Happening @ Michigan https://events.umich.edu/list/rss RSS Feed for Happening @ Michigan Events at the University of Michigan. PhD Defense: Josiah Simeth (August 5, 2020 2:00pm) https://events.umich.edu/event/75278 75278-19402991@events.umich.edu Event Begins: Wednesday, August 5, 2020 2:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Notice: This event will be held via BlueJeans. The link will be placed below.

BlueJeans: https://bluejeans.com/715371816

Measures of regional and global liver function are critical in guiding treatments for intrahepatic cancers, and liver function is a dominant factor in the survival of patients with hepatocellular carcinoma (HCC). Global and regional liver function assessments are important for defining the magnitude and spatial distribution of radiation dose to preserve functional liver parenchyma and reduce incidence of hepatotoxicity from radiation therapy (RT) for intrahepatic cancer treatment. This individualized liver function-guided RT strategy is critical for patients with heterogeneous and poor liver function, often observed in cirrhotic patients treated for HCC. Dynamic gadoxetic-acid enhanced (DGAE) magnetic resonance imaging (MRI) allows investigation of liver function through observation of the uptake of contrast agent into the hepatocytes.

This work seeks to determine if gadoxetic uptake rate can be used as a reliable measure of liver function, and to develop robust methods for uptake estimation with an interest in the therapeutic application of this knowledge in the case of intrahepatic cancers. Since voxel-by voxel fitting of the preexisting nonlinear dual-input two-compartment model is highly susceptible to over fitting, and highly dependent on data that is both temporally very well characterized and low in noise, this work proposes and validates a new model for quantifying the voxel-wise uptake rate of gadoxetic acid as a measure of regional liver function. This linearized single-input two-compartment (LSITC) model is a linearization of the pre-existing dual-input model but is designed to perform uptake quantification in a more robust, computationally simpler, and much faster manner. The method is validated against the preexisting dual-input model for both real and simulated data. Simulations are used to investigate the effects of noise as well as issues related to the sampling of the arterial peak in the characteristic input functions of DGAE MRI.

Further validation explores the relationship between gadoxetic acid uptake rate and two well established global measures of liver function, namely: Indocyanine Green retention (ICGR) and Albumin-Bilirubin (ALBI) score. This work also establishes the relationships between these scores and imaging derived measures of whole liver function using uptake rate. Additionally, the same comparisons are performed for portal venous perfusion, a pharmacokinetic parameter that has been observed to correlate with function, and has been used as a guide for individualized liver function-guided RT. For the patients assessed, gadoxetic acid uptake rate performs significantly better as a predictor of whole liver function than portal venous perfusion.
This work also investigates the possible gains that could be introduced through use of gadoxetic uptake rate maps in the creation of function-guided RT plans. To this end, plans were created using both perfusion and uptake, and both were compared to plans that did not use functional guidance. While the plans were generally broadly similar, significant differences were observed in patients with severely compromised uptake that did not correspond with compromised perfusion.

This dissertation also deals with the problem of quantifying uptake rate in suboptimal very temporally sparse or short DGAE MRI acquisitions. In addition to testing the limits of the LSITC model for these limited datasets (both realistic and extreme), a neural network-based approach to quantification of uptake rate is developed, allowing for increased robustness over current models.

Chair: Dr. Yue Cao

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Lecture / Discussion Thu, 23 Jul 2020 17:51:41 -0400 2020-08-05T14:00:00-04:00 2020-08-05T15:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME Seminar Series: Ben Cosgrove (September 3, 2020 4:00pm) https://events.umich.edu/event/75894 75894-19623813@events.umich.edu Event Begins: Thursday, September 3, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:01:44 -0400 2020-09-03T16:00:00-04:00 2020-09-03T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Ranu Jung (September 10, 2020 4:00pm) https://events.umich.edu/event/75902 75902-19623820@events.umich.edu Event Begins: Thursday, September 10, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 13:36:24 -0400 2020-09-10T16:00:00-04:00 2020-09-10T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Jane Grande-Allen (September 24, 2020 4:00pm) https://events.umich.edu/event/75904 75904-19623822@events.umich.edu Event Begins: Thursday, September 24, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 13:53:40 -0400 2020-09-24T16:00:00-04:00 2020-09-24T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Gautam Parthasarathy (October 1, 2020 4:00pm) https://events.umich.edu/event/75905 75905-19623823@events.umich.edu Event Begins: Thursday, October 1, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 13:56:48 -0400 2020-10-01T16:00:00-04:00 2020-10-01T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Nathan Price (October 8, 2020 4:00pm) https://events.umich.edu/event/75906 75906-19623824@events.umich.edu Event Begins: Thursday, October 8, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:01:08 -0400 2020-10-08T16:00:00-04:00 2020-10-08T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Tyrone Porter (October 22, 2020 4:00pm) https://events.umich.edu/event/75907 75907-19623825@events.umich.edu Event Begins: Thursday, October 22, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:06:51 -0400 2020-10-22T16:00:00-04:00 2020-10-22T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Sudin Bhattacharya (October 29, 2020 4:00pm) https://events.umich.edu/event/75908 75908-19623826@events.umich.edu Event Begins: Thursday, October 29, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:09:37 -0400 2020-10-29T16:00:00-04:00 2020-10-29T17:00:00-04:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Lori Setton (November 5, 2020 4:00pm) https://events.umich.edu/event/75909 75909-19623827@events.umich.edu Event Begins: Thursday, November 5, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:14:30 -0400 2020-11-05T16:00:00-05:00 2020-11-05T17:00:00-05:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME PhD Defense: Zhonghua (Aileen) Ouyang (November 6, 2020 10:00am) https://events.umich.edu/event/78398 78398-20022735@events.umich.edu Event Begins: Friday, November 6, 2020 10:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

NOTICE: This event will be held via Zoom. The link will be provided below.

Zoom: https://umich-health.zoom.us/j/94734899583?pwd=MDNEMjE3QU5xVGgwZzNQajE4UlJQUT09

Overactive bladder (OAB) is a highly prevalent condition which negatively affects the physical and mental health of millions of people worldwide. Sacral neuromodulation (SNM), currently serving ~300,000 patients worldwide, is a promising third-line therapy that provides improved efficacy and minimum adherence issue compared to conventional treatments. While current SNM is delivered in an open-loop fashion, the therapy could have improved clinical efficacy by adopting a closed-loop stimulation paradigm that uses objective physiological feedback. Therefore, this dissertation work focuses on using sacral level dorsal root ganglia neural signals to provide sensory feedback for adaptive SNM a feline model.

This work began with exploring machine learning algorithms and feature selection methods for bladder pressure decoding. A Kalman filter delivered the highest performance based on correlation coefficient between the pressure measurements and algorithm estimation. Additionally, firing rate normalization significantly contributed to lowering the normalized error, and a correlation coefficient-based channel selection method provided the lowest error compared to other channel selection methods.

Following algorithm optimization, this work implemented the optimized algorithm and feature selection method in real-time in anesthetized healthy and simulated OAB feline models. A 0.88 ± 0.16 correlation coefficient fit was achieved by the decoding algorithm across 35 normal and simulated OAB bladder fills in five experiments. Closed-loop neuromodulation was demonstrated using the estimated pressure to trigger pudendal nerve stimulation, which increased bladder capacity by 40% in two trials.

Finally, closed-loop SNM stimulation with DRG sensory feedback was performed in a series of anesthetized experiments. It increased bladder capacity by 13.8% over no stimulation (p < 0.001). While there was no statistical difference in bladder capacity between closed-loop and continuous stimulation (p = 0.80), closed-loop stimulation reduced stimulation time by 57.7%. Interestingly, bladder single units had a reduced sensitivity during stimulation, suggesting a potential mechanism of SNM.

Overall, this work demonstrated that sacral level DRG are a viable sensory feedback target for adaptive SNM. Validation in awake and chronic experiments is a crucial step prior to clinical translation of this method.

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Lecture / Discussion Fri, 09 Oct 2020 22:08:12 -0400 2020-11-06T10:00:00-05:00 2020-11-06T11:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME Seminar Series: Eytan Ruppin (November 12, 2020 4:00pm) https://events.umich.edu/event/75910 75910-19623828@events.umich.edu Event Begins: Thursday, November 12, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:22:54 -0400 2020-11-12T16:00:00-05:00 2020-11-12T17:00:00-05:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Maciek Antoniewicz (November 19, 2020 4:00pm) https://events.umich.edu/event/75911 75911-19623829@events.umich.edu Event Begins: Thursday, November 19, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:25:40 -0400 2020-11-19T16:00:00-05:00 2020-11-19T17:00:00-05:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
BME Seminar Series: Jae-Won Shin (December 3, 2020 4:00pm) https://events.umich.edu/event/75912 75912-19623830@events.umich.edu Event Begins: Thursday, December 3, 2020 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for our virtual seminar series on Thursdays from 4-5pm!
These events will take place on BlueJeans at this link: https://bluejeans.com/628109990

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Workshop / Seminar Thu, 20 Aug 2020 14:28:28 -0400 2020-12-03T16:00:00-05:00 2020-12-03T17:00:00-05:00 Off Campus Location Biomedical Engineering Workshop / Seminar BME
PhD Defense: Sabrina Lynch (December 15, 2020 10:00am) https://events.umich.edu/event/79855 79855-20509613@events.umich.edu Event Begins: Tuesday, December 15, 2020 10:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

NOTICE: This event will be held via Zoom. The link will be provided below.

Zoom link: https://umich-health.zoom.us/j/94668154127

Thrombosis is a process whereby a blood clot forms in situ within a vessel and impedes flow. Although necessary to maintain hemostasis, the human thrombotic system often becomes unstable leading to scenarios of thrombosis and subsequent diseases such as myocardial infarction, stroke, pulmonary embolism, and deep vein thrombosis. Computational modeling is a powerful tool to understand the complexity of thrombosis initiation and provides both temporal and spatial resolution that cannot be obtained in vivo. The goal of this investigation is to develop a computational model of thrombosis initiation in patient-specific models that includes both a complex description of the hemodynamics and biochemistry of thrombin formation. We argue that the complex hemodynamics occurring in vivo significantly alter the initiation and progression of thrombosis.



While blood viscosity is known to exhibit nonlinear behavior, a Newtonian assumption is often employed in computational analyses. This assumption is valid in healthy arteries where shear rates are high and recirculation is low. However, in pathological geometries, such as aneurysms, and venous geometries, this assumption fails, and nonlinear viscous effects become exceedingly important. Previous computational models of thrombosis have investigated coagulation through chemistry based formulations focusing on protein dynamics but have generally excluded complex 3D hemodynamics.



A computational framework was developed to investigate the interplay between 3D hemodynamics and the biochemical reactions involved in thrombosis initiation in patient-specific models under transient flow. The salient features of the framework are: i) nonlinear rheological models of blood flow; ii) a stabilized numerical framework for scalar mass transport; and iii) a computational interface for nonlinear scalar models of protein dynamics that can be easily customized to include an arbitrary number of species and protein interactions.



We implemented and verified nonlinear rheological models of viscosity into CRIMSON and investigated the effects of non-Newtonian viscosity on both hemodynamic and transport metrics in an arterial and venous patient-specific model. Results demonstrated the importance of considering accurate rheological models.



A stabilized finite element (FE) framework was developed to solve scalar mass transport problems in CRIMSON. Simulation of cardiovascular scalar mass transport problems offers significant numerical challenges such as highly advective flows and flow reversal at outlet boundaries. Furthermore, little attention has been given to the identification of appropriate outflow boundary conditions that preserve the accuracy of the solution. These issues were resolved by developing a stabilized FE framework that incorporates backflow stabilization for Neumann outlet boundaries; a consistent flux boundary condition that minimally disturbs the local physics of the problem; and front-capturing stabilization to regularize solutions in high Pe number flows. The efficacy of these formulations was investigated for both idealized and patient-specific geometries.



Next, a flexible arbitrary reaction-advection-diffusion (ARAD) interface was implemented that enables prototyping nonlinear biochemical models of thrombin generation. After verifying the ARAD interface, the performance was compared against the original hardcoded FORTRAN implementation for speed and accuracy using a 4-scalar nonlinear reaction model of thrombosis. Three different biochemical models of thrombin generation were investigated in idealized geometries. Finally, we implemented the 18 scalar model in both idealized and patient-specific geometries to determine the effects of complex 3D hemodynamics on thrombin generation.



The computational framework for thrombosis initiation presented in this work has three key features: i) non-Newtonian hemodynamics; ii) a stabilized numerical framework for scalar RAD problems; and iii) a method to rapidly prototype custom reaction models using Python with negligible associated computational expense.

Chair: Prof. Alberto C. Figueroa

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Lecture / Discussion Thu, 10 Dec 2020 12:16:10 -0500 2020-12-15T10:00:00-05:00 2020-12-15T11:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: Jared Scott (December 22, 2020 2:00pm) https://events.umich.edu/event/79866 79866-20509634@events.umich.edu Event Begins: Tuesday, December 22, 2020 2:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

NOTICE: This event will be held via Zoom. The link will be placed below.

https://umich-health.zoom.us/j/97604985906?pwd=N1Y1UXEvNXMxdjlnVkpjUFZHQkRhdz09

Epilepsy is a debilitating neurological disorder characterized by recurrent spontaneous seizures. While seizures themselves adversely affect physiological function for short time periods relative to normal brain states, their cumulative impact can significantly decrease patient quality of life in myriad ways. For many, anti-epileptic drugs are effective first-line therapies. One third of all patients do not respond to chemical intervention, however, and require invasive resective surgery to remove epileptic tissue. While this is still the most effective last-line treatment, many patients with ‘refractory’ epilepsy still experience seizures afterward, while some are not even surgical candidates. Thus, a significant portion of patients lack further recourse to manage their seizures – which additionally impacts their quality of life.



High-frequency oscillations (HFOs) are a recently discovered electrical biomarker with significant clinical potential in refractory human epilepsy. As a spatial biomarker, HFOs occur more frequently in epileptic tissue, and surgical removal of areas with high HFO rates can result in improved outcomes. There is also limited preliminary evidence that HFOs change prior to seizures, though it is currently unknown if HFOs function as temporal biomarkers of epilepsy and imminent seizure onset. No such temporal biomarker has ever been identified, though if it were to exist, it could be exploited in online seizure prediction algorithms. If these algorithms were clinically implemented in implantable neuromodulatory devices, improvements to quality of life for refractory epilepsy patients might be possible. Thus, the overall aim of this work is to investigate HFOs as potential temporal biomarkers of seizures and epilepsy, and further to determine whether their time-varying properties can be exploited in seizure prediction.



In the first study we explore population-level evidence for the existence of this temporal effect in a large clinical cohort with refractory epilepsy. Using sophisticated automated HFO detection and big-data processing techniques, a continuous measure of HFO rates was developed to explore gradual changes in HFO rates prior to seizures, which were analyzed in aggregate to assess their stereotypical response. These methods resulted in the identification of a subset of patients in whom HFOs from epileptic tissue gradually increased before seizures.



In the second study, we use machine learning techniques to investigate temporal changes in HFO rates within individuals, and to assess their potential usefulness in patient-specific seizure prediction. Here, we identified a subset of patients whose predictive models sufficiently differentiated the preictal (before seizure) state better than random chance.



In the third study, we extend our prediction framework to include the signal properties of HFOs. We explore their ability to improve the identification of preictal periods, and additionally translate their predictive models into a proof-of-concept seizure warning system. For some patients, positive results from this demonstration show that seizure prediction using HFOs could be possible.



These studies overall provide convincing evidence that HFOs can change in measurable ways prior to seizure start. While this effect was not significant in some individuals, for many it enabled seizures to be predicted above random chance. Due to data limitations in overall recording duration and number of seizures captured, these findings require further validation with much larger high-density intracranial EEG datasets. Still, they provide a preliminary framework for the eventual use of HFOs in patient-specific seizure prediction with the potential to improve the lives of those with refractory epilepsy.

Chair: Dr. William Stacey

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Lecture / Discussion Thu, 10 Dec 2020 14:13:29 -0500 2020-12-22T14:00:00-05:00 2020-12-22T15:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: Tianrui Luo (December 22, 2020 3:00pm) https://events.umich.edu/event/79858 79858-20509623@events.umich.edu Event Begins: Tuesday, December 22, 2020 3:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

NOTICE: This event will be held via Zoom. The link will be placed below.

https://umich.zoom.us/j/92217348735

Excitation pulse design and image reconstruction are two important topics in MR research for enabling faster imaging. On the pulse design side, selective excitations that confine signals to be within a small region-of-interest (ROI) instead of the full imaging field-of-view (FOV) can be used to reduce sampling density in the k-space, which is a direct outcome of the change in the underlying Nyquist sampling rate. On the reconstruction side, besides improving imaging algorithms’ ability to restore images from less data, another objective is to reduce the reconstruction time, particularly for dynamic imaging applications.



This dissertation focuses on these two perspectives: The first part is devoted to the excitation pulse design. Specifically, we derived and developed a computationally efficient auto-differentiable Bloch-simulator and its explicit Bloch simulation Jacobian operations. This simulator can yield numerical derivatives with respect to pulse RF and gradient waveforms given arbitrary subdifferentiable excitation objective functions. We successfully applied this pulse design approach for jointly designing RF and gradient waveforms for 3D spatially tailored large-tip excitation objectives.



The auto-differentiable pulse design method can yield superior 3D spatially tailored excitation profiles that are useful for inner volume (IV) imaging. We propose and develop a novel steady-state IV imaging strategy which suppresses aliasing by saturating the outer volume (OV) magnetizations via a 3D tailored OV excitation pulse that is followed by a signal crusher gradient. This method substantially suppresses the unwanted OV aliasing for common steady-state imaging sequences.



The second part focuses on non-iterative image reconstruction. In dynamic imaging (e.g., fMRI), where a time series is to be reconstructed, such algorithms may offer savings in overall reconstruction time. We extend the conventional GRAPPA algorithm to work efficiently for general non-Cartesian acquisitions. It attains reconstruction quality that can rival classical iterative imaging methods such as conjugate gradient SENSE and SPIRiT.



In summary, this dissertation has proposed and developed multiple methods for accelerating MR imaging, from pulse design to reconstruction. While devoted to neuroimaging, the proposed methods are general and should also be useful for other applications.

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Lecture / Discussion Thu, 10 Dec 2020 12:29:18 -0500 2020-12-22T15:00:00-05:00 2020-12-22T16:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Aaron Morris, Ph.D. (January 28, 2021 4:00pm) https://events.umich.edu/event/81261 81261-20879893@events.umich.edu Event Begins: Thursday, January 28, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

NOTICE: This event will be held via Zoom. The link will be posted below.
https://umich.zoom.us/j/94405051853

Seminar Abstract:

My research program, the Precision Immune Microenvironment (PIM) Lab, will create a minimally invasive toolset for monitoring immune responses within tissues. In my research seminar I will begin by briefly discussing the work I performed with Dr. Themis Kyriakides as a PhD student at Yale - strategies to manipulate the early stages of the foreign body response (FBR) to implanted materials. I will next discuss my work as a postdoctoral fellow at the University of Michigan with Dr. Lonnie Shea. I focus on harnessing the chronic phase of the FBR, as a tool to monitor the immune system. I use biomaterial-based immunological niches to provide insights into the phenotype of innate immune cells that control disease activity. Cells harvested from these niches exhibit differential gene expression sufficient to monitor disease dynamics and to gauge the effectiveness of treatment. I will then discuss work developing sensors for secreted proteins to non-invasively measure protein expression in vivo via luminescence and FRET. I will conclude my talk with a brief discussion of my planned research
program that aims to leverage my materials and immune engineering experience to harness bio-responsive materials as translatable tools for real-time monitoring of tissue immunity.

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Lecture / Discussion Tue, 26 Jan 2021 12:39:22 -0500 2021-01-28T16:00:00-05:00 2021-01-28T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Maria Coronel (February 4, 2021 4:00pm) https://events.umich.edu/event/81382 81382-20889813@events.umich.edu Event Begins: Thursday, February 4, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

BME Faculty Candidate
Maria Coronel, Ph.D.
Georgia Institute of Technology

Seminar Abstract:
Two major challenges to the translation of cellular-based tissue-engineered therapies are the lack of adequate oxygen support post-implantation and the need for systemic immunosuppression to halt the strong inflammatory and immunological response of the host. As such, strategies that aim at addressing oxygen demand, and local immunological responses can be highly beneficial in the translation of these therapies. In this seminar, I will focus on two biomaterial strategies to create a more favorable transplant niche for pancreatic islet transplantation. The first half will describe an in-situ oxygen-releasing biomaterial fabricated through the incorporation of solid peroxides in a silicone polymer. The implementation of this localized, controlled and sustained oxygen-generator mitigates the activation of detrimental hypoxia-induced pathways in islets and enhances the potency of extrahepatic 3D islet- loaded devices in a diabetic animal model. In the second part, I will focus on engineering synthetic biomaterials for the delivery of immunomodulatory signals for transplant acceptance. Biomaterial carriers fabricated with polyethylene glycol microgels are used to deliver immunomodulatory signals to regulate the local microenvironment and prevent allograft rejection in a clinically relevant pre-clinical transplant model. The use of synthetic materials as an off-the-shelf platform, without the need for manipulating the biological cell product, improves the clinical translatability of this engineered approach. Designing safer, responsive biomaterials to boost the delivery of targeted therapeutics will significantly reinvigorate interventional cell-based tissue-engineered therapies.

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Lecture / Discussion Fri, 29 Jan 2021 17:14:27 -0500 2021-02-04T16:00:00-05:00 2021-02-04T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Adam Glaser (February 18, 2021 4:00pm) https://events.umich.edu/event/81384 81384-20889815@events.umich.edu Event Begins: Thursday, February 18, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Seminar Abstract:

New developments in microscopy, tissue clearing, and fluorescent labeling are enabling unprecedented access to the structural and molecular contents of biological tissues. These technologies are now opening new doors in scientific research and shedding light on the critical factors which underpin complex disease processes. In this presentation, I will present my recent work in these areas, with a focus on applications to cancer at both the clinical and preclinical level.

ZOOM LINK: https://umich.zoom.us/j/94405051853

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Lecture / Discussion Sat, 13 Feb 2021 20:04:17 -0500 2021-02-18T16:00:00-05:00 2021-02-18T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Jorge Marchand (February 25, 2021 4:00pm) https://events.umich.edu/event/81385 81385-20889816@events.umich.edu Event Begins: Thursday, February 25, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Seminar Abstract:

In living organisms, translation of genetic information by the ribosome transforms
the information embedded in DNA into actuating components, namely proteins. Though life itself is incredibly diverse at the macroscopic level, at the molecular level, all of life uses the same set of machinery for translation - 20 standard amino acid building blocks (with minor exceptions), transfer RNAs (tRNA), and ribosomes. The convergence and association of these interdependent biomolecules is neatly captured in a table known as the ‘standard genetic code’. Even after billions of years of genetic drift, the ‘standard genetic code’ has been largely refractory to change. In this talk, I will be discussing strategies and methods for building organisms that can make and use non-standard amino acids to make proteins with enhanced or expanded function.

ZOOM LINK: https://umich.zoom.us/j/94405051853

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Lecture / Discussion Sun, 21 Feb 2021 22:07:28 -0500 2021-02-25T16:00:00-05:00 2021-02-25T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Danielle Bassett (March 4, 2021 4:00pm) https://events.umich.edu/event/81388 81388-20889818@events.umich.edu Event Begins: Thursday, March 4, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

TBD

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Lecture / Discussion Wed, 27 Jan 2021 21:05:02 -0500 2021-03-04T16:00:00-05:00 2021-03-04T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: George Christ (March 11, 2021 4:00pm) https://events.umich.edu/event/81389 81389-20889819@events.umich.edu Event Begins: Thursday, March 11, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Despite the well-documented capability of skeletal muscle to repair, regenerate, and remodel following injury, there remain a multitude of diseases, disorders, and traumatic injuries that result in irrecoverable loss of muscle structure and function. For example, volumetric muscle loss (VML) injuries are characterized by a degree of composite muscle tissue loss so severe, that it exceeds the native ability of the muscle to repair, thereby resulting in permanent cosmetic and functional deficits to the limbs, neck, or face. These injuries significantly impact both the civilian and military populations. Current treatment for VML injury involves surgical muscle transfer, although these procedures are often associated with both poor engraftment and donor site morbidity, as well as incomplete cosmesis and functional recovery. Not surprisingly, this unmet medical need has stimulated research efforts to develop new technologies for treatment of VML injuries. Recent attention has focused on development of tissue engineering (TE)/regenerative medicine (RM) technologies to provide more effective treatment options for large scale muscle injuries. A variety of preclinical approaches have been tried that include implantation of synthetic and/or natural extracellular matrices/scaffolds/constructs at the site of VML injury, both with and without a cellular component. Extant data indicate that the inclusion of a cellular component generally leads to a greater degree of functional improvement. Consistent with these preclinical results, recent clinical studies for treatment of VML injury, solely with implanted decellularized extracellular matrix scaffolds, have provided evidence for modest functional recovery but with little de novo muscle tissue regeneration at the injury site. More recently, bio-printed tissue engineered constructs and their potential applications to treatment of VML injury have been reported in the literature. While these initial clinical and preclinical observations are encouraging for the TE/RM paradigm, full structural and functional recovery has yet to be achieved, and thus, there remains significant room for therapeutic advancement. To this end, I will describe our highly collaborative efforts to boost development and evaluation of a range of implantable regenerative therapeutics (biomaterials and tissue engineered constructs) in biologically relevant animal models. The overall goal is to increase the efficiency of clinical translation of TE/RM technologies capable of more complete functional recovery following repair of VML injury.

ZOOM LINK: https://umich.zoom.us/j/94405051853

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Lecture / Discussion Mon, 08 Mar 2021 11:13:19 -0500 2021-03-11T16:00:00-05:00 2021-03-11T17:00:00-05:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Daniel Rueckert (March 18, 2021 4:00pm) https://events.umich.edu/event/81390 81390-20889820@events.umich.edu Event Begins: Thursday, March 18, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Zoom Link: https://cwru.zoom.us/webinar/register/WN_tmHJ7ArQRyO01NN6SfYYtg

Hosted by Dr. Frederick Epstein

Seminar Abstract:
The talk will focus on the use of deep learning techniques for the discovery and quantification of clinically useful information from medical images. The talk will describe how deep learning can be used for the reconstruction of medical images from undersampled data, image super-resolution, image segmentation and image classification. It will also show the clinical utility of applications of deep learning for the interpretation of medical images in applications such as brain tumour segmentation, cardiac image analysis and applications in neonatal and fetal imaging. Finally, it will be discussed how deep learning may change the future of medical imaging. https://openbme.org/

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Lecture / Discussion Mon, 15 Mar 2021 14:07:10 -0400 2021-03-18T16:00:00-04:00 2021-03-18T17:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Warren L. Grayson (March 25, 2021 4:00pm) https://events.umich.edu/event/81391 81391-20889821@events.umich.edu Event Begins: Thursday, March 25, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Tissue engineering provides a viable means of regenerating bone and skeletal muscle tissues following injuries that lead to large volumetric defects. Our lab has developed advanced biomaterial and stem cell-based approaches to promote functional recovery following volumetric muscle loss and critical-sized craniofacial bone injuries. This presentation will focus on three areas of ongoing research: (1) I will present our lab’s efforts to regenerate vascularized and innervated skeletal muscle in mice including our recent studies using human pluripotent stem cells. (2) Recently, our group completed a study focused on designing biomaterials to guide bone regeneration in situ in minipigs using intraoperative protocols for combining autologous stem cells with 3D-printed scaffolds. (3) Understanding the interaction between vascular cells and osteoprogenitors is critical for developing effective treatment methods. I will describe recent studies in which we developed a quantitative imaging platform for characterizing the spatial relationships between cell populations in the native murine calvarium. https://openbme.org/

ZOOM LINK TO REGISTER: https://cwru.zoom.us/webinar/register/WN_Kgyl3yf4TcKvlk9xNKluhA

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Lecture / Discussion Sun, 21 Mar 2021 17:46:23 -0400 2021-03-25T16:00:00-04:00 2021-03-25T17:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Tim Downing (April 1, 2021 4:00pm) https://events.umich.edu/event/81392 81392-20889822@events.umich.edu Event Begins: Thursday, April 1, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

https://openbme.org/

ZOOM LINK TO REGISTER: https://cwru.zoom.us/webinar/register/WN_iY_PMZevQwWRYkMyK7ifzA

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Lecture / Discussion Fri, 26 Mar 2021 14:01:59 -0400 2021-04-01T16:00:00-04:00 2021-04-01T17:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: James Collins (April 8, 2021 4:00pm) https://events.umich.edu/event/81393 81393-20889823@events.umich.edu Event Begins: Thursday, April 8, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

James Collins, Ph.D.
Massachusetts Institute of Technology

https://openbme.org/

ZOOM LINK TO REGISTER: https://cwru.zoom.us/webinar/register/WN_MSUiecgNTLyXR5bM8HSnR

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Lecture / Discussion Fri, 02 Apr 2021 15:01:39 -0400 2021-04-08T16:00:00-04:00 2021-04-08T17:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME 500 Seminar: Kelly J. Cross (April 15, 2021 4:00pm) https://events.umich.edu/event/81394 81394-20889824@events.umich.edu Event Begins: Thursday, April 15, 2021 4:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Join us for a virtual seminar series on topics related to race and science, technology, engineering and math (STEM) education. https://happenings.wustl.edu/event/an_honest_conversation_about_inequity_in_engineering#.YG9vT-hKhPY

Details:
DATE: Thursday, April 15, 2021
TIME: 4:00-5:00 PM
ZOOM LINK TO REGISTER: https://wustl.zoom.us/webinar/register/WN_NvH4qVTSRx2uSXbdW-eXNA

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Lecture / Discussion Wed, 14 Apr 2021 14:13:34 -0400 2021-04-15T16:00:00-04:00 2021-04-15T17:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME Master's Defense: Fatimah Alkaabi (April 16, 2021 12:00pm) https://events.umich.edu/event/83558 83558-21424731@events.umich.edu Event Begins: Friday, April 16, 2021 12:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

The central auditory system consists of the brain nuclei that transmit peripheral auditory nerve input to the auditory cortex for hearing perception. Damage to the auditory end organ, the cochlea, can result in hearing loss that drives the central auditory system to disarray causing disorders such as hyperacusis and tinnitus. These disorders can negatively affect patients’ quality of life. Tinnitus sufferers generally describe their tinnitus as a narrowband of sound that occurs in quiet, while hyperacusis sufferers express an exaggerated perception of sound level or intensity. These two disorders are often grouped together because tinnitus sufferers tend to report symptoms of hyperacusis and vice versa. However, hyperacusis and tinnitus do not always co-occur, suggesting that they have different neural origins. To study these conditions, researchers have induced cochlear damage in animal models, followed by behavioral and electrophysiological assessments. However, no study has adequately distinguished hyperacusis from tinnitus in individual animals. In this thesis, I detail the development of a novel hyperacusis and tinnitus assessment paradigm for individual animals using the pinna reflex combined with auditory brainstem responses (ABR). In the first chapter, I detail several enhancements to a computer system that ensures accurate sound presentation concurrently with capture of pinna reflex video data, as well as streamlines the subsequent data analysis. In the second chapter, the ABR, an evoked potential reflecting the summed electrical activity of cells in the auditory brainstem pathway, was assessed. Several studies suggest that ABR-wave characteristics might provide evidence of hyperacusis. ABRs were evoked using conventional and novel sound stimuli. They were then examined to look for possible indications of hyperacusis in noise overexposed guinea pigs. The present findings are discussed with several suggestions for future hyperacusis assessments.



Date: Friday, April 16, 2021

Time: 12:00 PM

Zoom: https://umich.zoom.us/j/91698183229

Chair: Dr. Susan Shore

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Lecture / Discussion Mon, 05 Apr 2021 23:04:39 -0400 2021-04-16T12:00:00-04:00 2021-04-16T13:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
Master's Defense: Annie Taylor (April 21, 2021 10:30am) https://events.umich.edu/event/83750 83750-21485477@events.umich.edu Event Begins: Wednesday, April 21, 2021 10:30am
Location: Off Campus Location
Organized By: Biomedical Engineering

Dopamine regulates motor performance and learning. Current models suggest that dopamine signals reward-prediction errors and/or movement vigor. These functions have been assessed predominantly using simple behavioral tasks. The role of dopamine in dexterous skill, however, is unknown. This question is important to understanding motor disorders such as Parkinson's Disease. Here we describe an experimental model to interrogate the role of dopamine release during learning and performance of dexterous skill. Fluorescent sensors dLight1.1 and GCaMP are used to monitor dopamine and calcium activity in the striatum and substantia nigra pars compacta (SNc) in rats performing skilled reaching tasks. Preliminary experiments have successfully recorded reward-associated signals in both striatum and SNc. Adaptations to the recording setup to facilitate long-term recording in larger rodents are described. These results demonstrate the viability of fiber photometry for measuring dopamine-related activity during skilled reaching tasks.



Date: Wednesday April 21, 2021

Time: 10:30 AM

Zoom: https://umich.zoom.us/j/96449273959

Chair: Dr. Dan Leventhal

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Lecture / Discussion Tue, 13 Apr 2021 15:34:29 -0400 2021-04-21T10:30:00-04:00 2021-04-21T11:30:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
Master's Defense: Ivo Cerda (April 30, 2021 10:00am) https://events.umich.edu/event/83915 83915-21612995@events.umich.edu Event Begins: Friday, April 30, 2021 10:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

Co-registering, chronic, and naturalistic assessments of the electrophysiological and behavioral features of the murine stress response can teach us how stress-behaviors are mechanistically driven by electrophysiological activity in neural circuits, how those relationships change over the course of the multi-week developing response to chronic ongoing stress, and how these changes ultimately contribute to the pathogenesis and progression of major depressive disorder and other psychiatric conditions. However, the long duration and multiplexed nature of the murine stress response have long been barriers to achieving such understandings. To address the need for technology that better captures the time progression of the murine stress response, we engineered the first-ever chronic recording system capable of gathering both behavioral and electrophysiological data in a naturalistic environment for freely-moving mice. Building from previous unpublished work at our lab, we first developed 16 units of a novel photointerrupter-based, Arduino-controlled digital phenotyping system capable of simultaneously recording 50+ behavioral metrics at a sub-second resolution continuously for weeks at a time. Subsequently, with the goal of assisting the concurrent exploration of brain mechanisms and behavior, we engineered a scaffold and cabling structure to support an ultra low-resistance commutator that allows chronic, multi-region brain electrophysiological recordings and integrated it into our digital behavioral phenotyping system. Our novel co-recording system is now fully operational and, along with allowing chronic electrophysiological recordings, supports measures of eating, drinking, food and sugary drink preference (a measure of anhedonia), locomotor activity, sleep, and actigraphy, all the while using 24/7 video tracking to allow detailed classification of behaviors at sub-second resolution. The system is also compatible with standard assessments in the field, including daily weight and fur checks. To demonstrate the duration of its co-recording capabilities, we implanted a cohort of mice with electrodes in three brain regions involved in the murine stress response – olfactory bulb, dorsal hippocampus, and medial prefrontal cortex – and recorded for five weeks. This is the first system to ever produce highly dense behavioral and electrophysiological data simultaneously and continuously over such a period of time.


Details:
DATE: Friday, April 30, 2021
TIME: 10:00 am - 12:00 pm
LOCATION: Zoom https://umich.zoom.us/j/93571968494)
Chair Committee: Brendon Watson, Tim Bruns, Cindy Chestek

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Lecture / Discussion Thu, 29 Apr 2021 20:12:17 -0400 2021-04-30T10:00:00-04:00 2021-04-30T12:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
BME Commencement 2021 (May 1, 2021 3:30pm) https://events.umich.edu/event/83890 83890-21595415@events.umich.edu Event Begins: Saturday, May 1, 2021 3:30pm
Location: Off Campus Location
Organized By: Biomedical Engineering

PLEASE MAKE SURE TO RSVP WITH THE LINK!

BME COMMENCEMENT CEREMONY
SATURDAY, MAY 1, 2021 | 3:30 PM EDT


COMMENCEMENT CEREMONY
ZOOM @ (3:30 PM)

AFTER PARTY
Spatial Chat @ (~4:30 PM)
(AFTER THE CEREMONY)

PROGRAM
Welcome & Introduction | Lonnie Shea Ph.D.
Program Chair Remarks | Rachael Schmedlen, Ph.D., Jan Stegemann, Ph.D., & Tim Bruns, Ph.D.
Program Coordinator Remarks | Rachel Patterson & Maria Steele
Alumni Welcome and Congratulations | Scott Merz, Richard Youngblood, & Xiaotian Tan
Student Addresses | Dipra Debnath, Ivo Woldarsky, & Katy Norman
Announcing the Graduates | Melissa Wrobel Ph.D., Brendon Baker, Ph.D., James Weiland, Ph.D., & Tim Bruns, Ph.D.
Confirmation of Degrees | Lonnie Shea, Ph.D.
Congratulations and Closing | Lonnie Shea, Ph.D.
Virtual socializing & After Party | Come congratulate and socialize with your fellow graduates, families, professors, and friends following the BME Commencement Ceremony.

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Ceremony / Service Tue, 27 Apr 2021 15:09:45 -0400 2021-05-01T15:30:00-04:00 Off Campus Location Biomedical Engineering Ceremony / Service BME Logo
PhD Defense: Elissa Welle (May 7, 2021 10:00am) https://events.umich.edu/event/83883 83883-21587612@events.umich.edu Event Begins: Friday, May 7, 2021 10:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

Neural interfaces create a connection between neural structures in the body and external electronic devices. Brain-machine interfaces and bioelectric medicine therapies rely on the seamless integration of neural interfaces with the brain, nerves, or spinal cord. However, conventional neural interfaces cannot meet the demands of high channel count, signal fidelity, and signal longevity that these applications require.



In this thesis we characterized the damage resulting from conventional Utah arrays after multiple years of implantation in the cortex of a non-human primate. The neuron density around the electrode shanks was compared to the neuron density of nearby healthy tissue, finding a 73% loss in density around the electrodes. The explanted arrays were imaged and characterized for forms of electrode surface inconsistency. Coating cracks, tip breakage, and parylene cracks were the most common inconsistency. A significantly higher number of tip breakage and coating crack occurrences were found on the edges of the arrays as compared to the middle. In this work, we made clear the need for a minimally damaging alternative to the Utah electrode array.



Neural interfaces composed of carbon fiber electrodes, with a diameter of 6.8 microns, could enable a more seamless integration with the body. Previous work resulted in an array of individuated carbon fiber electrodes that could record reliably high signal-to-noise ratio neural signals from the brain for several months. However, the carbon fiber arrays were limited by only 30% of the electrodes recording neural signals, despite inducing very minimal inflammation. Additionally, it was relatively unknown if carbon fibers would make suitable long-term peripheral neural interfaces. Here, we illustrate the potential of carbon fiber electrodes to meet the needs of a variety of neural applications.



First, we optimized state-of-the-art carbon fiber electrodes to reliably record single unit electrophysiology from the brain. By analyzing the previous manufacturing process, the cause of the low recording yield of the carbon fiber arrays was identified as the consistency of the electrode tip. A novel laser cutting technique was developed to produce a consistent carbon fiber tip geometry, resulting in a near tripling of recording yield of high amplitude chronic neural signals. The longevity of the carbon fiber arrays was also addressed. The conventional polymer coating was compared against platinum iridium coating and an oxygen plasma treatment, both of which outperformed the polymer coating. In this work, we customized carbon fiber electrodes for reliable, long-term neural recording.



Secondly, we translated the carbon fiber technology from the brain to the periphery in an architecture appropriate for chronic implantation. The insertion of carbon fibers into the stiffer structures in the periphery is enabled by sharpening the carbon fibers. The sharpening process combines a butane flame to sharpen the fibers with a water bath to protect the base of the array. Sharpened carbon fibers recorded electrophysiology from the rat vagus nerve and feline dorsal root ganglia, both structures being important targets for bioelectric medicine therapies. The durability of carbon fibers was also displayed when partially embedded carbon fibers in medical-grade silicone withstood thousands of repeated bends without fracture. This work showed that carbon fibers have the electrical and structural properties necessary for chronic application.



Overall, this work highlights the vast potential of carbon fiber electrodes. Through this thesis, future brain-machine interfaces and bioelectric medicine therapies may utilize sub-cellular electrodes such as carbon fibers in medical applications.



Date: Friday, May 7, 2021

Time: 10:00 AM

Zoom: https://umich.zoom.us/j/95839545566 (Zoom link requires prior registration)

Chair: Dr. Cynthia Chestek

For Assistance or Questions
um-bme@umich.edu

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Lecture / Discussion Mon, 26 Apr 2021 17:03:39 -0400 2021-05-07T10:00:00-04:00 2021-05-07T11:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
2021 BME Symposium (May 10, 2021 12:00pm) https://events.umich.edu/event/82858 82858-21203302@events.umich.edu Event Begins: Monday, May 10, 2021 12:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

To register please see:
https://myumi.ch/r8GzZ

The 2021 BME symposium will showcase our work in the areas of Imaging, Neural Engineering, Regenerative Medicine, and Precision Health. The event will take place over two days in the afternoons of Monday, May 10, 12:00 PM - 5:00 PM, and Tuesday, May 11, 12:00 PM - 5:00 PM. Each afternoon will include faculty talks, mini student dissertations, a panel discussion, and student poster sessions.

The goal of this event is to bring together faculty and students affiliated with BME from all parts of campus as a step toward building the BME community and celebrating accomplishments through difficult times while having an eye toward the future.

Please sign up and join us!

2021 U-M BME Symposium



May 10, 2021: 12:00 PM - 5:00 PM


Imaging at UM

May 10, 2021 - 12:00pm - 1:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Doug Noll
12:00 - 12:15 - Zhongming Liu, “Preclinical MRI of brain-gut interactions”
12:15 - 12:30 - Nicole Seiberlich, “Translating Quantitative MRI to the Clinic”
12:30 - 12:45 - Yannis Paulus, “Multimodal Photoacoustic Microscopy, OCT, and Fluorescence Molecular and Cellular Imaging of the Retina”
12:45 - 1:05 - Student Dissertations
1:05 - 1:30 - Panel Discussion - “The Future of Imaging Research at Michigan” - Vikas Gulani, Jeff Fessler, Cheri Deng, Zhen Xu, Xueding Wang


Neural Engineering at UM

May 10, 2021 - 2:00pm - 3:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Jim Weiland
2:00 - 2:15 - Kamran Diba, TBD
2:15 - 2:30 - Scott Lempka, TBD
2:30 - 2:45 - Deanna Gates, TBD
2:45 - 3:05 - Student Dissertations
3:05 - 3.30 - Panel Discussion - “The Science Fiction Future of Neural Engineering” - Cindy Chestek, Parag Patil, Tim Bruns, Bill Stacey


Poster Session: Imaging & Neural Engineering

May 10, 2021 - 4:00pm - 5:00pm
Location: Virtual/Spatial Chat

This poster session will give BME students a chance to present and discuss their research in the areas of Imaging and Neural Engineering.


May 11, 2021: 12:00 PM - 5:00 PM


Regenerative Medicine at UM

May 11, 2021 - 12:00pm - 1:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Lonnie Shea
12:00 - 12:15 - Carlos Aguilar, ”Understanding & Re-Writing Stem Cell Programs to Live Forever.”
12:15 - 12:30 - Idse Heemskerk, “Predicting cell fate from signaling history in human pluripotent stem cells”
12:30 - 12:45 - Ariella Shikanov, TBD
12:45 - 1:05 - Student Dissertations
1:05 - 1:30 - Panel Discussion - "Grand Challenges in Regenerative Medicine" - Dave Kohn


Precision Health at UM

May 11, 2021 - 2:00pm - 3:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: TBD
2:00 - 2:15 - Sriram Chandrasekharan, TBD
2:15 - 2: 30 - James Moon, TBD
2:30 - 2:45 - Deepak Nagrath, TBD
2:45 - 3:05 - Student Dissertations
3:05 - 3:30 - Panel Discussion - "Hope or Hype for Treating Diseases" - James Moon, Sriram Chandrasekharan, Deepak Nagrath



Poster Session: Regenerative Medicine & Precision Health


May 11, 2021 - 4:00pm - 5:00pm
Location: Virtual/Spatial Chat


This poster session will give BME students a chance to present and discuss their research in the areas of Regenerative Medicine and Precision Health.

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Conference / Symposium Thu, 22 Apr 2021 13:38:37 -0400 2021-05-10T12:00:00-04:00 2021-05-10T17:00:00-04:00 Off Campus Location Biomedical Engineering Conference / Symposium BME Logo
2021 BME Symposium (May 11, 2021 12:00pm) https://events.umich.edu/event/82858 82858-21555869@events.umich.edu Event Begins: Tuesday, May 11, 2021 12:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

To register please see:
https://myumi.ch/r8GzZ

The 2021 BME symposium will showcase our work in the areas of Imaging, Neural Engineering, Regenerative Medicine, and Precision Health. The event will take place over two days in the afternoons of Monday, May 10, 12:00 PM - 5:00 PM, and Tuesday, May 11, 12:00 PM - 5:00 PM. Each afternoon will include faculty talks, mini student dissertations, a panel discussion, and student poster sessions.

The goal of this event is to bring together faculty and students affiliated with BME from all parts of campus as a step toward building the BME community and celebrating accomplishments through difficult times while having an eye toward the future.

Please sign up and join us!

2021 U-M BME Symposium



May 10, 2021: 12:00 PM - 5:00 PM


Imaging at UM

May 10, 2021 - 12:00pm - 1:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Doug Noll
12:00 - 12:15 - Zhongming Liu, “Preclinical MRI of brain-gut interactions”
12:15 - 12:30 - Nicole Seiberlich, “Translating Quantitative MRI to the Clinic”
12:30 - 12:45 - Yannis Paulus, “Multimodal Photoacoustic Microscopy, OCT, and Fluorescence Molecular and Cellular Imaging of the Retina”
12:45 - 1:05 - Student Dissertations
1:05 - 1:30 - Panel Discussion - “The Future of Imaging Research at Michigan” - Vikas Gulani, Jeff Fessler, Cheri Deng, Zhen Xu, Xueding Wang


Neural Engineering at UM

May 10, 2021 - 2:00pm - 3:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Jim Weiland
2:00 - 2:15 - Kamran Diba, TBD
2:15 - 2:30 - Scott Lempka, TBD
2:30 - 2:45 - Deanna Gates, TBD
2:45 - 3:05 - Student Dissertations
3:05 - 3.30 - Panel Discussion - “The Science Fiction Future of Neural Engineering” - Cindy Chestek, Parag Patil, Tim Bruns, Bill Stacey


Poster Session: Imaging & Neural Engineering

May 10, 2021 - 4:00pm - 5:00pm
Location: Virtual/Spatial Chat

This poster session will give BME students a chance to present and discuss their research in the areas of Imaging and Neural Engineering.


May 11, 2021: 12:00 PM - 5:00 PM


Regenerative Medicine at UM

May 11, 2021 - 12:00pm - 1:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: Lonnie Shea
12:00 - 12:15 - Carlos Aguilar, ”Understanding & Re-Writing Stem Cell Programs to Live Forever.”
12:15 - 12:30 - Idse Heemskerk, “Predicting cell fate from signaling history in human pluripotent stem cells”
12:30 - 12:45 - Ariella Shikanov, TBD
12:45 - 1:05 - Student Dissertations
1:05 - 1:30 - Panel Discussion - "Grand Challenges in Regenerative Medicine" - Dave Kohn


Precision Health at UM

May 11, 2021 - 2:00pm - 3:30pm
Location: Virtual/Zoom
Livestream Available (Visible After Registration)

Moderator: TBD
2:00 - 2:15 - Sriram Chandrasekharan, TBD
2:15 - 2: 30 - James Moon, TBD
2:30 - 2:45 - Deepak Nagrath, TBD
2:45 - 3:05 - Student Dissertations
3:05 - 3:30 - Panel Discussion - "Hope or Hype for Treating Diseases" - James Moon, Sriram Chandrasekharan, Deepak Nagrath



Poster Session: Regenerative Medicine & Precision Health


May 11, 2021 - 4:00pm - 5:00pm
Location: Virtual/Spatial Chat


This poster session will give BME students a chance to present and discuss their research in the areas of Regenerative Medicine and Precision Health.

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Conference / Symposium Thu, 22 Apr 2021 13:38:37 -0400 2021-05-11T12:00:00-04:00 2021-05-11T17:00:00-04:00 Off Campus Location Biomedical Engineering Conference / Symposium BME Logo
PhD Defense: Edward Peter Washabaugh IV (May 27, 2021 10:00am) https://events.umich.edu/event/84050 84050-21619709@events.umich.edu Event Begins: Thursday, May 27, 2021 10:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

Injuries to the neuromusculoskeletal systems often result in muscle weakness, abnormal coordination strategies, and gait impairments. Functional resistance training during walking—where a patient walks while a device increases loading on the leg—is an emerging approach to combat these symptoms. While simple passive devices (i.e., ankle weights and resistance bands) can be applied for this training, rehabilitation robots have more potential upside because they can be controlled to treat multiple gait abnormalities and can be monitored by clinicians. However, the cost of conventional robotic devices limits their use in the clinical or home setting. Hence, in this dissertation, we designed, developed, and tested passive and semi-passive wearable exoskeleton devices as a low-cost solution for providing controllable/configurable functional resistance training during walking.


We developed and tested two passive exoskeleton devices for providing resistance to walking and tested their effects on able-bodied participants and stroke survivors. First, we created a patented device that used a passive magnetic brake to provide a viscous (i.e., velocity-dependent) resistance to the knee. The resistive properties of the device could be placed under computer control (i.e., made semi-passive) to control resistance in real-time. Next, we created a passive exoskeleton that provided an elastic (i.e., position-dependent) resistance. While not controllable, this device was highly configurable. Meaning it could be used to provide resistance to joint flexion, extension, or to both (i.e., bidirectionally). Human subjects testing with these devices indicated they increased lower-extremity joint moments, powers, and muscle activation during training. Training also resulted in significant aftereffects—a potential indicator of therapeutic effectiveness—once the resistance was removed. A separate experiment indicated that individuals often kinematically slack (i.e., reduce joint excursions to minimize effort) when resistance is added to the limb. We also found that providing visual feedback of joint angles during training significantly increased muscle activation and kinematic aftereffects (i.e., reduced slacking).


With passive devices, the type of passive element used largely dictates the muscle groups, types of muscle contraction, joint actions, and the phases of gait when a device is able to apply resistance. To examine this issue, we compared the training effects of viscous and elastic devices that provided bidirectional resistance to the knee during gait. Additionally, we compared training with viscous resistances at the hip and knee joints. While the resistance type and targeted joint altered moments, powers, and muscle activation patterns, these methods did not differ in their ability to produce aftereffects, alter neural excitability, or induce fatigue in the leg muscles. While this may indicate that the resistance type does not have a large effect on functional resistance training during walking, it is possible that an extended training with these devices could produce a different result.


Lastly, we used musculoskeletal modeling in OpenSim to directly compare several strategies that have been used to provide functional resistance training to gait in the clinic or laboratory setting. We found that devices differed in their ability to alter gait parameters during walking. Hence, these findings could help clinicians when selecting a resistive strategy for their patients, or engineers when designing new devices or control schemes.



Date: Thursday, May 27, 2021

Time: 10:00 AM

Zoom: https://umich.zoom.us/meeting/register/tJIufumrrDgtHd3z5Jg3Y_BG4ZC70OPrjTjk (Zoom link requires prior registration)

Chair: Dr. Chandramouli Krishnan

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Lecture / Discussion Fri, 14 May 2021 13:49:26 -0400 2021-05-27T10:00:00-04:00 2021-05-27T11:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: William Y. Wang (June 4, 2021 12:30pm) https://events.umich.edu/event/84102 84102-21620248@events.umich.edu Event Begins: Friday, June 4, 2021 12:30pm
Location: Off Campus Location
Organized By: Biomedical Engineering

Mechanoreciprocity in cell migration is an emerging concept describing the dynamic, bi-directional interactions between migrating cells and the surrounding extracellular matrix (ECM) they negotiate. Migrating cells not only sense and adapt to biochemical and biophysical ECM cues, but also, exert forces, deposit matrix, and secrete chemokines, matrix metalloproteinases, and matrix crosslinking enzymes that dynamically alter the same ECM properties known to regulate cell migration. Due to limitations in standard cell migration assays, how matrix properties influence cell migration and in turn, how cells influence matrix properties, has previously been studied as separate processes. However, observations from development, wound healing, and a variety of disease processes highlight the interdependency and iterative relationship between cell migration and ECM. An improved understanding of the underlying mechanisms that orchestrate the coevolution of migrating cells and ECM will aid in tissue engineering and regenerative medicine efforts to guide repair fibroblasts to regenerate wound beds, direct collective endothelial cell migration to vascularize ischemic or engineered tissue grafts and confine otherwise metastatic cancer cells to the primary tumor. Thus, the focus of this dissertation is to design biomimetic microsystems that afford investigation of cell migration mechanoreciprocity with a focus on fibroblasts, endothelial cells, and cancer cells.



First, this thesis investigated how single mesenchymal cells (fibroblasts and cancer cells) migrate in fibrous stromal tissue settings, such as in trans-stromal cancer cell migration during metastasis. To model fibrous stromal tissue, 3D fiber networks were electrospun over microfabricated wells to define ECM mechanics. Independently tuning alignment and stiffness of these matrices resulted in two phenotypically distinct cell migration modes. In contrast to stiff matrices where cells migrated continuously in a traditional mesenchymal fashion, cells in deformable matrices stretched matrix fibers to store elastic energy; subsequent adhesion failure triggered sudden matrix recoil and rapid cell translocation (termed slingshot migration). Across a variety of cell types, traction force measurements revealed a relationship between cell contractility and the matrix stiffness where slingshot migration mode occurred optimally.



Next, this thesis describes how microenvironmental cues influence collective endothelial cell migration during sprouting angiogenesis towards the design of pro-angiogenic biomaterials. This work employed a multiplexed angiogenesis-on-a-chip platform to assess the chemokine-directed 3D invasion of endothelial cells from a lumenized parent vessel into user-defined ECM. By tuning soluble and physical cues of the ECM, this work identified how 1) functional angiogenesis requires microenvironmental cues that balance cell invasion speed and proliferation; 2) dynamic interactions between sprout stalk cells and ECM regulates neovessel lumenization; and 3) imbuing microporosity within synthetic hydrogels can enhance endothelial cell invasion and angiogenic sprout lumenization.



Lastly, this thesis investigated how fibrous matrix cues activate quiescent vessel-lining endothelial cells into invasive tip cells in the context of fibrosis. Composite hydrogels (electrospun fiber segments suspended within 3D ECM) were integrated with the angiogenesis-on-a-chip platform. These studies establish that heightened matrix fiber density destabilizes cell-cell adherens junctions, reduces endothelium barrier function, and promotes the invasion of endothelial tip cells. Performing transcriptomic and secretomic analyses on fiber-induced tip endothelial cells revealed that fibrous ECM cues promote a fibrosis propagating phenotype.



Overall, the work presented in this dissertation integrates tunable biomaterials with microfabricated devices to investigate cell migration mechanoreciprocity of single mesenchymal cell migration, the collective migration of endothelial cells during angiogenesis, and endothelial-mesenchymal transition of quiescent endothelial cells into a fibrosis propagating cell phenotype.



Date: Friday, June 4, 2021

Time: 12:30 PM

Zoom: https://umich.zoom.us/meeting/register/tJcsf-uhpj4vGtyM7x-td2VV39BzqmF_zoob (Zoom link requires prior registration)

Chair: Dr. Brendon Baker

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Lecture / Discussion Mon, 24 May 2021 14:17:02 -0400 2021-06-04T12:30:00-04:00 2021-06-04T13:30:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: Jiayue Cao (June 23, 2021 3:00pm) https://events.umich.edu/event/84287 84287-21621035@events.umich.edu Event Begins: Wednesday, June 23, 2021 3:00pm
Location: Off Campus Location
Organized By: Biomedical Engineering

The stomach and brain interact closely with each other. Their interactions are central to digestive functions and the “gut feeling”. The neural pathways that mediate the stomach-brain interactions include the vagus nerve and the thoracic nerve. Through these nerves, the stomach can relay neural signals to a number of brain regions that span a central gastric network. This gastric network allows the brain to monitor and regulate gastric physiology and allows the stomach to influence emotion and cognition. Impairment of this gastric network may lead to both gastric and neurological disorders, e.g., anxiety, gastroparesis, functional dyspepsia, and obesity. However, the structural constituents and functional roles of the central gastric network remain unclear. In my dissertation research, I leveraged complementary techniques to characterize the central gastric network in rats across a wide range of scales and different gastric states. In animal experiments, I used functional magnetic resonance imaging (fMRI) to map brain activity synchronized with gastric electrical activity and to map brain activations induced by electrical stimulation applied to the cervical vagus or its afferent terminals on the stomach. I also used neurophysiology to characterize gastric neurons in brainstem in response to gastric electrical stimulation. Results from my studies suggest that 1) gastric neurons in the brainstem are selective to the orientation of muscle activity relayed through intramuscular arrays, 2) the central gastric network is intrinsically coupled to gastric slow waves and their amplitude fluctuations primarily via vagal signaling, 3) selective stimulation of the vagus can evoke widespread and fast brain responses and alter functional connectivity within and beyond the central gastric network. My dissertation research contributes to the foundation of mapping and characterizing the central and peripheral mechanisms of gastric interoception and sheds new light on where and how to stimulate the peripheral nerves to modulate stomach-brain interactions.



Date: Wednesday, June 23, 2021

Time: 3:00 PM

Zoom: https://umich.zoom.us/j/2757414653

Chair: Dr. Zhongming Liu

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Lecture / Discussion Tue, 15 Jun 2021 23:04:33 -0400 2021-06-23T15:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: Eric Charles Hobson (June 24, 2021 10:30am) https://events.umich.edu/event/84237 84237-21620794@events.umich.edu Event Begins: Thursday, June 24, 2021 10:30am
Location: Off Campus Location
Organized By: Biomedical Engineering

Mechanical testing of viscoelastic biomaterials is of critical importance in biomedical engineering, enabling basic research into the role of the extracellular matrix, investigatory and diagnostic testing of tissues and biofluids, and the development and characterization of tissue engineered therapeutics. Conventional material testing approaches used for soft biomaterials generally require force application through direct contact with a sample, leading to potential contamination and damage, and thereby limiting these approaches to end-point measurements. To overcome these limitations, we have developed a new measurement technique, Resonant Acoustic Rheometry (RAR), which enables high-throughput, quantitative, and non-contact viscoelastic characterization of biomaterials, soft tissues, and biological fluids.



RAR uses ultrasonic pulses to both generate microscale perturbations and measure the resulting resonant oscillations at the surface of soft materials using standard labware. Resonant oscillatory properties obtained from the frequency spectra of the surface oscillations, including the resonant frequency and the damping coefficient, are used to quantify material properties such as shear modulus, shear viscosity, and surface tension in both viscoelastic solids and liquids.



We developed a prototype RAR system and tested it on a range of soft biomaterials, with shear moduli ranging from under 100 Pa to over 50 kPa, including fibrin, gelatin, and polyethylene glycol (PEG). Shear moduli measured using RAR were validated both computationally using finite element analysis and experimentally using conventional shear rheometry, with excellent linear correlation in measured elasticity between techniques (R2 > 0.95). By performing parallel RAR experiments using microwells of different sizes, we verified that resonant oscillatory behaviors could be used to quantify the intrinsic viscoelastic properties of a material. We also demonstrated the rapid, non-contact monitoring of changes in material properties over a variety of temporal scales, ranging from processes occurring on the order of milliseconds to those occurring over hours and days. High temporal resolution RAR measurements, with sampling intervals as low as 0.2 seconds, were used to characterize the gelation process. Characteristic features of the resonant surface waves during phase transition were applied to identify the gel point for various hydrogels. High sample throughput was demonstrated by performing longitudinal RAR testing to explore the impact of hydrogel polymer and crosslinker concentration on both reaction kinetics and final mechanical properties in full factorial experiments consisting of over 15,000 unique measurements. We were able to identify individual effects of design parameters as well as interactions that led to unexpected mechanical properties, demonstrating the importance of combinatorial methods and high-throughput mechanical characterization in material design.



These studies demonstrate that RAR can rapidly and accurately assess the mechanical properties of soft viscoelastic biomaterials. The measurements generated are analogous to those produced using conventional mechanical testing, and RAR is further capable of longitudinal viscoelastic studies over time. RAR applies automation in both data collection and analysis, allowing high throughput measurement of an array of samples without contact or the need for manual intervention. Furthermore, RAR uses standard microwell plates, which simplifies sample preparation and handling. The viscoelastic properties of soft biomaterials are relevant in a wide range of applications, including for clinical diagnostic assays and the development of hydrogel materials for regenerative medicine. RAR represents a fast, accurate, and cost-effective method for materials characterization in these applications.



June 24 - 10:30 AM

Zoom: https://umich.zoom.us/meeting/register/tJcsd-iurTosGdNn_gR-FbOCe5TUR09Y58WV

Co-Chairs: Dr. Cheri Deng and Dr. Jan Stegmann

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Lecture / Discussion Tue, 22 Jun 2021 16:37:33 -0400 2021-06-24T10:30:00-04:00 2021-06-24T11:30:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo
PhD Defense: Hans Zander (July 9, 2021 9:00am) https://events.umich.edu/event/84346 84346-21623406@events.umich.edu Event Begins: Friday, July 9, 2021 9:00am
Location: Off Campus Location
Organized By: Biomedical Engineering

Spinal cord stimulation (SCS) is a neuromodulation technique that applies electrical stimulation to the spinal cord to alter neural activity or processing. While SCS has historically been used as a last resort therapy for chronic pain management, novel applications and technologies have recently been developed that either increase the efficacy of treatment for chronic pain or drive neural activity to produce muscular activity/movement following a paralyzing spinal cord injury (SCI). Despite these recent innovations, there remain fundamental questions concerning the neural recruitment underlying these efficacious results. This work evaluated the neural activity and mechanisms for two novel SCS applications: closed-loop spinal cord stimulation for pain management, and ventral, high frequency spinal cord stimulation (HF-SCS) for inspiratory muscle activation following a SCI.

To evaluate neural activity, I developed computational models of SCS. Models consisted of 3 components: a finite element model (FEM) of the spinal cord to predict voltages during stimulation, biophysical neuron models, and algorithms to apply time-dependent extracellular voltages to the neuron models and simulate their response. While this cutting-edge modeling methodology could be used to predict neural activity following stimulation, it was unclear how common anatomical or technical model simplifications affected neural predictions. Therefore, the initial goal of this work was to evaluate how modeling assumptions influence neural behavior.

My initial work identified how several relevant anatomical and technical factors influence model predictions of neural activity. To evaluate these factors, I designed an FEM of a T9 thoracic spine with an implanted electrode. Then, I sequentially removed details from the model and quantified the changes in neural predictions. I identified several factors with profound (>30%) impacts on neural thresholds, including overall model impedance (for voltage-controlled stimulation), the presence of a detailed vertebral column, and dura mater conductivity. I also identified several factors that could safely be ignored in future models. This work will be invaluable as a guide for future model development.

Next, I developed a canine model to evaluate T2 ventral HF-SCS for inspiratory muscle activation. I designed and positioned two neuron models hypothesized to lead to inspiratory behavior: ventrolateral funiculus fibers (VLF) leading to diaphragm activation and inspiratory intercostal motoneurons. With this model, I predicted robust VLF and T2-T5 motoneuron recruitment within the physiologic range of stimulation. Additionally, I designed two stimulation leads that maximize inspiratory neuron recruitment. The finalized leads were evaluated via in vivo experiments, which found excellent agreement with the model. This work builds our mechanistic understanding of this novel therapy, improves its implementation, and aids in future translational efforts towards human subjects.

Finally, I developed a computational model to evaluate closed-loop stimulation for chronic pain. This work characterized the neural origins of the evoked compound action potential (ECAP), the controlling biomarker of closed-loop stimulation. I modified my modeling methodology to predict ECAPs generated during low thoracic dorsal stimulation in humans, which matched with experimental measurements. This modeling work showed that ECAP properties depend on activation of a narrow range of neuron diameters and quantified how anatomical and stimulation factors (CSF thickness, stimulation configuration, lead position, pulse width) influence ECAP morphology, timing, and neural recruitment. These results improve our mechanistic understanding of closed-loop stimulation and may lead to expanded clinical utility as well as better validation of future SCS computational models.

Date: Friday, July 9, 2021

Time: 9:00 AM EDT

Zoom: https://umich.zoom.us/j/96847307388

Chair: Dr. Scott Lempka

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Lecture / Discussion Tue, 22 Jun 2021 16:45:26 -0400 2021-07-09T09:00:00-04:00 2021-07-09T10:00:00-04:00 Off Campus Location Biomedical Engineering Lecture / Discussion BME Logo