Miniaturization of electronics modules is always required for various medical applications including wearable technology, such as hearing aids, and implantable devices. Many types of high-density packaging technologies, such as package-on-package, bare-die stack, flex folded package and Through Si Via (TSV) technologies, have been proposed and used to fulfill the request. Among them, embedded die technology is one of the promising technologies to realize miniaturization and high-density packaging. We have developed WABE™ (wafer and board level device embedded) technology for embedding dies into multilayer flexible printed circuit (FPC) boards. The WABE package is comprised of thin dies (85 μm thickness), multi-layer polyimide, adhesive films and conductive paste. The dies are sandwiched by polyimide films with Cu circuits (FPCs). The conductive paste provides electrical connections between the layers as well as the layer and embedded die. First, each FPC layer is fabricated individually, and via holes are filled with conductive paste, and the dies are mounted on certain layers. Then, all layers undergo a one-step co-lamination process, and they are pressed to cure the adhesive material and conductive paste at the same time. This WABE technology has enabled multiple dies to be embedded by the one-step lamination process. Even if multiple dies are embedded, the footprint of a package can be reduced drastically by embedding multiple dies vertically in stacks. This paper describes the details of the results of fabricating a test vehicle with six embedded dies (three-dies in two stacks side-by-side). The fabricated test vehicle had 14 copper layers with less than 0.9 mm thickness. This paper also reports the results of various reliability testing on the package. These results were obtained by electrical measurements of daisy chain patterns formed between some of the layers. The fabricated test vehicle showed high reliability based on the results of a moisture and heat test and heat-shock test. These results show that the WABE technology to embed multiple dies vertically in polyimide film is one of the most promising packaging technologies to significantly miniaturize electronic circuits such as medical electronics.

An Incremental Needle Insertion System (INIS) which simultaneously measures the force and position of a needle during insertion was designed and fabricated for use in a tissue deformation study to improve realism in medical simulation. The INIS was tested in a fresh frozen cadaver experiment and the position of the needle was plotted and compared to the expected needle path. It was found that the INIS is sufficiently accurate with an average path deviation of 1.55 mm. In addition, INIS was shown to successfully measure the maximum Central Venous Catheterization needle insertion force which ranged from 3.02 N to 3.73 N.

Complex, unstable inflow jet has been linked to aneurysm growth and rupture. However, methodologies to characterize this inflow jet have not been well established. Our previous works (Le et al., J. Biomech. Engr., 2010 and Le et al., Annals Biomedical Eng., 2013) have shown a possible transition from the stable mode (cavity) to the unstable mode (vortex ring) of this jet. We have proposed the use of a non-dimensional index called Aneurysm Number to characterize this transition (Le et al., 2013). However, the quantification of such a transition is lacking. Currently, there have no efforts in quantifying unstable flows in intracranial aneurysms, which is essential in stratifying rupture risks. In this work, the aneurysmal geometries from three patients at Sanford Health, North Dakota are reconstructed from Magnetic Resonance Angiogram and Digital Subtraction Angiogram data. Using our in-house CFD code (Virtual Flow Simulator), high-resolution flow data is obtained via numerical simulation. We perform modal analysis of blood flow dynamics for these cases using Proper Orthogonal Decomposition. Our results show that there are up to five dominant modes in the flow arising from the interaction of the incoming jet and the aneurysm dome. The spatial distribution of these modes reflect the characteristics of the inflow jet and can be used to quantify flow unsteadiness. Future works will be needed to apply the same procedure for a larger population of patients to examine its relevance in clinical practice.

Total hip replacement is a widespread medical procedure, with over 300,000 surgeries performed each year in the US alone. The vast majority of total hip replacements utilize press fit fixation, where the implant cup is physically impacted into the patient’s acetabular cavity. Successful seating of the implant requires a delicate balance between inserting the implant deep enough to obtain sufficient primary stability, while avoiding fracture of bone, which causes pain, complications during recovery, and revision surgery. To improve patient outcomes, this surgical field needs assistive technologies that can measure the forces applied during press fit fixation, and provide real-time feedback to guide how much force to apply, and when to stop applying additional forces. The development of such technology, however, requires a greater understanding of the forces experienced at the implant-acetabular cup interface, and the resulting cup insertion and implant stability. Here, we present a preliminary study of acetabular cup insertion into bone proxy samples. We find that as the magnitude of force on the acetabular cup increases, the cup displacement and axial extraction force increase linearly and then plateau. For repeated impacts of a given force, cup insertion and force experienced in bone increase correspondingly and reach a plateaued value over certain number of impacts, which represents rate of insertion. These finding suggest the plausibility of a feedback mechanism that utilizes measured force patterns in bone, implant/bone interface, and impaction tool in relation to rate of insertion to infer optimal primary implant stability in arthroplasty.

Upper airway stimulation (UAS) is shown to be effective with high adherence for patients with moderate to severe obstructive sleep apnea. However, the consistency of adherence among medical sites remains to be verified. This study examines the adherence to UAS among medical sites in an international multicenter registry. A statistically significant adherence decrease between 6-month and 12-month visit was found in the study cohort as well as in most sites. No significant heterogeneity was found among sites with either all patients or only patients who had adherence at both visits recorded. In addition, there is no enough evidence that region and experience of sites influences the adherence. This study indicates that UAS therapy adherence is consistent among sites, regardless of region and experience of sites.

Preterm birth (PTB) is one of the leading causes of neonatal morbidities and mortalities. Limited methods are available to physicians for mitigating PTB, thus posing an urgent need to develop effective methods for its prevention. In prior research, a benchtop electronic uterine control device (EUCD) was developed for tocolysis through injection of current pulses. However, the benchtop version is wall tethered and constrains patients to hospitals, i.e., it is unsuitable for deployment in outpatient or home settings. This paper focuses on the development of a mechatronics-based, low-cost, battery-powered, portable, and reproducible EUCD, which is suitable for use in home and clinical environments. The developed mechatronic version is validated for electrical performance with resistive load-tests, which indicate that the mechatronic device can generate current pulses similar to the existing benchtop EUCD. Furthermore, the signals generated from the device are evaluated for repeatability using coefficient of variation (CV) analysis and the results indicate that the mechatronic version can produce repeatable frequency (1–100Hz), amplitude (1–17mA), and pulse width (1–120ms) modulated current signals. An internet of medical things (IoMT) methodology is discussed to enable seamless transition of the developed device from a clinical environment to a home-based setting for remote use by the patients.

Neurosurgical operations are long and intensive medical procedures, during which the surgeon must constantly have an unobscured view of the brain in order to be able to properly operate, and thus must use a variety of tools to clear obstructions (like blood and fluid) from the operating area. Currently, cotton balls are the most versatile and effective option to accomplish this as they absorb fluids, are soft enough to safely manipulate the brain, act as a barrier between other tools and the brain, and function as a spacer to keep anatomies of the brain open and visible during the operation. While cotton balls allow neurosurgeons to effectively improve visibility of the operating area, they may also be accidentally left in the brain upon completion of the surgery. This can lead to a wide range of post-operative risks including dangerous immune responses, additional medical care or surgical operations, and even death. This project seeks to develop a unique medical device that utilizes ultrasound technology in order to minimize cotton retention after neurosurgical procedures in order to reduce undesired post-operative risks, and maximize visibility.

Recent advancements in wearable medical technologies have streamlined health monitoring with simple, non-invasive measurements. These devices, however, are rarely capable of monitoring all the necessary parameters for an accurate measure of health, such as blood pressure, and can cost the user hundreds to thousands of dollars. The objective of this project was to design an affordable, user-friendly, wearable device capable of monitoring multiple parameters: body temperature, blood pressure, heart rate, blood oxygen, and body positioning. By combining wearable sensors with Inter-Integrated Circuit (I2C) technology, the data from many sensors can be transmitted while maintaining a compact size for a wearable. In parallel with this device, a mobile application was designed as an interface to receive real-time comprehensive measurements. This device could be used to reduce monitor application time in emergency medical settings and monitor patients in rural communities who are often hours away from the nearest medical centers.

Approximately 500,000 dialysis patients in America are at a high risk of hyperkalemia, a condition where blood potassium becomes elevated above normal levels. Hyperkalemia is extremely dangerous, as it can result in severe cardiac complications if untreated. Hyperkalemia may be silent or present vague symptoms until those complications develop, at which point patients require emergency medical care. However, if patients have the ability to measure their potassium levels at home, they could detect hyperkalemia before it reaches a dangerous stage, and seek preventative medical care to avoid severe complications. Therefore, we have designed a novel device allowing patients to measure their blood potassium levels at home. The workflow of our solution is as follows: (1) patients obtain a blood sample from a finger prick, (2) potassium concentration is measured with an ion specific electrode (ISE), and (3) the device displays their potassium levels and a recommended course of action based on their hyperkalemic risk. We validate our solution with three major tests. First, our portable ISE technology must accurately measure potassium concentration in blood samples. Second, appropriate lancet parameters (gauge and depth) to minimize hemolysis in capillary blood samples must be found to minimize falsely elevated readings. Third, device portability and ease of use must be evaluated using patient input, as these factors will affect patient compliance. We have validated the use of portable ISE technology to feasibly measure potassium, and we continue to collect data for our second and third tests.

Extended reality tools have been theorized to revolutionize medicine. Many tools on the market today fail to provide value in a clinical setting. Extended reality tools must emulate existing clinical workflows to add value to a doctor’s process. A framework is created to capture the clinical workflow by defining user tasks, graphical user interface functionalities and backend software functionalities. Two extended reality tool designs are presented based on the workflow captured in the framework. The first extended reality tool is designed for communication and collaboration, while the second tool is designed with a full immersive experience.

With medical institutions increasing the use of medical simulators for educational purposes it is detrimental that the knowledge gap regarding tissue mechanical properties be researched further in depth. The grasper device discussed throughout this paper aims to provide researchers a handheld device capable of testing soft organs and tissue in-vivo and ex-situ in a laboratory setting. The device consists of two load cells on the inner jaws of the grasper to measure compressive force and an encoder to monitor the graspers angular position which yields tissue position and strain. Accompanying the grasper is a GUI written in Rust which is capable of data file management, and providing a 10 second live feed of load cell and encoder readings. The grasper device is currently being employed in a study testing the tissue mechanical response of porcine tissue at states ranging from in-vivo to ex-situ post freeze. The results from this test, and subsequent tests using the grasper have the capability of providing much needed knowledge regarding tissue mechanical properties to improve medical simulators and medical education as a whole.

Robot assisted surgery has been widely accepted by the medical community. Surgeons utilize robots in many different procedures worldwide. However, cardiothoracic surgeons do not regularly use robotic tools to aid them in performing even simple, catheter based procedures such as cardiac ablation or mapping. Some cardiac Monophasic Action Potentials (MAPs) and ablation catheters require a specific window of force to either effectively characterize or scar cardiac tissue. This is challenging to maintain through the cardiac cycle, so the application of a constant force is not a trivial task for surgeons. Robotic assistance to control the force applied to a catheter through ablation and mapping procedures is needed to improve the outcome for patients. The purpose of this work is to develop a single degree of freedom robot that controls the force applied to a beating swine heart. Rather than trying to predict the motion and timing of the heartbeat, or tracking its movement this robot senses and reacts to the force produced by the myocardium. Through the cardiac cycle, the robot applies a constant force to the surface of a beating heart. The kinematics of the cardiac tissue were characterized by utilizing piezoelectric transducers. Hardware to control the catheter motion was designed to fit most commercially available devices. The controller was designed by first building a mathematical model using measured data, and then a control law was implemented considering the heartbeat as disturbances to the system. Finally, testing was completed with dry runs, and in situ and ex-vivo testing in the Visible Heart ® Laboratory.

Fine and gross motor skills of the hand are essential to complete the work of surgery. During examinations and surgery, the hand becomes a surgeon and a medical professional’s first point of contact with a patient, as they use their hands to perform tasks with various tools while wearing gloves. The anthropometry of hands and the interaction of the tool can affect the probability of developing a musculoskeletal injury [3]. Tools for healthcare professionals are typically designed using male anthropometric data taken from only one position using tape measures and calipers. The problem with this approach is that humans are rarely in these positions when carrying out everyday tasks and hand measurements and form change with movement. This paper discusses a new method of capturing dynamic hand anthropometry through the use of 3D scanners, to address traditional anthropometric hand data’s limitation. Based on an initial assessment of surgical instruments, six functional hand grasps were selected and compared to traditional hand anthropometric poses. Using these poses, a pilot study with one male was conducted. In total 65 measurements were gathered through 8 poses. The positions with the largest range of measurement change were: Total Hand Length-Palmar with 48 mm, Total Hand Length-Dorsal with 39 mm, and the tip of the first digit through webspace to the tip of digit 2 (Web) with 26 mm. Understanding dimensional change in select areas of the hand is essential to developing more ergonomic, better fitting products for surgeons and medical professionals. A 26–48 mm dimensional change can have a significant impact on the positioning of surgical tool properties, as well as the functionality of the tool and precision of work for surgeons and medical professionals with different hand sizes. This pilot study demonstrated the feasibility of using functional hand grasps as a basis for collecting hand anthropometric data using a 3D scanner.

This paper discusses the design and application of magnetic-based position tracking in surgical trainers. The utilization of magnetic-based position tracking in Laparoscopic Trainers provides a cost-effective solution to the next generation of medical education, training and evaluation. The utilization of 3D printed parts as well as off the shelf electronics allows us to maximize accuracy while minimizing design cost. Our current design costs less than $300.00 while providing results with an error of 1.474–14.265%.

Preterm and critically ill infants are treated in neonatal intensive care units (NICUs), where human milk is increasingly recommended and prescribed to this population as a medical intervention [1]. However, due to the medical acuity and complex character of caring for preterm infants, sometimes feeding at the breast is not possible. When feeding at the breast is not possible medical devices or commercial products may influence a mothers’ decision to express human milk for her NICU infant. Feeding human milk to infants cared for in NICUs reduces rates of mortality by decreasing instances of necrotizing enterocolitis (NEC) especially for extremely low birthweight infants [2] and is implicated in reducing incidence and severity of retinopathy of prematurity [3].

The ability to investigate sleep is of scientific and clinical interest. Polysomnography (PSG) has long been considered the gold standard assessment for sleep physiology; however, its cost and inconvenience have spurred the development of consumer devices capable of evaluating sleep outside the laboratory. The development of dedicated consumer sleep monitoring devices, e.g., the Zeo Personal Sleep Manager, smart bands, e.g., the Microsoft Band 2 (MB2), and activity trackers, e.g., the Fitbit Charge 2 (FC2), with the ability to automatically distinguish between sleep and wakefulness has important implications for sleep research and medicine. 1–3

Intra-abdominal organ and vascular injuries during laparoscopic trocar placement remain a significant cause for surgical complications during laparoscopic procedures. These complications can arise if the surgeon deviates from the proper placement axis, requiring additional applied force to obliquely traverse the abdominal wall. This increase in force application increases the risk of internal vessel and organ damage immediately after entrance to the peritoneal cavity. To mitigate this risk, our group designed a trocar that provides real-time feedback of deviation from the proper insertion axis, applied force, and position of the trocar tip within the tissue. This was performed using an accelerometer, load cell, and electrical impedance measurement. Our device was tested in a surgical simulation laboratory by medical students using a porcine abdominal wall model. Results establish our device as an effective training tool for educating surgeons on trocar placement in laparoscopic surgery.

The increasing complexity of the medical regulatory environment and the inherent complexity of medical devices, especially due to the increased use of connected devices and embedded control software, impose adoption of new methods and tools for the system design, safety and security analyses. In this paper, we propose a method and an associated toolchain to couple model-based system engineering and safety/security analyses at the design phase of medical devices. The method is compliant with ANSI/AAMI/ISO TIR57 safety and security guidance, and compatible with INCOSE Biomedical-Healthcare Model-Based Systems Engineering works. The toolchain is based on a system architecture modelling tool and supports medical device domain specific reference architecture, as well as tools for safety and security risk analyses. The proposed method and toolchain are illustrated by considering a RGB’s TOF-CUFF monitor device analyzed in the scope of the AQUAS project as a medical device use case.

In this study, a commercially available computational fluid dynamics (CFD) program was used to simulate coil embolization techniques, standard coiling (SC) and stent-assisted coiling (SAC), in simplified vessels that are representative of vessels found in the brain. The test models included a curved vessel, ranging from 3mm to 4mm in diameter. The vessel was afflicted with a spherical aneurysm, ranging from 8mm to 16mm in diameter. The four test cases were simulated without treatment, with SC treatment, and with SAC treatment, for a total of twelve simulations. The parameters of interest were blood volume flow into aneurysm, fluid velocity, wall shear stress (WSS), and vorticity. Results of the simulations indicate, on average, SC and SAC reduced volume flow into the aneurysm by 50% and to over 60%, respectively. Both SC and SAC appeared to reduce distal neck WSS. Both treatments reduced average overall dome WSS by approximately 76%. Average aneurysm neck velocity was reduced by both treatments; SC reduced neck velocity by 69% and SAC reduced neck velocity by 75%. Information on SC and SAC efficacy in idealized scenarios could assist medical professionals determining viable approaches for patient-specific cases and lays foundation for future CFD studies exploring coil embolization treatments.

According to the CDC, 795,000 Americans are diagnosed with a stroke each year. Out of the all of the technology used to track the gait of a stroke patient, the Inertial Measurement Unit (IMU) is growing in recognition and use. These are often used as wearable sensors for rehabilitation, with their small size and cost effectiveness. The purpose of this research is to detail the innovation of an android application with the ability to receive IMU data and present it through medically significant visual displays. The data from a device is received via bluetooth, and is transmitted in terms of angles roll (x axis), pitch (y axis) and yaw (z axis). The application displays this data to allow the user to track the position of the IMU in live time. The medical professional has the ability to input a desired set of angles, and track the proximity of a connected device to the target position. The data is presented visually through the coronal, transverse & sagittal plane. When roll and pitch angles from the app were compared to angular values measured on a protractor, the average difference was +/− 0.366° and +/− 0.436°, in roll and pitch respectively. Along with the average accuracy being less than a 0.5° difference, the application has the ability to connect and track 3 IMU devices simultaneously. The data can be stored and exported. The greatest limitation is angular presentation latency. This creation has the potential to catalyze creation of an app that can track a high number of devices simultaneously, with high accuracy and low signal latency. The ability to track and position wearable IMU sensors using a smartphone or tablet offers an exciting future in rehabilitation, especially for recovering stroke patients.