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1.
Technology (Singap World Sci) ; 7(3-4): 98-107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32292800

RESUMO

Obtaining venous access for blood sampling or intravenous (IV) fluid delivery is an essential first step in patient care. However, success rates rely heavily on clinician experience and patient physiology. Difficulties in obtaining venous access result in missed sticks and injury to patients, and typically require alternative access pathways and additional personnel that lengthen procedure times, thereby creating unnecessary costs to healthcare facilities. Here, we present the first-in-human assessment of an automated robotic venipuncture device designed to safely perform blood draws on peripheral forearm veins. The device combines ultrasound imaging and miniaturized robotics to identify suitable vessels for cannulation and robotically guide an attached needle toward the lumen center. The device demonstrated results comparable to or exceeding that of clinical standards, with a success rate of 87% on all participants (n = 31), a 97% success rate on nondifficult venous access participants (n = 25), and an average procedure time of 93 ± 30 s (n = 31). In the future, this device can be extended to other areas of vascular access such as IV catheterization, central venous access, dialysis, and arterial line placement.

2.
Technology (Singap World Sci) ; 6(3-4): 79-100, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30713991

RESUMO

Cancer is a devastating disease that takes the lives of hundreds of thousands of people every year. Due to disease heterogeneity, standard treatments, such as chemotherapy or radiation, are effective in only a subset of the patient population. Tumors can have different underlying genetic causes and may express different proteins in one patient versus another. This inherent variability of cancer lends itself to the growing field of precision and personalized medicine (PPM). There are many ongoing efforts to acquire PPM data in order to characterize molecular differences between tumors. Some PPM products are already available to link these differences to an effective drug. It is clear that PPM cancer treatments can result in immense patient benefits, and companies and regulatory agencies have begun to recognize this. However, broader changes to the healthcare and insurance systems must be addressed if PPM is to become part of standard cancer care.

3.
J Med Device ; 11(4): 0410081-410087, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29230256

RESUMO

Preclinical testing in rodent models is a ubiquitous part of modern biomedical research and commonly involves accessing the venous bloodstream for blood sampling and drug delivery. Manual tail vein cannulation is a time-consuming process and requires significant skill and training, particularly since improperly inserted needles can affect the experimental results and study outcomes. In this paper, we present a miniaturized, robotic medical device for automated, image-guided tail vein cannulations in rodent models. The device is composed of an actuated three degrees-of-freedom (DOFs) needle manipulator, three-dimensional (3D) near-infrared (NIR) stereo cameras, and an animal holding platform. Evaluating the system through a series of workspace simulations and free-space positioning tests, the device exhibited a sufficient work volume for the needle insertion task and submillimeter accuracy over the calibration targets. The results indicate that the device is capable of cannulating tail veins in rodent models as small as 0.3 mm in diameter, the smallest diameter vein required to target.

4.
IEEE Trans Ind Electron ; 64(2): 1626-1635, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28111492

RESUMO

Robotic systems have slowly entered the realm of modern medicine; however, outside the operating room, medical robotics has yet to be translated to more routine interventions such as blood sampling or intravenous fluid delivery. In this paper, we present a medical robot that safely and rapidly cannulates peripheral blood vessels-a procedure commonly known as venipuncture. The device uses near-infrared and ultrasound imaging to scan and select suitable injection sites, and a 9-DOF robot to insert the needle into the center of the vessel based on image and force guidance. We first present the system design and visual servoing scheme of the latest generation robot, and then evaluate the performance of the device through workspace simulations and free-space positioning tests. Finally, we perform a series of motion tracking experiments using stereo vision, ultrasound, and force sensing to guide the position and orientation of the needle tip. Positioning experiments indicate sub-millimeter accuracy and repeatability over the operating workspace of the system, while tracking studies demonstrate real-time needle servoing in response to moving targets. Lastly, robotic phantom cannulations demonstrate the use of multiple system states to confirm that the needle has reached the center of the vessel.

5.
Med Image Comput Comput Assist Interv ; 9902: 388-396, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27981261

RESUMO

This paper presents a portable imaging device designed to detect peripheral blood vessels for cannula insertion that are otherwise difficult to visualize beneath the skin. The device combines near infrared stereo vision, ultrasound, and real-time image analysis to map the 3D structure of subcutaneous vessels. We show that the device can identify adult forearm vessels and be used to guide manual insertions in tissue phantoms with increased first-stick accuracy compared to unassisted cannulation. We also demonstrate that the system may be coupled with a robotic manipulator to perform automated, image-guided venipuncture.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Cateterismo Periférico/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Espectroscopia de Luz Próxima ao Infravermelho , Ultrassonografia de Intervenção/métodos , Adulto , Algoritmos , Cateterismo Periférico/instrumentação , Humanos , Agulhas , Imagens de Fantasmas , Flebotomia/instrumentação , Flebotomia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia de Intervenção/instrumentação
6.
Med Phys ; 43(6): 3117-3131, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27277058

RESUMO

PURPOSE: This paper describes the design, fabrication, and characterization of multilayered tissue mimicking skin and vessel phantoms with tunable mechanical, optical, and acoustic properties. The phantoms comprise epidermis, dermis, and hypodermis skin layers, blood vessels, and blood mimicking fluid. Each tissue component may be individually tailored to a range of physiological and demographic conditions. METHODS: The skin layers were constructed from varying concentrations of gelatin and agar. Synthetic melanin, India ink, absorbing dyes, and Intralipid were added to provide optical absorption and scattering in the skin layers. Bovine serum albumin was used to increase acoustic attenuation, and 40 µm diameter silica microspheres were used to induce acoustic backscatter. Phantom vessels consisting of thin-walled polydimethylsiloxane tubing were embedded at depths of 2-6 mm beneath the skin, and blood mimicking fluid was passed through the vessels. The phantoms were characterized through uniaxial compression and tension experiments, rheological frequency sweep studies, diffuse reflectance spectroscopy, and ultrasonic pulse-echo measurements. Results were then compared to in vivo and ex vivo literature data. RESULTS: The elastic and dynamic shear behavior of the phantom skin layers and vessel wall closely approximated the behavior of porcine skin tissues and human vessels. Similarly, the optical properties of the phantom tissue components in the wavelength range of 400-1100 nm, as well as the acoustic properties in the frequency range of 2-9 MHz, were comparable to human tissue data. Normalized root mean square percent errors between the phantom results and the literature reference values ranged from 1.06% to 9.82%, which for many measurements were less than the sample variability. Finally, the mechanical and imaging characteristics of the phantoms were found to remain stable after 30 days of storage at 21 °C. CONCLUSIONS: The phantoms described in this work simulate the mechanical, optical, and acoustic properties of human skin tissues, vessel tissue, and blood. In this way, the phantoms are uniquely suited to serve as test models for multimodal imaging techniques and image-guided interventions.

7.
Rep U S ; 2016: 514-520, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28239509

RESUMO

Diagnostic blood testing is the most prevalent medical procedure performed in the world and forms the cornerstone of modern health care delivery. Yet blood tests are still predominantly carried out in centralized labs using large-volume samples acquired by manual venipuncture, and no end-to-end solution from blood draw to sample analysis exists today. Our group is developing a platform device that merges robotic phlebotomy with automated diagnostics to rapidly deliver patient information at the site of the blood draw. The system couples an image-guided venipuncture robot, designed to address the challenges of routine venous access, with a centrifuge-based blood analyzer to obtain quantitative measurements of hematology. In this paper, we first present the system design and architecture of the integrated device. We then perform a series of in vitro experiments to evaluate the cannulation accuracy of the system on blood vessel phantoms. Next, we assess the effects of vessel diameter, needle gauge, flow rate, and viscosity on the rate of sample collection. Finally, we demonstrate proof-of-concept of a white cell assay on the blood analyzer using in vitro human samples spiked with fluorescently labeled microbeads.

8.
Anal Methods ; 8(47): 8272-8279, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28446924

RESUMO

Centrifugal microfluidics has received much attention in the last decade for the automation of blood testing at the point-of-care, specifically for the detection of chemistries, proteins, and nucleic acids. However, the detection of common blood cells on-disc, particularly leukocytes, remains a challenge. In this paper, we present two analytical methods for enumerating leukocytes on a centrifugal platform using a custom-built fluorescent microscope, acridine orange nuclear staining, and image processing techniques. In the first method, cell analysis is performed in glass capillary tubes; in the second, acrylic chips are used. A bulk-cell analysis approach is implemented in both cases where the pixel areas of fractionated lymphocyte/monocyte and granulocyte layers are correlated with cell counts. Generating standard curves using porcine blood sample controls, we observed strong linear fits to measured cell counts using both methods. Analyzing the pixel intensities of the fluorescing white cell region, we are able to differentiate lymphocytes from monocytes via pixel clustering, demonstrating the capacity to perform a 3-part differential. Finally, a discussion of pros and cons of the bulk-cell analysis approach concludes the paper.

9.
IEEE Trans Robot ; 31(4): 1044-1053, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26257588

RESUMO

Accessing the venous bloodstream to deliver fluids or obtain a blood sample is the most common clinical routine practiced in the U.S. Practitioners continue to rely on manual venipuncture techniques, but success rates are heavily dependent on clinician skill and patient physiology. In the U.S., failure rates can be as high as 50% in difficult patients, making venipuncture the leading cause of medical injury. To improve the rate of first-stick success, we have developed a portable autonomous venipuncture device that robotically servos a needle into a suitable vein under image guidance. The device operates in real time, combining near-infrared and ultra-sound imaging, image analysis, and a 7-degree-of-freedom (DOF) robotic system to perform the venipuncture. The robot consists of a 3-DOF gantry to image the patient's peripheral forearm veins and a miniaturized 4-DOF serial arm to guide the cannula into the selected vein under closed-loop control. In this paper, we present the system architecture of the robot and evaluate the accuracy and precision through tracking, free-space positioning, and in vitro phantom cannulation experiments. The results demonstrate sub-millimeter accuracy throughout the operating workspace of the manipulator and a high rate of success when cannulating phantom veins in a skin-mimicking tissue model.

10.
Rep U S ; 2015: 2633-2638, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26779381

RESUMO

Venipuncture is the most common invasive medical procedure performed in the United States and the number one cause of hospital injury. Failure rates are particularly high in pediatric and elderly patients, whose veins tend to deform, move, or roll as the needle is introduced. To improve venipuncture accuracy in challenging patient populations, we have developed a portable device that autonomously servos a needle into a suitable vein under image guidance. The device operates in real time, combining near-infrared and ultrasound imaging, computer vision software, and a 9 degrees-of-freedom robot that servos the needle. In this paper, we present the kinematic and mechanical design of the latest generation robot. We then investigate in silico and in vitro the mechanics of vessel rolling and deformation in response to needle insertions performed by the robot. Finally, we demonstrate how the robot can make real-time adjustments under ultrasound image guidance to compensate for subtle vessel motions during venipuncture.

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