Ultrasound therapeutic

Nonpharmacologic therapies include reassurance and counseling, stress management, relaxation training, and biofeedback. Physical therapeutic options (e.g., heat or cold packs, ultrasound, electrical nerve stimulation, massage, acupuncture, trigger point injections, occipital nerve blocks) have performed inconsistently. 

Zhou XD, Ren XL, Zhang J, He GB, Zheng MJ, Tian X, Li L, Zhu T, Zhang M, Wang L, Luo W (2007) Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid utility of contrast-enhanced ultrasonography. European Journal of Radiology 62 289-294. 

One of the first applications of ultrasound in medicine was the so-called ultrasonic massage introduced in Germany before the Second World War. This was introduced as a substitute for the hands of the masseur in patients who had suffered from fractures and similar injuries. Rubbing movements are capable of improving the circulation very considerably and help also to break down adhesions between muscles and their sheaths that limit the range of movement. The use of ultrasound for the treatment of sporting injuries, particularly strains and tennis elbow is now commonplace as equipment for this purpose is readily commercially available to the physiotherapist. This is one of the first uses of ultrasound in the treatment of medical problems and is part of a new field of medicine called therapeutic ultrasound [15]. 

The interaction of ultrasound waves with microbubbles allows a drug (including genetic material for gene therapy [10]) to be released from the particles selectively at the desired insonified areas of the body, thus allowing targeted delivery of therapeutic agents. Currently, this approach is still far from clinical application. 

E. Therapeutic response In anovulatory women, the goal of therapy is adequate follicular development as determined by ultrasound in combination with measurement of serum estradiol levels. In men, the aim of treatment is maintenance of serum testosterone levels within the normal range. 

It is therefore desirable to devise strategies both to enhance the penetration of molecules, which can already breach the skin barricade passively to some extent, and also to widen the spectrum of drug molecules that can penetrate the skin at therapeutically beneficial doses. Many tactics have been utilized to help overcome the barrier function. These include chemical means (e.g., chemical penetration enhancers or entrapment of molecules within lipid vesicles) or physical methods (such as ultrasound, microneedles, or electrical methods). Two important electrical methods are iontophoresis and electroporation. 

High-frequency or diagnostic ultrasound in clinical imaging (3-10 MHz) Medium-frequency or therapeutic ultrasound in physical therapy (0.7-3.0 MHz) Low-frequency or power ultrasound for lithotripsy, cataract emulsification, liposuction, tissue ablation, cancer therapy, dental descaling, and ultrasonic scalpels (18-100 kHz)... 

Mitragotri, S. 2005. Healing sound The use of ultrasound in drug delivery and other therapeutic applications. Nat Rev Drug Discov 4 255. 

Johnson, M.E., et al. 1996. Synergistic effects of chemical enhancers and therapeutic ultrasound on transdermal drug delivery. J Pharm Sci 85 670. 

The recommended surveillance routine is for a CT scan at I, 6, and 12 months and annually thereafter. If an endoleak is detected, the frequency of the scans increases to every six months until resolution of the endoleak is detected. Investigators have compared duplex ultrasound with CT scan for surveillance and found that CT scan is superior for endoleak detection (32). Since endoleaks are an important complication with therapeutic implications, CT scans should be used rather than duplex examination for repair surveillance. 

Fig. 6.20 (a) Piezoceramic parts for a range of applications including accelerometers, underwater acoustics, pressure and liquid level sensors, medical diagnostics and therapeutics and NDT the ultrasound focusing bowls are for medical imaging and for producing high-intensity focused ultrasound. 

Treat, L.H., McDannold, N., Vykhodtseva, N., Zhang, Y., Tam, K., and Hynynen, K. (2007) Targeted delivery of doxorubicin to the rat brain at therapeutic levels using MRI-guided focused ultrasound. Int. J. Cancer 121,901-907. 

Ultrasound-assisted soft digestion has been used for other practical purposes from which analytical chemists can derive new applications. One case in point is in medicine, where ultrasound has been used as an adjunctive therapeutic treatment for clot dissolution of pharmacological thrombolysis. The combination of externally applied low-frequency high-intensity US with fibrinolytic therapy resulted in more rapid and complete reperfusion than the application of US or administration of fibrinolytic agents alone [42]. 

The systematic study of polar permeant permeation served to confirm the existence of a porous permeation pathway through the HEM. It also led to the characterization of important properties of this pathway. The results of this study demonstrated that the diffusion of polar permeants through skin is limited by the low effective porosity of the HEM and by hindrance effects due to restrictive pore dimensions. Effectively enhancing the transport of polar drugs in the MW range of many therapeutic peptides may require increasing the effective Rp of the HEM as well as the effective porosity/tortuosity ratio. Perhaps novel combinations of chemical permeation enhancers and physical means such as an applied electrical field or ultrasound may be necessary to achieve this objective. 

Kost, J. Ultrasound for controlled delivery of therapeutics. Clin. Mater. 1993, 13 (1 ), 155-161. 

Ultrasound at various frequencies in the range of 20 kHz to 16 MHz has been used for sonophoresis. These studies of sonophoresis can be classified into three categories based on the ultrasound frequency used, i.e., therapeutic, high-frequency, and low-frequency ultrasound. 

---