Three-dimensional printed flow phantom model of the carotid artery in preterm infants for training and research

The aim of this study was to perform flow volume measurements with Doppler ultrasound using novel 3D printed flow phantom models of carotid artery in preterm infants with varying characteristics. Clinical data from cerebral blood flow measurements using Doppler ultrasound of the right common carotid artery from premature newborn infants were used to produce a 3D printed Doppler flow phantom model with three different vessel diameters; 0.158 cm, 0.196 cm and 0.244 cm. Leading edge to centre was used to measure vessel diameter. Two observers performed flow volume measurements using continuous and pulsatile flow. Agreement between observers was examined using Bland-Altman plots. 24 measurements were performed. 18 (75%) measurements were performed using continuous flow. Pulsatile flow measurements were performed on lumen diameter of 0.244 cm only using physiological rates. Bland-Altman analysis for continuous flow measurements for observer 1 and 2 were -0.007 (95%LOA -4.3 to 4.3) ml/min and 3.2 (95%LOA -2.7 to 9.1) ml/min. Bias for pulsatile flow measurements for observer 1 and 2 were 1.5 (95%LOA -0.8 to 3.8) ml/min and 4.6 (0.7 to 8.5) ml/min respectively. Inter and intra-observer reliability was excellent for majority of measurements. The mean coefficient of variation for inter observer diameter measurements was 1.2% and intra observer measurements were between 1.5% to 3.9% for both observers. Flow volume measurements performed using 3D printed materials resulted in realistic echogenicities mimicking biological tissues. Validity and reliability studies, within and between, observers showed acceptable results. Researchers and clinicians can use this model for further training and simulation.

Diameter measurements in three-dimensional printed flow phantom model of the carotid artery in preterm infants

Diameter form an integral part of blood flow measurement. This study aimed to explore different three-dimensional (3D) printed materials to develop flow phantom models of the carotid artery in preterm newborn infants and to investigate ideal diameter measurement points using ultrasound that reflected accurate lumen diameter measurement. Cerebral blood flow measurements data using Doppler ultrasound of the right common carotid artery from 21 randomly selected preterm infants were used to produce a 3D printed Doppler flow phantom model with three different vessel diameters. Diameters were measured by multiple observers blinded to phantom vessel characteristics and each other’s measurements. 9 measurement points were studied. Agreement between observers, inter and intra observer reliability and coefficient of variation (CoV) was examined. Of the 63 diameter measurements, 45 (71%) were performed on flow phantoms with vessel diameter of 0.196 cm. Bland-Altman plots revealed that measurement performed using leading edge to centre (mean bias 1.8% {95%LOA -4.1% to 7.7%}) and centre to trailing edge (mean bias 1.1% {95%LOA -5.4% to 7.8%}) resulted in the most accurate lumen diameter measurements. Inter and intra-observer reliability was excellent. The mean CoV for inter observer measurements was 1.7% and intra observer measurements was 1.6% and 1.8% for each observer. We successfully produced a 3D printed flow phantom model of the carotid artery in preterm infants and identified two measurement methods that result in reliable and accurate lumen diameter measurement. Researchers and clinicians can use this information for further studies involving ultrasound diameter measurements in small calibre vessels.

Compact circular polarized CPW antenna for WLAN and biomedical applications

A compact, circularly polarized, CPW-fed antenna is proposed for wearable applications in ISM Band (5.8 GHz). The antenna is based on DGS, where the ground plane is responsible for impedance matching. The 10 dB impedance of the proposed antenna varies from 5.39 GHz to 5.94 GHz. The circular stub introduced in the ground plane mitigates the surface current and enriches the 3 dB axial ratio from 5.73 GHz to 5.92 GHz. Proposed antenna exhibits the LHCP and RHCP pattern of circular polarization, the antenna can effectively work for biomedical and wearable applications. The antenna is analyzed on the skin phantom model and the SAR value obtained is 1.218 W/kg, which is below the maximum permissible level. The proposed antenna is also used for the detection of breast tumors.

Autonomous Intubation Robot System based on Visual Servoing and Hybrid Control

During COVID-19 and other pandemics, endotracheal intubation is an effective and common method to save patients as the virus causes lung fibrosis and thus patients are unable to breathe spontaneously. Medical staff need to insert a tube close to the patient’s mouth, thereby leading to a high risk of cross-infection. To protect medical staff, we propose an autonomous intubation robot system (AIRS). With the developed visual servoing and hybrid control method, the entire system can simulate doctors for satisfying repeatability and safety of intubation operations. This system includes a self-driving/teleoperation platform, two co-robot arms, a new multi-functional laryngoscope, force sensors, and several cameras. In the visual servoing part, we realize recognition and location of the patient’s face, medical devices, and main physiological structures to provide real-time navigation. In the hybrid control part, we establish an oral model, propose an offline planning method and PID controllers by combining force, vision, and motion, and apply Virtual Fixture to insert safely. AIRS's validation is with a phantom model under a 2-min operation. Our proposed robot is original and promising in the area of emergent medical robots. We will further validate AIRS in clinical applications and extend the developed techniques in other general treatments.

Autonomous Intubation Robot System based on Visual Servoing and Hybrid Control

During COVID-19 and other pandemics, endotracheal intubation is an effective and common method to save patients as the virus causes lung fibrosis and thus patients are unable to breathe spontaneously. Medical staff need to insert a tube close to the patient’s mouth, thereby leading to a high risk of cross-infection. To protect medical staff, we propose an autonomous intubation robot system (AIRS). With the developed visual servoing and hybrid control method, the entire system can simulate doctors for satisfying repeatability and safety of intubation operations. This system includes a self-driving/teleoperation platform, two co-robot arms, a new multi-functional laryngoscope, force sensors, and several cameras. In the visual servoing part, we realize recognition and location of the patient’s face, medical devices, and main physiological structures to provide real-time navigation. In the hybrid control part, we establish an oral model, propose an offline planning method and PID controllers by combining force, vision, and motion, and apply Virtual Fixture to insert safely. AIRS's validation is with a phantom model under a 2-min operation. Our proposed robot is original and promising in the area of emergent medical robots. We will further validate AIRS in clinical applications and extend the developed techniques in other general treatments.

Antenna design and fabrication for biotelemetry applications

<span>This research work assumes the role of designing a Micro-strip patch antenna that exists with in the band range of 402 MHz to 405 MHz, which was considered as medical implantable communication systems (MICS) band and can be possibly implanted at human body phantom model because of its flexiblility and lower radiation characteristics. CST Microwave studio was used for designing the patch antenna and the human body phantom model with the existence of homogeneous layers (fat, skin and muscle) and the final version was fabricated. Being highly flexible, FR4 was chosen as a substrate to maintain 0.5 mm thickness throughout. For the ground and patch, copper material was selected having thickness of 0.018 mm. For the ease of fabrication and biocompatibility, silicon was selected with the thickness of being 8 mm. Maximum specific absorption rate of the proposed antenna was obtained 0.588 W/Kg for 10g tissue. Various Parameters such as VSWR, S11, Radiation efficiency, Total efficiency were found 1.1889, -21.28 dB, <br /> -45.71 dB, -45.74 dB respectively inside body phantom that ensure the antenna design was efficiently and effectively suitable for biotelemetry system which is body implantable. After fabrication the value of S11 is found -12.43 dB in open space with 453 MHz frequency.</span>

Konnyaku jelly: A quick preparation and cost effective ultrasound-guided IV phantom model

Clinicians commonly place ultrasound-guided intravenous catheters in peripheral veins for the diagnostic and therapeutic treatments of patients. This procedural skill requires practice and static phantom models are a commonly used education tool. Several commercial models that simulate blood vessels within tissue are available; however, they can be expensive. There are many examples of “Do-It-Yourself” models proposed; however, many of these require time to create the model. Mixing water and gelatin to make a gelatinous material, and the time necessary to set and store the phantom may deter people from pursuing these options. We propose Konnyaku jelly, or “yam cake,” found in many Asian grocery stores, as the substrate to create a phantom model. When imaging with ultrasound, this model is similar to commercially available models, however the cost is less than $3.00 and preparation is about 5 min. We believe that Konnyaku jelly should be a more generally accepted homemade static model for phantom preparation.

PHANTOM MODEL OF DISTRIBUTION OF VIRAL OBJECTS IN A PANDEMIC. PART 3

The article states that the nature of the virus's interaction with objects during its spread in any environment is a significant problem. Therefore, taking into account the peculiarities of such a complex fractional composition of flows can make it possible to determine the nature of the interaction of the object, in particular biological, with complex particles of viral flows when touching. The author's previous works consider the peculiarities of the spread of viruses in the surrounding space of the pandanus zone of the object under the condition of a single fraction of the particle, ie in the near-surface layer. Of course, to better understand the nature of the interaction of viral flows with objects of possible infection, it is necessary to analyze the processes of virion’s touching to the cell surface of a biological object. The studied regularities of the occurrence of motion forces in environment’s space made it possible to determine the geometric parameters of the spread of viral formations near the object’s surface. The main purpose of this study was to continue to create a model of interaction of complex flows with different fractions that are carriers of viruses as material particles in the environment, in terms of modeling the motion and touching the surface of the object at different types of touch depending on their interaction. The mechanical movement of the virus during contact, rather than stages, as in biological processes, is considered. The nature of the interaction of complex viruses’s streams with objects of biological origin is modeled. To study the peculiarities of the interaction of the virion with the cell surface of a biological object, it is necessary to consider the flow complex of particles of different fractions, i.e. microstructures of virions that accompany drip suspension flows of body fluids and foreign dust particles. Thus, we can distinguish the motion of a complex of particles that comes into contact with object’s surface, as well as the possibility of breaking out individual microparticles, virions, which can emerge from the complex flow and propagate separately from others. At the same time, the dependences of the energy complex, which forms the flow of complex elements-particles of different fractions, which can take into account the range of flow propagation and features of motion kinematics, are determined. In further research, the phantom model of the propagation of fluxes of viral objects in space requires modeling the temporal parameters of the motion of fluxes of complex particles during the propagation to the object’s surface of various origins, including biological object.

Rectus Femoris Mimicking Ultrasound Phantom for Muscle Mass Assessment: Design, Research, and Training Application

Ultrasound has become widely used as a means to measure the rectus femoris muscle in the acute and chronic phases of critical illness. Despite its noninvasiveness and accessibility, its accuracy highly depends on the skills of the technician. However, few ultrasound phantoms for the confirmation of its accuracy or to improve technical skills exist. In this study, the authors created a novel phantom model and used it for investigating the accuracy of measurements and for training. Study 1 investigated how various conditions affect ultrasound measurements such as thickness, cross-sectional area, and echogenicity. Study 2 investigated if the phantom can be used for the training of various health care providers in vitro and in vivo. Study 1 showed that thickness, cross-sectional area, and echogenicity were affected by probe compression strength, probe angle, phantom compression, and varying equipment. Study 2 in vitro showed that using the phantom for training improved the accuracy of the measurements taken within the phantom, and Study 2 in vivo showed the phantom training had a short-term effect on improving the measurement accuracy in a human volunteer. The new ultrasound phantom model revealed that various conditions affected ultrasound measurements, and phantom training improved the measurement accuracy.