Dissertations / Theses on the topic 'Sports medicine Equipment and supplies'

Coded-aperture imaging without detector motion can be used to reconstruct three-dimensional radionuclide distributions in the context of nuclear medicine. This approach offers several advantages over the rotating gamma-ray camera systems presently employed in the clinic. These advantages include improved sensitivity, potentially better spatial resolution, and the capability of doing dynamic studies. There are two problems associated with the coded-aperture approach, however. First, the data is "multiplexed", which refers to the fact that many line integrals of the source distribution are combined together and not measured individually, so that information is lost. Second, the number of resolvable detector elements is typically an order of magnitude less than the number of object elements to be reconstructed, so that the reconstruction problem is underdetermined. Consequently, the reconstruction is not unique. By using various types of a priori information in forming the reconstruction, however, it is possible to augment the incomplete data set. Two algorithms are presented to reconstruct objects from their coded-image projections and various types of a priori information. The first, a Monte Carlo algorithm, is a flexible and computationally efficient approach using the a priori knowledge of positivity and nearest-neighbor correlation. This algorithm is used to qualitatively explore the effect of the data-taking geometry on reconstruction performance. The second algorithm is a linear estimator incorporating as a priori knowledge completely general first- and second-order statistical information about the object class to be reconstructed. The linear-estimator formalism also provides a minimum-variance expression for system optimization. This linear algorithm is used to explore the effects of correct and incorrect a priori information on reconstruction performance, and to quantitatively investigate reconstruction quality with respect to data-taking geometry.

The Hotelling trace criterion (HTC) is a measure of class separability used in pattern recognition to find a set of linear features that optimally separate two classes of objects. In this dissertation we use the HTC not as a figure of merit for features, but as a figure of merit for characterizing imaging systems and designing filters for feature enhancement in nuclear medicine. If the HTC is to be used to optimize systems, then it must correlate with human observer performance. In our first study, a set of images, created by overlapping ellipses, was used to simulate images of livers. Two classes were created, livers with and without tumors, with noise and blur added to each image to simulate nine different imaging systems. Using the ROC parameter dₐ as our measure, we found that the HTC has a correlation of 0.988 with the ability of humans to separate these two classes of objects. A second study was performed to demonstrate the use of the HTC for system optimization in a realistic task. For this study we used a mathematical model of normal and diseased livers and of the imaging system to generate a realistic set of liver images from nuclear medicine. A method of adaptive, nonlinear filtering which enhances the features that separate two sets of images has also been developed. The method uses the HTC to find the optimal linear feature operator for the Fourier moduli of the images, and uses this operator as a filter so that the features that separate the two classes of objects are enhanced. We demonstrate the use of this filtering method to enhance texture features in simulated liver images from nuclear medicine, after using a training set of images to obtain the filter. We also demonstrate how this method of filtering can be used to reconstruct an object from a single photon-starved image of it, when the object contains a repetitive feature. When power spectrums for real liver scans from nuclear medicine are calculated, we find that the three classifications that a physician uses, normal, patchy, and focal, can be described by the fractal dimension of the texture in the liver. This fractal dimension can be calculated even for images that suffer from much noise and blur. Given a simulated image of a liver that has been blurred and imaged with only 5000 photons, a texture with the same fractal dimension as the liver can be reconstructed.

The EPID (electronic portal imaging device) was designed for in vivo imaging of patients during radiotherapy treatment. The ability of EPIDs to promptly acquire two dimensional data, lends them to be considered for use in quality assurance of the linac. This thesis set out to investigate the possibility of using a radionuclide, technetium 99 m (Tc99m), to produce a flood field for the calibration of an EPID, because using a beam calibrated EPID to measure the beam is self-referential. The difference in relative response between the energy spectrum of a 6MV beam and the Tc99m was investigated using EGSNRC DoseXYZ Monte Carlo Modelling. The relative output ratio was calculated to be less than 1.6%. The dose response of the EPID with respect to dose rate was checked using different activities of Tc99m and found to be linear. The flatness from a phantom was calculated, with a model in MATLAB, for a range of heights, overlaps, thickness, and deformations, to find the optimum balances between signal strength and flatness. This model was checked for accuracy using diagnostic radiographic film. The culmination of the energy response, linearity and the calculated flatness is a flood field taken with a flood phantom on the EPID with low signal strength. To get a signal to noise ratio of 3% the mean of over 2000 flood field images were used. This accuracy was not adequate for clinical use but the averaging of pixels it is accurate enough for QA.

High resolution imaging devices have made a digital medical archiving system feasible. The large volumes of information generated must be stored and retrieved at high data rates in order to insure the timely diagnosis of patients. This creates some unique technological challenges that must be resolved, including the problem dealing with multiple vendor products interacting in one environment. The high speed interface card design presented in this thesis is able to deal with different computer host busses as well as different interprocessor communication protocols. The ACR-NEMA standard has been implemented in the design as one possible network protocol that provides a solution that can be easily adapted to different vendors. The design has been analyzed using the Network II.5 simulation language. The simulation was performed to insure that the original objectives are met and to determine the impact on the protocols rated throughput.

Bag-valve mask (BVM) ventilation maintains a patient's oxygenation and ventilation until a more definitive artificial airway can be established. In the prehospital setting of a traffic collision or medical aid scene this is performed by an Emerency Medical Technician or medical first responder. Few studies have looked at the effectiveness of Bag-valve masks (BVM) or the complication rate of ventilating an unprotected airway. The purpose and goal of this study is to educate both medical first responders and basic emergency medical technicians.

Research shows that up to 80% of recreational skiers have lower limb alignments which can impede their ability to turn their skis properly (Subotnick,1982). The most difficult of these alignment problems to control within a ski-boot is the varus alignment of the subtalar joint (Macintyre and Matheson, 1988). The use of custom molded footbeds made specifically for use inside of ski boots has been suggested as one method of compensating for a varus aligned foot. This study compared the effectiveness of one brand of custom molded ski boot footbed with that of a noncustom insole in controlling the motions of the lower limb associated with subtalar varus. Specifically these motions were those of the rearfoot and the navicular tubercle, along with the alignment of the tibial tuberosity with respect to the mid-line of the ski boot. In addition, subjects were given the opportunity to assess their subjective feelings of edge control, pain, and fatigue while skiing with both the custom molded footbeds and non-custom insoles. The subject group for this study consisted of 13 advanced level adult skiers who demonstrated more than three degrees of subtalar varus when non-weight bearing. Each subject received a pair of custom molded ski boot footbeds at the beginning of the study. Ski boots that had been cut away at the rear and the medial side were used in the laboratory in order to observe the motions of the navicular tubercle and the rearfoot as the subject transferred their weight in a simulated skiing motion. The right and left navicular tubercle, tibial tubercle, and the insertion of the Achilles at the calcaneus of each subject were located by palpation and marked. After sufficient practice of the weight transfer motion, two trials of each landmark were photographed using 35mm slide film. The subjects were first photographed while using the non-custom insoles and again using the custom molded footbeds. The slides were digitized and comparisons were made between the two types of insoles for both the start and end locations of the landmarks as well as for the ranges of motion through which the landmarks traveled. Statistical analyses of the group results indicated that there was significantly less (p=0.000) navicular motion during the shift from the start to the end positions with the use of the custom molded footbeds as compared to the non-custom insoles. The rearfoot angle was significantly less at both the start (p=0.000) and end (p=0.000) positions with the use of the custom footbeds as compared to the noncustom insoles. There was no statistical difference between the amount of rearfoot motion allowed by either type of insole. The tibial tubercle was positioned significantly (p=0.000) closer to the mid-line of the ski boot when using the custom footbeds than with the use of the non-custom insoles. These results indicate that the custom footbeds domaintain the subtalar joint in a more neutral position than do non-custom insoles. During the skiing section of the study the subjects rated the custom footbeds as providing better edge control (p=0.000) and resulting in less fatigue (p=0.000) than noncustom insoles. There was no statistical significance when comparing the ratings given by the group for the level of pain experienced with the use of either type of insole. There was a statistically significant improvement (p=0.000) in race times for the group when using the custom footbeds as compared to the non-custom insoles. The results of this study indicate that custom molded ski boot footbeds are able to control subtalar motion more effectively than a non-custom insole. It appears that this control of subtalar motion enhances the skiing experience by increasing edge control and reducing the amount of fatigue experienced.
Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate

Thesis (M.S.)--Medical College of Ohio, 2004.
"In partial fulfillment of the requirements for the degree of Master of Science in Occupational Health." Major advisor: Farhang Akbar. Includes abstract. Document formatted into pages: iv, 75 p. Title from title page of PDF document. Includes bibliographical references (p. 58-68).

In recent years, a growing number of diagnostic examinations in a hospital are being generated by digitally formatted imaging modalities. The evolution of these systems has led to the development of a totally digitized imaging system, which is called Picture Archiving and Communication System (PACS). A high speed computer network plays a very important role in the design of a Picture Archiving and Communication System. The computer network must not only offer a high data rate, but also it must be structured to satisfy the PACS requirements efficiently. In this dissertation, a computer network, called PACnet, is proposed for PACS. The PACnet is designed to carry image, voice, image pointing overlay, and intermittent data over a 200 Mbps dual fiber optic ring network. The PACnet provides a data packet channel and image and voice channels based on Time Division Multiple Access (TDMA) technique. The intermittent data is transmitted over a data packet channel using a modified token passing scheme. The voice and image pointing overlay are transferred between two stations in real-time to support the consultive nature of a radiology department using circuit switching techniques. Typical 50 mega-bit images are transmitted over the image channel in less than a second using circuit switching techniques. A technique, called adaptive variable frame size, is developed for PACnet to achieve high network utilization and short response time. This technique allows the data packet traffic to use any residual voice or image traffic momentarily available due to variation in voice traffic or absence of images. To achieve optimal design parameters for network and interfaces, the PACnet is also simulated under different conditions.

Sudden cardiac death (SCD) is responsible for 300,000 deaths in the United States each year. Of these 300,000 deaths, 3,000-5,000 are younger adults (18-40 years) (American Heart Association (AHA), 2005; Sudden Arrhythmia Death Syndromes Foundation (SADS), 2005). Implanted cardioverter defibrillators have become the treatment of choice for individuals with life threatening arrhythmias (Cannom Prystowsky, 2004; Glikson & Friedman, 2001; Josephson, Hein, & Wellens, 2004). Although this life sustaining technology has been found to be effective in terminating life threatening arrhythmias, adjustment to an ICD may be difficult for some patients (Ganz, 2004). Few studies have investigated how younger adults manage life with an ICD (Sears, Burns, Handberg, Sotile, & Conti, 2001). It has been reported that older adults view the ICD as an extension of life, whereas, younger ICD recipients associate the ICD with significant life changes, body image concerns, and decreased independence (Arteaga & Windle, 1995). The purpose of this study was to describe the day-to-day experiences of younger adults (18-40 years old) [N = 20] living with an implanted cardioverter defibrillator. A qualitative descriptive design was used with naturalistic inquiry guiding data collection, management, and analysis. Using open-ended, in-depth interviews, younger adults were asked to describe their life after ICD implantation, physiological or psychosocial issues related to ICD implantation, and strategies used to manage life with an ICD. Data were managed using NVIVO software and analyzed using content analysis. The results revealed an overarching theme, A cautious transition to a new normal, with five subthemes: Initial diagnosis: anxiety and concern; Caution, awareness, and security: daily life with an ICD; Childbearing: passing my disease to my children; Financial concerns; and Strategies for living with an ICD: be positive and live life to the fullest. This study presented some of the unique developmental and transitional issues that younger adults with ICDs are facing and strategies they used to assist in adaptation to life with an ICD. Their experiences can provide the basis for intervention programs that are developmentally sensitive and age-specific.

Catheter-Associated Urinary Tract Infections are considered a clinical indicator of quality of care. A descriptive research study was conducted to identify the strategies used by hospitals to reduce or eliminate CAUTIs. Infection Control Preventionists were surveyed. In a predominately rural southeastern state, this study demonstrated that about 40% of hospitals surveyed are implementing CAUTI prevention processes.

This study correlated the performance accuracy of peripheral blood differentials evaluated by clinical laboratory scientists and clinical laboratory technicians. Fifty-one senior-year students from four clinical laboratory science baccalaureate programs and 37 second-year students from five clinical laboratory technician programs were given 10 peripheral blood differentials to perform. Results were compared to the values assigned by the Rajamaki method of proficiency testing. There was a significant discrepancy in the levels of accuracy between the two cohorts, suggesting that the results of peripheral blood differentials performed by clinical laboratory technicians is suspect. Facilities wishing to maintain or improve the quality of laboratory services should consider allowing only baccalaureate level clinical laboratory scientists to perform peripheral blood differentials.

Background: Tension pneumothorax is a condition with frequent fatal complications. This condition is caused by a disruption in the lung - that creates a one-way valve allowing air to accumulate in the pleural space. The fatal complication is the prevention of blood returning to the right side of the heart - due intrathoracic pressure compressing the right atrium. The patient can exhibit symptoms of dyspnea, tachypnea, tracheal deviation, jugular venous distention, subcutaneous emphysema, and shock that can lead to rapid deterioration and death. Case Report: We report a case of massive subcutaneous emphysema complicating tension pneumothorax management. The patient is a 20-year-old male who presented to the emergency department with chest trauma and was in extremis with diffuse severe subcutaneous emphysema. Due to the distorted anatomy, airway management and chest decompression were performed with nonstandard techniques/equipment resulting in rapid patient stabilization. After 4 days in the hospital, he was discharged home with no deficits. Discussion: Many providers do not have the proper equipment or training to treat patients in this extreme condition. CT images demonstrate the anatomical distortions in this case and the increase in size required for invasive life-saving devices. Images demonstrate where many commercial 14 gauge angiocaths and cricothyrotomy kits will not suffice (due to distortion in the anatomy), and these should not be relied on solely. Conclusions: While trauma carts frequently maintain (1.75 - 2 inch) 14 gauge angiocaths, they should also have military grade angiocaths that are 3.25” in length, which will work in most cases. Some, but not all, military-grade cricothyrotomy kits, or individually assembled kits, have 6.0 endotracheal tubes and come with a bougie and cricothyrotomy hook which would have been sufficient in this patient. Prehospital and hospital healthcare personnel should be prepared for similar patient encounters.

Thesis (MSc)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: A digital portal X-ray imaging system was developed to replace the radiographic X-ray films currently used for patient position verification at the National Accelerator Centre (NAC) proton therapy facility. The main advantage of a digital system is the short time in which the image can be obtained. Other advantages include optimisation of the image display, effective archiving of the digital images, access from various locations through data networks, and lower operational costs. The digital system described in this thesis consists of a Gd202S:Tb scintillator screen for converting X-rays to visible light, a protected aluminum front silvered mirror to direct the light to a Charge Coupled Device (CCD) camera for capture and a personal computer for data acquisition, processing and display. Compared with other digital imaging systems, this is a simple, compact and affordable system. The properties of the various components were investigated. The Rarex G-130 (Gd202S:Tb) scintillation screen was chosen for its good spatial resolution, high emission efficiency and good matching between the spectral emission wavelength peak and the quantum efficiency of the CCD camera. The spatial resolution measured for the system with a field of view (FOV) of 290 x 190 mnr' is 1.3 lp/mm, which can be improved by increasing the CCD chip resolution or decreasing the field of view, since the CCD camera limits the spatial resolution. Intrinsic detector noise determines the lower limit of the dynamic range of the detector and is reduced by cooling the CCD camera. A dark current exposure is subtracted from the image to remove the bias signal and background signal level mainly caused by thermal noise. Photon noise, beam in-homogeneity and efficiency variations across the CCD chip are removed by a flat field correction. The digital images obtained with this system compare very well with the currently used radiographic film images and they are satisfactory for the purpose of patient position verification. Using the digital system it is possible to reduce the patient dose by 19 % and still obtain satisfactory image quality.
AFRIKAANSE OPSOMMING: 'n Digitale X-straalafbeeldingstelsel is ontwikkel om die radiografiese X-straalfilm wat tans gebruik word vir die kontrolering van die pasientposisionering voor die toediening van protonterapie by die Nasionale Versnellersentrum, te vervang. Die voordeel van die digitale sisteem is dat die beelde feitlik onmiddellik beskikbaar is. Verdere voordele sluit die optimisering van die vertoon van beeldkontras, effektiewe liassering, vinnige bereik deur datanetwerke en lae lopende kostes in. Die digitale sisteem beskryf in die tesis bestaan uit 'n gadolinium oksi-sulfied (Gd202S:Tb) sintillasieskerm wat X-strale omskakel na sigbare lig, 'n eerste-oppervlak aluminiumspieël wat die lig na 'n digitale kamera (CCD kamera) weerkaats en In persoonlike rekenaar vir dataverwerwing, verwerking en vertoon. Vergeleke met ander digitale stelsels is hierdie digitale beeldingstelsel eenvoudig, kompak en bekostigbaar. Die eienskappe van die verskillende komponente van die stelsel is ondersoek. Die Rarex G- 130 (Gd202S:Tb) sintillasieskerm IS gekies vanweë goeie resolusie, hoë emissiedoeltreffendheid en die hoë omsettingsdoeltreffendheid van die digitale kamera by die spektrale emissiegolflengte van dié sintillasieskerm. Die ruimtelike oplosvermoë van die stelsel is bepaal met In veldgrootte van 290 x 190 mnr' as 1.3 lynpare per millimeter. Die ruimtelike oplosvermoë kan verhoog word deur die kameraresolusie te verhoog of die veldgrootte te verklein, omdat die resolusie van die kamera tans die oplosvermoë van die stelsel beperk. Intrinsieke ruis van die detektor beperk die onderste grens van die dinamiese reikwydte van die detektor en kan verminder word deur die kamera te verkoel. 'n Donkerstroom-beeld word van die X-straalbeelde afgetrek om die voorspanningsein en die agtergrondsein, wat hoofsaaklik veroorsaak word deur termiese ruis, te verwyder. Ruis wat ontstaan as gevolg van fluktuasies in die aantal fotone, nie-homogeniteite in die bundel of variasie van die sensitiwiteit in die skerm word verwyder met behulp van 'n plat vlak beeld. Die digitale beelde verkry met die stelsel vergelyk goed met die beelde wat tans op film geneem word en die beeldkwalitiet is voldoende vir die kontrolering van die pasientopstelling. Dit is moontlik om die pasiëntdosis met 19 % te verminder en steeds voldoende beeldkwaliteit te verkry.

Thesis (Ph.D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Skrinjar, Oskar; Committee Member: Oshinski, John; Committee Member: Tannenbaum, Allen; Committee Member: Vela, Patricio; Committee Member: Yezzi, Anthony

Background. Primary and secondary prevention trials have shown that implantable cardioverter-defibrillators (ICD) reduce the risk of cardiac death, but concerns have been raised regarding the psychological well-being of ICD patients. Anxiety can affect a significant proportion of these patients, but there is limited information about prevalence and determinants of anxiety after the implementation of the more recent guidelines for ICD implantation. Several behavioral interventions have been effective in improving anxiety in these patients, however the efficacy of mindfulness-based interventions (MBI) has not been investigated in ICD patients, and there is limited information regarding the characteristics of pre-intervention, “dispositional” mindfulness in patients with cardiovascular disease never exposed to mindfulness training. The aims of this dissertation project were: 1) To determine the feasibility of a randomized clinical trial of a phone-administered, mindfulness-based training program, as measured by recruitment and retention rates, treatment adherence and fidelity; 2) To evaluate the current baseline prevalence and determinants of anxiety in the study population and 3) To describe the correlates of dispositional mindfulness in the study population. Methods. The study was conducted at the Electrophysiology Service at the UMass Memorial Medical Center. All consecutive patients who recently underwent an ICD procedure or received ICD shocks were screened for eligibility to participate in a pilot randomized controlled trial in which an eight session, phone-delivered, weekly MBI was compared to a usual care condition. Assessments were performed at baseline and post-intervention. A cross-sectional design was used for aims 2 and 3. Anxiety was assessed using the Hospital Anxiety and Depression Scale; a shortened version of the Five Facets of Mindfulness questionnaire was used to evaluate mindfulness. Results. Thirty patients (21 M, 9 F; mean age 63.1 ±10.3 years) were enrolled in the study. The methods ultimately adopted to screen, recruit, and retain study participants were feasible to conduct and satisfactory to ICD outpatients, and the study intervention was safe. Phone delivery resulted in excellent retention rates and limited costs. Assessments of treatment fidelity showed that the content of the intervention was delivered as intended in almost 100% of cases. The study findings do not show a decrease in the overall prevalence of anxiety in ICD patients compared with earlier cohorts; anxiety was associated with young age, low socio-economic status and previous psychological morbidity, but not with ICD-related factors including prior shock delivery. Finally, baseline mindfulness was most strongly associated with previous psychological morbidity (in particular, depression), and current anxiety symptoms. Conclusion. Psychological morbidity appears to be the major determinant of anxiety in the patients currently enrolled in the study. Dispositional mindfulness is inversely associated with current anxiety and depression and with prior psychological morbidity, supporting the hypothesis of a modulating role of mindfulness on the processing of negative emotions. A phone-delivered, individual MBI is feasible, acceptable to patients and can be adequately delivered by trained instructors. The findings from this dissertation work support the need for larger clinical trials of MBI in ICD patients.

BACKGROUND: Emerging evidence suggests that the population of children assisted with respiratory medical equipment and supplies (RMES) is increasing in size and is having a substantial impact on families, providers, and the health system. Little is known on a population level about children who use RMES to compensate for a deficit in the ability to breathe. This study addressed these gaps by assessing (1) the characteristics of children in Medicaid using RMES and (2) how the use of RMES influences healthcare utilization and spending across the care continuum. METHODS: A retrospective cohort analysis of 11,306 children using and 21,192 children not using RMES [propensity matched by age and complex chronic conditions (CCC)] who were age 0-to-21 years and continuously enrolled in Medicaid in 2013 from 10 states in the Truven Health Medicaid MarketScan Database. RMES use at home (not counting acute use in a clinic, emergency department, or hospital) was identified with Healthcare Common Procedure Coding System (HCPCS), billed by medical supply companies, and International Classification of Diseases (ICD9) codes, billed by clinicians and hospitals. RMES included oxygen, suctioning, apnea monitor, CPAP/BiPAP, tracheostomy, ventilator, cough assist, and vest. We regressed RMES use on total annual per member per year (PMPY) Medicaid payments, adjusting for enrollment reason, gender, age, race/ethnicity, and number of chronic conditions. RESULTS: Of children using RMES at home, 5% were identified with ICD9 only, 80% with HCPCS only, and 15% with ICD9 and HCPCS. Most (87%) children using RMES had a chronic condition (of any complexity); 71% had a complex chronic condition. Neuromuscular (32%) was the most common CCC. RMES usage among children included oxygen (47%), suctioning (28%), apnea monitor (23%), CPAP/BiPAP (22%), tracheostomy (17%), ventilator (8%), cough assist (5%), and vest (4%). PMPY payments in propensity-matched children using vs. not using RMES were $45,892 vs. $15,036, p<0.001. In adjusted analysis, payment increased significantly (p<.001) with use of CPAP/BiPAP (+$1,117), oxygen (+$3,525), cough assist (+$6,342), suctioning (+$8,569), tracheostomy (+$11,977), vest (+$11,999), apnea monitor (+$13,747), and ventilator (+$32,323). Of children using RMES, most payments were for hospitalization (57%), specialty care (24%), and medications (6%); <3% was for RMES or home nursing. CONCLUSION: RMES use can identify additional projected healthcare costs in children beyond consideration of chronic diagnoses. Because most of the cost of using RMES is due to inpatient and specialty care rather than the equipment itself, RMES may indicate – broadly - medical fragility and increased healthcare needs. Population health initiatives of children with medical complexity may benefit from consideration of RMES use in risk assessment for healthcare cost.