (BMBF) were presented in conjunction with projects from the BMBF-initiative program "Neuropathology" of the Otto-v.-Guericke University of Magdeburg and the Graduate Program in Neuroscience which were funded by the German Research Society (DFG) and the State of Sachsen-Anhalt.

Restoration of vision IV: role of compensatory soma swelling of surviving retinal ganglion cells in recovery of vision after optic nerve crush.

Purpose: Diffuse axonal injury following partial optic nerve crush (ONC) leads to severe visual deficits from which rats can partially recover within 2-3 weeks. To evaluate tbc role of surviving retinal ganglion cells (RGCS) in recovery, we have observed their morphology repeatedly in vivo with ICON-microscopy and correlated cell size changes with recovery of vision which we observed in parallel in the same animals.

Methods: After rats had learned a visual contrast discrimination task using an automated, computer-based test, RGCs were labeled retrogradely with fluorescent beads.

Restoration of vision by training of residual functions.

A new paradigm emerges: visual field defects after optic nerve or brain injury are partially reversible. Using high-resolution visual field tests, areas of residual vision can be identified which are characterized by impaired vision (relative defect) with some residual capacities. By repetitively stimulating these partially damaged areas with daily computer-based visual restitution training it is now possible to enlarge the visual field.

Neurotrauma and plasticity a conference of the German BMBF-research initiative.

A conference was held in Magdeburg, Germany on March 4–6 where experts discussed current research in neurotraumatology and neurop-sychological rehabilitation. A total of about 60 research projects of a nationwide program project funded by the German Ministry of Education and Research (BMBF) were presented in conjunction with projects from the BMBF-initiative program “Neuropathology” of the Otto-v.-Guericke University of Magdeburg and the Graduate Program in Neuroscience which were funded by the German Research Society (DFG) and the State of Sachsen-Anhalt.

Computer-based training for the treatment of partial blindness.

Partial blindness after brain injury has been considered non-treatable. To evaluate whether patients with visual-field defects can profit from computer-based visual restitution training (VRT), two independent clinical trials were conducted using patients with optic nerve (n = 19) or post-chiasmatic brain injury (n = 19). In post-chiasma patients, VRT led to a significant improvement (29.

Isolation of functionally intact pig retina mitochondria.

Two alternative methods for the isolation of functionally intact mitochondria from pig retina were evaluated by means of differential centrifugation. If ATP and bovine serum albumin were present during the isolation procedures mitochondria exhibited ADP sensitive respiration and membrane potentials, comparable to values from other tissues. The mitochondria fraction of both methods differed in purity, being almost free of synaptosomes when a discontinuous Ficoll gradient centrifugation was used.

Neurotoxic reactions of CNS cells following gene transfer with defective herpes simplex virus (HSV-1) vector.

Defective herpes simplex virus (HSV-1) vector containing either the lac-z gene or the tyrosine-hydroxylase (TH) gene was added to primary rat neocortex cultures and gene transfer was assessed using immunohistochemical procedures. While we were able to confirm lac- and TH-expression in vitro, exposure to the vector was accompanied by marked neurotoxic reactions as indicated by severe cell loss in vitro. Furthermore, when genetically altered cells were implanted into the adult rat striatum, a few lac-z positive cells without neurites were present but not a single TH-expressing cell could be found.