Evaluation of photography using head-mounted display technology (ICAPS) for district Trachoma surveys

Background

As the prevalence of trachoma declines worldwide, it is becoming increasingly expensive and challenging to standardize graders in the field for surveys to document elimination. Photography of the tarsal conjunctiva and remote interpretation may help alleviate these challenges. The purpose of this study was to develop, and field test an Image Capture and Processing System (ICAPS) to acquire hands-free images of the tarsal conjunctiva for upload to a virtual reading center for remote grading.

Methodology/Principal findings

This observational study was conducted during a district-level prevalence survey for trachomatous inflammation—follicular (TF) in Chamwino, Tanzania. The ICAPS was developed using a Samsung Galaxy S8 smartphone, a Samsung Gear VR headset, a foot pedal trigger and customized software allowing for hands-free photography. After a one-day training course, three trachoma graders used the ICAPS to collect images from 1305 children ages 1–9 years, which were expert-graded remotely for comparison with field grades. In our experience, the ICAPS was successful at scanning and assigning barcodes to images, focusing on the everted eyelid with adequate examiner hand visualization, and capturing images with sufficient detail to grade TF. The percentage of children with TF by photos and by field grade was 5%. Agreement between grading of the images compared to the field grades at the child level was kappa = 0.53 (95%CI = 0.40–0.66). There were ungradable images for at least one eye in 199 children (9.1%), with more occurring in children ages 1–3 (18.5%) than older children ages 4–9 (4.2%) (χ² = 145.3, p<0.001).

Conclusions/Significance

The prototype ICAPS device was robust, able to image 1305 children in a district level survey and transmit images from rural Tanzania to an online grading platform. More work is needed to improve the percentage of ungradable images and to better understand the causes of disagreement between field and photo grading.

Trachoma is the leading infectious cause of blindness worldwide, caused by the bacterium Chlamydia trachomatis. Programs targeting trachoma elimination in endemic regions largely rely on periodic prevalence surveys to monitor progress, but training field graders requires active cases, which is becoming challenging as prevalence declines. Photography of the tarsal conjunctiva with remote interpretation via telemedicine may serve as a more auditable, effective, and cost-efficient method for surveys. We developed and evaluated the Image Capture and Processing System (ICAPS), a smartphone-based, hands-free, head-mounted camera system (Samsung Galaxy S8 with custom app, Samsung Gear VR headset, and a Bluetooth-linked foot pedal trigger). The ICAPS was easy to use in challenging field conditions, was able to upload images from Tanzania and link images to field data. The percentage of TF was 5% by both field grade and photo grade, with agreement kappa = 0.53. Additional field training and enhanced certification of photographers may help reduce the proportion of ungradable images; further research on reasons for mismatch of grades between field and photo is needed.

Small-volume detection: platform developments for clinically-relevant applications

Biochemical analysis of human body fluids is a frequent and fruitful strategy for disease diagnosis. Point-of-care (POC) diagnostics offers the tantalizing possibility of providing rapid diagnostic results in non-laboratory settings. Successful diagnostic testing using body fluids has been reported on in the literature; however, small-volume detection devices, which offer remarkable advantages such as portability, inexpensiveness, capacity for mass production, and tiny sample volume requirements have not been thoroughly discussed. Here, we review progress in this research field, with a focus on developments since 2015. In this review article, we provide a summary of articles that have detailed the development of small-volume detection strategies using clinical samples over the course of the last 5 years. Topics covered include small-volume detection strategies in ophthalmology, dermatology or plastic surgery, otolaryngology, and cerebrospinal fluid analysis. In ophthalmology, advances in technology could be applied to examine tear or anterior chamber (AC) fluid for glucose, lactoferrin, interferon, or VEGF. These approaches could impact detection and care for diseases including diabetic mellitus, dry-eye disease, and age-related maculopathy. Early detection and easy monitoring are critical approaches for improving overall care and outcome. In dermatology or plastic surgery, small-volume detection strategies have been applied for passive or interactive wound dressing, wound healing monitoring, and blister fluid analysis for autoimmune disease diagnosis. In otolaryngology, the analysis of nasal secretions and mucosa could be used to differentiate between allergic responses and infectious diseases. Cerebrospinal fluid analysis could be applied in neurodegenerative diseases, central neural system infection and tumor diagnosis. Other small-volume fluids that have been analyzed for diagnostic and monitoring purposes include semen and cervico-vaginal fluids. We include more details regarding each of these fluids, associated collection and detection devices, and approaches in our review.

Improving diagnostic specimen management systems in an oral medicine department

Histological, haematological and microbiological investigations are essential in the field of oral medicine and are a crucial adjunct to clinical findings, often being relied on to obtain a definitive diagnosis. Importantly, in some cases, these investigations can help exclude or confirm the presence of malignancy. This project highlighted some problems regarding labelling and recording of specimens in an oral medicine department and a lack of clear specimen management processes. It aimed to improve specimen management by reducing reported incidents surrounding diagnostic tests. Quality improvement methods such as process mapping were key to understanding the journey of specimens and the departments involved at each stage of the system. Initiatives included a recording log book, staff training, information signage around the clinic and delegation of responsibilities, all of which were implemented over multiple plan, do, study, act (PDSA) cycles. The project was extremely successful and since implementation there has been a clear and sustained reduction in reported incidents. The small number of incidents which did occur all involved transportation of specimens and none involved labelling or recording. One can conclude that the change in test management systems in terms of recording and labelling of specimens in the department has been sustained. Ongoing engagement with stakeholders and senior leaders is the priority to ensure further reduction in incidents in the future and that the improvements are maintained. This project demonstrates how simple, realistic, cost-effective, quality improvement initiatives can have a significant positive impact on patient care and hospital management systems.

Challenges for Microelectronics in Non-Invasive Medical Diagnostics

Microelectronics is emerging, sometimes with changing fortunes, as a key enabling technology in diagnostics. This paper reviews some recent results and technical challenges which still need to be addressed in terms of the design of CMOS analog application specific integrated circuits (ASICs) and their integration in the surrounding systems, in order to consolidate this technological paradigm. Open issues are discussed from two, apparently distant but complementary, points of view: micro-analytical devices, combining microfluidics with affinity bio-sensing, and gamma cameras for simultaneous multi-modal imaging, namely scintigraphy and magnetic resonance imaging (MRI). The role of integrated circuits is central in both application domains. In portable analytical platforms, ASICs offer miniaturization and tackle the noise/power dissipation trade-off. The integration of CMOS chips with microfluidics poses multiple open technological issues. In multi-modal imaging, now that the compatibility of the acquisition chains (thousands of Silicon Photo-Multipliers channels) of gamma detectors with Tesla-level magnetic fields has been demonstrated, other development directions, enabled by microelectronics, can be envisioned in particular for single-photon emission tomography (SPECT): a faster and simplified operation, for instance, to allow transportable applications (bed-side) and hardware pre-processing that reduces the number of output signals and the image reconstruction time.

Recent Advances in Cellulose-Based Biosensors for Medical Diagnosis

Cellulose has attracted much interest, particularly in medical applications such as advanced biosensing devices. Cellulose could provide biosensors with enhanced biocompatibility, biodegradability and non-toxicity, which could be useful for biosensors. Thus, they play a significant role in environmental monitoring, medical diagnostic tools, forensic science, and foodstuff processing safety applications. This review summarizes the recent developments in cellulose-based biosensors targeting the molecular design principles toward medical detection purposes. The recognition/detection mechanisms of cellulose-based biosensors demonstrate two major classes of measurable signal generation, including optical and electrochemical cellulosic biosensors. As a result of their simplicity, high sensitivity, and low cost, cellulose-based optical biosensors are particularly of great interest for including label-free and label-driven (fluorescent and colorimetric) biosensors. There have been numerous types of cellulose substrates employed in biosensors, including several cellulose derivatives, nano-cellulose, bacterial cellulose, paper, gauzes, and hydrogels. These kinds of cellulose-based biosensors were discussed according to their preparation procedures and detection principle. Cellulose and its derivatives with their distinctive chemical structure have demonstrated to be versatile materials, affording a high-quality platform for accomplishing the immobilization process of biologically active molecules into biosensors. Cellulose-based biosensors exhibit a variety of desirable characteristics, such as sensitivity, accuracy, convenience, quick response, and low-cost. For instance, cellulose paper-based biosensors are characterized as being low-cost and easy to operate, while nano-cellulose biosensors are characterized as having a good dispersion, high absorbance capacity, and large surface area. Cellulose and its derivatives have been promising materials in biosensors which could be employed to monitor various bio-molecules, such as urea, glucose, cell, amino acid, protein, lactate, hydroquinone, gene, and cholesterol. The future interest will focus on the design and construction of multifunctional, miniaturized, low-cost, environmentally friendly, and integrated biosensors. Thus, the production of cellulose-based biosensors is very important.

A Novel Method to Estimate the Full Knee Joint Kinematics Using Low Cost IMU Sensors for Easy to Implement Low Cost Diagnostics

Traditional motion capture systems are the current standard in the assessment of knee joint kinematics. These systems are, however, very costly, complex to handle, and, in some conditions, fail to estimate the varus/valgus and internal/external rotation accurately due to the camera setup. This paper presents a novel and comprehensive method to infer the full relative motion of the knee joint, including the flexion/extension, varus/valgus, and internal/external rotation, using only low cost inertial measurement units (IMU) connected to the upper and lower leg. Furthermore, sensors can be placed arbitrarily and only require a short calibration, making it an easy-to-use and portable clinical analysis tool. The presented method yields both adequate results and displays the uncertainty band on those results to the user. The proposed method is based on an fixed interval smoother relying on a simple dynamic model of the legs and judicially chosen constraints to estimate the rigid body motion of the leg segments in a world reference frame. In this pilot study, benchmarking of the method on a calibrated robotic manipulator, serving as leg analogue, and comparison with camera-based techniques confirm the method’s accurateness as an easy-to-implement, low-cost clinical tool.

Ultrahigh-Sensitivity Sandwiched Plasmon Ruler for Label-Free Clinical Diagnosis

Optical biosensors, especially those based on plasmonic structures, have emerged recently as a potential tool for disease diagnostics. Plasmonic biosensors have demonstrated impressive benefits for the label-free detection of trace biomarkers in human serum. However, widespread applications of these technologies are hindered because of their insufficient sensitivity, their relatively complex chemical immobilization processes, and the use of prism couplers. Accordingly, a sandwiched plasmon ruler (SW-PR) based on a Au nanohole array with ultrahigh sensitivity arising from the plasmonic coupling effect is developed. Highly confined surface charges caused by Bloch wave surface plasmon polarizations substantially increase the coupling efficiency. This platform exhibits thickness sensitivity as high as 61 nm nm^-1 and can detect at least 200 000-fold lower analyte concentrations than a nanowell sensing platform with the same wavelength shift. Additionally, the sandwiched plasmonic biosensor allows precise and label-free testing of clinical biomarkers, namely C-reactive protein and procalcitonin, in patient serum samples without requiring a sophisticated prism coupler, extra antibodies, or a chemical immobilization technique. This study yields new insight into the structural design of plasmon rulers and will open exciting avenues for disease diagnosis and therapy follow-up at the point-of-care.

Taste test using an edible taste film kit: a randomised controlled trial

OBJECTIVES

We developed an edible taste film test that can be stored easily as a kit. This study was conducted to confirm the agreement between the results of the edible taste film kit test and the conventional taste solution test.

DESIGN

Prospective, randomised, controlled trial.

SETTING

Single tertiary hospital.

PARTICIPANTS

Sixty-two healthy volunteers with no self-described taste problems.

INTERVENTIONS

A randomisation scheme was used to determine the order of use of the edible taste film kit and the taste solution test for each subject. The taste solution test was performed using a cotton swab. In the taste film kit test, an edible taste film was placed on the tongue, and the subject detected the taste after the film was dissolved by saliva.

OUTCOME MEASURES

For each test, we measured the taste identification threshold, taste detection time and total test time.

RESULTS

We confirmed the consistency of the taste identification thresholds of the two tests, and the results were consistent with each other except for the bitter taste results, which used coffee in the edible taste film kit and quinine in the taste solution test. Although the detection time for each taste quality was faster for the taste solution test, the mean total time was significantly shorter for the taste film kit test than for the taste solution test (6.16±2.27 min vs 7.04±1.98 min, respectively; p=0.004).

CONCLUSIONS

The edible taste film kit along with the taste solution test will be useful for quantitative taste testing.

TRIAL REGISTRATION NUMBER

KCT0002865.

Disposable Sensors in Diagnostics, Food, and Environmental Monitoring

Disposable sensors are low-cost and easy-to-use sensing devices intended for short-term or rapid single-point measurements. The growing demand for fast, accessible, and reliable information in a vastly connected world makes disposable sensors increasingly important. The areas of application for such devices are numerous, ranging from pharmaceutical, agricultural, environmental, forensic, and food sciences to wearables and clinical diagnostics, especially in resource-limited settings. The capabilities of disposable sensors can extend beyond measuring traditional physical quantities (for example, temperature or pressure); they can provide critical chemical and biological information (chemo- and biosensors) that can be digitized and made available to users and centralized/decentralized facilities for data storage, remotely. These features could pave the way for new classes of low-cost systems for health, food, and environmental monitoring that can democratize sensing across the globe. Here, a brief insight into the materials and basics of sensors (methods of transduction, molecular recognition, and amplification) is provided followed by a comprehensive and critical overview of the disposable sensors currently used for medical diagnostics, food, and environmental analysis. Finally, views on how the field of disposable sensing devices will continue its evolution are discussed, including the future trends, challenges, and opportunities.

Rapid screening of engineered microbial therapies in a 3D multicellular model

Synthetic biology is transforming therapeutic paradigms by engineering living cells and microbes to intelligently sense and respond to diseases including inflammation, infections, metabolic disorders, and cancer. However, the ability to rapidly engineer new therapies far outpaces the throughput of animal-based testing regimes, creating a major bottleneck for clinical translation. In vitro approaches to address this challenge have been limited in scalability and broad applicability. Here, we present a bacteria-in-spheroid coculture (BSCC) platform that simultaneously tests host species, therapeutic payloads, and synthetic gene circuits of engineered bacteria within multicellular spheroids over a timescale of weeks. Long-term monitoring of bacterial dynamics and disease progression enables quantitative comparison of critical therapeutic parameters such as efficacy and biocontainment. Specifically, we screen Salmonella typhimurium strains expressing and delivering a library of antitumor therapeutic molecules via several synthetic gene circuits. We identify candidates exhibiting significant tumor reduction and demonstrate high similarity in their efficacies, using a syngeneic mouse model. Last, we show that our platform can be expanded to dynamically profile diverse microbial species including Listeria monocytogenes, Proteus mirabilis, and Escherichia coli in various host cell types. This high-throughput framework may serve to accelerate synthetic biology for clinical applications and for understanding the host-microbe interactions in disease sites.

The Effect of Medical Technology Innovations on Patient Outcomes, 1990-2015: Results of a Physician Survey

BACKGROUND

Developments in diagnostics, medical devices, procedures, and prescription drugs have increased life expectancy and quality of life after diagnosis for many diseases. Previous research has shown that, overall, increased investment in medical technology has led to increased health outcomes. In addition, the value of investment in specific innovations, particularly in new pharmaceuticals or biopharmaceuticals, has frequently been shown through an evaluation of the associated health outcomes and costs. Value assessments for all medical technologies and interventions are an important consideration in current debates on access and affordability of health care in the United States.

OBJECTIVE

To identify practicing physician impressions of the historical effect of postdiagnosis innovations in medical technology on patient outcomes within the 8 health conditions that have the largest effect on health in the United States.

METHODS

National statistics were used to identify the 8 conditions responsible for the most mortality and morbidity within the United States between 1990 and 2014. A physician survey was developed for each major condition to obtain physician opinion on the extent to which pharmaceuticals and biopharmaceuticals, medical devices, diagnostics, and surgical procedures contributed to improvements in postdiagnosis mortality and morbidity outcomes over the evaluated period. Respondents were provided with a fifth category, "cannot allocate," to account for postdiagnosis outcome gains resulting from other factors such as public health interventions.

RESULTS

The conditions identified as having the greatest effect on morbidity and mortality since 1990 were breast cancer, ischemic heart disease, human immunodeficiency virus infection, diabetes, unipolar depression, chronic obstructive pulmonary disease, cerebrovascular disease, and lung cancer. After excluding other factors, physicians specializing in these conditions, with a mean of 21.4 years in practice, considered pharmaceuticals and biopharmaceuticals as having the greatest postdiagnosis effect across all 8 conditions, with 56% of outcome gains attributed to this innovation category. Diagnostics was the second biggest contributor at 20%.

CONCLUSIONS

Physician perceptions indicated that attention should be paid to value assessments of innovative diagnostics, devices, and surgical procedures, as well as to pharmaceuticals and biopharmaceuticals, before goals for allocating health care expenditures among the different innovations are determined.

DISCLOSURES

Funding for this study was provided by the National Pharmaceutical Council, a health policy research group that receives its funding from biopharmaceutical manufacturers. Wamble is employed by RTI Health Solutions, which received funding from the National Pharmaceutical Council to conduct this research. Ciarametaro and Dubois are employed by the National Pharmaceutical Council.

The Eye as a Window to Health: Albeit Slow, Research is Progressing on Contact Lenses for Medical Diagnostics

The idea is a compelling one: a device that looks and feels like an ordinary contact lens but that can continuously monitor a variety of health indicators. For a diabetic, such a lens might update blood glucose levels and, using a built-in flashing LED indicator light, signal when a condition needs attention. Diabetic patients might be saved from the need for repeated finger prick tests and could be monitored for longer periods of time and for a greater variety of parameters at once.

Technology-enabled examinations of cardiac rhythm, optic nerve, oral health, tympanic membrane, gait and coordination evaluated jointly with routine health screenings: an observational study at the 2015 Kumbh Mela in India

OBJECTIVES

Technology-enabled non-invasive diagnostic screening (TES) using smartphones and other point-of-care medical devices was evaluated in conjunction with conventional routine health screenings for the primary care screening of patients.

DESIGN

Dental conditions, cardiac ECG arrhythmias, tympanic membrane disorders, blood oxygenation levels, optic nerve disorders and neurological fitness were evaluated using FDA-approved advanced smartphone powered technologies. Routine health screenings were also conducted. A novel remote web platform was developed to allow expert physicians to examine TES data and compare efficacy with routine health screenings.

SETTING

The study was conducted at a primary care centre during the 2015 Kumbh Mela in Maharashtra, India.

PARTICIPANTS

494 consenting 18-90 years old adults attending the 2015 Kumbh Mela were tested.

RESULTS

TES and routine health screenings identified unique clinical conditions in distinct patients. Intraoral fluorescent imaging classified 63.3% of the population with dental caries and periodontal diseases. An association between poor oral health and cardiovascular illnesses was also identified. Tympanic membrane imaging detected eardrum abnormalities in 13.0% of the population, several with a medical history of hearing difficulties. Gait and coordination issues were discovered in eight subjects and one subject had arrhythmia. Cross-correlations were observed between low oxygen saturation and low body mass index (BMI) with smokers (p=0.0087 and p=0.0122, respectively), and high BMI was associated with elevated blood pressure in middle-aged subjects.

CONCLUSIONS

TES synergistically identified clinically significant abnormalities in several subjects who otherwise presented as normal in routine health screenings. Physicians validated TES findings and used routine health screening data and medical history responses for comprehensive diagnoses for at-risk patients. TES identified high prevalence of oral diseases, hypertension, obesity and ophthalmic conditions among the middle-aged and elderly Indian population, calling for public health interventions.

Graphical and statistical analyses of the oculocardiac reflex during a non-invasive intracranial pressure measurement

PURPOSE

This study aimed to examine the incidence of the oculocardiac reflex during a non-invasive intracranial pressure measurement when gradual external pressure was applied to the orbital tissues and eye.

METHODS

Patients (n = 101) and healthy volunteers (n = 56) aged 20-75 years who underwent a non-invasive intracranial pressure measurement were included in this retrospective oculocardiac reflex analysis. Prespecified thresholds greater than a 10% or 20% decrease in the heart rate from baseline were used to determine the incidence of the oculocardiac reflex.

RESULTS

None of the subjects had a greater than 20% decrease in heart rate from baseline. Four subjects had a greater than 10% decrease in heart rate from baseline, representing 0.9% of the total pressure steps. Three of these subjects were healthy volunteers, and one was a glaucoma patient.

CONCLUSION

The incidence of the oculocardiac reflex during a non-invasive intracranial pressure measurement procedure was very low and not associated with any clinically relevant effects.

The cost and cost-effectiveness of rapid testing strategies for yaws diagnosis and surveillance

Background

Yaws is a non-venereal treponemal infection caused by Treponema pallidum subspecies pertenue. The disease is targeted by WHO for eradication by 2020. Rapid diagnostic tests (RDTs) are envisaged for confirmation of clinical cases during treatment campaigns and for certification of the interruption of transmission. Yaws testing requires both treponemal (trep) and non-treponemal (non-trep) assays for diagnosis of current infection. We evaluate a sequential testing strategy (using a treponemal RDT before a trep/non-trep RDT) in terms of cost and cost-effectiveness, relative to a single-assay combined testing strategy (using the trep/non-trep RDT alone), for two use cases: individual diagnosis and community surveillance.

Methods

We use cohort decision analysis to examine the diagnostic and cost outcomes. We estimate cost and cost-effectiveness of the alternative testing strategies at different levels of prevalence of past/current infection and current infection under each use case. We take the perspective of the global yaws eradication programme. We calculate the total number of correct diagnoses for each strategy over a range of plausible prevalences. We employ probabilistic sensitivity analysis (PSA) to account for uncertainty and report 95% intervals.

Results

At current prices of the treponemal and trep/non-trep RDTs, the sequential strategy is cost-saving for individual diagnosis at prevalence of past/current infection less than 85% (81–90); it is cost-saving for surveillance at less than 100%. The threshold price of the trep/non-trep RDT (below which the sequential strategy would no longer be cost-saving) is US$ 1.08 (1.02–1.14) for individual diagnosis at high prevalence of past/current infection (51%) and US$ 0.54 (0.52–0.56) for community surveillance at low prevalence (15%).

Discussion

We find that the sequential strategy is cost-saving for both diagnosis and surveillance in most relevant settings. In the absence of evidence assessing relative performance (sensitivity and specificity), cost-effectiveness is uncertain. However, the conditions under which the combined test only strategy might be more cost-effective than the sequential strategy are limited. A cheaper trep/non-trep RDT is needed, costing no more than US$ 0.50–1.00, depending on the use case. Our results will help enhance the cost-effectiveness of yaws programmes in the 13 countries known to be currently endemic. It will also inform efforts in the much larger group of 71 countries with a history of yaws, many of which will have to undertake surveillance to confirm the interruption of transmission.

Yaws is a non-venereal treponemal infection. The disease is targeted by WHO for eradication by 2020. Testing is envisaged for diagnosis to confirm of clinical cases during treatment campaigns and for surveillance to certify the interruption of transmission. However resources available to the global eradication programme are severely limited and the cost of testing must be contained. Testing requires simultaneous detection of antibodies to both treponemal and non-treponemal antigens for diagnosis of active infection. Currently, there is one commercially available rapid diagnostic test for yaws that can do just that. However, it is considerably more expensive than the available syphilis tests detecting treponemal antibodies only. We evaluate the cost and cost-effectiveness of a sequential testing strategy (using the treponemal test first, before the combined test), relative to a combined testing strategy (using only the combined test). We consider the two use cases: individual diagnosis and community surveillance. We find that the sequential strategy is cost-saving for both diagnosis and surveillance in most relevant settings. Yaws eradication programme should consider adopting the sequential strategy. Still, a cheaper trep/non-trep RDT is needed, costing no more than US$ 0.50–1.00. Our results will help enhance the cost-effectiveness of yaws programmes in the 13 countries known to be currently endemic. It will also inform efforts in the much larger group of 71 countries with a history of yaws, many of which will have to undertake surveillance to confirm the interruption of transmission.

Optoacoustic diagnostic modality: from idea to clinical studies with highly compact laser diode-based systems

Optoacoustic (photoacoustic) diagnostic modality is a technique that combines high optical contrast and ultrasound spatial resolution. We proposed using the optoacoustic technique for a number of applications, including cancer detection, monitoring of thermotherapy (hyperthermia, coagulation, and freezing), monitoring of cerebral blood oxygenation in patients with traumatic brain injury, neonatal patients, fetuses during late-stage labor, central venous oxygenation monitoring, and total hemoglobin concentration monitoring as well as hematoma detection and characterization. We developed and built optical parametric oscillator-based systems and multiwavelength, fiber-coupled highly compact, laser diode-based systems for optoacoustic imaging, monitoring, and sensing. To provide sufficient output pulse energy, a specially designed fiber-optic system was built and incorporated in ultrasensitive, wideband optoacoustic probes. We performed preclinical and clinical tests of the systems and the optoacoustic probes in backward mode for most of the applications and in forward mode for the breast cancer and cerebral applications. The high pulse energy and repetition rate allowed for rapid data acquisition with high signal-to-noise ratio from cerebral blood vessels, such as the superior sagittal sinus, central veins, and peripheral veins and arteries, as well as from intracranial hematomas. The optoacoustic systems were capable of automatic, real-time, continuous measurements of blood oxygenation in these blood vessels.

Cervical flexion-rotation test and physiological range of motion - A comparative study of patients with myogenic temporomandibular disorder versus healthy subjects

BACKGROUND

Temporomandibular Disorders (TMD) refer to several common clinical disorders which involve the masticatory muscles, the temporomandibular joint (TMJ) and the adjacent structures. Although neck signs and symptoms are found with higher prevalence in TMD patients compared to the overall population, whether limitation of cervical mobility is an additional positive finding in this cohort is still an open question.

OBJECTIVE

To compare the physiological cervical range of motion (CROM) and the extent of rotation during cervical flexion (flexion-rotation test, FRT) in people with TMD (muscular origin) and healthy control subjects.

METHOD

The range of motion of the neck and FRT was measured in 20 women with myogenic TMD and 20 age matched healthy controls.

RESULTS

Women with myogenic TMD had significantly lower FRT scores compared to their matched healthy women. No difference was found between groups in CROM in any of the planes of movement. The FRT was positive (less than 32°) in 90% of the TMD participants versus 5% in the healthy control but the findings were not correlated with TMD severity.

CONCLUSION

The results point out a potential involvement of the upper cervical joints (c1-c2) in women with myogenic TMD.

Use of a Tuning Fork for Fracture Evaluation: An Introduction for Education and Exposure

Radiographs, bones scans, and even ultrasound may be rare in the austere or acute environment for the evaluation of suspected musculoskeletal fractures. Having an easy, simple, and confident means of objective evaluation used in conjunction with the patient presentation, history, and physical findings may provide a more efficient and economical means of treatment. This introduction and review of selected literature are meant to provide a fuller understanding and consideration for the methods of using a tuning fork in fracture assessment.

Using drinking data and pharmacokinetic modeling to calibrate transport model and blind deconvolution based data analysis software for transdermal alcohol biosensors

Alcohol researchers/clinicians have two ways to collect subject /patient field data, standard-drink self-report and the breath analyzer, neither of which is passive or accurate because active subject participation is required. Transdermal alcohol sensors have been developed to measure transdermal alcohol concentration (TAC), but they are used primarily as abstinence monitors because converting TAC into more meaningful blood/breath alcohol concentration (BAC/BrAC) is difficult. In this paper, BAC/BrAC is estimated from TAC by first calibrating forward distributed parameter-based convolution models for ethanol transport from the blood through the skin using patient-collected drinking data for a single drinking episode and a nonlinear pharmacokinetic metabolic absorption/elimination model to estimate BAC. TAC and estimated BAC are then used to fit the forward convolution filter. Nonlinear least squares with adjoint-based gradient computation are used to fit both models. Calibration results are compared with those obtained using BAC/BrAC from alcohol challenges and from standard, linear, metabolic absorption, and zero order kinetics-based elimination models, by considering peak BAC, time of peak, and area under the BAC curve. Our models (with population parameters) could be included in a smart phone app that makes it convenient for the subject/patient to enter drinking data for a single episode in the field.

Measurement of Electrical Skin Impedance of Dermal-Visceral Zones as a Diagnostic Tool for Disorders of the Immune System

Among complementary medicine approaches, diagnostic screening tools based on neuroreflexology have been recently developed. Such techniques are based on the rationale that measurement of electrical impedance of specific dermal zones might reflect the occurrence of pathological states in the corresponding internal organs or systems. Our objective was to evaluate the reliability of a neuroreflexology-based diagnostic test in diagnosing immune-mediated diseases in a blinded single centre study. Seventy-eight patients with immune-mediated diseases (38 patients with autoimmune diseases (AD), and 40 allergic patients) were included in the study. Thirty age and sex matched healthy subjects were also evaluated as a control group. All the patients and subjects underwent conventional medical history and physical examination. We evaluated a device manufactured by Medex Screen Ltd (Arad, Israel). The Medex Test analysis was carried out by a second physician who was blinded to the previous diagnosis. A high correlation between the formal clinical diagnosis and the results of the measurement of electrical skin impedance was reported, with a specificity of 93.3% and a sensitivity of 81.2%. Both sensitivity and specificity dropped when analysing the autoimmune and the allergic group separately, but remained significant for the autoimmune diseases. Degree of activity of the allergic disorders, or specific treatment, did not affect the diagnostic properties of the described device. The Medex Test neurophysiology based technique has the potential to serve as a diagnostic tool for immune based pathologies. Future studies will define this tool place in routine evaluation and potential screening ability.

Some Effects of a Topical Collagen-Based Matrix on the Microcirculation and Wound Healing in Patients With Chronic Venous Leg Ulcers: Preliminary Observations

Themicrocirculation of the wound bed is a key parameter for improving granulation tissue formation and, hence, wound healing. The aim of this study was to determine whether a wound dressing comprising collagen/oxidized regenerated cellulose has effects over a short term on wound healing. Wounds were evaluated using a clinical wound score; pain associated with wounds was measured using a visual analogue scale. Wound microcirculation was evaluated using a technique based on noncontact remission spectroscopy. A prospective trial was performed in 40 patients with chronic venous leg ulcers (mean age 74 years; range, 43-93 years; 25 females and 15 males). Patients in group A were treated with PROMOGRAN® Matrix (Johnson& Johnson, New Brunswick, NJ) combined with “good” ulcer care for 2 weeks. Control group B consisted of 10 patientswho received only good ulcer care. The authors measured a favorable clinical response in 76.9% (group A) versus 66.7% (group B). Themean reduction of ulcer area was statistically significant in group A (P < .05). The wound score improved in group A from 2.28 ± 1.24 (before treatment) increasing to 3.72 ± 1.57 (after 1 week; P < .00023) and 4.92 ± 1.68 (after 2 weeks; P < .000027). In group B, the score improved from 1.44 ± 1.33 (before treatment) to 3.22 ± 1.30 (after 1 week; P < .0077). The mean visual analogue pain score before treatment was 8.72 (group A) and 7.88 (group B) (ns,P > .05). After 1 week of treatment, the score dropped to 5.76 (group A) and 6.66 (group B). In the second week, group A patients had a mean pain score of 3.84 compared with the pain score before treatment (P < .05). After 1 week of treatment, in group A there was a decrease in remission spectroscopy, which is considered to reflect an improvement in microcirculation.

An Integrated Circuit for Chip-Based Analysis of Enzyme Kinetics and Metabolite Quantification

We have created a novel chip-based diagnostic tools based upon quantification of metabolites using enzymes specific for their chemical conversion. Using this device we show for the first time that a solid-state circuit can be used to measure enzyme kinetics and calculate the Michaelis-Menten constant. Substrate concentration dependency of enzyme reaction rates is central to this aim. Ion-sensitive field effect transistors (ISFET) are excellent transducers for biosensing applications that are reliant upon enzyme assays, especially since they can be fabricated using mainstream microelectronics technology to ensure low unit cost, mass-manufacture, scaling to make many sensors and straightforward miniaturisation for use in point-of-care devices. Here, we describe an integrated ISFET array comprising 2(16) sensors. The device was fabricated with a complementary metal oxide semiconductor (CMOS) process. Unlike traditional CMOS ISFET sensors that use the Si3N4 passivation of the foundry for ion detection, the device reported here was processed with a layer of Ta2O5 that increased the detection sensitivity to 45 mV/pH unit at the sensor readout. The drift was reduced to 0.8 mV/hour with a linear pH response between pH 2-12. A high-speed instrumentation system capable of acquiring nearly 500 fps was developed to stream out the data. The device was then used to measure glucose concentration through the activity of hexokinase in the range of 0.05 mM-231 mM, encompassing glucose's physiological range in blood. Localised and temporal enzyme kinetics of hexokinase was studied in detail. These results present a roadmap towards a viable personal metabolome machine.

Translating diagnostic assays from the laboratory to the clinic: analytical and clinical metrics for device development and evaluation

As lab-on-a-chip health diagnostic technologies mature, there is a push to translate them from the laboratory to the clinic. For these diagnostics to achieve maximum impact on patient care, scientists and engineers developing the tests should understand the analytical and clinical statistical metrics that determine the efficacy of the test. Appreciating and using these metrics will benefit test developers by providing consistent measures to evaluate analytical and clinical test performance, as well as guide the design of tests that will most benefit clinicians and patients. This paper is broken into four sections that discuss metrics related to general stages of development including: (1) laboratory assay development (analytical sensitivity, limit of detection, analytical selectivity, and trueness/precision), (2) pre-clinical development (diagnostic sensitivity, diagnostic specificity, clinical cutoffs, and receiver-operator curves), (3) clinical use (prevalence, predictive values, and likelihood ratios), and (4) case studies from existing clinical data for tests relevant to the lab-on-a-chip community (HIV, group A strep, and chlamydia). Each section contains definitions of recommended statistical measures, as well as examples demonstrating the importance of these metrics at various stages of the development process. Increasing the use of these metrics in lab-on-a-chip research will improve the rigor of diagnostic performance reporting and provide a better understanding of how to design tests that will ultimately meet clinical needs.

Analytical applications of MIPs in diagnostic assays: future perspectives

Many efforts have been made to produce artificial materials with biomimetic properties for applications in binding assays. Among these efforts, the technique of molecular imprinting has received much attention because of the high selectivity obtainable for molecules of interest, robustness of the produced polymers, simple and short synthesis, and excellent cost efficiency. In this review, progress in the field of molecularly imprinted sorbent assays is discussed-with a focus on work conducted from 2005 to date.

Precision chemical heating for diagnostic devices

Decoupling nucleic acid amplification assays from infrastructure requirements such as grid electricity is critical for providing effective diagnosis and treatment at the point of care in low-resource settings. Here, we outline a complete strategy for the design of electricity-free precision heaters compatible with medical diagnostic applications requiring isothermal conditions, including nucleic acid amplification and lysis. Low-cost, highly energy dense components with better end-of-life disposal options than conventional batteries are proposed as an alternative to conventional heating methods to satisfy the unique needs of point of care use.

Technological advances in bovine mastitis diagnosis: an overview

Bovine mastitis is an economic burden for dairy farmers and preventive control measures are crucial for the sustainability of any dairy business. The identification of etiological agents is necessary in controlling the disease, reducing risk of chronic infections and targeting antimicrobial therapy. The suitability of a detection method for routine diagnosis depends on several factors, including specificity, sensitivity, cost, time in producing results, and suitability for large-scale sampling of milk. This article focuses on current methodologies for identification of mastitis pathogens and for detection of inflammation, as well as the advantages and disadvantages of different methods. Emerging technologies, such as transcriptome and proteome analyses and nano- and microfabrication of portable devices, offer promising, sensitive methods for advanced detection of mastitis pathogens and biomarkers of inflammation. The demand for alternative, fast, and reliable diagnostic procedures is rising as farms become bigger. Several examples of technological and scientific advances are summarized which have given rise to more sensitive, reliable and faster diagnostic results.

[Consanguinity between meridian theory and Bianque's pulse theory]

The integral meridian theory is composed of five parts, including meridian course, syndrome, diagnostic method, treating principle and treatment, and the core of it is meridian syndrome. It has been proved by multiple evidences that the meridian syndrome induced by the pathological change in meridian and the death syndrome of pulse penetrating or attaching to the syndrome are all originated from Bianque' s facial color and pulse diagnosis. And regarding the pulse syndrome,there are many different interpretations based on the theory of yin-yang in four seasons before the Han Dynasty. The emerging of Biaoben diagnostic method in Bianque's pulse method and its extensive clinical application promote a new theoretic interpretation the connection of meridians interpreting pulse syndrome directly. Besides, along with the new development of blood-pulse theory of Bianque's medicine, the revolution on meridian theory is aroused as well its theoretical paradigm turning from "tree" type to "ring" type. In other words, Bianque's medicine not only gives birth to meridian theory, but also decides its final development.

[Analysis on renving and cunkou pulse diagnostic methods in Internal Classic and Pulse Classic]

Renying and cunkou pulse diagnostic methods have been recorded in Neijing Unternal Classic) and Maijing (Pulse Classic) and these two pulse diagnostic methods are very different. Through the analysis and inference on the relevant statements in Internal Classic and Pulse Classic, as well as those of medical scholars in later generations, it is discovered that the pulse of excess type, the pulse of deficiency type, the tense pulse, the regular missed-beat pulse, etc. could be detected and be used to judge the disorders of meridians and zangfu organs by the comparison between the pulse of excess type and the pulse of deficiency type with renying and cunkou pulse diagnostic methods recorded in Internal Classic. The substance of renying and cunkou pulse diagnostic methods in Pulse Classic is consistent with the methods in later generations, meaning that they can be applied to judge the disorders of meridians and zangfu organs through detecting the excess or the deficiency in every region of cun, guan and chi.

[Telemedicine in your suitcase: useful tools for the traveler]

In our digital age, telemedicine becomes, under various forms, a useful companion for the traveler, providing access to up-to-date information about health and security risks, remote consultation of specialists to ascertain a diagnosis of select an appropriate treatment, connection to similar patients in order to obtain contextualized advice, biomedical sensors and other monitoring and diagnostic portable tools, as well as transportable electronic health records enabling continuity of care and mobility. Commercial telemedicine services are being developed specifically for travelers, most of which are using mobile phones as the main device, which thus becomes a real telestethoscope.

New system for tracking a device for diagnosing scalp skin

In scalp skin examinations, it is difficult to find a previously treated region on a patient's scalp through images captured by a camera attached to a diagnostic device because the zoom lens on camera has a small field of view. Thus, doctors manually record the region on a chart or manually mark the region. However, this process is slow and inconveniences the patient. Thus, we propose a new system for tracking the diagnostic device for the scalp skin of patients. Our research is novel in four ways. First, our proposed system consists of two cameras to capture the face and the diagnostic device. Second, the user can easily set the position of camera to capture the diagnostic device by manually moving a frame to which the camera is attached. Third, the position of patient's nostrils and corners of the eyes are detected to align the position of his/her head more accurately with the recorded position from previous sessions. Fourth, the position of the diagnostic device is continuously tracked during the examination through images that help detect the position of the color marker attached to the device. Experimental results show that our system has a higher performance than conventional method.

Efficacy and complications of computed tomography-guided hook wire localization

BACKGROUND

Video-assisted thoracic surgery offers a minimally invasive method for diagnosing and treating small pulmonary lesions, although the localization of these lesions is sometimes problematic. Various localization methods have been reported but few studies have described their efficacy and adverse events.

METHODS

We performed computed tomography (CT)-guided localization using a hook wire in 417 patients with 500 lesions treated between January 2006 and December 2010.

RESULTS

We located 178 lesions with a ground-glass opacity component and 322 solid lesions. The solid lesions had smaller tumor diameters and were located further from the pleura. Tumor depth to size ratio was 0.9 ± 0.9 for the lesions with a ground-glass opacity component and 1.8 ± 1.5 for the solid lesions (p < 0.001). Pneumothorax requiring aspiration was observed in 4.6% patients, and hemoptysis and pulmonary hematoma was observed in 10.3%. Systemic air embolism with no sequelae and spontaneous resolution occurred in a patient (0.24%). The morbidity rate was 15.1%. Male patients, patients who had undergone multiple localization, and heavy smokers were at a higher risk of pneumothorax requiring aspiration. Insertion distance more than 25 mm was a risk factor for hemoptysis and pulmonary hematoma (p < 0.001). Procedure duration per lesion was 14 ± 5 minutes. Dislodgement occurred in 2 patients (0.4%).

CONCLUSIONS

The safety, reliability, and convenience of CT-guided hook wire localization are acceptable. Localization for lesions with a ground-glass opacity component may be performed when the lesions are relatively large and shallow. Insertion distances greater than 25 mm are associated with a risk of pulmonary hematoma and hemoptysis.

Health-related quality of life assessment after antiretroviral therapy: a review of the literature

Antiretroviral (ARV) treatment for HIV infection has resulted in significant improvement in immunologic and virologic parameters, as well as a reduction in AIDS-defining illnesses and death. Over 25 medications are approved for use, usually in combination regimens of three or four ARVs. Several ARVs are now available as combinatorial products, which have been associated with better adherence. However, while ARV therapy has prolonged life, ARVs also pose a challenge for quality of life as they can cause significant side effects in addition to the potential for drug toxicity and interaction. Given the many complications, side effects and symptoms of HIV/AIDS in addition to associated medical and psychiatric co-morbidities, the need to understand and assess how these interactions may affect health-related quality of life (HRQOL) has grown. Numerous instruments (some validated, others not) are available and have been applied to understanding how ARV treatment affects HRQOL in those with HIV infection, both in clinical trials and clinical practice. In general, ARV treatment improves HRQOL, but this is dependent on the population being studied, the HRQOL instrument being used and the timeframe during which HRQOL has been studied. This article provides a review of the literature on quality of-life assessment as it relates to ARV treatment in developed countries and briefly reviews the HRQOL instruments used, how they have been applied to ARV utilization, and where future research should be applied in HRQOL assessment and HIV infection.

Rapid diagnosis of Mycobacterium tuberculosis with Truenat MTB: a near-care approach

Background

Control of the global Tuberculosis (TB) burden is hindered by the lack of a simple and effective diagnostic test that can be utilized in resource-limited settings.

Methods

We evaluated the performance of Truenat MTB™, a chip-based nucleic acid amplification test in the detection of Mycobacterium tuberculosis (MTB) in clinical sputum specimens from 226 patients with suspected pulmonary tuberculosis (TB). The test involved sputum processing using Trueprep-MAG™ (nanoparticle-based protocol run on a battery-operated device) and real-time PCR performed on the Truelab Uno™ analyzer (handheld, battery-operated thermal cycler). Specimens were also examined for presence of MTB using smear microscopy, liquid culture and an in-house nested PCR protocol. Results were assessed in comparison to a composite reference standard (CRS) consisting of smear and culture results, clinical treatment and follow-up, and radiology findings.

Results

Based on the CRS, 191 patients had “Clinical-TB” (Definite and Probable-TB). Of which 154 patients are already on treatment, and 37 were treatment naïve cases. Remaining 35 were confirmed “Non-TB” cases which are treatment naïve cases. The Truenat MTB test was found to have sensitivity and specificity of 91.1% (CI: 86.1–94.7) and 100% (CI: 90.0–100) respectively, in comparison to 90.58% (CI: 85.5–94.3) and 91.43% (CI: 76.9–98.2) respectively for the in-house nested PCR protocol.

Conclusion

This preliminary study shows that the Truenat MTB test allows detection of TB in approximately one hour and can be utilized in near-care settings to provide quick and accurate diagnosis.

Overview of the microfluidic diagnostics commercial landscape

Since its birth in the late 1980s, the field of microfluidics has continued to mature, with a growing number of companies pursuing diagnostic applications. In 2009 the worldwide in vitro diagnostics market was estimated at >$40 billion USD, and microfluidic diagnostics are poised to reap a significant part of this market across a range of areas including laboratory diagnostics, point-of-care diagnostics, cancer diagnostics, and others. The potential economic advantages of microfluidics are numerous and compelling: lower reagent and/or sample volumes, lower equipment costs, improved portability, increased automation, and increased measurement speed. All of these factors may help put more information in the hands of doctors and patients sooner, enabling earlier disease detection and more tailored, effective treatments. This chapter reviews the microfluidic diagnostics commercial landscape and discusses potential commercialization challenges and opportunities.

Introduction to in vitro diagnostic device regulatory requirements

A common application for microfluidics can be found in medical devices where the advantages of small volume measuring equipment can be exploited for In Vitro Diagnostics. This chapter focuses on the US and the EU regulations, explaining the broad landscape and regulatory pathways of each market.

Three-dimensional, paper-based microfluidic devices containing internal timers for running time-based diagnostic assays

This chapter describes a method for fabricating three-dimensional (3D), paper-based microfluidic devices that contain internal timers for running quantitative, time-based assays. The method involves patterning microfluidic channels into paper, and cutting double-sided adhesive tape into defined patterns. Patterned paper and tape are assembled layer by layer to create 3D microfluidic devices that are capable of distributing microliter volumes of a sample into multiple regions on a device for conducting multiple assays simultaneously. Paraffin wax is incorporated into defined regions within the device to provide control over the distribution rate of a sample, and food coloring is included in defined regions within the device to provide an unambiguous readout when the sample has reached the bottom of the device (this latter feature is the endpoint of the timer).

Present technology and future trends in point-of-care microfluidic diagnostics

This work reviews present technologies and developing trends in Point-of-Care (POC) microfluidic diagnostics platforms. First, various fluidics technologies such as pressure-driven flows, capillary flows, electromagnetically driven flows, centrifugal fluidics, acoustically driven flows, and droplet fluidics are categorized. Then three broad categories of POC microfluidic testing devices are considered: lateral flow devices, desktop and handheld POC diagnostic platforms, and emergent molecular diagnostic POC systems. Such evolving trends as miniaturization, multiplexing, networking, new more sensitive detection schemes, and the importance of sample processing are discussed. It is concluded that POC microfluidic diagnostics has a potential to improve patient treatment outcome and bring substantial savings in overall healthcare costs.