Academic literature on the topic 'Non-invasive portable device for measuring intracranial pressure'

Abstract Objective. The assessment of lung mechanics in horses is nowadays based on invasive methods that may require sedation. The forced oscillation technique (FOT) allows the non-invasive assessment of respiratory mechanics during spontaneous breathing, but current devices are complex, cumbersome, expensive, and difficult to be applied in horses. Approach. We developed a portable FOT device based on a novel approach in which the pressure waveforms are generated by a servo-controlled ducted fan. This new approach allows the design of devices that are more sturdy, compact, and portable compared to already existing approaches. The prototype includes 1) a small microcontroller-based electronic board for controlling the fan and measuring flow and pressure and 2) an optimized data processing algorithm. Main results. This device provides a maximum error of 0.06 cmH2O·s/L and 0.15 cmH2O·s/L in measuring respiratory resistance and reactance during in-vitro validation. A pilot study was also performed on three healthy horses and three horses with severe equine asthma (SEA) and it demonstrated good tolerability and feasibility of the new device. Total respiratory system resistance (R rs) and reactance (X rs) significantly differed (p < 0.05) between groups. At 5 Hz, R rs was 0.66 ± 0.02 cmH2O·s/L and 0.94 ± 0.07 cmH2O·s/L in healthy and in SEA, respectively. X rs 0.38 ± 0.02 cmH2O·s/L and −0.27 ± 0.05 cmH2O·s/L. Significance. This novel approach for applying FOT allowed the development of a small, affordable, and portable device for the non-invasive evaluation of respiratory mechanics in spontaneously breathing horses, providing a useful new tool for improving veterinary respiratory medicine. Moreover, our results provide supporting evidence of the value of this novel approach for developing portable FOT devices also for applications in humans.

A new portable measuring device for monitoring intraocular pressure with a non invasive system using a prototype of contact lens has been developed. The contact lens is based on a new organic flexible highly piezo-resisitive film sensor that is glued to the central hole of a lens. The measuring system is wire connected to the contact lens and incorporates user interface methods and a Bluetooth link for bi-directional wireless data transfer. The key design aspects of such architecture are discussed in this paper. The system is designed with an architecture that can be integrated in the future in order to be placed in the contact lens. The discrete system is used to validate the electronic measurement operation and the contact lens sensor (CLS). The measurement instrument can calibrate the differences of the nominal value of the sensor and measure resistances variations that are related to pressure variations. The measuring system and the contact lens sensor were tested with an eye phantom and with enucleated pig eyes by applying pressure changes between 7 to 32 mmHg recording the electrical changes with the portable device.

A low-cost, portable, unobtrusive and non-invasive system has been developed, capable of measuring human gait forces over a 16 how-period, and characterized and proven in limited trials. The device comprises a foam insole containing a coiled air-filled elastic tube whose internal pressure (which increases under load) is measured by a pressure gauge. This signal is recorded by a small data logger worn around the patient's waist, and subsequently downloaded to a personal computer for analysis. Typical results are presented. The system will initially be used with patients recovering from tibial and femoral shaft fractures to monitor their day-long load-bearing patterns. The results of this study will be used to investigate a causal relationship between load bearing and the extent and rate of osteoporosis, which will be measured separately. In the future, additional studies of gait, load bearing and general mobility of patients suffering from conditions such as arthritis and amputation will be undertaken.

An important function in the future healthcare system involves measuring a patient’s vital signs, transmitting the measured vital signs to a smart device or a management server, analyzing it in real-time, and informing the patient or medical staff. Internet of Medical Things (IoMT) incorporates information technology (IT) into patient monitoring device (PMD) and is developing traditional measurement devices into healthcare information systems. In the study, a portable ubiquitous-Vital (u-Vital) system is developed and consists of a Vital Block (VB), a small PMD, and Vital Sign Server (VSS), which stores and manages measured vital signs. Specifically, VBs collect a patient’s electrocardiogram (ECG), blood oxygen saturation (SpO2), non-invasive blood pressure (NiBP), body temperature (BT) in real-time, and the collected vital signs are transmitted to a VSS via wireless protocols such as WiFi and Bluetooth. Additionally, an efficient R-point detection algorithm was also proposed for real-time processing and long-term ECG analysis. Experiments demonstrated the effectiveness of measurement, transmission, and analysis of vital signs in the proposed portable u-Vital system.

Post-hemorrhagic ventricular dilatation (PHVD) is characterized by a build-up of cerebral spinal fluid (CSF) in the ventricles, which increases intracranial pressure and compresses brain tissue. Clinical interventions (i.e., ventricular taps, VT) work to mitigate these complications through CSF drainage; however, the timing of these procedures remains imprecise. This study presents Neonatal NeuroMonitor (NNeMo), a portable optical device that combines broadband near-infrared spectroscopy (B-NIRS) and diffuse correlation spectroscopy (DCS) to provide simultaneous assessments of cerebral blood flow (CBF), tissue saturation (StO2), and the oxidation state of cytochrome c oxidase (oxCCO). In this study, NNeMo was used to monitor cerebral hemodynamics and metabolism in PHVD patients selected for a VT. Across multiple VTs in four patients, no significant changes were found in any of the three parameters: CBF increased by 14.6 ± 37.6% (p = 0.09), StO2 by 1.9 ± 4.9% (p = 0.2), and oxCCO by 0.4 ± 0.6 µM (p = 0.09). However, removing outliers resulted in significant, but small, increases in CBF (6.0 ± 7.7%) and oxCCO (0.1 ± 0.1 µM). The results of this study demonstrate NNeMo’s ability to provide safe, non-invasive measurements of cerebral perfusion and metabolism for neuromonitoring applications in the neonatal intensive care unit.

Background Wellness devices for health tracking have gained popularity in recent years. Additionally, portable and readily accessible wellness devices have several advantages when compared to traditional medical devices found in clinical environments The VitalWellness device is a portable wellness device that can potentially aide vital sign measuring for those interested in tracking their health. Objective In this diagnostic accuracy study, we evaluated the performance of the VitalWellness device, a wireless, compact, non-invasive device that measures four vital signs (blood pressure (BP), heart rate (HR), respiratory rate (RR), and body temperature using the index finger and forehead. Methods Volunteers age ≥18 years were enrolled to provide blood pressure (BP), heart rate (HR), respiratory rate (RR), and body temperature. We recruited participants with vital signs that fell within and outside of the normal physiological range. A sub-group of eligible participants were asked to undergo an exercise test, aerobic step test and/or a paced breathing test to analyze the VitalWellness device’s performance on vital signs outside of the normal physiological ranges for HR and RR. Vital signs measurements were collected with the VitalWellness device and FDA-approved reference devices. Mean, standard deviation, mean difference, standard deviation of difference, standard error of mean difference, and correlation coefficients were calculated for measurements collected; these measurements were plotted on a scatter plot and a Bland-Altman plot. Sensitivity analyses were performed to evaluate the performance of the VitalWellness device by gender, skin color, finger size, and in the presence of artifacts. Results 265 volunteers enrolled in the study and 2 withdrew before study completion. Majority of the volunteers were female (62%), predominately white (63%), graduated from college or post college (67%), and employed (59%). There was a moderately strong linear relationship between VitalWellness BP and reference BP (r=0.7, P<.05) and VitalWellness RR and reference RR measurements (r=0.7, P<.05). The VitalWellness HR readings were significantly in line with the reference HR readings (r=0.9, P<.05). There was a weaker linear relationship between VitalWellness temperature and reference temperature (r=0.3, P<.05). There were no differences in performance of the VitalWellness device by gender, skin color or in the presence of artifacts. Finger size was associated with differential performance for RR. Conclusions Overall, the VitalWellness device performed well in taking BP, HR, and RR when compared to FDA-approved reference devices and has potential serve as a wellness device. To test adaptability and acceptability, future research may evaluate user’s interactions and experiences with the VitalWellness device at home. In addition, the next phase of the study will evaluate transmitting vital sign information from the VitalWellness device to an online secured database where information can be shared with HCPs within seconds of measurement.

Background Wellness devices for health tracking have gained popularity in recent years. Additionally, portable and readily accessible wellness devices have several advantages when compared to traditional medical devices found in clinical environments. Building tools for patients to manage their health independently may benefit their health in the long run by improving health care providers’ (HCPs) awareness of their patients’ health information outside of the clinic. Increased access to portable wellness devices that track vital signs may increase how patients and HCPs track and monitor chronic conditions which can improve health outcomes. The VitalWellness is a portable wellness device that can potentially aid vital sign measuring for those interested in tracking their health. Objective In this diagnostic accuracy study, we evaluated the clinical performance of the VitalWellness, a wireless, compact, non-invasive device that measures four vital signs using the index finger and forehead against reference vital signs devices used in the hospital setting. Methods Volunteers age ≥18 years were enrolled to provide blood pressure (BP), heart rate (HR), respiratory rate (RR), and body temperature. We recruited volunteers with vital signs that fell within and outside of the normal physiological range, depending on the measurements they consented to undergo. A subgroup of eligible volunteers were asked to undergo an exercise test, aerobic step test and/or a paced breathing test to analyze the VitalWellness device's performance on vital signs outside of the normal physiological ranges for HR and RR. Vital signs measurements were collected with the VitalWellness device and FDA-approved reference devices. Mean, standard deviation, mean difference, standard deviation of difference, standard error of mean difference, and correlation coefficients were calculated for measurements collected; these measurements were plotted on a scatter plot and a Bland-Altman plot. Sensitivity analyses were performed to evaluate the performance of the VitalWellness device by gender, skin color, finger size, and in the presence of artifacts. Results We enrolled 265 volunteers in the study and 2 withdrew before study completion. The majority of volunteers were female (62%), predominately white (63%), graduated from college or post college (67%), and employed (59%). There was a moderately strong linear relationship between VitalWellness BP and reference BP (r=0.7, P<.05) and bewteen VitalWellness RR and reference RR measurements (r=0.7, P<.05). The VitalWellness HR readings were significantly in line with the reference HR readings (r=0.9, P<.05). There was a weaker linear relationship between VitalWellness temperature and reference temperature (r=0.3, P<.05). There were no differences in performance of the VitalWellness device by gender, skin color or in the presence of artifacts. Finger size was associated with differential performance for RR. Conclusions Overall, the VitalWellness device performed well in taking BP, HR and RR when compared to FDA-approved reference devices and has potential serve as a wellness device. To test adaptability and acceptability, future research may evaluate user’s interactions and experiences with the VitalWellness device at home. In addition, the next phase of the study will evaluate transmitting vital sign information from the VitalWellness device to an online secured database where information can be shared with HCPs within seconds of measurement.

TPS9106 Background: Tumor Treating Fields (TTFields) are non-invasive regional anti-mitotic treatment modality, based on low intensity alternating electric fields. Efficacy of TTFields in non-small cell lung cancer (NSCLC) has been demonstrated in multiple in vitro and in vivo models, and in a phase I/II clinical study. TTFields treatment to the brain was shown to be safe and to extend overall survival in newly-diagnosed glioblastoma patients. Methods: 270 patients with 1-10 brain metastases (BM) from NSCLC will be randomized in a ratio of 1:1 to receive stereotactic radio surgery (SRS) followed by either TTFields or supportive care alone. Patients are followed-up every two months until 2nd cerebral progression. Patients in the control arm may cross over to receive TTFields at the time of 2st cerebral progression. Objectives: To test the efficacy, safety and neurocognitive outcomes of TTFields in this patient population. Endpoints: Time to 1st cerebral progression based on the RANO-BM Criteria or neurological death (primary); time to neurocognitive failure based on the following tests: HVLT, COWAT and TMT; overall survival; radiological response rate; quality of life; adverse events severity and frequency (secondary). Main eligibility criteria: Karnofsky performance status (KPS) of 70 or above, 1 inoperable or 2-10 brain lesions amenable to SRS, optimal standard therapy for the extracranial disease, no brain-directed therapy, no signs of significantly increased intracranial pressure, no electronic implantable devices in the brain. Treatment: Continuous TTFields at 150 kHz for at least 18 hours per day will be applied to the brain within 7 days of SRS. The treatment system is a portable medical device allowing normal daily activities. The device delivers TTFields to the brain using 4 Transducer Arrays, which may be covered by a wig or a hat for cosmetic reasons. Patients will receive the best standard of care for their systemic disease. Statistical Considerations: This is a prospective, randomized, multicenter study for 270 patients. The sample size was calculated using a log-rank test (based on Lakatos 1988 and 2002) and has 80% power at a two sided alpha of 0.05 to detect a hazard ratio of 0.57. Clinical trial information: NCT02831959.

Обсяг роботи становить 56 сторінок, міститься 22 ілюстрації, 14 таблиць. Загалом опрацьовано 46 джерел. На сьогодні у ряді досліджень доведено, що довготривале спостереження за значеннями ВЧТ сприяє покращенню постоперативних результатів і запобіганню крововиливам і набрякам. Проте прилади, які наразі використовуються в сучасній медицині для цього, є стаціонарними та великогабаритними і можуть призводити до ряду ускладнень. Очевидно, коли пацієнта вже можна виписувати з лікарні, але ще доволі високий ризик повторних крововиливів та набряків, неможливо здійснювати моніторинг за допомогою цих пристроїв. Існує гостра потреба у бездротовій неінвазивній системі для спостереження за ІКТ для спостереження за темпами реабілітації пацієнтів та запобігання постоперативних ускладнень. Досліджено важливість постійного, довготривалого моніторингу внутрішньочерепного тиску (ВЧТ) і проблеми в цій сфері. На основі визначених складнощів і потреб нейрохірургії розроблено концепцію портативного неінвазивного приладу для опосередкованого вимірювання інтракраніального тиску через яремний. За прототип розглянуто патент «Method and apparatus for noninvasive monitorng of intracranial pressure», в якому було вдосконалено блок вимірювання таким чином, щоб в подальшому пристрій став придатним до портативного неінвазивного моніторингу ВЧТ.
The volume of the work is 56 pages, contains 22 illustrations, 14 tables. A total of 46 sources were processed. Nowadays a number of studies have shown that long-term monitoring of ICP values improves postoperative outcomes and prevents hemorrhage and edema. But the devices currently used in modern medicine for this purpose are stationary, large and can lead to a number of complications. Obviously, when a patient can be discharged from the hospital, but there is still a high risk of recurrent hemorrhage and edema, it is impossible to monitor with these devices. There is an urgent need for a wireless non-invasive ICP monitoring system to monitor the pace of patient rehabilitation and prevent postoperative complications. The importance of continuous, long-term monitoring of intracranial pressure (ICP) and problems in this area have been studied in this thesis. The concept of a portable non-invasive device for indirect measurement of intracranial pressure through the jugular is based on the identified complexities and needs of neurosurgery. The patent "Method and apparatus for noninvasive monitoring of intracranial pressure" was considered as a prototype, in which the measuring unit was improved so that in the future the device became suitable for portable non-invasive monitoring of ICP.

Abstract Traumatic brain injury (TBI) has been considered a precarious health issue especially within the military population. Research has shown that early treatment of TBI could reduce possible neurocognitive injury. However, the nature of military triage has created challenges for early TBI detection. Intracranial pressure (ICP), which is used as a biomarker of outcomes in TBI, is not only expensive to measure but is also invasive and requires specialized surgical and procedural skills. Episcleral venous pressure (EVP) was proven to be a good alternative biomarker to ICP. However, the current technology in measuring EVP is not portable, and requires a skilled operator with a slit-lamp for testing. Moreover, the measurement is highly subjective and depends on the operator’s skill and technique. Therefore, there is a critical need for alternative technology for non-clinical TBI diagnosis. In this paper, we present an improved venomanometer design for measuring EVP in the field.

The effects of mis-positioning a newly-designed noninvasive, cuffless blood pressure sensor are thoroughly investigated via simulation and analysis on a 3D fluid-solid-electric finite element model. A subsequent optimal design of this blood pressure is conducted based on the aforementioned mis-positioning effects. A highly-accurate, non-invasive, cuffless blood pressure (BP) sensor was successfully developed recently for an effective personal monitoring device on blood pressures. This new small-sized, portable blood pressure sensor is able to offer continuous BP measurements. The availability of continuous blood pressures are important for monitoring and evaluating personal cardiovascular systems. The sensor contains a strain-sensitive electrode encapsulated by flexible polymer. As the sensor placed on the position right on the top of the center of the wrist pulsation area, the deflection of the sensor induces the resistance changes of the electrode. By measuring the changes in electrode resistance, the level of pulsation is successfully quantified. Subsequent calculation based in this measurement can lead to fair estimates on blood pressures. However, as the sensor is placed on the wrist area where pulsation occurs, the mis-positioning of the sensor to the desired location, the center of the pulsation area, is inevitable. This study is dedicated to investigate the effects of the mis-positioning via a 3D finite element model. A new 3D fluid-solid-electro coupling interaction finite element model of the wrist is built for predicting the vibration of radial artery and then diastolic and systolic blood pressures. The FEM includes sensor of gel capsule and strain-sensing electrodes, radial artery, blood, radius bones, tendon, muscles and the front-end readout circuit. The FEM is the multi physics FEM with fluid, solid and electric. The section of wrist is constructed from magnetic resonance imaging (MRI) and the length of the FEM is 40mm. The complete 3D FEM model successfully simulated the vibration of skin surface and the sensor module. The diastolic and systolic blood pressures can be accurately predicted by the simulated output resistance. The pulsation levels due to varied mis-positionings are simulated by the built model, and simulation results are successfully validated by experiments. It is found that due to the unsymmetrical geometry of the wrist, the pulsation levels are also varied in an un-symmetric fashion with the mis-positionings in different directions. The maximum output of the BP sensor occurs when the sensor is placed ±3 mm away from the center of the pulsation area, while the sensor output remain valid for subsequent signal processing as the sensor is placed within ±5 mm from the pulsation center. Considering the inevitable mis-positionings by all possible users in different genders and ages, the sizes of the sensors are successfully optimized for satisfactory average signal quality over all possible users.