This work has been partially supported by the National governments and the European Union through the ENIAC JU project DeNeCoR under grant agreement number 324257. The authors would like to thank Prof. Giovanni Magenes, Prof. Piero Tortoli and Dr. Giosu&#232; Caliano for their precious support, supervision, and insightful comments that made this work possible. We are also grateful to Prof. Egidio D'Angelo and his group (BCC Lab.), together with Fondazione Istituto Neurologico C. Mondino, for providing the motion tracking and MR instrumentation, and to Giancarlo Germani for MR acquisitions. Finally, we'd like to thank Dr. Nicoletta Caramia, Dr. Alessandro Dallai and Ms. Barbara Mauti for their valuable technical support and Mr. Walter Volpi for providing the bovine brain.

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The authors declare they have no competing financial interests.

Several works have been presented in the literature describing techniques that are similar or related to the protocol presented. These techniques are also based on the use of realistic targets, including fixed animal or cadaver brains, but they are mainly conceived for testing of digital registration methods of various sorts.
The protocol described here, however, has the specific purpose of testing US probes in different configurations in the early stages of development and, due to this, it fu...

<table><tbody><tr><td>ULA-OP</td><td>University of Florence</td><td>N/A</td><td>Ultrasound imaging research system</td></tr><tr><td>3D imaging piezeoelectric probe</td><td>Esaote s.p.a.</td><td>9600195000</td><td>Mechanically-swept 3D ultrasound probe, model BL-433</td></tr><tr><td>Linear-array piezoelectric probe</td><td>Esaote s.p.a.</td><td>122001100</td><td>Ultrasound linear array probe, model LA-533</td></tr><tr><td>CMUT probe</td><td>University Roma Tre</td><td>N/A</td><td>Ultrasound linear array probe based on CMUT technology</td></tr><tr><td>MAGNETOM Skyra 3T MR scanner</td><td>Siemens Healthcare</td><td>N/A</td><td>MR scanner</td></tr><tr><td>Head coil</td><td>Siemens Healthcare</td><td>N/A</td><td>32-channel head coil for MR imaging</td></tr><tr><td>NDI Polaris Vicra</td><td>NDI Medical</td><td>8700335001</td><td>Optical motion tracking system</td></tr><tr><td>Pointer tool</td><td>NDI Medical</td><td>8700340</td><td>Passive pointer tool with 4 reflecting markers</td></tr><tr><td>Clamp-equipped tool</td><td>NDI Medical</td><td>8700399</td><td>Rigid body with 4 reflecting markers and a clamp to be connected to the US probe handle</td></tr><tr><td>Bovine brain</td><td>N/A</td><td>N/A</td><td>Brain of an adult bovine, from food suppliers</td></tr><tr><td>Formalin solution</td><td>N/A</td><td>N/A</td><td>10% buffered formalin solution for bovine brain fixation - CAUTION, formalin is a toxic chemical substance and must be handled with care; specific regulations may also apply (see for instance US OSHA Standard 1910.1048 App A)</td></tr><tr><td>Plastic container for anatomical parts</td><td>N/A</td><td>N/A</td><td>Cilindrical plastic container with lid</td></tr><tr><td>Glass spheres</td><td>N/A</td><td>N/A</td><td>3 mm diameter spheres of Flint glass</td></tr><tr><td>Agar</td><td>N/A</td><td>N/A</td><td>30 g, for phantom preparation</td></tr><tr><td>Glycerine</td><td>AEFFE Farmaceutici</td><td>A908005248</td><td>100 g, for phantom preparation</td></tr><tr><td>Distilled water</td><td>Solbat Gaysol</td><td>8027391000015</td><td>870 g, for phantom preparation</td></tr><tr><td>Beaker</td><td>N/A</td><td>N/A</td><td>Beaker used for the diluition of glycerine and agar in distilled water</td></tr><tr><td>Lysoform</td><td>Lever</td><td>8000680500014</td><td>A benzalkonium chloride and water solution was used for the agar phantom preservation</td></tr><tr><td>Polystyrene mannequin head</td><td>N/A</td><td>N/A</td><td>Polyestirene model which was cutted and used to design the configuration of spheres&#039;patterns</td></tr><tr><td>Green tissue marking dye for histology</td><td>N/A</td><td>N/A</td><td>Colour used to mark the glass spheres&#039; positions on the bovine brain surface</td></tr><tr><td>Yellow enamel</td><td>N/A</td><td>N/A</td><td>Enamel used to colour the glass spheres implanted in the agar phantom</td></tr><tr><td>Water tank</td><td>N/A</td><td>N/A</td><td>50x50x30 cm plastic tank filled with degassed water up to a 15 cm height&amp;nbsp;</td></tr><tr><td>Mechanical arm</td><td>Esaote s.p.a.</td><td>N/A</td><td>Mechanical arm clamped to the water tank border and used to held the probe in fixed positions</td></tr><tr><td>Plate of synthetic resin</td><td>N/A</td><td>N/A</td><td>Plate used as a support for the bovine brain positioning in the water tank</td></tr><tr><td>Sewing threads</td><td>N/A</td><td>N/A</td><td>Sewing thread segments used to immobilize the brain on the resin plate</td></tr><tr><td>Adhesive tape</td><td>N/A</td><td>N/A</td><td>Adhesive tape used to fix the sewing thread extremities onto the resin plate</td></tr><tr><td>Plastic food container</td><td>N/A</td><td>N/A</td><td>Sealed food container used for the agar phantom</td></tr><tr><td>Notebook</td><td>Lenovo</td><td>Z50-70</td><td>Lenovo&amp;nbsp; Z50-70, Intel(R) Core i7-4510U @ 2.0 GHz, 8 GB RAM</td></tr><tr><td>Workstation</td><td>Dell Inc.</td><td>T5810</td><td>Intel(R) Xeon(R) CPU E3-1240v3 @ 3.40 GHz, 16 GB RAM</td></tr><tr><td>Matlab</td><td>The MathWorks</td><td>R2013a</td><td>Software tool, used for space transformation computation and 3D reconstruction from image planes</td></tr><tr><td>Paraview</td><td>Kitware Inc.</td><td>v. 4.4.1</td><td>Open-source software for 3D image processing and visualization</td></tr><tr><td>NDI Toolbox - ToolTracker Utility</td><td>NDI Medical</td><td>v. 4.007.007</td><td>Software for marker position visualization and tracking in the NDI Polaris Vicra measurement volume</td></tr><tr><td>C++ data-logging software</td><td>NDI Medical</td><td>v. 4.007.007</td><td>Software for marker position recording on a text log file</td></tr><tr><td>ULA-OP software&amp;nbsp;</td><td>University of Florence</td><td>N/A</td><td>Software for real-time display and control of the ULA-OP system</td></tr></tbody></table>

an experimental protocol for assessing the performance of new ultrasound probes based on cmut technology in application to brain imaging

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ultrasound (US) probes. Particularly, a more realistic analysis with application-specific imaging targets can be extremely valuable to assess the expected performance of US probes in their potential clinical field of application.
The experimental protocol presented in this work was purposely designed to provide an application-specific assessment procedure for newly-developed US probe prototypes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology in relation to brain imaging.
The protocol combines the use of a bovine brain fixed in formalin as the imaging target, which ensures both realism and repeatability of the described procedures, and of neuronavigation techniques borrowed from neurosurgery. The US probe is in fact connected to a motion tracking system which acquires position data and enables the superposition of US images to reference Magnetic Resonance (MR) images of the brain. This provides a means for human experts to perform a visual qualitative assessment of the US probe imaging performance and to compare acquisitions made with different probes. Moreover, the protocol relies on the use of a complete and open research and development system for US image acquisition, i.e. the Ultrasound Advanced Open Platform (ULA-OP) scanner.
The manuscript describes in detail the instruments and procedures involved in the protocol, in particular for&#160;the calibration, image acquisition and registration of US and MR images. The obtained results prove the effectiveness of the overall protocol presented, which is entirely open (within the limits of the instrumentation involved), repeatable, and covers the entire set of acquisition and processing activities for US images.

The main result achieved via the described protocol is the experimental validation of an effective and repeatable assessment procedure for the 2D and 3D imaging capabilities of US probe prototypes based on CMUT technology, in the prospective application to brain imaging. After implementing all the described protocol steps, an expert can then apply the visualization software functions (e.g. free orientation slicing, subset extraction, volume interpolation, etc.) to compar...

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An Experimental Protocol for Assessing the Performance of New Ultrasound Probes Based on CMUT Technology in Application to Brain Imaging

The development of new ultrasound (US) probes based on Capacitive Micromachined Ultrasonic Transducer (CMUT) technology requires an early realistic assessment of imaging capabilities. We describe a repeatable experimental protocol for US image acquisition and comparison with magnetic resonance images, using an ex vivo bovine brain as an imaging target.

The possibility to perform an early and repeatable assessment of imaging performance is fundamental in the design and development process of new ...

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10.4K Views.  University of Pavia. De ontwikkeling van nieuwe echografie (VS)-sondes gebaseerd op capacitieve Micromachined ultrasone Transducer (CMUT) technologie vereist een vroege realistische inschatting van beeldvormende mogelijkheden. We beschrijven een herhaalbare experimenteel protocol voor Amerikaanse Beeldacquisitie en vergelijking met magnetische resonantie beelden, met behulp van een ex vivo boviene hersenen als een imaging doel.

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High-throughput, Automated Extraction of DNA and RNA from Clinical Samples using TruTip Technology on Common Liquid Handling Robots

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. The geometry of the monolith can be adapted for specific pipette tips ranging in volume from 1.0 to 5.0 ml. The large porosity of the monolith enables viscous or complex samples to readily pass through it with minimal fluidic backpressure. Bi-directional flow maximizes residence time between the monolith and sample, and enables large sample volumes to be processed within a single TruTip. The fundamental steps, irrespective of sample volume or TruTip geometry, include cell lysis, nucleic acid binding to the inner pores of the TruTip monolith, washing away unbound sample components and lysis buffers, and eluting purified and concentrated nucleic acids into an appropriate buffer. The attributes and adaptability of TruTip are demonstrated in three automated clinical sample processing protocols using an Eppendorf epMotion 5070, Hamilton STAR and STARplus liquid handling robots, including RNA isolation from nasopharyngeal aspirate, genomic DNA isolation from whole blood, and fetal DNA extraction and enrichment from large volumes of maternal plasma (respectively).

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. Consequently, the sample preparation format is compatible with most liquid handling instruments, and can be used for many medium to high-throughput clinical applications and sample types.

TruTip is a simple nucleic acid extraction  technology whereby a porous, monolithic binding matrix is inserted into a  pipette tip. The geometry of the ...

Non-invasive Parenchymal, Vascular and Metabolic High-frequency Ultrasound and Photoacoustic Rat Deep Brain Imaging

Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central nervous system of small animals. However, transdermal and transcranial neuroimaging is frequently affected by low sensitivity, image aberrations and loss of space resolution, requiring scalp or even skull removal before imaging. To overcome this challenge, a new protocol is presented to gain significant insights in brain hemodynamics by photoacoustic and high-frequency ultrasounds imaging with the animal skin and skull intact. The procedure relies on the passage of ultrasound (US) waves and laser directly through the fissures that are naturally present on the animal cranium. By juxtaposing the imaging transducer device exactly in correspondence to these selected areas where the skull has a reduced thickness or is totally absent, one can acquire high quality deep images and explore internal brain regions that are usually difficult to anatomically or functionally describe without an invasive approach. By applying this experimental procedure, significant data can be collected in both sonic and optoacoustic modalities, enabling to image the parenchymal and the vascular anatomy far below the head surface. Deep brain features such as parenchymal convolutions and fissures separating the lobes were clearly visible. Moreover, the configuration of large and small blood vessels was imaged at several millimeters of depth, and precise information were collected about blood fluxes, vascular stream velocities and the hemoglobin chemical state. This repertoire of data could be crucial in several research contests, ranging from brain vascular disease studies to experimental techniques involving the systemic administration of exogenous chemicals or other objects endowed with imaging contrast enhancement properties. In conclusion, thanks to the presented protocol, the US and PA techniques become an attractive noninvasive performance-competitive means for cortical and internal brain imaging, retaining a significant potential in many neurologic fields.

The present work describes a new protocol to perform non-invasive high-frequency ultrasound and photoacoustic based imaging on rat brain, to efficiently visualize deep subcortical regions and their vascular patterns by directing signals on skull foramina naturally present on animal cranium.

Photoacoustics and high frequency ultrasound stands out as powerful tools for neurobiological applications enabling high-resolution imaging on the central ...

Neuroscience

Real-Time Intravital Multiphoton Microscopy to Visualize Focused Ultrasound and Microbubble Treatments to Increase Blood-Brain Barrier Permeability

The blood-brain barrier (BBB) is a key challenge for the successful delivery of drugs to the brain. Ultrasound exposure in the presence of microbubbles has emerged as an effective method to transiently and locally increase the permeability of the BBB, facilitating para- and transcellular transport of drugs across the BBB. Imaging the vasculature during ultrasound-microbubble treatment will provide valuable and novel insights on the mechanisms and dynamics of ultrasound-microbubble treatments in the brain.
Here, we present an experimental procedure for intravital multiphoton microscopy using a cranial window aligned with a ring transducer and a 20x objective lens. This set-up enables high spatial and temporal resolution imaging of the brain during ultrasound-microbubble treatments. Optical access to the brain is obtained via an open-skull cranial window. Briefly, a 3-4 mm diameter piece of the skull is removed, and the exposed area of the brain is sealed with a glass coverslip. A 0.82 MHz ring transducer, which is attached to a second glass coverslip, is mounted on top. Agarose (1% w/v) is used between the coverslip of the transducer and the coverslip covering the cranial window to prevent air bubbles, which impede ultrasound propagation. When sterile surgery procedures and anti-inflammatory measures are taken, ultrasound-microbubble treatments and imaging sessions can be performed repeatedly over several weeks. Fluorescent dextran conjugates are injected intravenously to visualize the vasculature and quantify ultrasound-microbubble induced effects (e.g., leakage kinetics, vascular changes). This paper describes the cranial window placement, ring transducer placement, imaging procedure, common troubleshooting steps, as well as advantages and limitations of the method.

This protocol describes the surgical and technical procedures that enable real-time in vivo multiphoton fluorescence imaging of the rodent brain during focused ultrasound and microbubble treatments to increase blood-brain barrier permeability.

The blood-brain barrier (BBB) is a key challenge for the successful delivery of drugs to the brain. Ultrasound exposure in the presence of microbubbles ...

A Bedside, Single Burr Hole Approach to Multimodality Monitoring in Severe Brain Injury

Intracranial pressure (ICP) monitoring is a cornerstone of the intensive care management of patients with severe acute brain injuries, including traumatic brain injury. While elevations in ICP are common, data regarding the measurement and treatment of these ICP elevations are conflicting. There is increasing recognition that changes in the balance between supply and demand of brain tissue are critically important and therefore the measurement of multiple modalities is required. Approaches are not standard, and therefore this article provides a description of a bedside, single burr hole approach to multimodality monitoring that allows the passage of probes designed to measure not only ICP but brain tissue oxygen, blood flow, and intracranial electroencephalography. Patient selection criteria, operative procedures, and practical considerations for securing probes during critical care are described. This method is readily performed, safe, secure, and flexible for the adoption of a variety of multimodality monitoring approaches aimed at detecting or preventing secondary brain injuries.

A method of recording multimodality monitoring signals in patients with severe brain injuries using a bedside, single burr hole technique is described.

Intracranial pressure (ICP) monitoring is a cornerstone of the intensive care management of patients with severe acute brain injuries, including traumatic ...

Whole-Brain 3D Activation and Functional Connectivity Mapping in Mice using Transcranial Functional Ultrasound Imaging

Functional ultrasound (fUS) imaging is a novel brain imaging modality that relies on the high-sensitivity measure of the cerebral blood volume achieved by ultrafast doppler angiography. As brain perfusion is strongly linked to local neuronal activity, this technique allows the whole-brain 3D mapping of task-induced regional activation as well as resting-state functional connectivity, non-invasively, with unmatched spatio-temporal resolution and operational simplicity. In comparison with fMRI (functional magnetic resonance imaging), a main advantage of fUS imaging consists in enabling a complete compatibility with awake and behaving animal experiments. Moreover, fMRI brain mapping in mice, the most used preclinical model in Neuroscience, remains technically challenging due to the small size of the brain and the difficulty to maintain stable physiological conditions. Here we present a simple, reliable and robust protocol for whole-brain fUS imaging in anesthetized and awake mice using an off-the-shelf commercial fUS system with a motorized linear transducer, yielding significant cortical activation following sensory stimulation as well as reproducible 3D functional connectivity pattern for network identification.

This protocol describes the quantification of volumetric cerebral hemodynamic variations in the mouse brain using functional ultrasound (fUS). Procedures for 3D functional activation map following sensory stimulation as well as resting-state functional connectivity are provided as illustrative examples, in anesthetized and awake mice.

Functional ultrasound (fUS) imaging is a novel brain imaging modality that relies on the high-sensitivity measure of the cerebral blood volume achieved by ...

Non-Invasive Integrated PAUSAT Whole-Brain Imaging of Ischemic Stroke

Integrated Photoacoustic, Ultrasound, and Angiographic Tomography (PAUSAT) for NonInvasive Whole-Brain Imaging of Ischemic Stroke

Presented here is an experimental ischemic stroke study using our newly developed noninvasive imaging system that integrates three acoustic-based imaging technologies: photoacoustic, ultrasound, and angiographic tomography (PAUSAT). Combining these three modalities helps acquire multi-spectral photoacoustic tomography (PAT) of the brain blood oxygenation, high-frequency ultrasound imaging of the brain tissue, and acoustic angiography of the cerebral blood perfusion. The multi-modal imaging platform allows the study of cerebral perfusion and oxygenation changes in the whole mouse brain after stroke. Two commonly used ischemic stroke models were evaluated: the permanent middle cerebral artery occlusion (pMCAO) model and the photothrombotic (PT) model. PAUSAT was used to image the same mouse brains before and after a stroke and quantitatively analyze both stroke models. This imaging system was able to clearly show the brain vascular changes after ischemic stroke, including significantly reduced blood perfusion and oxygenation in the stroke infarct region (ipsilateral) compared to the uninjured tissue (contralateral). The results were confirmed by both laser speckle contrast imaging and triphenyltetrazolium chloride (TTC) staining. Furthermore, stroke infarct volume in both stroke models was measured and validated by TTC staining as the ground truth. Through this study, we have demonstrated that PAUSAT can be a powerful tool in noninvasive and longitudinal preclinical studies of ischemic stroke.

Author Spotlight: Integrated Photoacoustic, Ultrasound, and Angiographic Tomography (PAUSAT) for NonInvasive Whole-Brain Imaging of Ischemic Stroke  

This work demonstrates the use of a multimodal ultrasound-based imaging platform for noninvasive imaging of ischemic stroke. This system allows for the quantification of blood oxygenation through photoacoustic imaging and impaired perfusion in the brain through acoustic angiography.

Presented here is an experimental ischemic stroke study using our newly developed noninvasive imaging system that integrates three acoustic-based imaging ...

High-Precision TUS: Planning and Execution with Acoustic and Thermal Simulations

Pipeline for Planning and Execution of Transcranial Ultrasound Neuromodulation Experiments in Humans

Transcranial ultrasound stimulation (TUS) is an emerging non-invasive neuromodulation technique capable of manipulating both cortical and subcortical structures with high precision. Conducting experiments involving humans necessitates careful planning of acoustic and thermal simulations. This planning is essential to adjust for bone interference with the ultrasound beam's shape and trajectory and to ensure TUS parameters meet safety requirements. T1- and T2-weighted, along with zero-time echo (ZTE) magnetic resonance imaging (MRI) scans with 1 mm isotropic resolution, are acquired (alternatively computed tomography x-ray (CT) scans) for skull reconstruction and simulations. Target and trajectory mapping are performed using a neuronavigational platform. SimNIBS is used for the initial segmentation of the skull, skin, and brain tissues. Simulation of TUS is carried over with the BabelBrain tool, which uses the ZTE scan to produce synthetic CT images of the skull to be converted into acoustic properties. We use a phased array ultrasound transducer with electrical steering capabilities. Z-steering is adjusted to ensure that the target depth is reached. Other transducer configurations are also supported in the planning tool. Thermal simulations are run to ensure temperature and mechanical index requirements are within the acoustic guidelines for TUS in human subjects as recommended by the FDA. During TUS delivery sessions, a mechanical arm assists in the movement of the transducer to the required location using a frameless stereotactic localization system.

Author Spotlight: Advancing Human Brain Modulation &#8211; Optimized Protocols for Transcranial Ultrasound Stimulation Experiments

Transcranial ultrasound stimulation (TUS) is an emerging non-invasive neuromodulation technique that requires careful planning of acoustic and thermal simulations. The methodology describes an image processing and ultrasound simulation pipeline for efficient, user-friendly, streamlined planning for human TUS experimentation.

Transcranial ultrasound stimulation (TUS) is an emerging non-invasive neuromodulation technique capable of manipulating both cortical and subcortical ...

Enhancing Drug Delivery to the Brain: MRI-Guided Ultrasound Techniques in Rats

Monitoring Blood-Brain Barrier Opening in Rats with a Preclinical Focused Ultrasound System

The brain has a highly selective semipermeable blood barrier, termed the blood-brain barrier (BBB), which prevents the delivery of therapeutic macromolecular agents to the brain. The integration of MR-guided low-intensity pulsed focused ultrasound (FUS) with microbubble pre-injection is a promising technique for non-invasive and non-toxic BBB modulation. MRI can offer superior soft-tissue contrast and various quantitative assessments, such as vascular permeability, perfusion, and the spatial-temporal distribution of MRI contrast agents. Notably, contrast-enhanced MRI techniques with gadolinium-based MR contrast agents have been shown to be the gold standard for detecting BBB openings. This study outlines a comprehensive methodology involving MRI protocols and animal procedures for monitoring BBB opening in a rat model. The rat model provides the added benefit of jugular vein catheter utilization, which facilitates rapid medication administration. A stereotactic-guided preclinical FUS transducer facilitates the refinement and streamlining of animal procedures and MRI protocols. The resulting methods are characterized by reproducibility and simplicity, eliminating the need for specialized surgical expertise. This research endeavors to contribute to the optimization of preclinical procedures with rat models and encourage further investigation into the modulation of the BBB to enhance therapeutic interventions in neurological disorders.

This study describes a combined magnetic resonance imaging (MRI) and low-intensity pulsed focused ultrasound (FUS) protocol, utilizing living rats with jugular vein catheterization to monitor blood-brain barrier (BBB) opening.

The brain has a highly selective semipermeable blood barrier, termed the blood-brain barrier (BBB), which prevents the delivery of therapeutic ...

Neuronavigated tDCS for Enhanced Electrode Placement Accuracy in fMRI Studies

Neuronavigated Focalized Transcranial Direct Current Stimulation Administered During Functional Magnetic Resonance Imaging

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that allows the modulation of the excitability and plasticity of the human brain. Focalized tDCS setups use specific electrode arrangements to constrain the current flow to circumscribed brain regions. However, the effectiveness of focalized tDCS can be compromised by electrode positioning errors on the scalp, resulting in significant reductions of the current dose reaching the target brain regions for tDCS. Electrode placement guided by neuronavigation based on the individual&#39;s head and brain anatomy derived from structural magnetic resonance imaging (MRI) data may be suited to improve positioning accuracy.
This protocol describes the method of neuronavigated electrode placement for a focalized tDCS setup, which is suitable for concurrent administration during functional MRI (fMRI). We also quantify the accuracy of electrode placement and investigate electrode drift in a concurrent tDCS-fMRI experiment. Critical steps involve the optimization of electrode positions based on current modeling that considers the individual&#39;s head and brain anatomy, the implementation of neuronavigated electrode placement on the scalp, and the administration of optimized and focal tDCS during fMRI.
The regional precision of electrode placement is quantified using the Euclidean norm (L2&#160;Norm) to determine deviations of the actual from the intended electrode positions during a concurrent tDCS-fMRI study. Any potential displacement of electrodes (drift) during the experiment is investigated by comparing actual electrode positions before and after the fMRI acquisition. In addition, we directly compare the placement accuracy of neuronavigated tDCS to that achieved by a scalp-based targeting approach (a 10-20 Electroencephalography (EEG) system). These analyses demonstrate superior placement accuracy for neuronavigation compared to scalp-based electrode placement and negligible electrode drift across a 20 min scanning period.

This protocol describes the method of neuronavigated electrode placement for focal, transcranial direct current stimulation (tDCS) administered during functional magnetic resonance imaging (fMRI).

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that allows the modulation of the excitability and plasticity ...

Standardizing PoC TCCD Ultrasound Protocols for Critical Care in Adults

Point of Care Transcranial Color-Coded Duplex Ultrasound of the Middle Cerebral Artery

In the assessment and management of many clinical problems, point-of-care (PoC) ultrasound is an emerging bedside tool. Transcranial color-coded duplex (TCCD) ultrasound can be valuable in multiple situations, including for patients who are unconscious or have an equivocal neurologic examination, as it helps rule in specific intracranial pathologies. Despite the known diagnostic value of transcranial ultrasound, its use in critical care medicine remains variable. This variability is partly due to inconsistent training across hospitals, stemming from a lack of standardized education and training. Additionally, the brain has often been overlooked in many critical care protocols, such as RUSH (Rapid Ultrasound for Shock and Hypotension) and FAST (Focused Assessment with Sonography in Trauma) exams. To address these gaps, this article proposes a protocol for PoC TCCD image acquisition in adults, detailing indications, limitations, transducer selection, placement, sequence acquisition, and image optimization. Furthermore, the use of PoC TCCD is discussed as a means of screening for three conditions: vasospasm, raised intracranial pressure, and progression of cerebral circulatory arrest.

Transcranial ultrasound is an essential tool for monitoring patients with various neurological conditions. Although it is commonly used in a protocolized fashion in consultative studies, the brain has been overlooked in many protocols utilizing point-of-care ultrasound (PoCUS). This study proposes a PoCUS image acquisition protocol.

In the assessment and management of many clinical problems, point-of-care (PoC) ultrasound is an emerging bedside tool. Transcranial color-coded duplex ...

An Experimental Protocol for Assessing the Performance of New Ultrasound Probes Based on CMUT Technology in Application to Brain Imaging

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