bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Design of the Miniature Force Sensor Based on Strain Gages for Ablation Catheter
Authors: Shi Xiaochan , Gu Xuelian , Tan Jiahong , Liang Bo 
Published: October 2017

Recently, the radiofrequency ablation catheter is widely used in the treatment of atrial fibrillation. Radiofrequency catheter tip is inserted through femoral vein puncture and pushed to the heart cavity. The radio frequency energy is applied to the ablation lesion on the inner wall of the heart, and then the heart cells die to achieve the aim of treatment[1]. During the treatment, however, the patients need repeated ablation because of the ineffective ablation, and the complications may occur. Continuous pulmonary vein lesion and isolation of wall is very important to increase the success of surgery [2]. Research [3] shows that the contact force between catheter tip and the tissue of inner heart is a key factor influencing the lesion size.
In order to monitor the contact force, many force sensors have been studied. Fukuda [4] used semiconductor strain gage outside of the catheter to monitor the contact force. Peirs [5] monitored the contact force by optical technology.
The disadvantages of the current sensors are using special expensive signal detecting and analyzing instrument, such as Endosense (SMART touch), which will increase the cost tremendously. For clinical application, it is necessary to develop a low cost sensor with enough accuracy which can also be used in the catheter for contact force measurement.
This paper focuses on designing a novel force-voltage transferring sensor. The sensor consists of a Ni-Ti alloy tube and several strain gages. With the compact design of a spiral structure, it can reduce the overall cost while keeping a good performance at the same time. The price of SMART touch catheter is 4, 348 dollars. The proposed design will be as much as 20–30 percent below SMART’s price.
Time Variate Comparison of In Situ and In Vitro Monophasic Action Potential Recordings
Authors: Schmidt Megan M. , Iaizzo Paul A. 
Published: October 2017

Monophasic action potentials (MAPs) have long been used as a means to study the focal electrical activity of the myocardium. [1, 2] Upon the application of adequate contact force, the signals provide important insights into focal depolarization and repolarization, activation timing, and focal arrhythmic behaviors. [3–6]
Within our laboratory we have developed an isolated physiologic, four-chamber working, large mammalian heart model (the Visible Heart® methodology) to study cardiac devices and their interactions with the myocardium. [7] Through the use of a modified Krebs-Henseleit buffer, we can uniquely visualize the device-tissue interface: in this study, the placement of catheters.
The purpose of this study was two-fold. First, we demonstrated the long term stability of MAP recordings in an in situ swine model. Second, we showed the relationship between MAPs recorded from in vitro and in situ preparations of each specimen.
Development of a Robotic Motor Skills Assessment System for Children With Autism
Authors: Subramani Guru , Fisher Aubrey M. , Bittmann Moria F. , Mason Andrea H. , Travers Brittany G. , Zinn Michael R. 
Published: October 2017

Autism is a developmental disorder characterized by atypical social interactions and repetitive behaviors/restricted interests[1]. It is found that children with autism also experience delayed or impaired motor skills development [2]. It would be advantageous to develop methods that precisely evaluate these motor skills impairments. The use of robots for evaluating upper limb motor competency have been looked at in the stroke literature [3]. We would like to leverage robotic tools for motor skills assessment but with focus for children with autism spectrum disorder.
Robotic methodologies provide a unique way of testing upper limb motor skills. For instance, if a person holds on to the end of a robot arm and moves the robot arm in space, the robot can apply forces and prevent or assist the person with these motions. In this fashion, the robot can apply perturbations in a repeatable and precise manner with high fidelity.
Since individuals with autism have anxieties interacting with other individuals[4], using an impersonal robot would alleviate the anxiety of social interactions. These individuals learn motor skills best with consistent repetition and strong reinforcement, qualities that robots provide.
Therefore, a robot based evaluation strategy and therapy paradigm for children with Autism would be beneficial for the community.
A Novel Hyperspectral Endoscopic Imaging Method Based on Broad- and Overlapped-Band Filters
Authors: Han Zhimin , Xie Tianyu , Zhang Aoyu 
Published: October 2017

In medical domain, hyperspectral imaging (HSI) [1] offers a hybrid modality of optical diagnostics that obtains spectral information and renders the information in image form, thus it has great potential for noninvasive disease diagnosis and surgical guidance [2]. Masood [3] explored a series of research problems for classification of hyperspectral (HS) colon biopsy images, and concluded that HSI has enough discriminatory power to distinguish normal and malignant biopsy tissues.
However, HS illumination is always with low intensity and signal-to-noise (SNR) ratio is low for HS images. The reason is that sensors of endoscopic systems, such as charged-couple-device (CCD), work by converting photons into electrons which are then stored in each pixel. The number of electrons stored in each pixel well is proportional to the number of photons that struck that pixel, although in actual pixel well, electrons are not only generated when receiving photons, but also due to physical processes within CCD itself, such as thermal noise which generates additional electrons dependent to temperature [4,5]. At the same time, dispersive device such as monochromators (such as prism and grating), and optical filters (including interference filters and tunable filters) are commonly used for HS imaging. Using these traditional filtering approaches, only a low fractions of photons are transmitted into the sensor. Moreover, due to the requirements of safety and keeping the working time per frame as short as possible for in-vivo and real-time application in medical domain, common methods which could improve SNR, such as using cooled sensor or high exposure time, are not applicable for HS endoscopy systems. To overcome this drawback, we proposed this novel HS imaging method based on broad- and overlapped-band filters [6].
Toward Inkjet Additive Manufacturing Directly Onto Human Anatomy
Authors: Johnson Reed A. , O’Neill John J. , Dockter Rodney L. , Kowalewski Timothy M. 
Published: October 2017

Bioprinting technology has been rapidly increasing in popularity in the field of tissue engineering. Potential applications include tissue or organ regeneration, creation of biometric multi-layered skin tissue, and burn wound treatment [1].
Recent work has shown that living cells can be successfully applied using inkjet heads without damaging the cells [2]. Electrostatically driven inkjet systems have the benefit of not generating significant heat and therefore do not damage the cell structure. Inkjets have the additional benefit of depositing small droplets with micrometer resolution and therefore can be used to build up tissue like structures.
Previous attempts at tracking and drawing on a hand include either direct contact with the hand [3] or tracking the hand only in two degrees of freedom [4]. In this work we present an approach to track a hand with three degrees of freedom and accurately apply a substance contact free to the hand in a desired pattern using a bioprinting compatible inkjet. The third degree of freedom, in this case depth from the hand surface, provides improved control over the distance between the inkjet head and object, thus increasing deposition accuracy.
A Novel Epidural Catheter Fixation Device
Authors: Cavanagh Daniel P. , Abay Asena , Brito Jessica M. , Joyner Jasmine R. , Nally Jordyn N. , Wu Xianren 
Published: October 2017

Epidurals are a method of long-term pain relief administered by injecting and continuously delivering an anesthetic via catheter in the spine. This method of pain relief is often used for patients in the Obstetrics/Gynecology unit as well as those in pre- and post-operational care. For almost 2 million singleton vaginal deliveries across 27 states in 2008 (representing 65% of all US singleton vaginal births in 2008), 61% of patients received some form of an epidural or spinal injection [1]. Additionally, this number has been increasing. For the 18 states for which 2006 and 2008 data are available, the average of the state-level increases in epidural/spinal injections is approximately 4.2% revealing an overall increase in these injections. Just between 2000 and 2010, the use of epidural injections increased by 160% [2]. Commonly, epidural catheters are inserted into the patient’s back in the appropriate location and then secured to the body with an adhesive medical dressing.
Movement and subsequent dislocation of the catheter beneath the adhesive medical dressing can result in inefficient anesthetic delivery, increased patient discomfort, and repeated administration of the epidural. Secondary migration of epidural catheters is a problem responsible for failure in approximately 6.8% of epidurals administered [3]. Requiring an anesthesiologist to repeat the procedure is also an increased cost. A solution to secondary migration of epidural catheters would ensure effective delivery of the anesthetic to the patient, reduce the need for a repeated procedure, and prevent unwanted additional healthcare expenses.
Interpreting Ultrasound Images for Accurate Epidural Needle Insertion
Authors: Vaughan Neil , Dubey Venketesh N. 
Published: October 2017

This work presents development and testing of image processing algorithms for the automatic detection of landmarks within ultrasound images.
The aim was to automate ultrasound analysis, for use during the process of epidural needle insertion. For epidural insertion, ultrasound is increasingly used to guide the needle into the epidural space. Ultrasound can improve the safety of epidural and was recommended by the 2008 NICE guidelines (National Institute for Health and Care Excellence). Without using ultrasound, there is no way for the anaesthetist to observe the location of the needle within the ligaments requiring the use of their personal judgment which may lead to injury. If the needle stops short of the epidural space, the anaesthetic is ineffective. If the needle proceeds too deep, it can cause injuries ranging from headache, to permanent nerve damage or death.
Ultrasound of the spine is particularly difficult, because the complex bony structures surrounding the spine limit the ultrasound beam acoustic windows [1]. Additionally, the important structures for epidural that need to be observed are located deeper than other conventional procedures such as peripheral nerve block. This is why a low frequency, curved probe (2–5 MHz) is used, which penetrates deeper but decreases in resolution.
The benefits of automating ultrasound are to enable real-time ultrasound analysis on the live video, mitigate human error, and ensure repeatability by avoiding variation in perception by different users.
Previous ultrasound image processing for epidural research used speckle image enhancement with canny and gradient based methods for bone detection [2]. A clinical trial with 39 patients had success detecting the ligamentum flavum (LF) from ultrasound by algorithms in 87% of patients.
Echogenic needles and catheters are now becoming available which are enhanced for extra ultrasound visibility. The Epimed UltraKath ULTRA-KATH™ [3] has a patented design to maximize visibility under ultrasound [4]. The Echogenic Tuohy Needle also includes imprints on the needle tip that reflects ultrasound, allowing for better visualization. Curved needles can also be detected in 2D ultrasound images [5].
Validation of an Instrumented Wheelchair Hand Rim
Authors: Gaglio Alan , Daigle Scott , Gacek Elizabeth , Jahanian Omid , Slavens Brooke , Rice Ian , Hsiao-Wecksler Elizabeth 
Published: October 2017

An estimated 3.26 million manual wheelchair users (MWUs) exist in the United States [1]. MWUs report a high incidence of upper extremity joint pain largely attributed to wheelchair propulsion, which exposes the upper limbs to high forces and torques repetitively over time [2]. There exists a clear need for assistive wheelchair technologies capable of reducing the loads experienced by the upper extremity joints during propulsion.
IntelliWheels, Inc. has developed multi-geared wheel systems, including both low and high gear systems, where a planetary gear train connects the wheel hub to the wheel hand rim. Decreasing gear ratio, we hypothesize, may reduce the forces and torques required by the user during propulsion. To evaluate this claim, we constructed and validated an instrumented wheelchair hand rim system capable of use on either geared or standard wheelchair wheels. Commercially available devices exist to perform wheelchair kinetics, such as the SmartWheel (SW) (Three River Holdings LLC; Mesa, AZ, USA), however, these devices require the use of a manufacturer specified wheel. As a result, a custom solution was required to interface with the geared wheels used in this study.
A Motorized Robotic Walker for Human Walking Assistance
Authors: Afsar Md Rayhan , Wadsworth Michael , Shen Tao , Zhang He , Ye Cang , Shen Xiangrong 
Published: October 2017

Impaired mobility is ranked as one of the most important factors that have both physical and mental impacts on patients’ life [1]. The impacts are especially serious for the rapidly expanding elderly population in the United States, which is expected to reach 71 million, approximately 20% of the total population, by 2030 [2]. Existing assistive tools, such as cane and walker/rollator, are helpful for such mobility-challenged individuals by providing additional support in walking. However, such tools also disrupt the users’ walking rhythm and increase their metabolic energy consumption. Wheelchairs, especially powered wheelchairs, are also used extensively among this population. Although wheelchairs are effective in transporting patients, they largely preclude the users’ lower limb muscle activities and bone load-carrying, and accelerate the musculoskeletal degeneration of the user’s lower limb [3].
To address the issues with existing assistive tools, the authors developed a new motorized robotic walker for mobility-challenged users. With the objective of assisting the users’ ambulation in a safe and convenient way, the robotic walker features two independently controlled wheels for the maneuverability of the robot, and two parallel bars for the user support in walking. Unlike similar robotic walkers in prior works (e.g. [4]), no wearable sensors are required for the user. Instead, a 3D computer vision system is used to measure the relative position of the user versus the robot, and the control commands are generated accordingly. The details of the robot design and control are presented in subsequent section.
Fabrication and Testing of Breast Tissue-Mimicking Phantom for Needle Biopsy Cutting: A Pilot Study
Authors: Jheng Yu-Chen , Lin Chi-Lun 
Published: October 2017

Breast lesion tissue can be extremely stiff, e.g. calcification or soft, e.g. adipose. When performing needle biopsy, too small or scanty samples can be retrieved due to the tissue is mainly compressed instead of being cut. In order to studying the tissue cutting performance in various cutting conditions, tissue-mimicking phantoms are frequently used as a surrogate of human tissue. The advantage of using tissue phantoms is that their mechanical properties can be controlled. The stiffness of a tissue phantom can be measured by an indentation test. Previous studies have demonstrated mathematic models to estimate Young’s moduli of tissue phantoms from force-displacement data with an adjustable coefficient according to the geometry of the indenter.
Tissue force reactions occurred needle insertion has been largely researched [1], but few studies investigated the tissue cutting with a rotational needle, which is a cutting method largely used in the breast needle biopsy. Research has demonstrated that the influence of rotation can significantly reduce the insertion force [2], but the experiment was conducted on a specific formula of silicone-based tissue phantoms.
This paper served as a pilot study of a large-scale experiment to study the effect of rotational cutting on various cutting conditions and target materials, including artificial and biological soft tissues. Two most common types of soft tissue phantoms, biopolymers (gelatin gels and agar) and chemically synthesized polymers (polydimethylsiloxane, PDMS) were investigated. Indentation tests were performed to estimate the mechanical properties of tissue phantoms which were then verified by finite element simulations. Tissue cutting tests with and without rotation were conducted to evaluate the effect of needle rotation on the tissue force reactions.
Design of a Novel Radio Frequency Ablation Probe for Tumor Ablation Treatment
Authors: Den Adel Colleen , Husler Zena-Maria , Han Yen-Lin 
Published: October 2017

Hepatocellular carcinoma (HCC), commonly known as the liver cancer, is a severe health concern worldwide. For patients with liver tumors that are difficult to remove through traditional treatments such as radiation, chemotherapy and partial hepatectomy, there is the option of radiofrequency ablation (RFA) treatment. RFA is a minimally invasive procedure that is currently treating liver tumors that are relatively small in size. Radiofrequency ablation uses currents to heat up the tissue of the tumor. Once the temperature of the tissue reaches approximately 60° C tissue necrosis begins to occur [1]. With current RFA probes, ablation lesions are typically 3–5.5 cm in diameter [2]. It is important that all of the tumor tissue is ablated, so it is necessary to also kill a small amount of the surrounding healthy tissue. At least 1 cm of healthy tissue should be ablated to ensure the tumor will not recur [2]. Hence, many studies [3, 4] have attempted to increase the RFA ablation zone through various methods including adding saline to the tissue, predicting the optimal power level, etc.
To focus on safely increasing the size of the ablation zone and to improve upon the spherical geometry of the tumors, the “Christmas tree” and “umbrella” style probes [5], which utilize multi-pronged electrodes (tines), are currently available in the market. The electrodes, or wires of the probe, are responsible for producing heat and making contact with the liver tissue at all time in order to execute the tissue ablation. For the umbrella and Christmas tree style probes, the drawbacks include: 1. the gauge of the tines limit the ablation scope of the probes; 2. their ability to achieve higher volumes of cell death are limited due to their static geometry, which has fixed diameters; 3. towards the outer edge of the tumor, due to their static geometry and the loss of contact with live tissues, the rate of killing cancerous cells decreases drastically due to the decrease in heat transfer rate, which is a result of the lack of heat sink from perfusion in the live tissues [6].
It was noticed that an improvement could be made to the efficiency of these multi-pronged electrodes if they were free to expand as the area of tissue was ablated. Therefore, a novel dynamic RFA probe was proposed by Lau and Han and numerical simulations using COMSOL Multiphysics Joule heating module have concluded that this dynamic RFA probe can achieve a higher ablation volume with a shorter procedure time [7]. The main goal of this study is to realize the design of this dynamic RFA probe with expandable electrodes to create the largest and most replicable ablation zone. In this study, the deployment mechanism and the proposed design of the dynamic probe are discussed and the analytical solutions of the electrode expansion profiles are presented. The ablation zones are estimated analytically based on the dynamic expansion of the electrodes.
Kinetic Measurement Platform for Open Surgical Skill Assessment
Authors: Wijayarathne Lasitha , Hammond Frank L. 
Published: October 2017

Current surgical skill assessment methods are often based on the kinematics of manual surgical instruments during tool-tissue interactions. Though kinematic data are generally regarded as a sufficient basis for skill assessment, the inclusion of kinetic information would allow the assessment of measures such as “respect for tissue” and force control, which are also important aspects of surgical proficiency. Kinetic data would also provide a richer data set upon which automated surgical motion segmentation and classification algorithms can be developed. However, the kinetics of tool-tissue interactions are seldom included in assessments, due largely to the difficulty of mounting small sensors — typically silicon strain gauges — onto surgical instruments to capture force data. Electromagnetic (EM) or optical trackers used for kinematic measurement are often tethered, and thus having tethered force sensors also mounted on the same surgical instruments would complicate the experimental process and could affect/distort the acquired data by impeding the natural manual motions of surgeons.
We present a surgical skill assessment platform which places the kinetic sensors in the environment, not on the instruments, to reduce the physical encumbrance of the system to the surgeon. This system can capture kinetic data using a standalone force/torque sensor embedded in a custom designed workspace platform, and kinematic data using EM trackers placed on the instruments. This portable platform enables the empirical characterization of open surgery motion trajectories and corresponding kinetic data without need for a centralized acquisition site, and will eventually be integrated into a completely untethered skill assessment system.
Development and Testing of an External Fixation Coupling for a Damage Control Orthopedic System
Authors: Ruhala Laura , Beck Dennis , Ruhala Richard , Megal Aaron , Perry Megan 
Published: October 2017

Seligson [1] describes how Hoffmann and Jaquet, a medical doctor and an engineer, respectively, developed the original Hoffmann fixator as a tool to stabilize human fractures with minimal invasiveness.
Whether being utilized in mass trauma injury situations such as the 2010 Haitian earthquake, within our emerging geriatric population, or in veterinary applications, external fixation is widely used [1–4]. In this investigation, a rod-to-wire coupling, shown in Figure 1, and hereafter referred to as the R2W clamp, has been designed and validation tested for Stryker Orthopaedic’s Hoffmann II (HII) External Fixation System. As the name implies, this clamp has the purpose of connecting 8mm rods to 1.5mm or 2mm Kirschner (k-) wires or olive wires to stabilize bony fragments in the lower extremity, thus expediting healing in a trauma case. This paper summarizes the results of the validation tests conducted on prototype clamps.
This clamp effectively allows placement of a wire to further stabilize a frame [3] by allowing wire placement without the addition of an intermediate ring, as shown in Figure 2. The wire could be added to any configuration with two parallel rods extending in plane with the bone.
As shown in Figure 3, the R2W clamp can be positioned “outboard” with the rod between it and the bone, or “inboard” between the rod and the bone, allowing the surgeon geometric flexibility. The use of two k-wires is recommended to stabilize each bone fragment [5].
One of the goals of the validation testing was to determine the effectiveness and functional safety of the clamp as related to surgically applied k-wire tensions of either 50 kg or 100 kg.
Since it is feasible that surgeons may tighten, loosen, then retighten the clamp while positioning it during surgery, the effects of clamp retightenings on the performance of the R2W clamp were also evaluated [4].