Medical devices; general and plastic surgery devices; classification of the focused ultrasound stimulator system for aesthetic use. Final rule.

The Food and Drug Administration (FDA) is classifying the focused ultrasound stimulator system for aesthetic use into class II (special controls). The special control(s) that will apply to the device is the guidance document entitled "Class II Special Controls Guidance Document: Focused Ultrasound Stimulator System for Aesthetic Use." The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

The effect of ultrasound on angiogenesis: an in vivo study using the chick chorioallantoic membrane.

PURPOSE: Ultrasound therapy induces clinical healing of irradiated avascular mandibular bone and fractures. In vitro ultrasound in tissue culture has been shown to stimulate bone formation synthesis and bone remodeling factors and to stimulate osteoblast proliferation. Therefore, the aim of the present study was to investigate the effect of short-wave (1-MHz) and long-wave (45-kHz) ultrasound on the vascularity of the chorioallantoic membrane (CAM) of a fertilized egg. MATERIALS AND METHODS: The nature of the angiogenic effect was investigated using the CAM of a fertilized egg by: (1) application of sonicated fibroblast media incorporated into methylcellulose disks onto the CAM and (2) direct application of the ultrasound, using both long-wave (45-kHz) and short-wave (1-MHz) frequencies at a range of intensities, to the surface of the egg. Angiogenesis was assessed quantitatively by three independent observers. RESULTS: Both ultrasound methods showed evidence of an angiogenic effect compared to controls. The most effective results were seen with direct application of a 45-kHz wave at an intensity of 15 mW/cm(2) and indirect application of the media of fibroblasts ultrasonicated at 1 MHz with an intensity of 0.4 W/cm(2). CONCLUSION: This model confirms that ultrasound can induce neoangiogenesis in vivo.

Medical devices; general and plastic surgery devices; classification of the low energy ultrasound wound cleaner. Final rule.

The Food and Drug Administration (FDA) is classifying the low energy ultrasound wound cleaner into class II (special controls). The special control that will apply to the device is the guidance document entitled "Class II Special Controls Guidance Document: Low Energy Ultrasound Wound Cleaner." The agency is taking this action in response to a petition submitted under the Federal Food, Drug, and Cosmetic Act (the act) as amended by the Medical Device Amendments of 1976, the Safe Medical Devices Act of 1990, and the Food and Drug Administration Modernization Act of 1997 (FDAMA). The agency is classifying this device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device. Elsewhere in this issue of the Federal Register, FDA is announcing the availability of the guidance document that will serve as the special control for the class II device.

Therapeutic ultrasound.

Therapeutic ultrasound has been in use for many years. Early applications were those for which tissue heating was the goal, and so it was used for soft tissue injuries such as may be incurred during sport. More recently, attention has been drawn both to high intensity focused beams that may be used for thermal ablation of selected regions, and also to low intensity fields that appear to be able to stimulate physiological processes, such as tissue repair, without biologically significant temperature rises. Ultrasonic tools are used for therapeutic effect in dentistry and are being investigated for use in thrombolysis. This paper reviews the various therapeutic applications of ultrasound.