High-power low-frequency ultrasound: A review of tissue dissection and ablation in medicine and surgery

Abstract

Ab s t r a c t High-power low-frequency ultrasound in the range 20-60 kHz has wide ranging clinical applications in surgical and medical instruments for biological tissue cutting, ablation or fragmentation, and removal. Despite widespread clinical application and common device operating characteristics, there is an incomplete understanding of the mechanism of tissue failure, removal and damage. The relative contribution of cavitation, direct mechanical impact and thermal effects to each process for specific tissue types remains unclear. Different and distinct mechanisms and rates of tissue removal are observed for interaction with soft and hard tissue types. Device operating parameters known to affect the interaction include frequency, peak-peak tip amplitude, suction and application time. To date, there has been little analysis of the effect of variations in, and interactions of, these parameters on tissue removal and damage for individual biological tissue types. Potential controllable damage mechanisms occurring in tissues include alteration in global biomechanical properties, histomorphological changes, protein denaturation and tissue necrosis. This paper presents a critical review of the literature on the clinical application, mechanism of tissue interaction, removal and residual tissue damage. It describes known mechanisms for distinct tissue types.

Ultrasound applications to medicine part i: physical principles.

“…There is also Physiotherapy utilization [55] as the treatment of cervical pain [56] [57], its use in surgical and medical instruments (20 to 60 kHz) for dissection, ablation [58] [59], fragmentation and removal of biological tissue [60], activation of transplanted organs [61], biopsies [62] [63], vacuum biopsies [64], orthodontics [65], in obstetrics [66] and ambulatory gynecology [67] [68], pediatric anesthesia [69], forensic examinations [70] or simply to disinfect medical instruments [71].…”

Inspiration from Victorian times in Ultrasonic Surgical Tool Design

“…The first report of the use of ultrasound in dentistry was published in 1952 when an industrial ultrasonic grinder was used to prepare cavities in extracted human teeth [1], and further applications in medical practice started to emerge rapidly. In 1970, Balamuth patented use of ultrasonic frequency vibratory forces for removal of layers of highly compliant biological tissue [2] and in 1967, Kelman reported the use of a combination of low frequency ultrasound and aspiration for removal of human tissue [3].…”

“…Nevertheless any development of an ultrasonic cutting instrument must account for associated vibrational energy, and the use of such a device may be very different from the cutting process associated with rotary burrs. An ultrasonic surgical hand piece usually consists of four basic elements: a generator or power supply, an ultrasonic motor (transducer), a mechanical wave amplifier (referred to as an acoustic horn) and a sonotrode (or probe) [1]. The generator converts electrical signals at low-frequency into high-frequency current to drive the transducer for conversion into longitudinal or transverse low amplitude mechanical vibrations, at 20-60 kHz for the applications reviewed [1].…”

“…An ultrasonic surgical hand piece usually consists of four basic elements: a generator or power supply, an ultrasonic motor (transducer), a mechanical wave amplifier (referred to as an acoustic horn) and a sonotrode (or probe) [1]. The generator converts electrical signals at low-frequency into high-frequency current to drive the transducer for conversion into longitudinal or transverse low amplitude mechanical vibrations, at 20-60 kHz for the applications reviewed [1]. The vibration amplitude is usually of the order of a few microns and so this is transmitted to a horn which is used to increase or decrease the amplitude.…”

Characterization of Suction and CUSA Interaction with Brain Tissue

“…A general overview of the ultrasound technology in surgery is given in [9]. Briefly, the ultrasonic aspirator differs from the basic aspirator in its ability to generate a high frequency vibration, which liquefies soft tissues in the vicinity of its tip.…”