Academic literature on the topic 'Ultrasound trigger'
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Journal articles on the topic "Ultrasound trigger"
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Chim, David, and Peter H. Cheng. "Ultrasound-guided trigger point injections." Techniques in Regional Anesthesia and Pain Management 13, no. 3 (July 2009): 179–83. http://dx.doi.org/10.1053/j.trap.2009.07.006.
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Tanaka, S., T. Ioka, R. Takakura, T. Sugiyama, and I. Akamatu. "Multistep trigger method for dynamic ultrasound." Ultrasound in Medicine & Biology 29, no. 5 (May 2003): S169—S170. http://dx.doi.org/10.1016/s0301-5629(03)00675-6.
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Cegla, Frederic. "Microwaves trigger thermo-acoustic ultrasound generation." Advanced Photonics 2, no. 03 (June 4, 2020): 1. http://dx.doi.org/10.1117/1.ap.2.3.030501.
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Brekke, Svein, and Hans Garmann Torp. "Trigger extraction from ultrasound doppler signals." Journal of the Acoustical Society of America 123, no. 2 (2008): 598. http://dx.doi.org/10.1121/1.2857724.
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Finlayson, Roderick J. "Ultrasound Guidance for Trigger Point Injections." Regional Anesthesia and Pain Medicine 42, no. 3 (2017): 279–80. http://dx.doi.org/10.1097/aap.0000000000000599.
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Botwin, Kenneth P. "Ultrasound-Guided Trigger Point Injections in the Cervicothoracic Musculature: A New and Unreported Technique." December 2008 6;11, no. 12;6 (December 14, 2008): 885–89. http://dx.doi.org/10.36076/ppj.2008/11/885.
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Background: Myofascial pain is defined as pain that originates from myofascial trigger points in skeletal muscle. It is prevalent in regional musculoskeletal pain syndromes, either alone or in combination with other pain generators. The myofascial pain syndrome is one of the largest groups of under diagnosed and under treated medical problems encountered in clinical practice. Trigger points are commonly seen in patients with myofascial pain which is responsible for localized pain in the affected muscles as well as referred pain patterns. Correct needle placement in a myofascial trigger point is vital to prevent complications and improve efficacy of the trigger point injection to help reduce or relieve myofascial pain. In obese patients, these injections may not reach the target tissue. In the cervicothoracic spine, a misguided or misplaced injection can result in a pneumothorax. Here, we describe an ultrasound-guided trigger point injection technique to avoid this potential pitfall. Office based ultrasound-guided injection techniques for musculoskeletal disorders have been described in the literature with regard to tendon, bursa, cystic, and joint pathologies. For the interventionalist, utilizing ultrasound yields multiple advantages technically and practically, including observation of needle placement in real-time, ability to perform dynamic studies, the possibility of diagnosing musculoskeletal pathologies, avoidance of radiation exposure, reduced overall cost, and portability of equipment within the office setting. To our knowledge, the use of ultrasound guidance in performing trigger point injection in the cervicothoracic area, particularly in obese patients, has not been previously reported. Methods: A palpable trigger point in the cervicothoracic musculature was localized and marked by indenting the skin with the tip of a plastic needle cover. The skin was then sterile prepped. Then, using an ultrasound machine with sterile coupling gel and a sterile latex free transducer cover, the musculature in the cervicothoracic spine where the palpable trigger point was detected was visualized. Then utilizing direct live ultrasound guidance, a 25-gauge 1.5 inch needle connected to a 3 mL syringe was placed into the muscle at the exact location of the presumed trigger point. This guidance helps confirm needle placement in muscle tissue and not in an adipose tissue or any other non-musculature structure. Results: The technique is simple to be performed by a pain management specialist who has ultrasound system training. Conclusion: Ultrasound-guided trigger point injections may help confirm proper needle placement within the cervicothoracic musculature. The use of ultrasound-guided trigger point injections in the cervicothoracic musculature may also reduce the potential for a pneumothorax by an improperly placed injection. Key words: Trigger point injection, myofascial pain, ultrasound
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Kumbhare, Dinesh A., Alyaa H. Elzibak, and Michael D. Noseworthy. "Assessment of Myofascial Trigger Points Using Ultrasound." American Journal of Physical Medicine & Rehabilitation 95, no. 1 (January 2016): 72–80. http://dx.doi.org/10.1097/phm.0000000000000376.
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Verma, Maneesh, Clifford L. Craig, Michael A. DiPietro, Jeff Crawford, Kelly L. VanderHave, Frances A. Farley, and Michelle S. Caird. "Serial Ultrasound Evaluation of Pediatric Trigger Thumb." Journal of Pediatric Orthopaedics 33, no. 3 (2013): 309–13. http://dx.doi.org/10.1097/bpo.0b013e318287f728.
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Salleo, Sebastiano, Patrizia Trifilò, and Maria Assunta Lo Gullo. "Vessel wall vibrations: trigger for embolism repair?" Functional Plant Biology 35, no. 4 (2008): 289. http://dx.doi.org/10.1071/fp07239.
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Xylem embolism repair is preceded by starch depolymerisation in vessel-associated cells (VAC) of Laurus nobilis L. (laurel) twigs, but the primary signal triggering such a process is still unknown. We tested the hypothesis that conduit wall vibrations during cavitation may be sensed by VAC inducing starch-to-sugar conversion. Twigs of laurel from watered or stressed plants were exposed to ultrasound for 60 min to simulate acoustic waves emitted by cavitating conduits. Preliminary tests showed that ultrasound caused no damage to cell membrane integrity nor did they cause xylem embolism. The number of VAC with high starch content (HSC-cells) was estimated microscopically by counting the cells with more than 50% of their lumen filled with starch granules. Sonication had no effect on HSC-cells in twigs from watered plants while it induced a drop in the percentage HSC-cells from 80 to 40% in twigs from stressed plants, at the ultrasound source location. No effect was recorded in these twigs 20 mm from the ultrasound source. Sonication was a good simulator of cavitation in inducing starch depolymerisation which suggests a possible bio- physical nature for the signal initiating embolism repair.
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Prasad, Shiva, Vijay LNU, Gururaj Bangari, Priyanka Patil, and Spurti N. Sagar. "Ultrasound Guided Trigger Point Injections in Myofascial Pain Syndrome." Indian Journal of Physical Medicine and Rehabilitation 26, no. 3 (2015): 82–84. http://dx.doi.org/10.5005/ijopmr-26-3-82.
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Abstract Trigger points as a cause of musculoskeletal or myofascial pain syndrome is well documented. Trigger points (Tr Ps) are tender and hypersensitive nodules seen in skeletal muscles which develop as a result of sudden or repetitive trauma to the muscles. They cause contractile state of a muscle with local or radiating pain. Active trigger points cause intense pain with limitation of movements of the muscles. The treatment involves deactivating the trigger points, usually done by various methods. Most common practice is myotherapy which involves deep tissue massage which is painful and time consuming. Dry needling and needling with anaesthetic injaection have been successfully used by many. Recently, ultrasound guidance is used to locate the trigger points and to accurately place the needle in to them to deactivate, thus preventing complications of blind procedures.
Dissertations / Theses on the topic "Ultrasound trigger"
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Bethers, Amber Hancock. "Positional Release Therapy Versus Therapeutic Massage in Reducing Muscle Trigger and Tender Points." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7256.
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Objective: To determine the difference in effectiveness of positional release therapy (PRT) compared with therapeutic massage (TM) in treating trigger and tender points in the upper trapezius muscle. Background: Trigger points in the upper trapezius muscle are common and can be painful. Therapeutic massage is a more traditional treatment method for this condition while PRT is relatively new. Design and Setting: A randomized-group design was used to examine the differences between the 2 treatments for reducing pain and muscle tension. Subjects: Sixty healthy subjects (males = 24, females = 36; age = 27.1 ± 8.8 years; wt = 75.2 ± 17.9 kg; ht = 172.8 ± 9.7 cm) presenting with upper trapezius pain and a trigger point. Subjects were randomly assigned to the TM group or the PRT group. Measurements: Presence of upper trapezius trigger points was found via palpation by a clinician. Level of pain was measured by a visual analog scale (VAS) and pain pressure threshold (PPT) was assessed by a pressure algometer. Muscle thickness was measured by B-mode ultrasound (US) and muscle tension was measured by shear-wave elastography (SWE). Subjects were measured pretreatment and posttreatment and 48 hours later. Results: All measurements showed significant improvements for both treatments. Positional release therapy was more effective (p = 0.05) at reducing pain at day 2 and was able to maintain the pain loss. The SWE and US showed no difference between the treatment groups. There was no significant difference in PPT, but PRT PPT increased each visit while TM dropped significantly at day 2 (p = .003). Conclusion: Both treatments showed a significant ability to reduce pain and acutely decrease muscle stiffness (as measured by SWE) but there were few differences between the treatments. However, there appeared to be a slight benefit for pain reduction with PRT up to 2 days posttreatment.
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Meirim, Cindy Mariel Gonçalves. "Avaliação da dor dos trigger points do trapézio superior em pacientes submetidos ao ultrassom combinado com aloé vera." Bachelor's thesis, [s.n.], 2018. http://hdl.handle.net/10284/7018.
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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciada em FisioterapiaObjetivo: avaliar a dor dos trigger points latentes do trapézio superior em indivíduos submetidos a ultrassom (US) com aloé vera ou com gel comum. Metodologia: 24 indivíduos, com uma média de idades 23,44 anos, foram distribuídos de forma aleatória em dois grupos e que devido a 8 desistências, 7 ficaram no grupo US com gel comum (grupo 1) e 9 no grupo US com gel de aloé vera (grupo 2). Os US’s foram aplicados bilateralmente nos trigger points latentes do trapézio superior, durante 10 sessões, em 2 semanas. Foi avaliada a intensidade álgica, através da escala numérica da dor (END) e o limiar de dor através do algómetro, antes da 1ª sessão, depois da 5ª e depois da 10ª. Resultados: O grupo 1 teve diminuição significativa da dor, em ambos os trapézios, com a END, entre todos os momentos de avaliação mas apenas aumento significativo no limiar de dor no trapézio direito entre a 1ª e última avaliação. O grupo 2, quer na END quer no limiar teve melhorias significativas a partir da 5ª sessão em ambos os trapézios. No entanto, em nenhum momento, houve diferenças entre grupos. Conclusão: As duas técnicas testadas apresentaram-se eficazes na diminuição da perceção de intensidade da dor e o aloé vera contribuiu mais para o aumento de tolerância ao limiar de dor em ambos os lados do trapézio superior.
Purpose: To evaluate the pain of the latent trigger points of the upper trapezius, on individuals submitted with an ultrasound (US) treatment with aloe vera or with common gel. Methods: 24 individuals, with an average of ages of 23,44 years, where randomly assigned into two groups, but due to 8 withdrawals, 7 stayed in the group using the common gel (group 1) and 9 in the group US using aloe vera (group 2),. US’s were applied bilaterally on the latent trigger points of the upper trapezius, throughout 10 sessions, in the space of 2 weeks. The pain intensity was evaluated, using a numeric pain scale (NPS) and the pain threshold using a pressure algometer before the first session and after the 5th and the 10th session. Results: Group 1 had a significant diminish of pain, of both trapezius, with NPS, but a higher pain threshold of the right trapezius between the first and last evaluation. In group 2, only from the 5th session that significant enhancements where observed with NPS and by the threshold, on both trapezius. However, at no point there were differences between groups. Conclusion: The two techniques that we tested were effective for diminishing the perception of the pain intensiveness, and aloe vera contributed for a higher tolerance of the pain threshold on both sides of the upper trapezius.
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Müller, Cristina Emöke Erika 1978. "Avaliação de pontos-gatilho miofasciais por imagens de ultrassom e elastografia ultrassonográfica em mulheres tratadas pela acupuntura, eletroacupuntura e acupuntura sham : estudo piloto = Two-dimensional ultrasound and ultrasound elastography imaging of myofascial trigger points in women treated by acupuncture, electroacupuncture and sham acupuncture : pilot study." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287942.
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Orientador: Maria Beatriz Duarte GaviãoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-24T16:50:05Z (GMT). No. of bitstreams: 1 Muller_CristinaEmokeErika_M.pdf: 2322583 bytes, checksum: 34487fb1a63db95bab0032e52585a63e (MD5) Previous issue date: 2014
Resumo: O presente estudo, de caráter experimental, teve como objetivo a avaliação de pontos-gatilho miofasciais (PG) do músculo trapézio descendente (TPz) por imagens de ultrassonografia bidimensional em escala de cinza (US 2D) e elastografia ultrassonográfica (ELASTO), bem como avaliar a eficácia das técnicas de acupuntura (AC) e eletroacupuntura (EA) na diminuição da dor em mulheres com síndrome da dor miofascial (SDM) associada a queixas de dor nas regiões de cabeça, pescoço e parte superior do tronco. Uma amostra de conveniência de 24 voluntárias, com idades entre 20 e 40 anos (27,33±5,05), IMC entre 18,03 e 27,09 Kg/m² (22,59±3,11), ciclo menstrual regular, presença de ao menos um PG ativo em ambos os TPz, queixa de dor local e/ ou referida há pelo menos seis meses foi selecionada para o estudo. Após a assinatura do Termo de Consentimento Livre e Esclarecido (TCLE), as voluntárias foram randomizadas em três grupos, sendo: dois grupos de tratamento (AC e EA) e um grupo controle (SHAM). Oito sessões de tratamento foram então realizadas, duas vezes por semana, durante aproximadamente um mês, levando em consideração o ciclo menstrual das voluntárias. Imagens do músculo trapézio foram adquiridas pelas técnicas de US 2D e ELASTO para avaliação e diagnóstico das propriedades mecânicas e viscoelásticas do tecido miofascial e a comparação dessas características pré e pós-tratamento. Nas imagens de US 2D, as áreas dos PG foram mensuradas. Nos elastogramas adquiridos pela ELASTO, o índice de resistência (IR) foi calculado. Tanto as voluntárias quanto o examinador eram cegos em relação aos grupos. A intensidade de dor geral e localizada nos TPz direito e esquerdo (TPzD e TPzE, respectivamente) pré e pós-tratamento foi mensurada com o auxílio da escala visual analógica (EVA). A ocorrência de fatores influenciadores e as fases do ciclo menstrual foram monitoradas. Os dados foram analisados quanto à normalidade e simetria. Na avaliação intragrupo todos os dados apresentaram distribuição normal, sendo analisados pelo teste t student para dados pareados. Observou-se diminuição da intensidade de dor geral para o grupo AC (P<0,001) e de dor geral e local para a EA (geral, P=0,027; TPzD, P<0,001; TPzE, P=0,005); sem resultados estatisticamente significantes para o grupo SHAM (geral, P=0,296; TPzD, P=0,052; TPzE, P=0,198). Quanto à avaliação de PG nas imagens de US 2D , observou-se diminuição da área do PG para ambos os TPzD e TPzE nos grupos AC (TPzD e TPzE, P<0,001) e EA (TPzD, P=0,003; TPzE, P=0,005); e não para o grupo SHAM (TPzD, P=0,117; TPzE, P=0,093). Em relação à ELASTO, os dados não apresentaram significância estatística para a amostra analisada, contudo, o IR de ambos os lados apresentou-se menor após o tratamento para a EA e AC, e maior para a SHAM. Na comparação entre grupos, diferenças estatisticamente significantes não foram observadas para as variáveis testadas. Os resultados do presente trabalho sugerem a possibilidade de utilização da US 2D e ELASTO na caracterização do tecido miofascial e de PG, apontando para a possibilidade de confirmação objetiva de efeitos subjetivos de tratamentos propostos para a SDM. Ainda, as técnicas de AC e EA demonstraram eficácia no alívio da dor geral, sendo a efetividade da EA observada também na diminuição da intensidade de dor local. O nível de significância adotado foi ?=0,05
Abstract: The aim of this study was to evaluate upper trapezius (TPz) myofascial trigger points (MTrP) through two-dimensional ultrasonography (2D US) and ultrasound elastography (ELASTO) images, as well as, to evaluate the effectiveness of acupuncture (AC) and electroacupuncuture (EA) in decreasing pain in women with myofascial pain syndrome (MPS) associated with head, neck and upper back complaints. A convenience sample of 24 volunteer aged between 20 and 40 years (27.33±5.05 years), body mass index (BMI) from 18.03 to 27.09Kg/m² (22.59±3.11), presenting regular menstrual cycle, at least one active MTrP at both right and left TPz (RTPz and LTPz, respectively) and local or referred pain for up to six months were selected. After signing the Informed Consent Form (ICF), subjects were randomized into three groups, being: two treatment groups (AC and EA) and one control group (SHAM). Eight treatment sessions were than performed, two times per week, for nearly one month, considering each volunteer menstrual cycle. Pre, post-treatment Intensity of pain was assessed by visual analogue scale (VAS) as well as MTrP mean area and strain ratio (SR) by 2D US and ELASTO, respectively, in way to myofascial tissue mechanical and viscoelastic properties assessment and diagnosis. Both, volunteers and examiner were blinded for the three groups. Influencing factors and menstrual cycle phases were monitored. Data were analyzed for normality and symmetry. All intragroup data were normally distributed, so, were analyzed by Student¿s t test for paired data. Decrease in pain intensity was observed for AC (general, P<0.001) and EA (general, P=0.027; RTPz, P<0.001; LTPz, P=0.005); without any significant result for SHAM (general, P=0.296; RTPz, P=0.052; LTPz, P=0.198). Decreased MTrPs area occurred for both sides in AC (RTPz and LTPz, P<0.001) and EA (RTPz, P=0.003; LTPz, P=0.005); on the other hand, SHAM results were not significant (RTPz, P=0.117; LTPz, P=0.093). Concerning ultrasound elastography, although not statistically significant, post-treatment SR in both sides were lower than the beginning for EA and AC, and higher for SHAM group. Regarding within group comparison, no statistically significant difference were observed for the tested variables. 2D US and ELASTO presented the possibility of MTrPs and surrounding tissue diagnosis and characterization, pointing to the possibility of objective confirmation of subjective MPS treatment effects. Also, EA and AC were effective in decreasing general pain intensity, being EA also effective in local pain intensity relief. The level of significance was ?=0.05
Mestrado
Anatomia
Mestra em Biologia Buco-Dental
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Graham, Susan M. "Ultrasound-triggered drug release from liposomes using nanoscale cavitation nuclei." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:510ab12d-74c9-4c07-a621-4dc388b14f7a.
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Side effects of current chemotherapeutics limit their use in cancer therapy. Although many current drugs are highly toxic and potent, the effects they have on non-cancerous tissue are unbearable for patients. Targeting these drugs may provide a means to restrict their toxic effects to only cancer tissue while leaving healthy tissue unaffected. This approach requires that the drug is only available in cancer tissue, which has been achieved here by encapsulating drugs into liposomal nano-capsules which are capable of passively accumulating in cancerous tissue via the enhanced permeability and retention effect (EPR). In addition to localisation, a threshold dose must be achieved to deliver the desired toxic effect to the target tumour tissue. Previous strategies have relied on passive 'leaching' of the drug from liposomes, however this 'leaching' does not necessarily achieve the threshold dose required. In the present work, a new generation of liposomes has been developed whereby release is solely achieved in the presence of ultrasound triggered cavitation. Instigation of such cavitation events would normally require the target tissue be exposed to high and possibly damaging ultrasound pressures. To remove the need for these high pressures, cavitation nuclei have been developed to lower the cavitation threshold of surrounding media. To allow for improved co-localisation and treatment deeper into cancer tissue, cavitation nuclei were developed to be in the nanoscale size range. Two types of novel cavitation nuclei were produced, a rough surfaced carbon nanoparticle (CNP, ~180 nm) and smooth shaped polymeric nano-cup particle (NC, ~150, 470, or 770 nm). Both types of particle are solid nanoparticles with gas entrapped on their surface which was capable of cavitating in response to ultrasound without greatly affecting the particle itself. These particles are classified as cavicatalytic nanoparticles due to their ability to reduce the cavitation threshold of their surrounding media without being destroyed themselves. Finally, an entirely nanoscale release system was developed and tested in vitro and in vivo. The drug carrier (the liposome) and effector agent (the cavicatalytic nanoparticle) were used to demonstrate ultrasound triggered drug release, specifically in response to the generation of cavitation events. These cavitation events could be non-invasively monitored and characterised, adding to the potential clinical utility of the technologies developed and described here.
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Alrifai, Nour. "Émulsion chargée en principe actifs permettant une libération contrôlée par ultrasons Ultrasound-triggered delivery of paclitaxel encapsulated in an emulsion at low acoustic pressures." Thesis, Sorbonne université, 2020. https://accesdistant.sorbonne-universite.fr/login?url=http://theses-intra.upmc.fr/modules/resources/download/theses/2020SORUS007.pdf.
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L'encapsulation de médicaments est un domaine florissant où les améliorations thérapeutiques potentielles sont importantes. À cet égard, la capacité de contrôler la libération du médicament à l´aide des ultrasons est séduisante car elle permet de localiser et gérer l´administration du médicament. Dans mon projet de thèse, j´ai étudié la possibilité d´utiliser de faibles intensités ultrasonores pour contrôler la libération du médicament. Pour ce faire, j´ai utilisé des émulsions pour encapsuler deux types de médicaments : le « paclitaxel », un médicament anticancéreux, et la « lévofloxacine », un antibiotique. Le paclitaxel a été encapsulé dans une émulsion composée de nanogouttelettes comprenant un noyau composé d´huile et de bromure de perfluorooctyle (PFOB) stabilisé par un tensioactif fluoré et biocompatible appelé Dendritac. La lévofloxacine a été encapsulé dans une émulsion composée uniquement des nanogouttelettes huileux, on a pu réduire la diffusion de la lévofloxacine hors de la gouttelette en ajoutant des esters de triglycérides. Nous avons étudié la délivrance déclenchée par ultrasons du paclitaxel en présence de lignée cellulaire de carcinome colorectal et du lévofloxacine en présence d’Escherichia coli. Nous avons montré que les ultrasons déclenchent la délivrance de médicaments pour des faibles pressions acoustiques (0.4 Mpa) lors de l´utilisation d´ultrasons à une fréquence de 1 MHz avec un rapport cyclique de 5% et une fréquence de répétition des impulsions de 200 HzDrug encapsulation is a thriving area where potential therapeutic improvements are important. In this regard, the ability to control drug release using ultrasound is attractive because it helps to locate and manage drug delivery. In my thesis project, I studied the possibility of using low ultrasonic intensities to control drug release. To do this, I used emulsions to encapsulate two types of drugs: "paclitaxel", an anticancer drug, and "levofloxacin", an antibiotic. Paclitaxel was encapsulated in an emulsion composed of nanodroplets comprising a core composed of oil and perfluorooctyl bromide (PFOB) stabilized by a fluorinated and biocompatible surfactant called Dendritac. Levofloxacin was encapsulated in an emulsion composed only of oily nanodroplets; we were able to reduce the diffusion of levofloxacin out of the droplet by adding esters of triglycerides. We investigated the ultrasound-triggered delivery of paclitaxel in the presence of a colorectal carcinoma cell line and levofloxacin in the presence of Escherichia coli. We have shown that ultrasound triggers the delivery of drugs for low sound pressures (0.4 Mpa) when using ultrasound at a frequency of 1 MHz with a duty cycle of 5% and a pulse repetition frequency of 200 Hz
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Kopechek, Jonathan A. "The Role of Acoustic Cavitation in Ultrasound-triggered Drug Release from Echogenic Liposomes." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1318878799.
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Ta, Terence. "PH/thermosensitive liposomes modified with poly(N-isopropylacrylamide-co-propylacrylic acid) copolymers for focused ultrasound-triggered release of Doxorubicin." Thesis, Boston University, 2012. https://hdl.handle.net/2144/31615.
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Thesis (Ph.D.)--Boston UniversityPLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Chemotherapy requires the systemic administration of large doses of highly toxic antineoplastic agents in order to achieve therapeutically relevant concentrations at the tumor. These drugs typically act by impairing cell mitosis, effectively targeting rapidly-dividing cells that are the hallmarks of cancer. Non-cancerous cells that divide rapidly under normal circumstances are often damaged, leading to adverse side effects including myelosuppression, alopecia, and organ-specific toxicities. One potential means of reducing off-site toxicities is to encapsulate highly toxic chemotherapeutics into thermosensitive liposomes (TSL). These nanoscale structures are formed from temperature-sensitive lipids, and are designed to passively target the tumor by being large enough to avoid renal clearance while small enough to slip through leaky blood vessels characteristic of tumor vasculature. At the tumor, externally applied heating triggers a burst release of therapeutically relevant concentrations of drug. Current TSL formulations suffer from (i) approaches for heating that put healthy tissue surrounding the tumor at risk; (ii) lack of stability at physiological conditions (e.g. premature leakage of drug); and (iii) lack of noninvasive approaches for monitoring temperature elevation. This project presents a dual pH/thermosensitive liposome (PTSL) for the deliver of Doxorubicin (DOX), a commonly administered chemotherapeutic. Copolymers of temperature-responsive N-isopropylacrylamide (NIPAAm) and pH-responsive propylacrylic acid (PAA) were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, yielding copolymers with dual pH/temperaturedependent phase transition properties. When attached to liposomes, copolymers were membrane-disruptive m a pH/temperature-dependent manner, conferring pH/temperature-sensitive drug release properties to the liposome. These dual-sensitive properties can potentially exploit the slightly acidic environment of the tumor when PTSL are administered with externally applied heating. PTSL demonstrated enhanced release profile, significantly lower thermal dose threshold, and lower IC50 when compared to traditional TSL, and were stable in serum with minimal premature drug leakage. The application of MR-guided focused ultrasound (MRgFUS) as a noninvasive, highly controllable thermal source for triggering drug release and monitoring temperature elevations was demonstrated in vivo. PTSL combined with MRgFUS treatment resulted in delayed tumor growth when compared to PTSL alone and control treatments. This PTSL-MRgFUS delivery system thus addresses the limitations of existing TSL therapies and has potential applications in the clinic.
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Chernukha, Yevheniia. "Investigation of phase transitions triggered by laser-induced focusing shock waves." Thesis, Le Mans, 2019. http://www.theses.fr/2019LEMA1038.
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La capacité de certains matériaux à changer d'état fondamental sous excitation laser a ouvert un champ de recherche autour de la manipulation de leurs propriétés par la lumière. Les processus chimiques et physiques mis alors en jeu sont riches et complexes. Dans ce contexte, le rôle prédominant de la coopérativité élastique pour l’amplification et la stabilisation de la transition a été mis en évidence récemment dans un matériau à transitions de spin irradié par laser. Ces observations font apparaître la perspective de commuter de façon permanente certaines propriétés des matériaux par des ultrasons non-linéaires, des ondes de choc excitées par laser.Dans un premier temps, nous introduisons le dispositif expérimental d’imagerie mono-coup résolu en temps, associée à la technique de focalisation des ondes de chocs excitées par laser au niveau de la surface de l’échantillon. La séparation spatiale des régions irradiées par le laser et influencées par les ondes de choc propagatives permet de discerner clairement les changements du matériaux induits uniquement par les ondes de choc. Dans un second temps, nous présentons nos résultats expérimentaux en lien avec cette technique innovante, aux matériaux dont les changements de phases impliquent un changement de volume macroscopique (systèmes spin-crossover, isolants de Mott). Des analyses post-mortem des échantillons ont permis de confirmer, dans certaines conditions expérimentales, une modification permanente de la phase du matériau par action de l'onde de choc. Ces résultats ouvrent des perspectives pour la généralisation à de nombreux matériaux du phénomène de coopérativité élastique donnant lieu à des transition permanentThe ability of certain materials to change its ground state due to laser excitation has arisen a lot of opportunities for light-control of material properties. The field of photo-induced phase transitions counts a rich variety of chemical and physical processes triggered by light-matter interactions involved during the phase transition process. Recently it was reported that elastically driven cooperativity leads to the amplification of spin state in molecular crystals and prolonged the lifetime of the transient state with an ultra-short laser pulse. The cooperative response appears during the propagation of non-linear coherent strain waves, in other words shock waves, coupled with the order parameter field. Shock waves can be seen as a new challenging pathway to achieve a permanently switched state with appropriate excitations.First, we introduce time-resolved single-shot imaging combined with the laser shock focusing technique that makes it possible to generate, acoustically focus, and directly visualize under a microscope shock waves propagating and focusing along the sample surface. The spatial separation of the laser-influenced and strain-influenced regions makes it possible to disentangle the material changes produced solely by the shock waves. Second, we present experimental results involving the shock-focusing technique to materials undergoing phase transitions linked with a macroscopic change of their volume (spin-crossover systems, Mott insulators). Post-mortem analyses of the samples confirm permanent phase transition under specific experimental conditions. These innovative results open doors for a generic elastically driven cooperativity
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Al, Sabbagh Chantal. "Liposomes thermosensibles furtifs pour l'administration du 5-Fluorouracile déclenchée par ultrasons." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA114819/document.
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Nous avons optimisé des liposomes thermosensibles, encapsulant un principe actif anticancéreux, le 5-Fluorouracile (5-FU), afin de déclencher sa libération par une hyperthermie locale modérée (39-42°C) induite par des ultrasons focalisés. L'hyperthermie sera appliquée au niveau de la tumeur, afin d'améliorer l’efficacité thérapeutique et de réduire la toxicité systémique. Les liposomes ont été formulés par hydratation du film lipidique en mélangeant la 1,2-dipalmitoyl-sn-glycéro-3-phosphocholine (DPPC) pour sa thermosensibilité à 41,5 ± 0,5°C, le cholestérol (CHOL) pour favoriser la stabilité des liposomes vis-à-vis des composants du sang, et le 1,2-distéaroyl-sn-glycéro-3-phosphoéthanolamine-N-[méthoxy(polyéthylène glycol)-2000] (DSPE-PEG) pour assurer la furtivité de la formulation. Les expériences ont confirmé que les liposomes formulés à base de DPPC/CHOL/DSPE-PEG dans un ratio molaire 90 : 5 : 5 mol% sont thermosensibles. Des liposomes composés du même mélange lipidique dans un rapport 65 : 30 : 5 mol% ont été considérés comme contrôle négatif non thermosensible. L’optimisation de l’encapsulation passive du 5-FU a permis d’obtenir une efficacité d’encapsulation (5-FU encapsulé/5-FU total) de 13%, mais le 5-FU est très faiblement retenu (12%) dans la cavité aqueuse des liposomes du fait du gradient osmotique à la dilution. La rétention du 5-FU a été optimisée (93%) par la technique d’encapsulation active basée sur la complexation intraliposomale du 5-FU avec le complexe cuivre-polyéthylèneimine préalablement encapsulé dans les liposomes. Cette technique a également permis d’améliorer l’efficacité d’encapsulation d’un facteur trois environ (37%), avec un taux de charge (ratio final 5-FU/lipides, mole/mole) de 50% environ. Nous avons alors obtenu des liposomes thermosensibles d'un diamètre hydrodynamique de 65 nm et de charge de surface de -10 mV. Les liposomes non thermosensibles, ont été caractérisés par un diamètre hydrodynamique de 105 nm et une charge de surface de -4,9 mV. La libération du 5-FU déclenchée par une hyperthermie induite par des ultrasons focalisés a été mesurée in vitro. En réponse à une hyperthermie de 42°C, les liposomes thermosensibles libèrent 68% de leur contenu, au bout de 10 min, alors que les liposomes non thermosensibles en libèrent moins de 20%. En outre, la cytotoxicité des liposomes encapsulant le complexe 5-FU-cuivre-polyéthylèneimine a été évaluée vis-à-vis de la lignée cellulaire HT-29 du carcinome colorectal humain. Les résultats ont révélé que les lipides à une concentration de 800 µM ne sont pas cytotoxiques (80% de viabilité). De plus, la complexation du 5-FU n’influence pas sa cytotoxicité ce qui prouve que la toxicité provient du 5-FU et non des excipients. En revanche, l’encapsulation du complexe 5-FU-cuivre-polyéthylèneimine dans les liposomes induit une diminution de la concentration inhibitrice médiane de 115 (solution du complexe) à 49 µM environ, corrélée à leur internalisation cellulaire. La pharmacocinétique chez des souris porteuses d’un modèle de tumeur colorectale HT-29 xénogreffée a montré que les liposomes permettent de prolonger d’un facteur 1,4 la demi-vie plasmatique de distribution du 5-FU. De plus, les aires sous la courbe des concentrations plasmatiques sur 24 h sont 1,9 et 2,9 fois plus élevées lorsque le 5-FU est administré sous forme de liposomes thermosensibles et non thermosensibles, respectivement, par rapport à la solution de 5-FU. Enfin, les liposomes non thermosensibles augmentent significativement d'un facteur 2 l'accumulation du 5-FU dans la tumeur par rapport à la solution de 5-FU. En conclusion, les liposomes thermosensibles développés présentent un fort intérêt pour une application thérapeutique en combinaison avec des ultrasons focalisésWe optimized thermosensitive liposomes encapsulating an anticancer drug, 5-Fluorouracil (5-FU), in order to trigger the release upon focused ultrasound-mediated mild hyperthermia at the tumor. This approach would improve drug efficacy and would lower side effects. Liposomes were prepared by the lipid hydration method by mixing 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) for its temperature sensitivity at 41.5 ± 0.5°C, cholesterol (CHOL) to promote liposome stability towards blood components, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG) to confer stealthiness to the formulation. The experiments confirmed that the liposomes formulated with DPPC/CHOL/DSPE-PEG in a molar ratio 90:5:5 mol% are thermosensitive, while liposomes composed of the same lipid mixture in a ratio 65:30:5 mol% were considered non thermosensitive negative control. The optimization of passive encapsulation of 5-FU yielded an encapsulation efficacy (encapsulated 5-FU/total 5-FU) of 13%. 5-FU was, however, very weakly retained (12%) in the aqueous core of liposomes following dilution due to the generation of an osmotic gradient. The retention of 5-FU has been optimized (93%) by the active encapsulation technique based on the intraliposomal complexation of 5FU with copper-polyethylenimine complex encapsulated beforehand into liposomes. This technique also improved 5-FU encapsulation efficacy by 3-fold (37%), yielding a loading efficiency (final drug/lipid ratio, mol/mol) of approximately 50%. The resulting thermosensitive liposomes and non thermosensitive liposomes have a hydrodynamic diameter and a surface charge around 65 nm and -10 mV, and 105 nm and -4.9 mV, respectively. Heat-triggered drug delivery was evaluated using focused ultrasound, and showed a release of 68% of the encapsulated 5-FU from thermosensitive liposomes, within 10 min, whereas release remained below 20% for the non thermosensitive formulation. Furthermore, the cytotoxicity of 5-FU-copper-polyethylenimine complex-loaded liposomes towards HT-29 human colorectal carcinoma cell line was evaluated. Results revealed that lipids at a concentration of 800 µM are not cytotoxic (80% viability). Moreover, 5-FU complexation has no impact on its cytotoxic activity, disclosing that liposomes toxicity arose from 5-FU and not from the excipients. Nevertheless, 5-FU-copper-polyethylenimine complex-loaded liposomes exhibited a lower half maximal inhibitory concentration of 49 µM compared to 115 µM for complex solution. This enhancement of cytotoxicity was attributed to the cellular internalization of liposomes. Pharmacokinetics in mice bearing HT-29 xenograft tumor showed that liposomes can extend the plasma distribution half-life of 5-FU by a factor 1.4. Furthermore, areas under the concentration-time curve over 24 h were higher by 1.9- and 2.9-fold when the drug was encapsulated into thermosensitive and non thermosensitive liposomes, respectively, compared to free 5-Fluorouracil. Finally, non thermosensitive liposomes significantly increased 5-FU accumulation in tumor by 2-fold, compared to 5-FU solution. In conclusion, these 5-FU-loaded thermosensitive liposomes represent valuable carriers to investigate the therapeutic efficacy following focused ultrasound-mediated heat application
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Ting-LiShen and 沈庭立. "Trigger Finger Surgical Training System with 3D Image Reconstruction from Orthogonal Ultrasound Images." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/8m7435.
Full textBooks on the topic "Ultrasound trigger"
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Bodor, Marko, Sean Colio, and Christopher Bonzon. Hand and Wrist Injections: Ultrasound. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199908004.003.0045.
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Two basic ultrasound-guided approaches are used for procedures to diagnose and treat chronic pain in the upper extremity. The short-axis approach is best for injections of superficial, vertically oriented joints, whereas the long-axis approach is best for relatively deep injections and more open joints or whenever it is necessary for the needle to be seen at all times. Ultrasound can guide injections for nerve compressions. Carpal tunnel syndrome is the most common peripheral nerve entrapment syndrome. Ulnar tunnel syndrome occurs in the setting of space-occupying lesions. Ultrasonography can identify a space-occupying lesion, while electrodiagnostic studies can help differentiate ulnar neuropathy at the wrist from ulnar neuropathy at the elbow. Ultrasound can also guide injections at joints such as the basilar join of the thumb, phalangeal joints, and wrist joints. Ultrasound-guided injections are also useful for tendon dysfunctions including de Quervain’s Tenosynovitis, trigger finger, intersection syndrome, and tendon impingement.
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Shankar, Hariharan, and Karan Johar. Piriformis Muscle, Psoas Muscle, and Quadratus Lumborum Muscle Injections: Ultrasound. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199908004.003.0047.
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This chapter describes the anatomy, technique, available evidence, and complications of piriformis, psoas, and quadratus lumborum muscle injections. Traditionally landmark-based injections of the piriformis muscle were performed using the posterior inferior iliac spine and the greater trochanter as bony landmarks. Subsequently, fluoroscopy, electromyography, and CT were used to facilitate the injection. Activation of myofascial trigger points within the iliopsoas muscle can cause referred pain to the groin and anterior thigh. Landmark-based injections and CT-guided iliopsoas injections have been described. But they carry the risk of radiation, bowel injury, intravascular injection, and nerve injury. Ultrasound-guided injection into the psoas muscle may be performed at two different locations, the iliopsoas muscle and the iliopsoas tendon. The quadratus lumborum is a common cause of low back pain, and ultrasound-guided injection of local anesthetic into quadratus lumborum muscle may be performed.
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Peterson, Martin. Are Technological Artifacts Mere Tools? Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190652265.003.0009.
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The geometric method rests heavily on the assumption that the aim of a moral analysis of technology is to determine what professional engineers, designers, and ordinary users ought to do when confronted with ethical issues triggered by new or existing technologies. Some scholars reject this assumption. According to an influential tradition, the central research question for a moral analysis of technology should be to establish what ethical values, norms, or other moral properties are embedded in technological artifacts qua artifacts. On this view guns, cars, and obstetric ultrasound scanners are no mere tools; they have moral properties of their own. This chapter discusses this artifact approach to the ethics of technology.
Book chapters on the topic "Ultrasound trigger"
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Callegari, Leonardo. "Treatment of Trigger Finger." In Ultrasound-guided Musculoskeletal Procedures, 113–18. Milano: Springer Milan, 2012. http://dx.doi.org/10.1007/978-88-470-2742-8_21.
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Nickl, Stephen, and Lauren M. Terranova. "Trigger Point Injections." In Atlas of Ultrasound Guided Musculoskeletal Injections, 89–99. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8936-8_8.
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Tortora, Mariarosaria, Letizia Oddo, Silvia Margheritelli, and Gaio Paradossi. "Design of Novel Polymer Shelled Ultrasound Contrast Agents: Towards an Ultrasound Triggered Drug Delivery." In Ultrasound Contrast Agents, 25–39. Milano: Springer Milan, 2010. http://dx.doi.org/10.1007/978-88-470-1494-7_3.
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Kwan, James J., and Constantin C. Coussios. "Triggered Drug Release and Enhanced Drug Transport from Ultrasound-Responsive Nanoparticles." In Design and Applications of Nanoparticles in Biomedical Imaging, 277–97. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-42169-8_13.
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Vannetti, Federica, Tiziana Atzori, Laura Fabbri, Guido Pasquini, Leonardo Forzoni, and Claudio Macchi. "Superficial Electromyography, Motion Analysis and Triggered-Stereo Cameras Technologies Applied to Ultrasound System User Interface Evaluation." In Advances in Intelligent Systems and Computing, 80–89. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-60483-1_9.
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"3 Trigger Finger." In Ultrasound of the Hand and Upper Extremity, edited by John R. Fowler and Nandkumar M. Rawool. Stuttgart: Georg Thieme Verlag, 2018. http://dx.doi.org/10.1055/b-0038-149594.
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Wilson-Morkeh, Harold, and Charles Mackworth-Young. "Non-Surgical Regional Therapy for Osteoarthritis: An Update and Review of the Literature." In Bone Tumors - Recent Advances and Modern Management [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.91458.
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Osteoarthritis (OA) is the most common joint condition worldwide. It can lead to chronic debilitating symptoms that can be definitively managed with surgical techniques at times. More frequently however, either due to age, extent of disease or patient choice, non-surgical approaches are preferred. They include topical therapies such as thermotherapy, ultrasound, laser treatment, non-steroidal anti-inflammatory drugs (NSAIDs) and capsaicin cream. Injections are another technique often implemented. These consist of intra-articular (IA) corticosteroid or hyaluronan injections, trigger point injections and subcutaneous sodium salicylate. Acupuncture and various types of external support are also widely used. This chapter examines the latest evidence and summarises the role of the various regional treatments available for use in the management of OA.
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Möhlenkamp, Stefan. "Coronary angiography." In The ESC Textbook of Sports Cardiology, edited by Antonio Pelliccia, Hein Heidbuchel, Domenico Corrado, Mats Börjesson, and Sanjay Sharma, 162–65. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780198779742.003.0019.
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Invasive coronary angiography is used in symptomatic athletes with clinical suspicion of coronary artery disease which presumably requires interventional therapy, i.e. mainly in acute coronary syndrome and myocardial infarction. Because of its invasive nature, it is not used in asymptomatic athletes. Advanced intra-coronary artery imaging, including intra-vascular ultrasound (IVUS), intra-coronary Doppler ultrasound (ICDUS) and assessment of fractional flow reserve (FFR), can help to improve understanding of epicardial and intra-myocardial microvascular causes of symptoms. Plaque rupture, plaque erosion, coronary vasospasm, and thrombotic coronary occlusion have been demonstrated subsequent to athletic activities, but it is uncertain to what extent exhaustive exercise triggered the symptoms that led to invasive angiography. Because of radiation exposure, use of contrast agent, and the costs of the test careful risk–benefit assessment is necessary, especially in asymptomatic athletes with risk factors and in young athletes.
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Kost, Joseph. "Ultrasound-Triggered Delivery of Peptides and Proteins from Microspheres." In Microparticulate Systems for the Delivery of Proteins and Vaccines, 463–76. CRC Press, 2020. http://dx.doi.org/10.1201/9781003067542-16.
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Kalla, Manish, and Julian Halcox. "Vascular imaging." In Hyperlipidaemia, 121–33. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199543502.003.0011.
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• Atherosclerosis is a dynamic process that affects most medium and large calibre arteries, particularly the coronary and carotid arteries. • Atherosclerotic changes in the arteries develop over many decades before clinical presentation. • First cardiac events are often either myocardial infarction or death, with most acute coronary events triggered by destabilization and rupture of lipid, rich, thin capped, usually only mildly obstructive plaques. • Early identification of subclinical atherosclerosis and high-risk plaque/preclinical disease is of value in assessing a patient's future risk of developing clinical disease. • Angiography remains the gold standard investigation but visualizes only stenoses, which are a late manifestation of the atherosclerotic process. • Newer modalities such as computed tomography (CT) angiography, B mode carotid ultrasound, and magnetic resonance imaging (MRI) can identify at-risk individuals without invasive investigations. • Functional and anatomical imaging together holds great promise in for accurate identification of patients with high-risk plaque.
Conference papers on the topic "Ultrasound trigger"
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Sikdar, Siddhartha, Jay P. Shah, Elizabeth Gilliams, Tadesse Gebreab, and Lynn H. Gerber. "Assessment of myofascial trigger points (MTrPs): A new application of ultrasound imaging and vibration sonoelastography." In 2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2008. http://dx.doi.org/10.1109/iembs.2008.4650480.
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Fusco, P., M. Celniku, W. Ciaschi, F. Angelucci, and F. Marinangeli. "74 Can the ultrasound-guided dry-needling associated with elastosonographic evaluation improve the treatment of the myofascial trigger points?" In ESRA 2021 Virtual Congress, 8–9–10 September 2021. BMJ Publishing Group Ltd, 2021. http://dx.doi.org/10.1136/rapm-2021-esra.74.
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Bhargava, Aarushi, Kaiyuan Peng, Jerry Stieg, Reza Mirzaeifar, and Shima Shahab. "Ultrasound Actuation of Shape-Memory Polymer Filaments: Acoustic-Thermoelastic Modeling and Testing." In ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/smasis2017-3832.
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Controlled drug delivery (CDD) technology has received extensive attention in the past three decades due to numerous advantages of this technology when compared to the conventional methods. Despite recent efforts and substantial achievements, controlled drug releasing systems still face major challenges in practice, including chemical issues with synthesizing biocompatible drug containers and releasing the pharmaceutical compounds at the targeted location with a controlled time rate. In this work, we present experimentally-validated acoustic-thermoelastic mathematical modeling to show the feasibility of using shape memory polymers (SMPs) and focused ultrasound (FU) technology for designing a novel drug-delivery system. SMPs represent a new class of materials that have the ability of storing a temporary shape and returning to their permanent or original shape when subjected to external stimuli such as heat. FU is used as a trigger for noninvasively stimulating SMP-based drug capsules. FU has a superior capability to localize the heating effect, thus initiating the shape recovery process only in selected parts of the polymer. A multiphysics model is developed, which optimizes the design of a SMP-based CDD system using acoustic-thermoelastic analysis of a filament as the constituting base structure and quantifies its activation through FU. The analytical and numerical models are divided into three parts. The first part studies the acoustic behavior of SMPs using Khokhlov-Zabolotskaya-Kuznetsov (KZK) model. The equation solves for acoustic pressure field in a hybrid time-frequency domain using operator-splitting method and examines the effects of absorption, diffraction and nonlinear distortion on the propagating wave in the medium. The second part provides a numerical model based on Penne’s Bioheat equation to estimate the thermal field developed in SMPs as a result of focused acoustic pressure field. The third part provides a numerical framework to predict the mechanical stresses developed in SMPs under FU and consequent shape recovery. The mechanical model is formulated by a compressible neo-Hookean constitutive equation, which assumes the SMPs behave as a thermoelastic material and predicts the shape memory effect under FU. Experimental validation is performed using a FU transducer in a water tank. The recovery of thermally responsive SMPs under FU predicted by our model shows a good accordance with the experiments. The modeling results are used to optimize parameters such as nonlinear properties, input frequency, source power and dimensional effects to achieve maximum shape recovery.
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Maier, Florian, Alexander Brunner, Jürgen W. Jenne, Axel J. Krafft, Wolfhard Semmler, and Michael Bock. "Robotically assisted velocity-sensitive triggered focused ultrasound surgery." In 12TH INTERNATIONAL SYMPOSIUM ON THERAPEUTIC ULTRASOUND. AIP, 2012. http://dx.doi.org/10.1063/1.4769934.
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Duryea, Alexander P., William W. Roberts, Charles A. Cain, and Timothy L. Hall. "Optically triggered solid state driver for shock wave therapy." In 11TH INTERNATIONAL SYMPOSIUM ON THERAPEUTIC ULTRASOUND. AIP, 2012. http://dx.doi.org/10.1063/1.4757314.
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Ferreri, Suzanne, and Yi-Xian Qin. "Alteration of Bone’s Nonlinear Elastic and Viscoelastic Nanomechanical Properties Is Triggered by Low Intensity Pulsed Ultrasound." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206711.
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Dynamic mechanotransduction, particularly under high frequency, low amplitude signals, has been proven effective in mediating bone loss and improving mechanical strength for tissues affected by estrogen deficient osteopenia. Ultrasound, which behaves as an alternating pressure wave in bone, may offer an effective, non-invasive technology for delivery of anabolic signals. In vitro, dynamic mechanical signals delivered using ultrasound have been shown to increase osteoblast proliferation [1], and in vivo studies have established ultrasound as an effective treatment for delayed and non-union fractures [2]. Previously, we showed that ultrasound signals similar to those currently used in a clinical setting for fracture healing were effective in mediating decreases in bone volume and mechanical strength at the millimeter length-scale in response to estrogen deficient osteopenia [3]. Due to bone’s inherent viscoelasticity and the dynamic nature of the applied ultrasound signals, it is particularly important to consider both elastic and viscous components of bone’s adaptive response to applied loads. In light of these findings, the goal of this study was to determine the role of therapeutic ultrasound signal intensity in modulating changes in bone’s nanoscale elastic and viscoelastic material properties associated with estrogen deficient osteopenia. We hypothesize that bone is sensitive to dynamic mechanical signals delivered via ultrasound and that bone’s tissue level nano-scale material properties, particularly nonlinear viscoelastic properties, are sensitive to ultrasound signal intensity.
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Takimoto, Kengo, Tatsuya Moriyama, Ryo Takagi, Shin Yoshizawa, Shin-ichiro Umemura, Yoichiro Matsumoto, Lawrence A. Crum, and Gail Reinette ter Haar. "Gel phantom containing controlled air to test Triggered HIFU exposure sequence." In 10TH INTERNATIONAL SYMPOSIUM ON THERAPEUTIC ULTRASOUND (ISTU 2010). AIP, 2011. http://dx.doi.org/10.1063/1.3607891.
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Escoffre, Jean-Michel, Bart Geers, Ine Lentacker, and Ayache Bouaka. "Evaluation of doxorubicin-containing microbubbles for ultrasound-triggered delivery." In 2011 IEEE International Ultrasonics Symposium (IUS). IEEE, 2011. http://dx.doi.org/10.1109/ultsym.2011.0447.
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Wilson, Katheryne E., Kimberly A. Homan, and Stanislav Y. Emelianov. "Remotely triggered contrast nanoagent for ultrasound and photoacoustic imaging." In 2010 IEEE Ultrasonics Symposium (IUS). IEEE, 2010. http://dx.doi.org/10.1109/ultsym.2010.5935757.
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Forsberg, Flemming, Dylan Curry, Priscilla Machado, Neil Zhao, Maria Stanczak, John R. Eisenbrey, Thomas P. Schaer, and Noreen J. Hickok. "Ultrasound Triggered Microbubble Destruction for Disrupting Biofilms in Synovial Fluid." In 2020 IEEE International Ultrasonics Symposium (IUS). IEEE, 2020. http://dx.doi.org/10.1109/ius46767.2020.9251545.
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