VOLUME 102 . NUMBER 3 • JULY 1998
AMERICAN SOCIETY OF
PLASTIC AND RECONSTRUCTIVE
Journal of the American Society of Plastic and
Reconstructive Surgeons, Inc.
Official Organ of the American Association of Plastic Surgeons
Official Organ of the American Society for Aesthetic Plastic Surgery, Inc.
Official Organ of the American Society of Maxillofacial Surgeons
INSTRUMENTATION, CLINICAL EXPERIENCE,
116 Pinehurst Avenue
New York, NY 10033-1755
Ultrasonic lipectomy, a recent extension of ultrasonically assisted aspiration to adipose tissue, employs technology first introduced to surgery in 1967 by Kelman (1) for the removal of cataracts (2,3). Ultrasonic intracapsular cataract extraction itself directly evolved from ultrasonic dental scaling first introduced by Balamuth in 1958 (4).. The principle of phacoemulsilfication, as the ophthalmic technique is known, was later broadened in 1976 to include brain (5) and spinal cord (6) tumors as well as the prostate (7), bladder tumors, renal and hepatic tissue (8), coronary procedures(9) and ovarian tumors (10). The instrumentation and its operating characteristics have been comprehensively reviewed, and the physical principles responsible for its tissue-selective attributes strongly correlate with cavitation of intercellular water (12).
In typical equipment a hollow metal tube is made to vibrate in the frequency range between 20 and 60 kHz. Vacuum is applied to the bore while irrigation fluid is continuously conveyed over the tube to facilitate aspiration, remove incidentally generated heat, and enhance visibility. The vibration is sufficiently large to cause the separation of tissue when the end of the tube contacts target tissue. Dissection only occurs within 1 to 2 mm of the point of tip contact. Typically the power delivered to tissue ranges from one to as much as 30 watts, but the power density, given the size of the tips used, ranges from 500 to as much as 3000 W/cm2. The parted tissue is commonly aspirated through the bore into a suction receptacle or biopsy trap located outside of the sterile field.
Ultrasonic aspiration is distinguished from other intraoperative modalities such as electrosurgery and the laser in three important respects: (I) water-related tissue selectivity, (II) complete aspiration of all dissections, and (III) macroscopic athermal operation. When tissue is readily amenable to ultrasonic effect, the dissection margins evidence no burning or eschar (8).
The physical effects responsible for the unique surgical benefits of the technique are believed to he related to cavitation (18), a process that, like the laser and electrosurgical equipment, produces very high temperatures and even light (14) (sonoluminescence) and as well as very high but again extremely localized pressures (15). Unlike either the laser or electric scalpel, cavitation acts only on a microscopic level, and ultrasonic aspirators do not rely on tissue vaporization for dissection. The safety of ultrasonic aspiration in general surgery, neurosurgery and gynecological surgery has been studied over the last 20 years and the technique found to he an important adjunctive procedure (5, 6, 16, 17). Flow cytometric studies of cell DNA have confirmed that the aspirated tissue is both morphologically and functionally intact (18), and other researchers have used leukocyte sonicates as a source for both enzyme assay and DNA amplification (19, 20), a reliable indicator of structural preservation. To our knowledge there are no reported incidences of tumor or tissue transformation resulting from the procedures.
Ultrasonic-assisted lipectomy uses identical technology and functions in the same frequency regime of the long-used and extensively evaluated ultrasonic aspirators. Typically, the hollow surgical tip for this equipment measures approximately 2.3 mm in diameter, moves some 200 microns at a frequency of 27 kHz, and provides a surgically useful power output of between 10 and 40 watts. The actual power density delivered to tissue at the point of contact ranges from 1000 to 3000 W/cm2 (21) which is comparable to the currently available ultrasonic surgical aspirators manufactured and approved for open-site procedures (22). Investigators have reported histologic studies revealing intact aspirated adipose tissue and preservation of patent vasculattire (23-25). 1t therefore appears that experience with ultrasonic lipectomy will be accorded the same benefits obtained in other surgical specialties over the last 30 years, provided the cautions advised in its use are observed.
1. Kelman. C. Phaco-emulsification and aspiration. Am. J. Ophthalmol. 64: 23, 1967.
2. Kelman, C. Phaco-emulsification and aspiration: A report of 500 consecutive cases. Am. J. Ophthalmol. 75: 764, 1973.
3. Emery, J. M., and Little. J. H. Pharo-emulsification and Aspiration of Cataracts. St. Louis: Mosby, 1979.
4. Forrest, J. O. Ultrasonic scaling, a live year assessment. Br. Dent. 4. 122: 9, 1967.
5. Flamm, E. S., Ransohoff. J., Wuchinich, D., and Broadwin, A. Preliminary experience with ultrasonic aspiration in neurosurgery. Neurosurgery 2: 240, 1978.
6. Epstein, F., and Epstein, N. Surgical Management of Extensive Intramedullary Spinal Cord Astrocytomas in Children. Concepts in Pediatric Neurosurgery II, American Society for Pediatric Neurosurgery, Pp. 2944, 1982.
7. Malloy, T., and Wuchinich, D. Bladder outlet obstruction treated with transurethral ultrasonic aspiration. Urology 37: 512, 1991.
8. Addonizio, J., Choudhury, M., Sayegh, N., and Chopp, R. Cavitron Ultrasonic Surgical Aspirator: Applications in urology surgery. Urology 23: 417, 1984.
9. Mitsui, T., Onizuka, M., Ijima. H., et al. Ultrasonic aspiration in coronary artery surgery. Ann. Thorac. Surg. 40: 199, 1985.
10. Adelson, M. D., et al. Cvtoreduction of ovarian cancer with the Cavitron ultrasonic surgical aspirator. Obstet. Gynecol. 72: 140, 1988.
11. Cimino, W. W., and Bond, L. J. Physics of ultrasonic surgery using tissue fragmentation: Parts 1 and 2. Ultrasound Med. Biol. 22: 89, 1996.
12. Wuchinich, D. The Physical Evidence for Cavitation as the Agent of Ultrasonic Aspiration. Trans. Ultrasonic Industry Association, 26th Symposium, Columbus, Ohio, October 1995.
13. O'Leary, R., et al. The bactericidal effects of dental ultrasound on Actinobacillus actinomycetemcomitans and Porpbyromonas gingivalis: An in vitro investigation. J. Clin. Periodontol. 24: 432, 1997.
14. Roy, R. A., Ahmad, M., and Crum, L. A. Physical mechanisms governing the hydrodynamic response of an oscillating ultrasonic file. Int. Endod. J. 27: 197, 1994.
15. Suslick, K. (Ed.). Ultrasound: Its Chemical, Physical and Biological Effects, VCH Pub., 1988.
16. Young, W., Cohen, A., Hunt, C., and Ransohoff, J. Acute physiological effects of ultrasonic vibrations on nervous tissue. Neurosurgery 8: 689, 1981.
17. Gleeson, M. J., et al. A morphological study of the effect of the Cavitron ultrasonic surgical aspirator system near human peripheral nerves. Arch. Otolaryngol. Head Neck Surg. 113: 530, 1987.
18. Thompson, M. A., Adelson, M. D.. Jozefczyk, M. A.. et al. Structural and functional integrity of ovarian tumor tissue obtained by ultrasonic aspiration. Cancer 67: 1326, 1991.
19. Louie, E., Rafi, M. A., and Wenger, D. A. Leukocyte sonicates as a source for both enzyme assay and DNA amplification for mutational analysis of certain lysosomal disorders. Clin. Chim. Ada 199: 7, 1991.
20. Wyber, J. A., Andrews, J., and D'Emanuele, A. The use of sonication for the efficient delivery of plasmid DNA into cells. Pharm. Res. 14: 750. 1997.
21. Specification. Lipectron, Medicarnat, Malakoff. France. Probe tip diameter is given as 3-5 mm, frequency, 27 kHz, tip vibration excursion 70-200 microns.
22. CUSA System, Valleylab Inc., 5920 Longbow Drive, Boulder, CO.; Bovie Ultrasonic Aspirator, MDT Diagnostic Company, 7371 Spartan Boulevard East, North Charleston, S.C.; Ultra Ultrasonic Aspirator, Sharplan Lasers, Inc., One Pearl Court, Allendale, N.J.; Selector Ultrasonic Aspirator, Elekta Instruments Inc., 8 Executive Park West, Atlanta, Ga.
23. Adamo, C., Mazzochi, M., Rossi, A., et al. Ultrasonic liposculpturing: Extrapolations from the analysis of in vivo sonicated adipose tissue. Plast. Reconstr. Surg. 100: 220, 1997.
24. Zocchi, M. Ultrasonic liposculpturing. Aesthetic Plast. Surg. 16: 287, 1992.
25. Strauch, B., Giampapa, V., and DiBernardo, B. Ultrasonic liposuction utilizing simultaneous suction, irrigation and ultrasonic energy: A preliminary report, 1994 (available from author).