Miniature Pump for Treatment of Refractory Ascites Based on Local Magnetic Actuation
This paper presents the design, fabrication, and experimental validation of a novel low-cost implantable pump for the treatment of refractory ascites (RA) based on local magnetic actuation (LMA). A reciprocating positive displacement pump displaces liquid unidirectionally through magnetic coupling with a magnetic controller placed on the outside of the patient's body. The proposed solution is intuitive to use given an alignment algorithm that exploits externally placed magnetic field sensors (MFS). The implantable device has a catheter-like shape, is electronic free (no on-board battery), has low fabrication cost (<8 â€...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Design and Analysis of a Novel Lightweight, Energy Economic Powered Knee Orthotic Device
This study proposes a novel design of PKOD, where we have focused on the betterment of the mentioned features with the help of a new mechanism, namely a four-bar controlled compliance actuator (FCCA). In FCCA, instead of using the widely used screw transmission mechanism, a four-bar mechanism is used to modify the joint's angular deviation and stiffness. The main advantages of using FCCA over other existing mechanisms are to reduce the power consumption by amplification of input motor torque and to achieve a faster response at the same time, and these are achieved by utilizing a simple four-bar mechanism. In the proposed d...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

A Parallel Multiple Layer Cryolithography Device for the Manufacture of Biological Material for Tissue Engineering
While three-dimensional (3D) printing of biological matter is of increasing interest, current linear 3D printing processes lack the efficiency at scale required to mass manufacture products made of biological matter. This paper introduces a device for a newly developed parallel additive manufacturing technology for production of 3D objects, which addresses the need for faster, industrial scale additive manufacturing methods. The technology uses multilayer cryolithography (MLCL) to make biological products faster and in larger quantities by simultaneously printing two-dimensional (2D) layers in parallel and assembling the l...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

An Extensible Orthopedic Wire Navigation Simulation Platform
The demand for simulation-based skills training in orthopedics is steadily growing. Wire navigation, or the ability to use 2D images to place an implant through a specified path in bone, is an area of training that has been difficult to simulate given its reliance on radiation-based fluoroscopy. Our group previously presented on the development of a wire navigation simulator for a hip fracture module. In this paper, we present a new methodology for extending the simulator to other surgical applications of wire navigation. As an example, this paper focuses on the development of an iliosacral wire navigation simulator. We de...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

An Investigation Into the Challenges of Using Metal Additive Manufacturing for the Production of Patient-Specific Aneurysm Clips
Cerebral aneurysm clips are biomedical implants applied by neurosurgeons to re-approximate arterial vessel walls and prevent catastrophic aneurysmal hemorrhages in patients. Current methods of aneurysm clip production are labor intensive and time-consuming, leading to high costs per implant and limited variability in clip morphology. Metal additive manufacturing is investigated as an alternative to traditional manufacturing methods that may enable production of patient-specific aneurysm clips to account for variations in individual vascular anatomy and possibly reduce surgical complication risks. Relevant challenges to met...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Process –Structure–Property Relationships in Selective Laser Melting of Porosity Graded Gyroids
Selective laser melting (SLM) can be used to tailor both the geometry and mechanical properties of lattice structures to match bone properties. In this work, a process –structure–property (PSP) relationship for Ti6AL4V porosity graded gyroids (PGGs) structures was developed. A design of experiment approach was used to test the significance and contribution of different process parameters on microstructure, morphology, and mechanical properties. Process maps to predict the morphology errors at specific laser power and scan speed were developed. Moreover, the mechanical properties of radially PGGs with a relative density...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Custom Patient-Specific Three-Dimensional Printed Mitral Valve Models for Pre-Operative Patient Education Enhance Patient Satisfaction and Understanding
In recent years, advances in medical imaging and three-dimensional (3D) additive manufacturing techniques have increased the use of 3D-printed anatomical models for surgical planning, device design and testing, customization of prostheses, and medical education. Using 3D-printing technology, we generated patient-specific models of mitral valves from their pre-operative cardiac imaging data and utilized these custom models to educate patients about their anatomy, disease, and treatment. Clinical 3D transthoracic and transesophageal echocardiography images were acquired from patients referred for mitral valve repair surgery ...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

The Evaluation of a Novel Three-Dimensional Printed Expandable Pedicle Screw Sleeve Insert
When used in combination with decompression, spinal fusion is a successful procedure for treating patients with spinal stenosis and degenerative spondylolisthesis. While a number of auxiliary devices have been proposed to enhance the fixation of the screw within the pedicle and vertebral body, there is conflicting information regarding the efficacy of their use. Therefore, the aim of this study was to determine the ability of a novel expandable pedicle screw to improve the fixation of the pedicle screw within the pedicle and vertebral body. A three-dimensional (3D) printed, screw sleeve was designed that expanded within th...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Novel Design of a Three-Dimensional Printed Umbilical Cord Clamp: A Proof of Concept Study
Parents frequently report complaints regarding the excessive size of the clamp that create concerns of hooking to the clothes and inducing premature separation of the dried cord. We aimed to design three-dimensional (3D) print and test a novel umbilical clamp which would be smaller, more ergonomic, and would look more appealing to the parents. After the design and 3D printing process, the clamps were tested for fluid leak on fresh umbilical cord specimens. The umbilical vein was cannulated with a 4F feeding tube which was attached to the saline infusion bag inserted in a pressure infusion cuff. The compressed cord width wa...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Are Medical Grade Bioabsorbable Polymers a Viable Material for Fused Filament Fabrication?
This study demonstrated the feasibility of utilizing medical grade bioabsorbable polymers in FFF. (Source: Journal of Medical Devices, Transactions of the ASME)
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Fingertip-Sized Pressure Sensor for Luer Taper of Three-Way Stopcock in Liquid Channel
We developed an easily attachable fingertip-sized pressure sensor (FSPS) for a three-way stopcock in a liquid channel of a heart –lung machine. The FSPS has a double-pipe structure with a semispherical soft film cap on the pointed end and a diaphragm semiconductor strain sensor on the other end. An enclosed space of variable volume covered with the soft film cap prevents the semiconductor strain sensor from coming into dire ct contact with blood, and the double-pipe structure decreases the strain on the strain sensor when inserting the FSPS into the female-fitting part of the luer taper. It is difficult to fabricate a ve...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Self-Contained Three-Dimensional Bioprinter for Applications in Cardiovascular Research
Bioprinting is a technique of creating 3D cell-laden structures by accurately dispensing biomaterial to form complex synthetic tissue. The printed constructs aim to mimic the native tissue by preserving the cell functionality and viability within the printed structure. The 3D bioprinting system presented in this paper aims to facilitate the process of 3D bioprinting through its ability to control the environmental parameters within an enclosed printing chamber. This design of the bioprinter targets to eliminate the need for a laminar flow hood, by regulating the necessary environmental conditions important for cell surviva...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

The Sparthan Three-Dimensional Printed Exo-Glove: A Preliminary Evaluation of Performance Via Case Study
This paper describes the development and testing of a low-cost three-dimensional (3D) printed wearable hand exoskeleton to assist people with limited finger mobility and grip strength. The function of the presented orthosis is to support and enable light intensity activities of daily living and improve the ability to grasp and hold objects. The Sparthan Exoskeleton prototype utilizes a cable-driven design applied to individual digits with motors. The initial prototype is presented in this paper along with a preliminary evaluation of durability and performance efficacy. (Source: Journal of Medical Devices, Transactions of the ASME)
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Methodology for Hemodynamic Assessment of a Three-Dimensional Printed Patient-Specific Vascular Test Device
Assessing hemodynamics in vasculature is important for the development of cardiovascular diagnostic parameters and evaluation of medical devices. Benchtop experiments are a safe and comprehensive preclinical method for testing new diagnostic endpoints and devices within a controlled environment. Recent advances in three-dimensional (3D) printing have enhanced benchtop tests by allowing generation of patient-specific and pathophysiologic conditions. We used 3D printing, coupled with image processing and computer-aided design (CAD), to develop a patient-specific vascular test device from clinical data. The proximal pulmonary...
Source: Journal of Medical Devices, Transactions of the ASME - July 15, 2019 Category: Medical Devices Source Type: research

Pulse Oximeter for Low SpO 2 Level Detection Using Discrete Time Signal Processing Algorithm
Oximeter is an important clinical device used for measuring peripheral capillary oxygen saturation (SpO2) in blood and hence accurate results are needed in order to help physicians predict clinical problems in the initial stage(s) of liver or kidney diagnosis. Different issues associated with the accuracy of SpO2 and heart rate measurement accuracy are studied in this work. With the understanding of these issues, a new SpO2 monitoring system is proposed that comprises of a better detection method, novel discrete time signal processing (DTSP) algorithm, and a custom-made oximeter probe head. The proposed SpO2 measurement sy...
Source: Journal of Medical Devices, Transactions of the ASME - May 2, 2019 Category: Medical Devices Source Type: research