TAAC - TMS Adaptable Auditory Control: a universal tool to mask TMS click

AbstractBackgroundCoupling transcranial magnetic stimulation with electroencephalography (TMS-EEG) allows recording the EEG response to a direct, non-invasive cortical perturbation. However, obtaining a genuine TMS-evoked EEG potential requires controlling for several confounds, among which a main source is represented by the auditory evoked potentials (AEPs) associated to the TMS discharge noise (TMS click). This contaminating factor can be in principle prevented by playing a masking noise through earphones.New methodHere we release TMS Adaptable Auditory Control (TAAC), a highly flexible, open-source, Matlab®-based interface that generates in real-time customized masking noises. TAAC creates noises starting from the stimulator-specific TMS click and tailors them to fit the individual, subject-specific click perception by mixing and manipulating the standard noises in both time and frequency domains.ResultsWe showed that TAAC allows us to provide standard as well as customized noises able to effectively and safely mask the TMS click.Comparison with existing methodsHere, we showcased two customized noises by comparing them to two standard noises previously used in the TMS literature (i.e., a white noise and a noise generated from the stimulator-specific TMS click only). For each, we quantified the Sound Pressure Level (SPL; measured by a Head and Torso Simulator - HATS) required to mask the TMS click in a population of 20 healthy subjects. Both customized noises were effective at safe (according to OSHA and NIOSH safety guidelines), lower SPLs with respect to standard noises.ConclusionsAt odds with previous methods, TAAC allows creating effective and safe masking noises specifically tailored on each TMS device and subject. The combination of TAAC with tools for the real-time visualization of TEPs can help control the influence of auditory confounds also in non-compliant patients. Finally, TAAC is a highly flexible and open-source tool, so it can be further extended to meet different experimental requirements.

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Silica-coated bismuth sulfide nanorods as multimodal contrast agents for a non-invasive visualization of the gastrointestinal tract

Nanoscale ◽

10.1039/c5nr03068d ◽

2015 ◽

Vol 7 (29) ◽

pp. 12581-12591 ◽

Cited By ~ 37

Author(s):

Xiaopeng Zheng ◽

Junxin Shi ◽

Yang Bu ◽

Gan Tian ◽

Xiao Zhang ◽

...

Keyword(s):

Gastrointestinal Tract ◽

Contrast Agents ◽

Real Time ◽

Bismuth Sulfide ◽

Non Invasive ◽

Real Time Visualization

In this paper we have prepared Bi2S3@SiO2 nanorods designed as binary contrast agents for a non-invasive and real-time visualization of the gastrointestinal tract.

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Dynamic tracking of a magnetic micro-roller using ultrasound phase analysis

10.21203/rs.3.rs-366904/v2 ◽

2021 ◽

Author(s):

Stefano Pane ◽

Veronica Iacovacci ◽

Mohammad Hasan Dad Ansari ◽

Arianna Menciassi

Keyword(s):

Real Time ◽

Average Error ◽

Contrast Resolution ◽

Low Contrast ◽

Non Invasive ◽

Dynamic Tracking ◽

Fine Control ◽

Real Time Visualization ◽

Acoustic Phase

Abstract Microrobots (MRs) have attracted significant interest for their potentialities in diagnosis and non-invasive intervention in hard-to-reach body areas. Fine control of biomedical MRs requires real-time feedback on their position and configuration. Ultrasound (US) imaging stands as a mature and advantageous technology for MRs tracking, but it suffers from disturbances due to low contrast resolution. To overcome these limitations and make US imaging suitable for monitoring and tracking MRs, we propose a US contrast enhancement mechanism for MR visualization in echogenic backgrounds (e.g., tissue). Our technique exploits the specific acoustic phase modulation produced by the MR characteristic motions. By applying this principle, we performed real-time visualization and position tracking of a magnetic MR rolling on a lumen boundary, both in static flow and opposing flow conditions, with an average error of 0.25 body-lengths. Overall, the reported results unveil countless possibilities to exploit the proposed approach as a robust feedback strategy for monitoring and tracking biomedical MRs in-vivo.

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Development of a 3D real-time visualization system for ship handling simulators using an open source 3D graphics engine

Journal of Navigation and Port Research ◽

10.5394/kinpr.2011.35.3.187 ◽

2011 ◽

Vol 35 (3) ◽

pp. 187-195 ◽

Cited By ~ 3

Author(s):

Tae-Hyun Fang ◽

Jae-Yong Oh ◽

Ho-Jin Hwang ◽

Byung-Chul Kim ◽

Du-Hwan Mun

Keyword(s):

Open Source ◽

Real Time ◽

3D Graphics ◽

Visualization System ◽

Real Time Visualization ◽

Graphics Engine ◽

Ship Handling

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Near Infra-Red Labelling and Tracking of Transplanted Corneal Endothelial Graft

10.21203/rs.3.rs-244628/v1 ◽

2021 ◽

Author(s):

Maninder Bhogal ◽

Heng-Pei Ang ◽

Shu-Jun Lin ◽

Lwin Chan ◽

Khadijah Adnan ◽

...

Keyword(s):

Real Time ◽

Corneal Transplantation ◽

Specular Microscopy ◽

Post Transplantation ◽

In Vivo Evaluation ◽

Non Invasive ◽

Real Time Visualization ◽

Donor Graft

Abstract Following corneal transplantation, there is an initial decline in corneal endothelial cells (CECs) following graft preparation and surgery. Monitoring post-transplantation is only possible months after surgery by specular microscopy, which has a limited field of view. We have developed a labelling approach using 1,1’-dioctadecyl-3,3,3’,3’-tetramethylindotricarbocyanine iodide (DIR) dye solution, that enabled tracking of labelled CECs in vivo for at least one month. Initial in vitro optimization of dye concentration, cellular toxicity and real-time cell migration was assessed using propagated primary CECs. Subsequent in vivo evaluation of cellular labelling was assessed within a rabbit wound healing model. Finally, real-time visualization of human cadaver donor tissue incubated in DIR transplanted into rabbits was achieved using the Heidelberg Spectralis. Results revealed detectable fluorescence increased with concentration to a plateau of 100µg/ml, with no toxicity of CECs at any concentration evaluated. DIR-labelled CECs were detectable in vivo upto 1 month, and transplanted labelled donor graft could be visualized and were trackable in vivo. Acute endothelial rejection in 1 rabbit was evidenced by detectable DIR positive cells within the anterior chamber. DIR imaging allowed for detailed imaging of the transplanted corneal endothelium, and enabled non-invasive observation of the corneal endothelial morphology following transplantation.

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Dynamic tracking of a magnetic micro-roller using ultrasound phase analysis

Scientific Reports ◽

10.1038/s41598-021-02553-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Stefano Pane ◽

Veronica Iacovacci ◽

Mohammad Hasan Dad Ansari ◽

Arianna Menciassi

Keyword(s):

Real Time ◽

Average Error ◽

Contrast Resolution ◽

Low Contrast ◽

Non Invasive ◽

Dynamic Tracking ◽

Fine Control ◽

Real Time Visualization ◽

Acoustic Phase

AbstractMicrorobots (MRs) have attracted significant interest for their potentialities in diagnosis and non-invasive intervention in hard-to-reach body areas. Fine control of biomedical MRs requires real-time feedback on their position and configuration. Ultrasound (US) imaging stands as a mature and advantageous technology for MRs tracking, but it suffers from disturbances due to low contrast resolution. To overcome these limitations and make US imaging suitable for monitoring and tracking MRs, we propose a US contrast enhancement mechanism for MR visualization in echogenic backgrounds (e.g., tissue). Our technique exploits the specific acoustic phase modulation produced by the MR characteristic motions. By applying this principle, we performed real-time visualization and position tracking of a magnetic MR rolling on a lumen boundary, both in static flow and opposing flow conditions, with an average error of 0.25 body-lengths. Overall, the reported results unveil countless possibilities to exploit the proposed approach as a robust feedback strategy for monitoring and tracking biomedical MRs in-vivo.

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Ultrasound-guided navigation of a magnetic microrobot using acoustic phase analysis

10.21203/rs.3.rs-366904/v1 ◽

2021 ◽

Author(s):

Stefano Pane ◽

Veronica Iacovacci ◽

Mohammad Hasan Dad Ansari ◽

Arianna Menciassi

Keyword(s):

Real Time ◽

Closed Loop ◽

Average Error ◽

Low Contrast ◽

Loop Control ◽

Non Invasive ◽

Fine Control ◽

Real Time Visualization ◽

Acoustic Phase

Abstract Microrobots (MRs) have attracted significant interest for their potentialities in diagnosis and non-invasive intervention in hard-to-reach body areas. Fine control of biomedical MRs requires real-time feedback on their position and configuration. Ultrasound (US) imaging stands as a mature and advantageous technology for MRs tracking, but it suffers from disturbances due to low contrast resolution. To overcome these limitations and make US imaging suitable for closed-loop MR control, we propose a US contrast enhancement mechanism for MR visualization in heterogeneous and dynamic backgrounds (e.g., tissue). Our technique exploits the specific acoustic phase modulation produced by the MR characteristic motions. By applying this principle, we performed real-time visualization and position tracking of a magnetic MR rolling on a lumen boundary, both in static flow and opposing flow conditions, with an average error of 0.25 body-lengths. Overall, the reported results unveil countless possibilities to exploit the proposed approach as a robust feedback strategy for closed-loop control of medical MRs in-vivo.

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