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Safe quality control of radiotherapy treatments lies in reliable dosimetric sensors. Currently, ionization chambers and solid-state diodes along with electrometers as readout systems are accomplishing this task. In this work, we present a well-known and low-cost semiconductor sensor, the light-dependent resistor (LDR), as an alternative to the existing sensing devices for dosimetry. To demonstrate this, a complete characterization of the response to radiation of commercial LDRs has been conducted in terms of sensitivity, reproducibility and thermal correction under different bias voltages. Irradiation sessions have been applied under the common conditions in radiotherapy treatments using a hospital linear accelerator. Moreover, the same electrometer used for the ionization chamber has also been successfully used for LDRs. In comparison with the sensitivity achieved for the ionization chamber (0.2 nC/cGy at 400 V bias voltage), higher sensitivities have been measured for the proposed LDRs, ranging from 0.24 to 1.04 nC/cGy at bias voltages from 30 to 150 V, with a reproducibility uncertainty among samples of around 10%. In addition, LDR temperature dependence has been properly modeled using the simple thermistor model so that an easy thermal drift correction of dose measurements can be applied. Therefore, experimental results show that LDRs can be a reliable alternative to dosimetric sensors with the advantages of low size, affordable cost and the fact that it could be adopted with minimal changes in routine dosimetry quality control since the same readout system is fully compatible.

Objectives: To investigate (1) Finnish pharmacy customers' familiarity with My Kanta, the national online service for viewing electronic prescriptions (ePrescriptions), (2) how commonly My Kanta is used, (3) who the typical users are, and (4) users' experiences of the usability of My Kanta., Method: A survey was conducted among pharmacy customers (aged ≥18) purchasing medicines for themselves. Questionnaires (N=2915) were distributed from 18 community pharmacies across Finland in autumn 2015. The data obtained was stored in SPSS for Windows and subjected to descriptive analysis, chi-square tests and logistic regression analysis., Results: In total, 1288 respondents were included (response rate 44%). Most (62%) of the customers were familiar with My Kanta. The majority of them (78%) were using it to view their ePrescriptions. My Kanta was perceived as clear, easy to use and to provide a good overall picture of the prescribed medications. Familiarity with My Kanta was associated with a higher education than basic school, regular use of prescription medicines, and sufficient information received about ePrescriptions. Men used My Kanta more often than women. Respondents aged 75 or older were less likely to be familiar with and to use the service compared to 18-34year olds., Conclusions: Most of the Finnish pharmacy customers were familiar with the national online service, My Kanta, for viewing ePrescriptions. Service users perceived it as easy to use and beneficial in managing their overall medication. Customers under 75, those educated beyond basic school, those using prescription medicines regularly, and those who had obtained sufficient information about ePrescriptions were most likely to be familiar with My Kanta. Men and customers under 75 were the typical users of the service. Some customers, however, were unaware of the service, or unable or reluctant to use it., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

The number of patients with noncardiac implantable electronic devices is increasing, and the absence of perioperative management standards, guidelines, practice parameters, or expert consensus statements presents clinical challenges. A 69-year-old woman presented for latissimus dorsi breast reconstruction. The patient had previously undergone implantation of a spinal cord stimulator, a gastric pacemaker, a sacral nerve stimulator, and an intrathecal morphine pump. After consultation with device manufacturers, the devices with patient programmability were switched off. Bipolar cautery was used intraoperatively. Postoperatively, all devices were interrogated to ensure appropriate functioning before home discharge. Perioperative goals include complete preoperative radiologic documentation of device component location, minimizing electromagnetic interference, and avoiding mechanical damage to implanted device components.

This paper presents a novel simple method to identify and remove systematic interference in battery powered physiological monitoring devices. This interference is very typically introduced via fluctuations in the power supply voltage, caused by the nonideal output resistance of small batteries, when a transceiver chip changes operating modes. The proposed method is designed to have low computational complexity in order to potentially allow for low cost, real-time implementations on low-power-based platforms, either in the system front or back end. Additionally, the paper provides guidelines on how to choose some of the operating conditions of the transceiver in order to minimize the effect of the interference through the application of the proposed method. Overall, successful performance is illustrated with experimental results obtained from an acoustic monitoring system, since this is considered to have specifications which are representative of most physiological monitoring devices.

The long-term stability of three clinical electronic portal imaging devices (EPIDs) was studied to determine if longer times between calibrations can be justified. This would make alternatives to flood-field calibration of EPIDs clinically feasible, allowing for more effective use of EPIDs for dosimetry. Images were acquired monthly for each EPID as part of regular clinical quality assurance over a time period of approximately 3 years. The images were analysed to determine (1) the long-term stability of the EPID positioning system, (2) the dose response of the central pixels and (3) the long term stability of each pixel in the imager. The position of the EPID was found to be very repeatable with variations less than 0.3 pixels (0.27 mm) for all imagers (1 standard deviation). The central axis dose response was found to reliably track ion chamber measurements to better than 0.5%. The mean variation in pixel response (1 standard deviation), averaged over all pixels in the EPID, was found to be at most 0.6% for the three EPIDs studied over the entire period. More than 99% of pixels in each EPID showed less than 1% variation. Since the EPID response was found to be very stable over long periods of time, an annual calibration should be sufficient in most cases. More complex dosimetric calibrations should be clinically feasible.

In the past decade, cardiac pacing devices (either permanent pacemakers or Implanted Cardioverter Defibrillators) have become increasingly common in patients with heart failure. The manner in which the device is programmed to pace the heart can have significant implications on cardiac hemodynamics, both positive and negative. As such, in patients hospitalized with acute heart failure who have cardiac pacing devices, the clinician should note whether the programming of the device could be contributing to the patient's symptoms, and whether further programming changes could be made to improve the patient's clinical status. As of this date, there are no consensus guidelines available for the management of pacemaker programming in acute heart failure. This review article will discuss the physiologic implications of several parameters of pacemaker programming on heart failure, including the degree of RV pacing, the programmed atrioventricular (AV) interval, and the programmed interventricular pacing delay in patients with cardiac resynchronization therapy (CRT) devices. Based on the available data on the above parameters, this article will then propose a general algorithmic approach to the evaluation and management of patients with pacing devices who are hospitalized with acute heart failure.

Background: Even though technological progress has provided us with more and more sophisticated equipment for making goniometric measurements, the most commonly used clinical tools are still the universal goniometer and, to a lesser extent, the inclinometer. There is, however, no published study so far that uses an inclinometer for measurements in children with cerebral palsy (CP). The objective of this study was two-fold: to independently assess the intra and inter-examiner reliability for measuring the hip abduction range of motion in children with CP using two different instruments, the universal two-axis goniometer and electronic inclinometer. A pool of 5 examiners with different levels of experience as paediatric physiotherapists participated. The study did not compare both instruments because the measurement procedure and the hip position were different for each., Methods: A prospective, observational study of goniometery was carried out with 14 lower extremities of 7 children with spastic CP. The inclinometer study was carried out with 8 lower extremities of 4 children with spastic CP. This study was divided into two independent parts: a study of the reliability of the hip abduction range of motion measured with a universal goniometer (hip at 0° flexion) and with an electronic inclinometer (hip at 90° flexion). The Intraclass Correlation Coefficient (ICC) was calculated to analyse intra and inter-examiner agreement for each instrument., Results: For the goniometer, the intra-examiner reliability was excellent (>0.80), while the inter-examiner reliability was low (0.375 and 0.475). For the inclinometer, both the intra-examiner (0.850-0.975) and inter-examiner reliability were excellent (0.965 and 0.979)., Conclusions: The inter-examiner reliability for goniometric measurement of hip abduction in children with CP was low, in keeping with other results found in previous publications. The inclinometer has proved to be a highly reliable tool for measuring the hip abduction range of motion in children with CP, which opens up new possibilities in this field, despite having some measurement limitations.

Traditionally, e-Health solutions were located at the point of care (PoC), while the new ubiquitous user-centered paradigm draws on standard-based personal health devices (PHDs). Such devices place strict constraints on computation and battery efficiency that encouraged the International Organization for Standardization/IEEE11073 (X73) standard for medical devices to evolve from X73PoC to X73PHD. In this context, low-voltage low-power (LV-LP) technologies meet the restrictions of X73PHD-compliant devices. Since X73PHD does not approach the software architecture, the accomplishment of an efficient design falls directly on the software developer. Therefore, computational and battery performance of such LV-LP-constrained devices can even be outperformed through an efficient X73PHD implementation design. In this context, this paper proposes a new methodology to implement X73PHD into microcontroller-based platforms with LV-LP constraints. Such implementation methodology has been developed through a patterns-based approach and applied to a number of X73PHD-compliant agents (including weighing scale, blood pressure monitor, and thermometer specializations) and microprocessor architectures (8, 16, and 32 bits) as a proof of concept. As a reference, the results obtained in the weighing scale guarantee all features of X73PHD running over a microcontroller architecture based on ARM7TDMI requiring only 168 B of RAM and 2546 B of flash memory.

In deep brain stimulation (DBS) surgery, after intracranial lead implantation, lead caps are tunneled into the subgaleal space for later connection to internal pulse generator (IPG) extension wires. In the subsequent IPG implantation procedure, the lead cap must be localized by palpation in order to plan an incision in the scalp to complete this connection. However, if the IPG implantation is done the same day as the intracranial lead implantation, palpation of the lead cap may be challenging in a thick or postoperatively edematous scalp. Manufacturers suggest using fluoroscopy in these instances, but fluoroscopy provides poor soft tissue visualization, requires further unnecessary radiation exposure to both the patient and the surgical team, and can be cumbersome. Portable ultrasound (US) machines are readily available in many operating rooms, and can be used to easily and accurately localize the lead cap prior to IPG implantation., (© Georg Thieme Verlag KG Stuttgart · New York.)

Introduction: Automated hand-held nerve conduction study (NCS) devices are being marketed for use in the diagnosis of lumbosacral radiculopathy (LSR). In this study we compared the specificity and sensitivity of a hand-held NCS device for the detection of LSR with standard electrodiagnostic study (EDX)., Methods: Fifty patients referred to a tertiary referral electromyography (EMG) laboratory for testing of predominantly unilateral leg symptoms (weakness, sensory complaints, and/or pain) were included in the investigation. Twenty-five normal "control" subjects were later recruited to calculate the specificity of the automated protocol. All patients underwent standard EDX and automated testing., Results: Raw NCS data were comparable for both techniques; however, computer-generated interpretations delivered by the automated device showed high sensitivity with low specificity (i.e., many false positives) in both symptomatic patients and normal controls., Conclusions: The automated device accurately recorded raw data, but the interpretations provided were overly sensitive and lacked the specificity necessary for a screening or diagnostic examination.

The mechanisms of nerve conduction block induced by direct current (DC) were investigated using a lumped circuit model of the myelinated axon based on Frankenhaeuser-Huxley (FH) model. Four types of nerve conduction block were observed including anodal DC block, cathodal DC block, virtual anodal DC block, and virtual cathodal DC block. The concept of activating function was used to explain the blocking locations and relation between these different types of nerve block. Anodal/cathodal DC blocks occurred at the axonal nodes under the block electrode, while virtual anodal/cathodal DC blocks occurred at the nodes several millimeters away from the block electrode. Anodal or virtual anodal DC block was caused by hyperpolarization of the axon membrane resulting in the failure of activating sodium channels by the arriving action potential. Cathodal or virtual cathodal DC block was caused by depolarization of the axon membrane resulting in inactivation of the sodium channel. The threshold of cathodal DC block was lower than anodal DC block in most conditions. The threshold of virtual anodal/cathodal blocks was about three to five times higher than the threshold of anodal/cathodal blocks. The blocking threshold was decreased with an increase of axonal diameter, a decrease of electrode distance to axon, or an increase of temperature. This simulation study, which revealed four possible mechanisms of nerve conduction block in myelinated axons induced by DC current, can guide future animal experiments as well as optimize the design of electrodes to block nerve conduction in neuroprosthetic applications.

Background: The auscultatory method is used as the reference standard in all prevalent protocols for validation of noninvasive blood pressure measuring devices, and a validation study is essentially based on the comparison between the device and observer measurements. Thus, the objectivity and accuracy of observer measurements are crucial to the validation result., Methods: To provide observers with more objective information about an auscultatory measurement so that sufficient information to make measurements with greater potential objectivity and accuracy can be available, a computerized data acquisition and analysis system has been developed. It cannot only acquire and store Korotkoff sound, cuff pressure, and oscillometric pulse signals, as well as the sphygmomanometer image, but it also can display the waveforms of the three signals and the sphygmomanometer video while playing the synchronous Korotkoff sounds. With this system, observers can make their measurements via the visual auscultation method, that is to say, by watching those waveforms, instead of the sphygmomanometer, while listening for synchronized Korotkoff sounds. The system was validated according to the International Protocol (IP)., Results: The result showed that all the differences between system measurements by the visual auscultation method and observer measurements by the conventional auscultatory method were within 4 mm Hg., Conclusions: The visual auscultation method achieved a high degree of accuracy, and human observers can be replaced by the system in the validation study of blood pressure measuring devices.

Progress in using information technology to achieve the goal of high-quality health care is hindered by the lack of coordinated data standards. To accelerate quality improvement in pediatrics, child health providers must participate actively in the creation of health care data standards. To do so will require far greater understanding on the part of pediatricians and other pediatric providers regarding the scope and role of data standards in advancing health information systems for children, as well as how data standards could improve quality in child health, what kinds of data standards hold the most promise for quality improvement in child health, and how child health professionals can engage in the work of creating data standards. Child health professionals in organized and academic medicine should participate in standards development organizations, to present the pediatric point of view as data standards emerge. They also should support efforts to certify electronic health record systems that include pediatric functionality. A major challenge to academic pediatrics is to prove that data standards can lead to improved health outcomes for children; this is only a compelling conjecture as of this writing.

Background: A sudden failure of implantable pulse generators (IPG) occurred in 15 out of 143 units during the last 4 years in our patients. This corresponds to a failure rate of 10.5%. In all cases, the connection between the causes of battery and electronic circuit was found defective in the destructive analysis. In order to better understand the failure causes we proceeded to an analysis of explanted IPGs which had reached their normal life span due to depletion of the battery., Method: A functional test and an intensive destructive analysis were carried out in 14 units. The internal parts of the IPG were inspected by light and electron microscopy., Findings: Deformations of the connection between battery and electronic circuit could be found in 12 out of 14 IPGs. The epoxy bonds, which achieve the mechanical fixation between the two contact areas of the bond wires, were found separated in 86%. Additionally, in six out of 14 devices the bond wires were either found lifted or with cracks as a sign of material fatigue., Conclusion: Based on these results we conclude that the IPGs of the affected series did have a technical weak spot. We presume that this issue appears systematically and not randomly or triggered by an unusual action of the patient.

Background: Many patients receive health care in different settings. Thus, a limitation of clinical care may be inaccurate medication lists, since data exchange between settings is often lacking and patients do not regularly self-report on changes in their medication. Health care professionals and patients are both interested in utilizing electronic health information. However, opinion is divided as to who should take responsibility for maintaining personal health records. In Sweden, the government has passed a law to enforce and fund a national register of dispensed medications. The register comprises all individuals with dispensed medications (6.4 million individuals, September 2006) and can be accessed by the individual online via "My dispensed medications". The individual has the right to restrict the accessibility of the information in health care settings., Objective: The aim of the present study was to evaluate the users' attitudes towards their access to "My dispensed medications" as part of a new interactive Internet service on prescribed medications., Method: A password-protected Web survey was conducted among a first group of users of "My dispensed medications". Data was anonymously collected and analyzed with regard to the usefulness and design of the Web site, the respondents' willingness to discuss their "My dispensed medications" with others, their reasons for access, and their source of information about the service., Results: During the study period (January-March, 2007), all 7860 unique site visitors were invited to answer the survey. Invitations were accepted by 2663 individuals, and 1716 responded to the online survey yielding a view rate of 21.8% (1716/7860) and a completion rate of 64.4% (1716/2663). The completeness rate for each question was in the range of 94.9% (1629/1716) to 99.5% (1707/1716). In general, the respondents' expectations of the usefulness of "My dispensed medications" were high (total median grade 5; Inter Quartile Range [IQR] 3, on a scale 1-6). They were also positive about the design of the Web site (total median grade 5; IQR 1, on a scale 1-6). The high grades were not dependent on age or number of drugs. A majority of the respondents, 60.4% (1037/1716), had learned about "My dispensed medications" from pharmacies. 70.4% (1208/1716) of all respondents said they visited "My dispensed medications" to get control or an overview of their drugs. Getting control was a more common (P < .001) answer for the elderly (age 75 or above), whereas curiosity was more common (P < .001) for the younger age group (18-44 years)., Conclusion: We found that users of the provider-based personal medication record "My dispensed medications" appreciated the access to their record. Since we found that the respondents liked the design of the Web site and perceived that the information was easy to understand, the study provided no reason for system changes. However, a need for more information about the register, and to extend its use, was recognized.

Background: Internet survey modalities often compare unfavorably with traditional survey modalities, particularly with respect to response rates. Response to Internet surveys can be affected by the distribution options and response/collection features employed as well as the existence of automated (out-of-office) replies, automated forwarding, server rejection, and organizational or personal spam filters. However, Internet surveys also provide unparalleled opportunities to track study subjects and examine many of the factors influencing the determination of response rates. Tracking data available for Internet surveys provide detailed information and immediate feedback on a significant component of response that other survey modalities cannot match. This paper presents a response audit of a large Internet survey of more than 5000 cancer care providers and administrators in Ontario, Canada., Objective: Building upon the CHEcklist for Reporting Results of Internet E-Surveys (CHERRIES), the main objectives of the paper are to (a) assess the impact of a range of factors on the determination of response rates for Internet surveys and (b) recommend steps for improving published descriptions of Internet survey methods., Methods: We audited the survey response data, analyzing the factors that affected the numerator and denominator in the ultimate determination of response. We also conducted a sensitivity analysis to account for the inherent uncertainty associated with the impact of some of the factors on the response rates., Results: The survey was initially sent out to 5636 health care providers and administrators. The determination of the numerator was influenced by duplicate/unattached responses and response completeness. The numerator varied from a maximum of 2031 crude (unadjusted) responses to 1849 unique views, 1769 participants, and 1616 complete responses. The determination of the denominator was influenced by forwarding of the invitation email to unknown individuals, server rejections, automated replies, spam filters, and 'opt out' options. Based on these factors, the denominator varied from a minimum of 5106 to a maximum of 5922. Considering the different assumptions for the numerator and the denominator, the sensitivity analysis resulted in a 12.5% variation in the response rate (from minimum of 27.3% to maximum of 39.8%) with a best estimate of 32.8%., Conclusions: Depending on how the numerator and denominator are chosen, the resulting response rates can vary widely. The CHERRIES statement was an important advance in identifying key characteristics of Internet surveys that can influence response rates. This response audit suggests the need to further clarify some of these factors when reporting on Internet surveys for health care providers and administrators, particularly when using commercially available Internet survey packages for specified, rather than convenience, samples.

Electrical auditory brainstem responses (E-ABRs) of subjects with cochlear implants are used for monitoring the physiologic responses of early signal processing of the auditory system. Additionally, E-ABR measurements allow the diagnosis of retro-cochlear diseases. Therefore, E-ABR should be available in every cochlear implant center as a diagnostic tool. In this paper, we introduce a low-cost setup designed to perform an E-ABR as well as a conventional ABR for research purposes. The distributable form was developed with Matlab and the Matlab Compiler (The Mathworks Inc.). For the ABR, only a PC with a soundcard, conventional system headphones, and an EEG pre-amplifier are necessary; for E-ABR, in addition, an interface to the cochlea implant is required. For our purposes, we implemented an interface for the Combi 40+/Pulsar implant (MED-EL, Innsbruck).

Background: An automated sphygmomanometer, the BpTRU, was used in a blood pressure (BP) survey of 2,551 residents in the province of Ontario. Automated BP readings were compared with measurements taken by a mercury sphygmomanometer under standardized conditions in a random 10% sample., Methods: BP was recorded in 238 individuals in random order using both a standard mercury device and an automated BP recorder, the BpTRU. All subjects rested for 5 min prior to the first BP reading, which was then discarded. The mean of the next three readings was obtained using the mercury device whereas the BpTRU was set to record a mean of five readings taken at 1 min intervals with subjects resting alone in a quiet room., Results: The mean s.d. BP with the automated device was 115 +/- 16/71 +/- 10 mm Hg compared to 118 +/- 16/74 +/- 10 mm Hg for the manual BP (P < 0.001). A systolic BP > or = 140 mm Hg was present for 16 automated and 19 manual readings. Similarly, the diastolic BP was > or = 90 mm Hg for 9 automated and 14 manual readings. Linear regression analysis showed that automated BP was a significant (P < 0.001) predictor of both manual systolic and diastolic BP., Conclusion: Conventional manual BP readings can be replaced by readings taken using a validated, automated BP recorder in population surveys. The slightly lower readings obtained with the BpTRU device (in the context of reduced observer-subject interaction) may be a more accurate estimate of BP status.

Operant animal behavioral tests require the interaction of the subject with sensors and actuators distributed in the experimental environment of the arena. In order to provide user independent reliable results and versatile control of these devices it is vital to use an automated control system. Commercial systems for control of animal mazes are usually based in software implementations that restrict their application to the proprietary hardware of the vendor. In this paper we present OpenControl: an opensource Visual Basic software that permits a Windows-based computer to function as a system to run fully automated behavioral experiments. OpenControl integrates video-tracking of the animal, definition of zones from the video signal for real-time assignment of animal position in the maze, control of the maze actuators from either hardware sensors or from the online video tracking, and recording of experimental data. Bidirectional communication with the maze hardware is achieved through the parallel-port interface, without the need for expensive AD-DA cards, while video tracking is attained using an inexpensive Firewire digital camera. OpenControl Visual Basic code is structurally general and versatile allowing it to be easily modified or extended to fulfill specific experimental protocols and custom hardware configurations. The Visual Basic environment was chosen in order to allow experimenters to easily adapt the code and expand it at their own needs.

The design of a removable miniature microdrive-headstage waterproof assembly for extracellular recordings of single unit activity with high-impedance electrodes in swimming mice is presented. The assembly provides perfect protection of the critical components and electric contacts from water. Neuronal activity may be recorded even if the animal is diving and swimming under the water surface. The advantages of this construction include simple installation and removal of the electrodes, rapid attachment of the assembly to the animal's skull, and rapid removal after recording. The device provides precise vertical positioning of the electrode without rotation or lateral shift, stable recordings of single units for several hours and the possibility to change the penetration track many times in the same animal. The assembly weight is less than 160mg. This work is the first successful attempt to record neuronal activity in mice performing spatial task in water maze.

A large scale neural network simulation with realistic cortical architecture has been undertaken to investigate the effects of external electrical stimulation on the propagation and evolution of ongoing seizure activity. This is an effort to explore the parameter space of stimulation variables to uncover promising avenues of research for this therapeutic modality. The model consists of an approximately 800 mum x 800 mum region of simulated cortex, and includes seven neuron classes organized by cortical layer, inhibitory or excitatory properties, and electrophysiological characteristics. The cell dynamics are governed by a modified version of the Hodgkin-Huxley equations in single compartment format. Axonal connections are patterned after histological data and published models of local cortical wiring. Stimulation induced action potentials take place at the axon initial segments, according to threshold requirements on the applied electric field distribution. Stimulation induced action potentials in horizontal axonal branches are also separately simulated. The calculations are performed on a 16 node distributed 32-bit processor system. Clear differences in seizure evolution are presented for stimulated versus the undisturbed rhythmic activity. Data is provided for frequency dependent stimulation effects demonstrating a plateau effect of stimulation efficacy as the applied frequency is increased from 60 to 200 Hz. Timing of the stimulation with respect to the underlying rhythmic activity demonstrates a phase dependent sensitivity. Electrode height and position effects are also presented. Using a dipole stimulation electrode arrangement, clear orientation effects of the dipole with respect to the model connectivity is also demonstrated. A sensitivity analysis of these results as a function of the stimulation threshold is also provided.

Background: There is evidence that blood pressure measurement outside the doctor's office can provide valuable information for the diagnostic evaluation of hypertensive patients and for monitoring their response to treatment. Home blood pressure monitoring devices have a major role in this setting, provided that their accuracy in measuring blood pressure is demonstrated by validation studies., Objective: This study aimed at verifying whether the automatic electronic oscillometric blood pressure measuring device Artsana CSI 610 complied with the standard of accuracy indicated by the ESH International Protocol., Methods: Sequential measurements of systolic and diastolic blood pressure were obtained in 33 participants using the mercury sphygmomanometer (two observers) and the test device (one supervisor). A standard adult cuff was always employed during the study. According to the ESH validation protocol, 99 couples of test device and reference blood pressure measurements were obtained during the two phases of the study (three pairs for each of the 33 participants)., Results: The Artsana CSI 610 device successfully passed phase 1 of study validation with the number of absolute differences between test and reference device never <35 within 5 mmHg and never <40 within 10 and 15 mmHg. The test device also passed phase 2 of the validation study with a mean (+/-SD) device-observer difference of -1.4+/-4.8 mmHg for systolic and -0.9+/-3.5 mmHg for diastolic blood pressure., Conclusions: According to the results of the validation study on the basis of the ESH International Protocol, the Artsana CSI 610 can be recommended for clinical use in adults.

We propose an easy-to-construct digital video editing system ideal to produce video documentation and still images. A digital video editing system applicable to many video sources in the operating room is described in detail. The proposed system has proved easy to use and permits one to obtain videography quickly and easily. Mixing different streams of video input from all the devices in use in the operating room, the application of filters and effects produces a final, professional end-product. Recording on a DVD provides an inexpensive, portable and easy-to-use medium to store or re-edit or tape at a later time. From stored videography it is easy to extract high-quality, still images useful for teaching, presentations and publications. In conclusion digital videography and still photography can easily be recorded by the proposed system, producing high-quality video recording. The use of firewire ports provides good compatibility with next-generation hardware and software. The high standard of quality makes the proposed system one of the lowest priced products available today.

Medical devices driven by electric power have come to be commonly used in hospitals, and rapid changes of voltage or current can easily cause them to fail. A stable and high quality power supply is indispensable in order to maintain safety in the modern clinical setting. Therefore, we investigated the quality of the power supply in a hospital and determined the tolerance of 13 pieces of medical equipment to voltage dips. The results showed little distortion of the voltage wave. However, we found an approximately 7% momentary voltage dip caused by lightening and other problems, such as 2 to 5% periodic drops in voltage and voltage wave distortions caused by incorrect grounding. In a tolerance test, the settings of some medical devices were changed at the time of automatic reboot after a disturbance. For another device, trend information was initialized.

Researchers examined hot and cold beverage consumption, tachypnea, and bradypnea effects on oral electronic thermometer readings. Results indicate that waiting at least 30 minutes after drinking yields a more accurate reading. Outcomes also suggest that bradypnea may create false temperature elevations.

Objective: To evaluate an electronic diary as a tool to evaluate the occurrence and relationship of headaches and premenstrual syndrome (PMS) symptoms throughout the menstrual cycle in women with migraine., Background: Menstrually related headache and PMS significantly impact the quality of life of many women. The time relationship of these 2 menstrually related problems is not well understood and not well described., Methods: Twenty women with migraine experiencing regular menstrual cycles were enrolled in a prospective study designed to date- and time-stamp data, both self- and computer-prompted, headache and PMS symptoms, for 3 consecutive months. A previously validated PMS score was calculated by grading 23 PMS criteria on a scale of 0 to 3 (0 = no symptoms, 3 = severe symptoms)., Results: The total number of data entries recorded was 2009, composed of 56 menstrual cycles in 20 migraineurs. Five hundred forty-four entries reported a current, prodromal, or previous headache. The mean daily occurrence of headache increased beginning on cycle day -5, peaked on days +1 to +5, and returned to baseline by day +7. Mean daily PMS scores ranged from 2.4 to 12. Mean daily PMS scores peaked on days -6 to +2 and returned to baseline by day +8., Conclusions: An electronic diary may have potential as a diagnostic tool in studying headaches and PMS symptoms throughout the menstrual cycle. The occurrence of headache and PMS symptoms in migraineurs follows similar time courses.

Background: Acute intestinal edema adversely affects intestinal transit, permeability, and contractility. Current resuscitation modalities, while effective, are associated with development of acute intestinal edema. Knowledge of levels of tissue edema would allow clinicians to monitor intestinal tissue water and may help prevent the detrimental effects of edema. However, there is no simple method to measure intestinal tissue water without biopsy. We sought to develop a tissue impedance analyzer to measure tissue edema, without the need for invasive biopsy., Methods: Oscillating voltage input was applied to the analyzer circuit and an oscilloscope measured the voltage output across any load. Rats were randomized to three groups: sham, mild edema (80 mL/kg of NS resuscitation), and severe edema (80 mL/kg of NS resuscitation with intestinal venous hypertension). Intestinal edema was measured by wet-to-dry tissue weight ratio. Bowel impedance was measured and converted to capacitance using a standard curve., Results: Acute intestinal edema causes a significant increase in bowel capacitance. This capacitance can be used to predict tissue water concentration., Conclusion: Using an impedance analyzer circuit, it is possible to measure intestinal edema reliably and quickly. This may prove to be a useful tool in the resuscitation of critically ill patients.

Nerve stimulation is considered by many to be the current 'gold standard' for locating peripheral nerves. Thirteen nerve stimulators were subjected to a battery of tests performed by two independent observers under standardised conditions using a digital oscilloscope, a calibrated resistance and a novel scoring system. Individual scores were assigned for the signal waveform, current intensity, impulse duration, maximum load output and functionality of each nerve stimulator; the maximum score achievable was 20. A score of > or = 15/20 was achieved by six nerve stimulators: Stimuplex HNS 12 (B Braun); MultiStim Vario (Pajunk); Plexival (Medival, Vygon); MultiStim Sensor (Pajunk); Plexygon (Aryon, Vygon); Stimuplex HNS 11 (B Braun). Seven nerve stimulators scored < 15/20. Anaesthetists should be aware of the limitations of the nerve stimulator being used. Standardisation of features is desirable when manufacturing nerve stimulators.

Field testing of medical electrical equipment remains a topic of debate amongst biomedical engineers. A questionnaire was circulated among members of the main professional body for Medical Engineering Departments in the UK and Ireland and in the Medical Physics and Engineering Mailbase Server. The aim of the questionnaire was to establish consensus on common practice on the frequency and type of safety tests carried out in the field and common sources of hazards and risk management. Twenty-six replies were received in total. A clear majority of 54% of the respondents reported that they carried out safety tests on hospital-based medical equipment on a yearly basis. For other equipment, regular tests were carried out by 58% on loan equipment and by 69% on medical electrical systems. Laboratory equipment on the other hand were not tested in 42% of the cases. Domiciliary and research equipment were only tested in 11% and 15% of the cases respectively. A clear majority of 93% said that they label equipment after tests, 34% said that they always record the actual values (as opposed to pass or fail) and 54% said they carry out functional test as part of the safety test. Although 61% of failures were attributed to the mains lead, only 50% of the respondents said that they had a management system in place for detachable mains leads.

Due to the wide variety of equipment existing in clinical areas, there is an important question: which and how often electrical safety tests most be applied to the medical equipment. There are important differences about the electrical safety, such as the electrical insulation or the hazard considering the connection between patient and electrical instrumentation. The objective of this work was to develop an Electrical Safety Priority Index for Medical Equipment(ESPIME) involving different classifications related with electrical safety, in order to provide a numeric code indicating the priority and frequency for applying the electrical safety tests to medical equipment. The index were applied to the medical equipment in critical care locations and the result,were used to defined which set of medical equipment would be the first for developing and applying electrical safety tests in a private hospital in Mexico City.

Commercial photodynamic therapy (PDT) light sources are supplied with no evidence of traceability to national measurements standards to validate indicated delivered dose. Also, the spatial distribution of the radiant energy is not disclosed. This means that there is no way for the user to be able to verify that the required dose is being delivered to the appropriate area of the lesion. To this end, a simple method, traceable to national standards, is described and applied to an investigation of two commercial LED arrays. In one case, the dose fell to 38% of that received at the central area at a distance of only 2 cm. In the other, the output was more uniform over a larger area but the maximum irradiance was not at the centre of the field. All of these inhomogenieties were taken into account when the actual light dose delivered to the patient was calculated in the method described. This ensured transparent traceability in PDT dosimetry.

The Food and Drug Administration (FDA) is issuing a final rule to amend the Federal performance standard for diagnostic x-ray systems and their major components (the performance standard). The agency is taking this action to update the performance standard to account for changes in technology and use of radiographic and fluoroscopic x-ray systems and to fully utilize the International System of Units to describe radiation-related quantities and their units when used in the performance standard. For clarity and ease of understanding, FDA is republishing the complete contents, as amended, of three sections of the performance standard regulations and is amending a fourth section without republishing it in its entirety. This action is being taken under the Federal Food, Drug, and Cosmetic Act (the act), as amended by the Safe Medical Devices Act of 1990 (SMDA).

We developed and evaluated an intra-oral electrolaryngeal speech aid system for those who could not acquire common alaryngeal speech or for early post-surgery speech rehabilitation. Our system consisted of a denture-base intra-oral vibrator, a wireless miniature fingertip switch and a controller. To produce natural speech, the fingertip switch produced binary commands of voicing and accent and the controller implemented the pitch generation model using the commands. We first estimated the intelligibility of consonant-vowel syllables produced by our system. We then obtained the feedback about the system from the Japanese users on the basis of their daily life use, and evaluated the possibility and acceptability as an alaryngeal speech aid. Although the users were less satisfied at the intra-oral electrolarynx, the intelligibility of the intra-oral electrolarygeal speech was comparable to that of transcervical electrolaryngeal speech, and most of them were willing to employ it if they lost their current electrolaryngeal speech. According to the feedbacks from the users, a completely wire-free system and less eye-catching designs would make the prosthesis more acceptable. These results placed the intra-oral electrolarynx as a useful option of alaryngeal speech aids and encouraged the further development of the intra-oral electrolarynx.

This essay explains several essential concepts which are closely related to the safety of medical electrical systems. It expounds the key problems of building up medical electrical systems based on safety requirements, and performing compliance tests. Therefore,it is of realistic significance when carrying out GB9706.15.

Purpose: To create a data management system that: (1) standardizes antecedent, program, and outcome variables relevant to the shared goals of adolescent-oriented maternity programs while allowing users to add variables pertaining to unique aspects of their work; (2) cues providers to physiologic and psychosocial characteristics that predispose teenagers to adverse pregnancy and parenting outcomes, (3) standardizes patient care by guiding providers through adolescent-oriented prenatal, postpartum, and well baby visits, and (4) establishes the infrastructure to collect data from a nationally representative sample of pregnant and parenting teens., Method: We adapted a powerful, state-of-the-art relational database framework (Microsoft Access 2000) to create an easy-to-use data management system-The Electronic Report on Adolescent Pregnancy (ERAP)-that requires minimal training to use on a personal computer., Results: ERAP is designed to meet the administrative and analytic needs of adolescent-oriented maternity programs. It consists of six linked core data tables (teen, pregnancy, prenatal visits, child, interconception interval, and interconception interval visits), that allow users to analyze data from these multiple views while preserving the family structure. In addition, the database standardizes methods for collecting and storing the information and automatically computing the variables needed to monitor and evaluate an adolescent-oriented maternity program. Since by adding variables and appending supplementary tables, users can modify the core database to accommodate unique aspects of their programs and/or research, ERAP is also an ideal conduit for translating research findings into clinical practice. Similarly, because ERAP actually structures the care patients receive, the database provides the infrastructure needed to develop and implement best practice guidelines for treating teen-headed families. Finally, the confidentiality of all subject data is assured because ERAP is password-protected and automatically prepares files for batched external analyses by removing personal identifiers., Conclusions: ERAP provides the infrastructure needed to create a teen-pregnancy databank at the national level and an efficient patient monitoring system at the program level. By standardizing variable definitions and data collection techniques, serving as a repository for data collected at multiple sites, and tracking the multidisciplinary aspects of the care patients receive, ERAP has the potential to facilitate collaboration between adolescent-oriented maternity programs, increase the scientific rigor of teen pregnancy research, and improve the quality of care individual teen-headed families receive by prompting compliance with best practice guidelines.

The ability of electronic drug identification databases to identify solid oral dosage forms by their imprint codes was studied. The following seven commercially available electronic drug identification databases were selected to identify 500 solid oral dosage forms by their imprint codes: Clinical Pharmacology (Gold Standard Media, Tampa, FL), eFacts (Facts and Comparison, St. Louis, MO), Ident-A-Drug (Therapeutic Research, Stockton, CA), Identidex (Micromedex, Greenwood Village, CO), Clinical Reference Library (Lexi-Comp, Hudson, OH), Physicians' Desk Reference (PDR) Electronic Library (Medical Economics, Montvale, NJ), and RxList (RxList LLC, San Francisco, CA), Chi-square test was used to compare the percentages of medications identified by each of the seven electronic references. The ability of the databases to identify medication by specific characteristics, such as brand name versus generic, prescription versus nonprescription, commercially available for more than one year versus less than one year, colored versus white drug products, and controlled versus noncontrolled substances was evaluated. A logistic regression model was used to determine the probability of a drug product being identified by one of the electronic references based on these characteristics. All seven electronic databases combined identified 95.6% of the unknown medications by imprint code, color, shape, and scoring. Ident-A-Drug and Identidex identified the most drugs. The PDR Electronic Library and Facts and Comparisons Identified the least number of drugs. Solid oral dosage forms more likely to be identified were those that were on the market for more than a year, brand-name products, and prescription medications. Generic products on the market for less than a year and nonprescription products were particularly difficult to identify. A combination of electronic drug identification databases provides the best method of drug identification in an institutional setting.

The research was carried out on the upper permanent incisor teeth of 101 children aged 8-12 years attending the trauma clinic at the University Dental Hospital, Manchester, UK. The double blind, cross-over study involved Periotest readings being taken by one examiner and traditional special tests being carried out by another examiner. The traditional special tests chosen were mobility testing, percussion sounds and radiographs. The Periotest readings and special tests were then repeated at the child's recall appointment. The results revealed that there was a significant difference (P < 0.001) between the number of abnormalities detected by the Periotest and those detected by the traditional special tests. There was also found to be a significant difference (P < 0.001) in the detection of undesirable sequelae between the Periotest and the traditional special tests.

The Periotest is a non-invasive, electronic device which provides an objective measurement of the reaction of the periodontium to a defined impact load applied to the tooth crown. In order for a clinician to interpret Periotest readings, normal physiological values must be known. In traumatology, using the contralateral tooth as a control is impractical, as it too may be affected by injury. The main purpose of this research project was to establish the normal physiological Periotest readings for upper permanent incisor teeth at an age when trauma to teeth is at a peak. This was achieved by taking Periotest readings on healthy upper permanent incisors of 250 children aged between 8-12 years. Test-retest reliability was investigated by taking repeated Periotest readings on the teeth of 13 dental nurses at timed intervals over a 2-h period. The practicality of using the device on children was examined by examiner observation and patient questionnaire. Results showed a wide variation of Periotest readings in healthy upper permanent incisor teeth in 8-12-year-olds, and thus it was felt that normal physiological measurements are best expressed as a range. The test-retest reliability of readings was good (R > 0.85) provided that the repeat reading was taken at least 15 min after the initial reading. The examiner found the equipment easy to use and taking measurement was readily acceptable by the sample group. It was concluded that Periotest could be utilised in traumatology, although the clinician needs to take into account the limitations of the device and the difficulty in interpreting the results.

MLVs are an effective tool for designers to meet next generation EMC requirements for medical devices. FeedThru MLVs give designers a new option for highly efficient ESD suppression because of their improved turn-on time characteristics. In addition, FeedThru MLVs give designers highly selective EMI filters to suppress unwanted frequency emissions or isolate the circuit from the frequency spectrum where susceptibility would be a concern.

We present here the EMInet (Electronic Medical Information network), a closed information network established by the City government and the Medical Association in Matsudo City, Chiba, Japan. In this network, medical information is shared by multiple certified medical facilities under the informed consent of the patients. The medical record is written only by the physician in charge of the patient and reserved in the server computer. The medical record cannot be rewritten or modified by anyone except the physician in charge of the patient. Other medical professionals can only have access to the record. In the emergency room of certified hospitals, a physician can open the patient's record by using the IC card carried by the patient.

The safety of any medical device system is dependent on the application of a disciplined, well-defined, risk management process throughout the product life cycle. Hardware, software, human, and environmental interactions must be assessed in terms of intended use, risk, and cost/benefit criteria. This article addresses these issues in the context of medical devices that incorporate software. The article explains the principles of risk management, using terminology and examples from the domain of software engineering. It may serve as a guide to those new to the concepts of risk management and as an aide-memoire for medical device system/software engineers who are more familiar with the topic.