Motion compensation
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This paper presents a system for correcting motion influences in time-dependent 2D contrast-enhanced ultrasound (CEUS) images to assess tissue perfusion characteristics. The system consists of a semi-automatic frame selection method to find images with out-of-plane motion as well as a method for automatic motion compensation. Translational and non-rigid motion compensation is applied by introducing a temporal continuity assumption. A study consisting of 40 clinical datasets was conducted to compare the perfusion with simulated perfusion using pharmacokinetic modeling. Overall, the proposed approach decreased the mean average difference between the measured perfusion and the pharmacokinetic model estimation. It was non-inferior for three out of four patient cohorts to a manual approach and reduced the analysis time by 41% compared to manual processing.
- MeSH
- břicho ultrasonografie MeSH
- Crohnova nemoc ultrasonografie MeSH
- cystická fibróza ultrasonografie MeSH
- databáze faktografické * MeSH
- interpretace obrazu počítačem metody MeSH
- kontrastní látky aplikace a dávkování MeSH
- lidé MeSH
- pohyb těles MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The compensation of cell motion is an important step in single-particle tracking analysis of live cells. This step is required in most of the cases, since the movement of subcellular foci is superimposed by the movement and deformation of the cell, while only the local motion of the foci is important to be analysed. The cell motion and deformation compensation is usually performed by means of image registration. There are a number of approaches with different models and properties presented in the literature that perform cell image registration. However, the evaluation of the registration approach quality on real data is a tricky problem due to the fact that some stable features in the images with a priori no local motion are needed. In this paper we propose a methodology for creating live cell nuclei image sequences with stable features imposed. The features are defined using the regions of fluorescence bleaching invoked by the UV laser. Data with different deformations are acquired and can be used for evaluation of the cell image registration methods. Along with that, we describe an image analysis technique and a metric that can characterize the quality of the method quantitatively. The proposed methodology allows building a ground truth dataset for testing and thoroughly evaluating cell image registration methods.
Práca prezentuje čiastkovú úlohu, ktorú sme realizovali v školskom roku 2009/2010 so žiakmi druhého stupňa základnej školy. Výsledky dokumentujú, že pomocou kompenzačných cvičení je možné pozitívne vplývať na zmeny funkčnosti posturálnych svalov. Vplyv experimentálneho činiteľa po dobu 8 mesiacov mal pozitívny účinok a bol štatisticky významný rovnako u dievčat, ako aj u chlapcov. Štatisticky významné na 5 % hladine významnosti boli aj zmeny v čase (medzi vstupnými a výstupnými testami) u chlapcov a dievčat. Rovnako u chlapcov i dievčat sme zaznamenali najčastejší výskyt skrátených svalov pri vstupných (aj výstupných) meraniach pri flexoroch kolenného kĺbu. Celkovo lepšie zmeny funkčnosti posturálnych svalov dosiahli dievčatá, ale chlapci zaznamenali väčšie rozdiely priemerov medzi vstupnými a výstupnými testami. Uvedená práca nadväzuje na prácu v Studii Kinanthropologia Vol 11, No 1, 2010.
The work represents a partial task, which we worked on during the school year 2009/2010 with the students of 2nd level basic schools. The results show that with the help of compensation exercises, it is possible to positively influence the function of postural muscles. The influence of the experimental subject during 8 months had a positive influence and was statistically important equally in boys and girls. Statistically important on 5% were also changes in time (between preliminary and final tests) in boys and girls. We also found that the most frequent shortening of muscles was in the flexor of the knee joint. This was found to be equal in boys and girls (even in final testing). As a whole, girls achieved better changes in the function of postural muscles; however boys achieved bigger differences between preliminary and final tests. This study supplements the partial work published in the work Kinanthropologia, Vol 11, No 1, 2010.
V predkladanom výskume sme sa zaoberali vplyvom kompenzačných cvičení aplikovaných počas telesnej výchovy na zmeny v svalovej nerovnováhe a zmeny v pohybovej výkonnosti. Súbor tvorilo 49 žiakov 1. ročníka strednej školy vo veku od 15 do 16 rokov. Triedy boli rozdelené na experimentálny a kontrolný súbor. Žiakov sme vyšetrili funkčnými testami na skrátené a oslabené svaly a porušené pohybové stereotypy. Súčasťou testovania boli aj testy pohybových schopností. Vstupným meraním sme zaznamenali vysoký výskyt (94%) svalovej nerovnováhy v celom súbore žiakov. Experimentálny činiteľ – kompenzačné cvičenia boli zaradené do hodín školskej telesnej a športovej výchovy v experimentálnej skupine po dobu 9 mesiacov. Kompenzačné cvičenia boli tvorené hlavne strečingovými cvičeniami, cvičeniami na aktiváciu a posilnenie svalov telesného jadra, stabilizačnými cvičeniami. Súčasťou experimentálneho činiteľa boli aj teoretické bloky. Vo výstupnom meraní sme v kontrolnej skupine nezaznamenali štatistické zmeny v jednotlivých zložkách svalovej nerovnováhy. V experimentálnej skupine došlo k štatisticky význam ným zmenám (p<0,01), (p<0,05) vo väčšine prípadov a kompenzačné cvičenia mali významný vplyv na zníženi incidencie jednotlivých porúch. Kompenzačné cvičenia mali vplyv aj na zvýšenie pohybovej výkonnost v experimentálnej skupine.
The aim of this work was to study the impact of compensation exercises applied during the classes of physical education on the changes in muscle imbalance and on the changes in movement performance. The research file was comprised of 49 students of the freshman year of high school aged 15 to 16 years. The classes were divided into an experimental and a control file. The students were examined by functional tests aimed at the identification of shortened and weakened muscles and abnormal motion stereotypes. The examination included tests of motion capabilities as well. By means of input measurements we have observed a high frequency of muscle imbalance (94%) in the entire file of students. An experimental element – the compensational exercises were incorporated into the physical education classes of the experimental file for a time period of 9 months. The compensation exercises consisted mainly of stretching exercises, exercises aimed at the activation and strengthening of the core muscles, stabilizing exercises. The experimental element also included theoretical blocks. We have not observed statistic changes in the individual parts of muscle imbalance in the output measurements of thecontrol file. Statistically significant changes (p<0,01), (p<0,05) occurred in the experimental file in majority of cases and compensation exercises had a great impact on the decreasing of incidence of he individual disorders. Compensation exercises influenced the increasing of movement performance in the experimental file as well.
AIMS: The main purpose of this study was to determine the changes in kinematic parameters of ischemic stroke affected upper limbs, during simple functional activity, to determine the most relevant changes. METHODS: The OptiTrack system was used for motion capture. To determine upper extremity function in Activities of Daily Living (ADL) tasks. During particular phases, the following matrices were chosen: mean and peak speed, normalized movement unit, normalized jerk and phase movement time. The chosen matrices represent the speed and smoothness profile of end-point data. The the arm-trunk compensation was also taken into consideration. Twenty stroke patients, in early (G1 from 1 to 3 months after stroke) and chronic stage (G2 from 6 months to 1 year), were studied. The large and small cylinder forward and back transporting phases were evaluated. RESULTS: The most significant differences between groups G1 and G2 were in mean and peak speed of the forward transport of the large and small cylinders for the paretic limb. Significant differences were also found for the smoothness (measured by movement unit, mean and peak speed and jerk) where the G2 group had a rougher motion. There were also differences in arm-trunk compensation in the frontal plane. CONCLUSION: The variables used in the study showed applicability in assessing kinematic parameters in both the early and chronic period after stroke.
- MeSH
- biomechanika MeSH
- cévní mozková příhoda patologie MeSH
- horní končetina inervace patofyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- rehabilitace po cévní mozkové příhodě * MeSH
- senioři MeSH
- snímání pohybu * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Domácí prostředí sehrává významnou roli v udržení soběstačnosti seniora po co nejdelší dobu. Hlavní význam pro zachování soběstačnosti je kladen na uchování pohybu a psychosociálního rozvoje osobnosti. Není-li jedinec schopen z různých důvodů zvládat běžné aktivity denního života a naplňovat své základní potřeby v domácím prostředí, stává se jedincem nesoběstačným, až závislým na okolí. Nezbytné je co nejrychlejší odhalení nebo předcházení tohoto stavu a zajištění takové péče, která bude vyhovovat konkrétní osobě a umožní jí vést co nejkvalitnější život v domácím prostředí či v prostředí, nejvhodnějším vzhledem k jeho zdravotnímu stavu.
Home environment is important element of keeping self sufficiency of senior as long aspossible. To the most significant moments in maintaining self sufficiency belongs keeping motion ability and psychosocial development of personality. If an individual is not able to manage common activities of everyday life and satisfy his basic needs in home environment for any reasons, he becomes self insufficient or even dependent. Detection at an early phase or prevention such a state, providing care which corresponds with particular needs and enables high-quality life in home environment or in environment most appropriate considering one’s health condition, is essential.
During radiotherapy treatment for thoracic and abdomen cancers, for example, lung cancers, respiratory motion moves the target tumor and thus badly affects the accuracy of radiation dose delivery into the target. A real-time image-guided technique can be used to monitor such lung tumor motion for accurate dose delivery, but the system latency up to several hundred milliseconds for repositioning the radiation beam also affects the accuracy. In order to compensate the latency, neural network prediction technique with real-time retraining can be used. We have investigated real-time prediction of 3D time series of lung tumor motion on a classical linear model, perceptron model, and on a class of higher-order neural network model that has more attractive attributes regarding its optimization convergence and computational efficiency. The implemented static feed-forward neural architectures are compared when using gradient descent adaptation and primarily the Levenberg-Marquardt batch algorithm as the ones of the most common and most comprehensible learning algorithms. The proposed technique resulted in fast real-time retraining, so the total computational time on a PC platform was equal to or even less than the real treatment time. For one-second prediction horizon, the proposed techniques achieved accuracy less than one millimeter of 3D mean absolute error in one hundred seconds of total treatment time.
- MeSH
- biologické modely * MeSH
- lidé MeSH
- mechanika dýchání * MeSH
- nádory plic patologie patofyziologie radioterapie MeSH
- neuronové sítě * MeSH
- pohyb těles * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- bederní obratle MeSH
- lidé MeSH
- muskuloskeletální nemoci * MeSH
- nádory periferního nervového systému MeSH
- nemoci páteře MeSH
- nemoci z povolání * diagnóza klasifikace prevence a kontrola MeSH
- odškodnění pracovníků MeSH
- poranění z opakovaného přetěžování MeSH
- posuzování pracovní neschopnosti MeSH
- rizikové faktory MeSH
- vibrace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
PURPOSE OF THE STUDY The number of patients with total hip arthroplasty (THA) has been growing. In addition to traumatic indication, the patients manifest abnormalities in kinematics and kinetics of gait preoperatively. The aim of the study was to assess kinematics of the pelvis and lower limbs during walking in patients with unilateral primary and revision THA. MATERIAL AND METHODS A total of 18 patients (10 females, 8 males) with primary THA (pTHA) as well as 18 patients (9 males, 9 females) with revision THA (rTHA) participated in the study. The control group (CON) comprised 19 healthy subjects (11 females, 8 males). Kinematic data were collected using the optoelectronic motion system Vicon MX. Kinematic parameters were obtained by means of 16 reflective markers placed on the patient's body in correspondence with the Plug-in Gait model. All the patients also underwent a clinical examination (evaluation of the surgery result, patient's satisfaction assessment, Harris score evaluation) and a specific X-ray evaluation of both hips. RESULTS The analysis brought the following results: - non-operated limb (NL) in pTHA vs. rTHA: significantly smaller total range of motion (ROM) in the hip joint (36.4° vs 41.7°) in the sagittal plane, - operated limb (OL) in pTHA vs. rTHA: significantly greater values of maximum knee flexion (14.2° vs. 9.8°) and extension (7.9° vs. 4.0°), - NL in pTHA vs. CON: significantly smaller ROM in the knee (51.0° vs. 57.9°) and hip (36.4° vs. 43.6°) joints in the sagittal plane, - OL in pTHA vs. CON: significantly smaller knee flexion (52.9° vs. 57.6°), hip extension (-0.6° vs. -10.4°), and the total ROM in the knee (51.5° vs. 57.9°) and hip (34.5° vs. 43.6°) joints in the sagittal plane, - NL in rTHA vs. CON: significantly greater pelvis ROM in both the sagittal (5.6° vs. 3.1°) and transverse (12.1° vs. 9.9°) planes, - OL in rTHA vs. CON: significantly smaller total ROM in the knee (48.9° vs. 57.9°) and hip (31.4° vs. 43.6°) joints in the sagittal plane. DISCUSSION After THA surgery, various gait pathologies as well as compensatory mechanisms can develop and chain; therefore, a complex approach to physical therapy in THA patients is needed. The number of significant differences found in kinematic parameters between pTHA and rTHA was low a year after the surgery. Compared to CON, both the THA groups exhibited similar mechanisms causing worsening their gait dynamics. CONCLUSIONS Gait in both the THA groups was characterized by a decreased ROM in the knee and hip joints in the sagittal plane, compensated by increased pelvic anteversion. Approximately one year after THA surgery, the NL is still noticeably dominant in gait. The changes in lower limb mechanics after revision THA persist even after a considerable time since the surgery. Key words: primary total hip arthroplasty, revision total hip arthroplasty, gait, range of motion, pelvic kinematics, biomechanics.
