Therapeutic Use Of Ultrasound Research Articles

AIUM Official Statement: Safe Use of Therapeutic Ultrasound.

AIUM Official Statement: Safe Use of Therapeutic Ultrasound.

Quantification of microbubble‐induced sonothrombolysis in an ex vivo non‐human primate model

BackgroundIn vitro studies with ultrasound (US) and microbubbles (MB) have reported that sono‐thrombolysis can be achieved at high peak rarefactional acoustic pressure amplitudes (PRAPAs) using 0.25 and 1.05 MHz US frequencies. ObjectiveThe aim of the current study was to determine if these parameters work on an ex vivo physiological model of thrombosis. MethodsA thrombogenic device was placed in an ex vivo chronic arteriovenous shunt in juvenile baboons. Platelet accumulation was measured by dynamic imaging of the device and the 10 cm thrombus tail with 111In‐labeled platelets. After 15 minutes of thrombus formation, treatment with either low‐dose recombinant tissue plasminogen activator (rtPA) or low‐dose rtPA + MB+US was performed for 20 minutes. Four US settings at 0.25% duty cycle were used: 0.25 MHz at PRAPAs of 1.20 and 2.20 MPa, and 1.05 MHz at 1.75 and 4.75 MPa. ResultsPlatelet accumulation was not inhibited by low‐dose rtPA or MB with US alone. Platelet accumulation was significantly reduced with 0.25 MHz US at 2.20 PRAPA (P < .001) and with 1.05 MHz at 1.75 MPa and 4.75 MPa (P < .05) when used with MB and low‐dose rtPA. Although this approach prevented platelet accumulation it did not cause thrombolysis on the device. ConclusionsrtPA + MB + US (0.25 and 1.05 MHz) resulted in inhibition of platelet accumulation on the thrombogenic device when moderately high PRAPAs (≥1.75 MPa) were used. These results taken in context with lytic effects of US on myocardial microthrombi and direct effect on myocardial blood flow and function provide direction for the use of therapeutic US in acute coronary syndromes.

Choosing Wisely Initiative: Analysis Of Twelve Years Of Therapeutic Ultrasound

In 2014, the Choosing Wisely Initiative partnered with the American Physical Therapy Association to produce a list of low-value physical therapy (PT) practices, titled “Five Things Physical Therapists and Patients Should Question.” This publication described the limited value of deep heat, or therapeutic ultrasound (TUS), to improve long term outcomes for a myriad of musculoskeletal conditions, yet TUS continues to be used. It is unclear how often TUS is used in contemporary PT practice, how its use has changed after this initiative and for what specific conditions it is most used. PURPOSE: To assess the historical use of TUS by physical therapists before and after the Choosing Wisely Initiative across a regional health network. METHODS: A de-identified Clinical Research Data Warehouse was queried using i2B2 software to collect the history of TUS usage by PTs between 2008 and 2019. The specific CPT code 97035 was used to identify TUS episodes of care. In addition, the total number of unique patients in PT each year was collected. Indications for individual TUS treatment units were analyzed in 2018 and 2019 to yield the most frequent ICD-10 codes for which TUS was performed. RESULTS: Episodes of TUS were standardized by the total number of patients seen in PT each year to account for the growth of the health network. The percentage of patients who received TUS each year was reported. TUS usage rates between 2008 and 2019 were compared using Pearson's two proportion Z-test. Utilization was significantly lower in 2019 (5.2%) than it was in 2008 (24.0%) (χ 2 = 2059.6, p-value < 2.2e-16). Between 2018 and 2019, 5,936 units of TUS were performed by 118 unique PT providers. TUS was commonly performed for shoulder pain (13.0%), ankle or foot pain (9.6%), neck pain (9.6%), knee pain (7.7%), hip pain (6.1%), low back pain (6.0%), unspecified chronic pain (4.3%), and Achilles tendinopathy (4.1%). CONCLUSION: Over the last 12 years, there has been a significant decrease in use of TUS by PTs. This decline coincides with the Choosing Wisely Initiative. However, TUS continues to be used, albeit at a significantly lower frequency, for treating musculoskeletal conditions despite having little evidence in improving long term clinical outcomes. Supported by NIH Grant UL1TR001436.

Induction of Skeletal Muscle Differentiation In Vitro by Therapeutic Ultrasound

Therapeutic ultrasound (TU) has been used for the last 50 y in rehabilitation, including treatment of soft tissues. Ultrasound waves can be employed in two different modes of operation, continuous and pulsed, which produce both thermal and non-thermal effects. Despite the large-scale use of TU, there are few scientific studies on its biologic effects during skeletal muscle differentiation. To better analyze the cellular effects of TU, we decided to follow cells in vitro. The main purpose of this study was to evaluate the effects of TU in primary chick myogenic cell cultures using phase contrast optical microscopy and immunofluorescence microscopy, followed by image analysis and quantification. Our results indicate that TU can stimulate the differentiation of skeletal muscle cells in vitro, as measured by the thickness of multinucleated myotubes, the ratio of mononucleated cells to multinucleated cells and expression of the muscle-specific protein desmin. This study is a first step toward a metrologic and science-based protocol for cell treatment under different ultrasound field exposures.

Overview of ultrasound usage trends in orthopedic and sports physiotherapy

BackgroundThe purpose of this study is to examine current beliefs about the use, the clinical importance, the theoretical fundamentals and the utilization criteria of therapeutic ultrasound (TUS) among physical therapists on the clinical practice in orthopedic and sports physiotherapy in Brazil.MethodsA brief survey was developed based on previous studies and was sent to 55 physical therapists with advanced competency in orthopedics and sports physiotherapy. The questions addressed general topics about the professional profile and ultrasound usage and dosage.ResultsOur data show the wide availability and frequent use of TUS in this sample of physical therapists. TUS is used in distinct musculoskeletal injuries and/or disorders in both acute and chronic conditions. Muscles, tendons and ligaments represented the major structures where TUS is used. Questions on the basic theory of TUS demonstrated a lack of knowledge of the ultrasound physiological effects as well as its interaction with biological tissues and TUS absolute contraindication.ConclusionA Brazilian profile about the US usage and dosage in orthopedic and sports physiotherapy is presented and highlights the need for a continuous upgrading process and further research into its effects.

Assay of therapeutic ultrasound induced‐antinociception in experimental trigeminal neuropathic pain

Trigeminal neuralgia is considered one of the most painful conditions, and pharmacological treatment can be as debilitating as the pathology itself. The aim of this work was to evaluate the effectiveness of pulsed therapeutic ultrasound (TU) on an experimental rat model of trigeminal neuropathic nociception (chronic constriction injury-infraorbital nerve; CCI-ION). To evaluate facial thermonociception, an apparatus that measured the reaction time for head withdrawal was constructed. After surgery, a gradual reduction in reaction time was observed until day 15 post-CCI, when the values became constant. Three ipsilateral applications of TU to post-CCI rats promoted an increase in latency time. This antinociceptive effect was evident even after the first TU application, reaching maximal values at 24 hr. The magnitude of this effect was proportional to ultrasonic wave intensity (0.3 and 0.4 W/cm(2)). Posttreatment with naltrexone (5 mg/kg, s.c.) completely blocked the hypoalgesic effect of TU. Pretreatment with an opioid antagonist was unable to block the antinociceptive effect during the first 8 hr, suggesting that opioids are involved only in the latter phase of the TU effects. Myeloperoxidase (MPO) levels in the infraorbital nerve were not increased by TU use, indicating that TU causes no injury or is at least insufficient to induce neutrophil migration. In conclusion, TU is an effective resource in a model of trigeminal neuropathic pain, with a mechanism involving opioid receptor activation, confirming its potential usefulness in the treatment of trigeminal neuralgia.

A randomized, double-blind clinical trial comparing the effects of continuous and pulsed ultrasound in patients with chronic rhinosinusitis

The objective of the present study was to compare the effects of continuous ultrasound (CUS) with pulsed ultrasound (PUS) in patients with chronic rhinosinusitis (CRS). In this prospective, randomized, double-blind, parallel group study, 40 patients (10 losses) with CRS participated. Patients received either continuous or pulsed (1:9) 1 MHz ultrasound (US) using a US head of 1 cm2 at 1 W/cm2 and 0.5 W/cm2 for the maxillary and frontal sinuses, respectively. Treatment was performed in 10 sessions, 3 days per week, with US given every other day. The primary outcome measure was percent improvement in the Sinusitis Symptom Score. Measurements were taken before and after 10 treatment sessions. The patients were followed up monthly for 2 months. After treatment, both groups improved significantly on the Sinusitis Symptoms Score. Patients who received PUS had significantly decreased total symptom scores compared with patients receiving CUS (mean change 9.8 vs. 5.6, p = 0.049). The percent improvement in the Sinusitis Symptom Score between the PUS group (65.2 SD 23.1) and the CUS group (43.9 SD 40.7) was not statistically significant (p = 0.09). The effect size for each treatment was large; PUS: d = 3.92 and CUS: d = 1.93. Symptom improvement in both groups was similar at the 2-month follow-up. These results support the use of therapeutic US for CRS. This pilot study gives only marginal evidence to favor PUS over CUS.

Análise histológica em tecido epitelial sadio de ratos Wistar (in vivo) irradiados com diferentes intensidades do ultrassom

Ultrasound (US) is a widely used and studied resource for physical therapy treatments. Given the scarcity of studies on the effects of US on healthy tissue, many physical therapy professionals make unfounded decisions regarding its methods and parameters of application. The possible histological and morphometric changes in the healthy tissue of Wistar rats in vivo irradiated with different intensities of US were evaluated. Thirty Wistar rats, randomly distributed among five groups of six animals each, were treated on the right side of the dorsal region, over an area of 4 cm(2). The left side served as a control. The treatment was applied over a four-day period, with two mins. of daily irradiation. The output intensity was checked using a precision dosimeter before the applications. Histological and morphometric analyses were performed using the Image Tool software. There were slight inflammatory infiltration and thinning of the dermis fibers, particularly in the groups irradiated with 1.5 and 2 W/cm(2). There was also thickening of the epidermis in the samples from the irradiated animals. To evaluate the quantitative results, the statistical analyses consisted of one-way ANOVAs with the post-hoc Tukey tests. There were significant differences in epidermis thicknesses between the control group and the groups irradiated with 1.0, 1.5 and 2.0 W/cm(2). Higher doses of US produced changes in the epidermis and dermis, i.e. increased thickness and collagen fiber thinning and proliferation, respectively. These results serve as a warning of the possible implications of therapeutic ultrasound use in esthetics.

Análise longitudinal de músculos sóleos, de ratos, submetidos a alongamento passivo com uso prévio de ultrassom terapêutico

O alongamento muscular é muito difundido entre atletas e pessoas envolvidas em atividades físicas, além de procedimento rotineiro em clínicas de fisioterapia, principalmente visando o aumento na flexibilidade. O ultrassom terapêutico possui ações térmicas e atérmicas, o que gera possibilidades de aumento de extensibilidade tecidual e metabolismo celular, e pode auxiliar nos efeitos anabólicos do alongamento estático. O objetivo deste estudo foi analisar os efeitos do alongamento passivo estático em músculo sóleo esquerdo (MSE) de ratos, associado ao uso do ultrassom terapêutico, sobre alterações longitudinais do tecido muscular. Foram utilizados 42 ratos Wistar, divididos em grupos tratados com ultrassom terapêutico com doses térmicas e não, e subsequente alongamento estático em três séries de 30s, além de grupos apenas tratados com ultrassom ou alongados, durante 15 dias de tratamento. Foram comparadas as variações encontradas entre o MSE e o MSD de cada grupo. As variáveis foram: comprimento muscular, estimativa de sarcômeros em série na fibra e ao longo do músculo, e comprimento de sarcômeros. Os resultados das variáveis analisadas apontaram alterações no comprimento muscular de repouso nos grupos em que foi associado ultrassom terapêutico, em dose térmica, ao alongamento estático, mas para as outras variáveis analisadas não houve diferenças significativas. Conclui-se que o alongamento passivo estático e o uso associado do ultrassom terapêutico, de forma térmica, produziram apenas aumento no comprimento muscular em repouso.

Ultra-som terapêutico e imobilização na reparação do trauma muscular

INTRODUÇÃO: Avaliamos os efeitos do ultra-som terapêutico (UST), adicionado ou não à imobilização gessada (IG), como forma de tratamento à lesão muscular por impacto analisando as propriedades mecânicas de alongamento e carga nos limites de proporcionalidade e máximo, rigidez (R) e resiliência do músculo gastrocnêmio. METODOLOGIA: Utilizamos 70 ratas divididas em 7 grupos:Grupo 1-Controle;Grupo 2-Sem tratamento,Grupo 3-IG por 24 horas;Grupo 4-IG por 72 horas; Grupo 5-UST sem presença de IG;Grupo 6-IG por 24 horas associada ao UST;Grupo 7-IG por 72 horas associada ao UST. RESULTADOS: As propriedades de carga no limite de proporcionalidade e carga máxima mostraram que o grupo estimulado com o UST comportou-se de modo semelhante ao grupo controle. A propriedade de alongamento no limite de proporcionalidade não diferenciou os grupos; o alongamento máximo do grupo estimulado com (UST) e dos grupos imobilizados por 72 horas foram comparáveis ao grupo controle. CONCLUSÃO: O grupo estimulado (UST) apresentou rigidez similar ao grupo controle e resiliência superior a todos os grupos. A utilização isolada do UST forneceu resultados similares àqueles considerados como normais, o mesmo não sendo observado quando o UST foi associado à IG.

O ultra-som terapêutico de 1 MHz, na dose de 0,5 W cm-2, sobre o tecido ósseo de cães avaliado por densitometria óptica em imagens radiográficas

As lesões tendíneas nas extremidades distais dos membros estão entre as mais freqüentes alterações do aparelho locomotor na rotina clínico-cirúrgica humana e animal e, não raro, necessitam de terapias adjuvantes para seu completo retorno às funções fisiológicas. O ultra-som terapêutico (UST) é a modalidade mais utilizada nas clínicas de reabilitação para tratar lesões tendíneas, mas devido à falta ou a divergências de estudos específicos sobre seus efeitos no tecido ósseo, sua utilização sobre as regiões distais dos membros, ricas em protuberâncias ósseas e áreas desprovidas de cobertura muscular, sempre preocuparam os profissionais da área médica. No intuito de esclarecer os efeitos do UST sobre o tecido ósseo, seis cães receberam tratamento ultra-sônico contínuo, de 1MHz, durante cinco minutos diários, por um período de 20 dias sobre a região craniodistal do rádio e da ulna. A intensidade do UST aplicada foi de 0,5W cm-2 no membro torácico direito, ficando o membro contralateral como controle. A região distal de ambos os membros torácicos foi radiografada para análise de densitometria óssea em imagens radiográficas, antes do início da terapia e ao final do tratamento. Não houve alterações significativas de densidade mineral óssea entre os membros tratados e os controles. Conclui-se que dentro dos parâmetros utilizados no experimento a utilização do UST em regiões ósseas protuberantes ou desprovidas de cobertura muscular pode ser feita com segurança.

Author response to invited commentary on “A Survey of Therapeutic Ultrasound Use by Physical Therapists Who Are Orthopaedic Certified Specialists.” Wong RA, Schumann B, Townsend R, Phelps CA. Phys Ther. 2007;87:999–1001.

Author response to invited commentary on “A Survey of Therapeutic Ultrasound Use by Physical Therapists Who Are Orthopaedic Certified Specialists.” Wong RA, Schumann B, Townsend R, Phelps CA. Phys Ther. 2007;87:999–1001.

A Survey of Therapeutic Ultrasound Use by Physical Therapists Who Are Orthopaedic Certified Specialists

For many years, ultrasound (US) has been a widely used and well-accepted physical therapy modality for the management of musculoskeletal conditions. However, there is a lack of scientific evidence on its effectiveness. This study examined the opinions of physical therapists with advanced competency in orthopedics about the use and perceived clinical importance of US in managing commonly encountered orthopedic impairments. Four hundred fifty-seven physical therapists who were orthopaedic certified specialists from the Northeast/Mid-Atlantic regions of the United States were invited to participate. A 77-item survey instrument was developed. After face and content validity were established, the survey instrument was mailed to all subjects. Two hundred seven usable survey questionnaires were returned (response rate=45.3%). According to the surveys, the respondents indicated that they were likely to use US to decrease soft tissue inflammation (eg, tendinitis, bursitis) (83.6% of the respondents), increase tissue extensibility (70.9%), enhance scar tissue remodeling (68.8%), increase soft tissue healing (52.5%), decrease pain (49.3%), and decrease soft tissue swelling (eg, edema, joint effusion) (35.1%). The respondents used US to deliver medication (phonophoresis) for soft tissue inflammation (54.1%), pain management (22.2%), and soft tissue swelling (19.8%). The study provides summary data of the most frequently chosen machine parameters for duty cycle, intensity, and frequency. Ultrasound continues to be a popular adjunctive modality in orthopedic physical therapy. These findings may help researchers prioritize needs for future research on the clinical effectiveness of US.

Treatment of Deeply Located Acute Intravascular Thrombi With Therapeutic Ultrasound Guided by Diagnostic Ultrasound and Intravenous Microbubbles

We sought to determine the added value of simultaneous imaging of intravenously infused microbubbles that are being used to dissolve an intravascular thrombus with therapeutic ultrasound (TUS). In a chronic canine arteriovenous graft occluded by a thrombus, TUS (1 MHz) was applied through a 6-cm-thick tissue-mimicking phantom (measured mean +/- SD peak negative pressure through the phantom, 958 +/- 104 kPa) during an intravenous infusion of either saline (n = 6 occlusions) or lipid-encapsulated microbubbles (ImaRx Therapeutics, Inc, Tucson, AZ). Therapeutic ultrasound was intermittently applied during the microbubble infusion either at set time intervals (n = 6 occlusions) or when simultaneous diagnostic ultrasound (DUS) indicated a sustained presence of microbubbles (n = 12 occlusions). Success was defined as return of rapid flow within the graft (grade 3 flow). Diagnostic ultrasound showed microbubbles moving through small channels within the thrombus before angiographic evidence of flow in the graft. This guided the timing of TUS application better than using set time intervals. Angiographic clearance of the thrombus and restoration of grade 3 flow at 45 minutes of treatment were seen in 33% of deeply located thrombosed grafts treated with TUS at set time intervals and 92% of grafts treated with TUS guided by DUS (P < .001 compared with set time intervals). The use of TUS with intravenous microbubbles has a high success rate in recanalizing deeply located thrombosed arteriovenous grafts when performed with DUS guidance.

The use of therapeutic ultrasound by physical therapists in Dutch primary health care.

The purposes of this study were to describe the use of ultrasound by Dutch physical therapists and to address the question of whether this use is what would be considered correct. Physical therapists in the Dutch primary health care system gathered data on 17,201 patients, addressing reasons for referral, treatment goals (in terms of impairments and disabilities), and physical therapy interventions. Patients treated with ultrasound (n = 3,959) were compared with a reference group of patients who were not treated with ultrasound (n = 13,242). Physical therapists applied ultrasound for soft tissue injuries of recent onset, mainly aiming to reduce pain and swelling. Ultrasound was used in all phases of treatment and was not restricted to the first 3 weeks of treatment. Ultrasound was combined relatively infrequently with exercise and relatively frequently with massage. Regarding the indications for referral and treatment goals chosen, the actual use of ultrasound corresponds to assumptions about expected use. The timing of its application and the combination with other forms of therapy do not correspond in all aspects to the assumptions made.