908
THE ULTRASONIC SCALPEL* W. JOHN B. HODGSON, M.S., F.R.C.S. Assistant Professor of Surgery The Mount Sinai School of Medicine of the City University of New York New York, New York Assistant Chief, Surgical Service Veterans Administration Medical Center Bronx, New York
DNURING the past two years the author has explored surgical techniques with the ultrasonic scalpel. Early dog studies ascertained in which tissues this instrument would be useful, and three operative techniques were devised: tissue aspiration, tissue incision and tissue dissection. Continuing laboratory and clinical work showed the potential value of the ultrasonic scalpel in reducing blood loss in oral, hepatic, and pancreatic surgery, partial splenectomy and pneumonectomy, flap dissection, dissection of solid tumors, fulguration of rectal cancers, and mucosal proctectomy. MATERIALS AND METHODS
The ultrasonic scalpel. The device is a logical development of the Cavitron-Kelman Phaco-Emulsifier"1' which is in general use for cataract surgery '2 and the preferred method in many centers.3 In February 1976 the Cavitron Ultrasonic Aspiration Device (CUSAT'N System), a larger and more powerful instrument than the Phaco-Emulsifier, was used, with favorable results, to aspirate neurogenic tumors.4 In the Surgical Research Laboratories of the Bronx Veterans Administration Medical Center and subsequently clinically, the CUSAT1i System was examined, evaluated, and successfully used as an ultrasonic scalpel in general surgery.5 The ultrasonic scalpel consists of a power and control console, and requires only standard operating room electrical connections to which a gas sterilizable handpiece is connected. In neurosurgery a pistol grip is used,4 but for general surgery the pencil grip is preferred.5 i; Briefly, the handpiece is constructed with a stainless steel water cooled jacket inside of which is a magneto strictive device attached by a connecting body to a *Presented before the Section on Surgery of the New York Academy of Medicine May 8, 1979. Address for reprint requests: 43-30 38th Street, Long Island City, N.Y. 11101.
Bull. N.Y. Acad. Med.
~
~
~
ULTRASONIC SCALPEL LRSNCS
909
cone-shaped titanium amplifier, only 2 mm. wide at its open tip. The titanium amplifier is housed in a plastic flue except for. the last 4 mm. of the tip. The action of the ultrasonic scalpel depends on resonant vibration of the magneto strictive transducers. These are simply long metal structures which vibrate longitudinally in response to an alternating electric current of exactly the frequency required to produce such vibration, which is passed through a coil around them. When the electric coil is activated, contraction and expansion of the magneto strictive transducers and of the cone shaped amplifier tip follows. Each contraction and expansion occurs about the resting position, with a maximum excursion of 150 microns, resulting in a total stroke of 300 microns. This ultrasonic vibration is quite unlike that of reciprocating cutting devices, nonuniform and remarkable for the very high velocities achieved at the extremes of movement. Hence tissue within a 1 mm. or 2 mm. radius from the tip is disrupted and aspirated. A technician sets up the instrument and controls the ultrasonic power available in the handpiece. When low power is used, minimal tissue fragmentation occurs. Tissue with a high water content is disrupted and other tissues, such as blood vessels, left intact. When high power is used, fragmentation is more rapid, and, despite the high collagen content of blood vessels, carelessness results in easily puncturing them. The technician also controls irrigation and aspiration rates. Low irrigation rates are used when heat is required at the tip for cautery. Because aspiration tubing cannot be cleaned, a new CUSA PAK"-' is required for each procedure. This fresh sterile tubing connects the handpiece to the console, and requires a technician or nurse to plug it into the console, after which the surgeon can commence the procedure. Animal work. Initial work with dogs5 demonstrated that the ultrasonic scalpel can perform a liver biopsy directly, without catgut hemostatic sutures, and in fact established that the liver parenchyma was removed but the vessels were not. These were easily tied and biopsies could be taken bloodlessly and quickly, findings more than adequately confirmed in baboons. It was also established that the dog spleen can be divided using the ultrasonic scalpel and bleeding prevented by tying vascular bundles exposed during the incision. In the abdomen, division of the stomach or bowel wall was slow and unsatisfactory, but it was relatively easy to strip antral mucosa or small bowel mucosa directly from submucosa and muscle. In addition, lung tissue could be divided and apparently sealed. On the Vol. 55, No. 10, November 1979
910
W. J. W. J. D. D. HODGSON HODGSON
other hand, partial nephrectomy did not prove to be a bloodless procedure. More extensive experimental operative procedures were then carried out using an ultrasonic scalpel.6 Hemihepatectomy could be performed with despatch, and pancreatic acinar tissue could be stripped from the pancreatic duct of a dog, which, although only 1 mm. wide, could be left intact. This was accomplished in a series of five dogs for 3 cm. to 4 cm., leaving normal pancreatic tissue proximal and distal to the stripped duct. Because mucosal stripping appeared to be a simple procedure by direct application of an ultrasonic scalpel to bowel mucosa, a study was set up, which continues, to test the feasibility of mucosal proctectomy and endorectal pull through in dogs. This has been performed with minimal blood loss on 17 dogs to date and all have been continent of stool postoperatively. Adequate adherence has been obtained between the serosa of the ileum and denuded rectal submucosa, although in earlier cases some retraction occurred. Later, using an ultrasonic scalpel to perforate the ileal muscle but not the mucosa distally, this retraction was reduced. Full details of this technique will be published elsewhere. OPERATIVE TECHNIQUES Tissue aspiration. This was simply an extension of the techniques used to aspirate cataracts using the Phaco-Emulsifier and neurosurgical techiques using the CUSA"'1 System. The tip of the ultrasonic scalpel was placed against tissue and power applied, which directly fragmented the target tissue, which was then aspirated. Slightly rotating the tip enlarged the resulting defect, and continued rotation led to gradual debulking of a solid tumor, as, for example, in rectal cancers. The depth of aspiration could be controlled by running the tip over tissue slowly in direct contact with it at all times. Tissue incision. This was achieved by running the ultrasonic scalpel hot, which occurred when irrigation was severely reduced. The cutting effect occurred when the tip was dragged repeatedly, like a knife, across the tissue, which was fairly rapidly divided with reasonable hemostasis. The hot tip had a sufficiently cauterizing effect on vessels up to 2 mm. in size to reduce bleeding. Larger vessels were not easily severed. Tissue dissection. This involved the development of a delicate surgical technique using an ultrasonic scalpel. Fortunately, tactile feedback so obviously available to the surgeon with this device because of its differential effects on solid, membranous, and vascular tissue was of considerable Bull. N.Y. Acad. Med.
911
ULTRASONIC SCALPEL
THE ULTRASONIC SCALPEL: CLINICAL EXPERIENCE Patients
Procedures
Rectal cancer Rectal villous adenoma Giant subfascial lipoma Pancreatic cancer Liver tumour Local oral lesions Extensive oral lesions
2 1 I 1 6 2 10
3 I I I 8 2 10
Totals
23
26
Diagnosis
help. Vessels and ducts could be entered if such tactile feedback was not appreciated but the probing action of the ultrasonic scalpel was easily controlled and the tip could be moved away from, or parallel to, vessels as required. This selective probing action was the key to tissue dissection. Patient procedures. At the time of writing, 23 patients have been operated on by the author and 26 procedures had been performed (see table). Before the ultrasonic scalpel was generally used on patients, however, a small pilot study was done and preoperatively the new technique was discussed with patients so that they understood what would happen to them. Protocols were then submitted with the results of the laboratory work and these pilot studies to the Research Committees of both the Veterans Administration Medical Center in the Bronx and to the Mount Sinai Medical Center in New York. After approval of these protocols, using official consent forms, clinical work continued. The aspiration technique was used only for rectal cancers, which were fixed, obstructing, and inoperable. Aspiration of the tumors effectively reduced their size, and, in a very controllable way, cored out the center, as in a standard fulguration. The incision technique was used for rectal villous adenomas and for local and extensive oral lesions. The method first defined accurately the line of excision of the tumor, and slowly then incised along this line, using an ultrasonic scalpel at maximum heat. This cauterized all small vessels, and larger ones could be secured in this way if time were taken to draw the vibrating tip across them, slowly coagulating them as they appeared. The incision was simply extended in length and depth until en bloc excision of tumor tissue was completed. The technique of dissection was used in giant subfascial lipomas, pancreas, and liver, where care was taken to react to differences in the "feel" Vol. 55, No. 10, November 1979
912
W. J. D. HODGSON HODGSON~~~~~~~~~~~~
of tissue, stopping when resistance was encountered. For example, it was easy to divide the pancreas at the neck with an ultrasonic scalpel and to free the portal vein and its small and large branches. Similarly, branches of the hepatic arteries, portal vein, and biliary system could be dissected free from mesenchymal tissue in the liver by running an ultrasonic scalpel along and parallel to the vessel. RESULTS
In animal work, results in the liver and spleen were particularly gratifying, but it was also clear that new techniques for use with the ultrasonic scalpel were necessary to maintain hemostasis. Vessels were easily exposed and tied and, as experience was gained, operative speed increased. Further, in the animal work no late bleeding occurred. Where mucosa was locally stripped from bowel, regrowth of mucosa occurred in a week. When hemihepatectomy was carried out using the ultrasonic scalpel in dogs, physiological parameters did not differ from those obtained using slower conventional techniques. Of the dogs in which partial pancreatectomy was carried out, one died of acute pancreatitis and the others survived for the six-week term of the experiment. Histological evaluation of the dog work demonstrates that the worst tissue necrosis in the early studies occurred in lung resection when the damage was up to 20 cells thick. Usually, very little tissue necrosis was evident following use of the ultrasonic scalpel. Naturally, the cut edge was not as sharp as that obtained with a steel blade, but the surfaces divided by an ultrasonic scalpel had a layer of red cells closely adherent to it, which appeared "bonded'" to it.7 Preliminary studies using mini pigs, rabbits, and dogs revealed no significant differences in the healing of abdominal incisions made using cautery, a steel blade, and an ultrasonic scalpel.8 Femoral vessels and nerves in dogs could be dissected more rapidly using an ultrasonic scalpel than by conventional techniques and without significant histological damage as compared to the controls.9 The immediate postoperative course following mucosal proctectomy was slow. Dogs lost weight initially and had frequent but controllable stools. Within two weeks they had stabilized and within two months were producing between two and six solid or semisolid stools daily. During our follow-up period of up to 10 months, this satisfactory state of affairs appeared to endure. The ultrasonic aspiration, or "fulguration," of rectal cancers presented Bull. N.Y. Acad. Med.
ULTRASONIC SCALPEL
913 913
no difficulty. Precise amounts of tumor could be removed speedily and without significant blood loss. In my experience using electrocoagulation, removal of an obstructing tumor of the rectum was probably a little slower than with an ultrasonic scalpel. The postoperative course was satisfactory, and no late bleeding was encountered after using the new device. In oral surgery, the cutting technique, once learned, speeded up extensive dissections. At the Bronx Veterans Administration Medical Center, three partial glossectomies, five hemiglossectomies, and two three quarter glossectomies were successfully performed without blood transfusion, charring, or subsequent tongue necrosis but with accurate tumor excision because the anatomy of the surgical field could be so clearly defined. The ultrasonic scalpel was of excellent value in dissecting out a giant subfascial lipoma in a Jehovah's Witness. Because feeding vessels came from beneath the inguinal ligament, it was imperative that they were not accidental.ly severed. Demonstration by and slow cautery with an ultrasonic scalpel proved quite successful. In the pancreas'0 and liver" the device gave the surgeon added confidence during major procedures as the dissection proceeded, and as more cases were done. Initially, there may be a clumsy feel but this was soon dispelled as the method of dissection became more familiar. Mainly, of course, proper positioning of the surgeon, adequate exposure of the organ, and gentle handling of the instrument, without rushing, have been most important. DISCUSSION
The ultrasonic scalpel has proved to be an exciting experimental tool. Its precursor, the Phaco-Emulsifier, is widely used in ophthalmology3 and, as an aspirating device, the CUSA'"`1' System is in use in neurosurgery.4 Work in our laboratories has demonstrated that it can be used effectively in the thorax and abdomen, with particular emphasis on liver and spleen resection and pancreatic and mucosal stripping. Clinically, this instrument seems to have a place in surgery. Ransohoff now uses the device regularly in neurosurgery, employing techniques he and Flamm described.4 It seems quite safe in neurosurgery. Similarly, the lack of operative and postoperative complications in general surgery suggests its safety in this field. It has advantages over cryosurgical techniques in that the tip does not stick to tissue, no late oozing of divided surfaces occurs, and an ultrasonic scalpel does not need the wide access necessary for cryosurgery. It would seem that more control is available with an ultrasonic scalpel than with a Vol. 55, No. 10, November 1979
914
W. J. D. HODGSON
cryogenic probe. The laser appears to be an excellent rapid method to carry out superficial excision of tissue, but it gives the surgeon no tactile feedback and is indiscriminate in its vaporization of tissue. Hence large vessels may be easily divided and the resulting bleeding neutralize the laser beam, even if defocused to provide cautery. With an ultrasonic scalpel, vessels may be secured before they bleed and delicate resections can be carried out, although a direct attack on a vessel would, of course, puncture it. Because accurate removal of tumor tissue from the rectum is easily carried out, we shall continue using the device to treat these inoperable cases. Similarly, it will continue to be useful in excision of villous adenomas. The dog work in mucosal proctectomy and the continent result of the endorectal pull through has been so encouraging that it is intended to use exactly the same technique in patients with ulcerative colitis. The ultrasonic scalpel improved the surgeon's ability to dissect the pancreas off the portal vein, but dissection of the duct from the acinar tissue is more difficult in patients. In the liver, wedge resection of tumor has become a safe and simple procedure even when the resection is extensive. It is intended to continue its use routinely in liver surgery at the Mount Sinai Medical Center. My colleagues in the head and neck field now feel that the ultrasonic scalpel is a necessity rather than a luxury because it is possible to perform almost bloodless surgery of the tongue for extensive oral tumors.'2
CONCLUSION
Continuing laboratory and clinical work demonstrates that three techniques are available to the surgeon for use with the ultrasonic scalpel: tissue aspiration, incision, and dissection. Extensive animal work has demonstrated the range of this instrument from bloodless mucosal proctectomy to hemihepatectomy and permitted work to proceed, with adequate review, in the clinical field. Twenty-six procedures have been carried out in 23 patients and the ultrasonic scalpel has shown value in surgery of the tongue, the liver, the pancreas, and the rectum. It also appears experimentally useful for partial splenectomy, partial pneumonectomy, flap dissection, and mucosal proctectomy and endorectal pull through with anal continence. Its clinical use continues.
Bull. N.Y. Acad. Med.
ULTRASONIC SCALPEL
915
ACKNOWLEDGEMENTS
I thank my colleagues in the Departments of Surgery at the Bronx Veterans Administration Medical Center and the Mount Sinai Hospital for their encouragement in the use of the ultrasonic scalpel. Thanks are also due to Dr. Joseph Williams for his histological studies and to Mr. Winkfield and his staff in the Surgical Research Laboratories of the Bronx Veterans Administration Medical Center and Mr. Wallen and his staff in the Mount Sinai School of Medicine Surgical Research Laboratories. REFERENCES 1. Kelman, C. D.: Phaco emulsification and aspiration. Am. J. Ophthalmol. 67:464-77, 1969. 2. Kelman, C. D.: Phaco emulsification and aspiration-A report of 500 consecutive cases. Am. J. Ophthalmol. 75:764-68, 1973. 3. Jaffe, N. S.: Current concepts in ophthalmology. Cataract surgery-A modern attitude toward a technologic explosion. N. Engl. J. Med. 299:23537, 1978. 4. Flamm, E. S., Ransohoff, J., Wunchinich, D., and Broadwin, A.: Preliminary experience with ultrasonic aspiration in neurosurgery. Neurosurgery 2:240-45, 1978. 5. Hodgson, W. J. B., Poddar, P. K., Mencer, E. J., et al: Evaluation of ultrasonically powered instruments in the laboratory and in the clinical setting. Am. J. Gastroent. In press. 6. Hodgson, W. J. B., Poddar, P. K., Weitz, J., et al: The Cavitron Ultrasonically Powered Aspiration Device (CUSA"' I System): An Instrument Used for Selective Dissection of Blood Vessels. In: General Microsurgery. New
Vol. 55, No. 10, November 1979
York, Houghton, Mifflin. In press. 7. Williams, J. W. and Hodgson, W. J. B.: Histological evaluation of tissue sectioned by ultrasonically powered instruments (A preliminary report). Mt. Sinai J. Med. 46:105-06, 1979. 8. Herte, M. C., and Horton, C. E.: Preliminary Report. Comparative Wound Healing in Animal Subjects Using the CUSAIN' System Versus Conventional Surgical Instruments. Unpublished data. 9. Chiuten, M. F., Baek, S-M., Lawson, W., et al.: CUSATm System: New Tool for Plastic Surgery. Unpublished data. 10. Hodgson, W. J. B., Bakare, S., Harrington, E., et al.: General surgical evaluation of a powered device operating at ultrasonic frequencies. Mt. Sinai J. Med. 46:99-103, 1979. 11. Hodgson, W. J. B. and Aufses, A.: Surgical ultrasonic dissection of the liver. Surg. Rounds. 68-72, August 1979. 12. Weitz, J., Hodgson, W. J. B., Loscalzo, L. J., and McElhinney, A. J.: A bloodless technique for tongue surgery. 25th Annual Meeting ofthe Society of Head & Neck Surgeons. Pittsburgh, April 1979.
THE ULTRASONIC SCALPEL* W. JOHN B. HODGSON, M.S., F.R.C.S. Assistant Professor of Surgery The Mount Sinai School of Medicine of the City University of New York New York, New York Assistant Chief, Surgical Service Veterans Administration Medical Center Bronx, New York
DNURING the past two years the author has explored surgical techniques with the ultrasonic scalpel. Early dog studies ascertained in which tissues this instrument would be useful, and three operative techniques were devised: tissue aspiration, tissue incision and tissue dissection. Continuing laboratory and clinical work showed the potential value of the ultrasonic scalpel in reducing blood loss in oral, hepatic, and pancreatic surgery, partial splenectomy and pneumonectomy, flap dissection, dissection of solid tumors, fulguration of rectal cancers, and mucosal proctectomy. MATERIALS AND METHODS
The ultrasonic scalpel. The device is a logical development of the Cavitron-Kelman Phaco-Emulsifier"1' which is in general use for cataract surgery '2 and the preferred method in many centers.3 In February 1976 the Cavitron Ultrasonic Aspiration Device (CUSAT'N System), a larger and more powerful instrument than the Phaco-Emulsifier, was used, with favorable results, to aspirate neurogenic tumors.4 In the Surgical Research Laboratories of the Bronx Veterans Administration Medical Center and subsequently clinically, the CUSAT1i System was examined, evaluated, and successfully used as an ultrasonic scalpel in general surgery.5 The ultrasonic scalpel consists of a power and control console, and requires only standard operating room electrical connections to which a gas sterilizable handpiece is connected. In neurosurgery a pistol grip is used,4 but for general surgery the pencil grip is preferred.5 i; Briefly, the handpiece is constructed with a stainless steel water cooled jacket inside of which is a magneto strictive device attached by a connecting body to a *Presented before the Section on Surgery of the New York Academy of Medicine May 8, 1979. Address for reprint requests: 43-30 38th Street, Long Island City, N.Y. 11101.
Bull. N.Y. Acad. Med.
~
~
~
ULTRASONIC SCALPEL LRSNCS
909
cone-shaped titanium amplifier, only 2 mm. wide at its open tip. The titanium amplifier is housed in a plastic flue except for. the last 4 mm. of the tip. The action of the ultrasonic scalpel depends on resonant vibration of the magneto strictive transducers. These are simply long metal structures which vibrate longitudinally in response to an alternating electric current of exactly the frequency required to produce such vibration, which is passed through a coil around them. When the electric coil is activated, contraction and expansion of the magneto strictive transducers and of the cone shaped amplifier tip follows. Each contraction and expansion occurs about the resting position, with a maximum excursion of 150 microns, resulting in a total stroke of 300 microns. This ultrasonic vibration is quite unlike that of reciprocating cutting devices, nonuniform and remarkable for the very high velocities achieved at the extremes of movement. Hence tissue within a 1 mm. or 2 mm. radius from the tip is disrupted and aspirated. A technician sets up the instrument and controls the ultrasonic power available in the handpiece. When low power is used, minimal tissue fragmentation occurs. Tissue with a high water content is disrupted and other tissues, such as blood vessels, left intact. When high power is used, fragmentation is more rapid, and, despite the high collagen content of blood vessels, carelessness results in easily puncturing them. The technician also controls irrigation and aspiration rates. Low irrigation rates are used when heat is required at the tip for cautery. Because aspiration tubing cannot be cleaned, a new CUSA PAK"-' is required for each procedure. This fresh sterile tubing connects the handpiece to the console, and requires a technician or nurse to plug it into the console, after which the surgeon can commence the procedure. Animal work. Initial work with dogs5 demonstrated that the ultrasonic scalpel can perform a liver biopsy directly, without catgut hemostatic sutures, and in fact established that the liver parenchyma was removed but the vessels were not. These were easily tied and biopsies could be taken bloodlessly and quickly, findings more than adequately confirmed in baboons. It was also established that the dog spleen can be divided using the ultrasonic scalpel and bleeding prevented by tying vascular bundles exposed during the incision. In the abdomen, division of the stomach or bowel wall was slow and unsatisfactory, but it was relatively easy to strip antral mucosa or small bowel mucosa directly from submucosa and muscle. In addition, lung tissue could be divided and apparently sealed. On the Vol. 55, No. 10, November 1979
910
W. J. W. J. D. D. HODGSON HODGSON
other hand, partial nephrectomy did not prove to be a bloodless procedure. More extensive experimental operative procedures were then carried out using an ultrasonic scalpel.6 Hemihepatectomy could be performed with despatch, and pancreatic acinar tissue could be stripped from the pancreatic duct of a dog, which, although only 1 mm. wide, could be left intact. This was accomplished in a series of five dogs for 3 cm. to 4 cm., leaving normal pancreatic tissue proximal and distal to the stripped duct. Because mucosal stripping appeared to be a simple procedure by direct application of an ultrasonic scalpel to bowel mucosa, a study was set up, which continues, to test the feasibility of mucosal proctectomy and endorectal pull through in dogs. This has been performed with minimal blood loss on 17 dogs to date and all have been continent of stool postoperatively. Adequate adherence has been obtained between the serosa of the ileum and denuded rectal submucosa, although in earlier cases some retraction occurred. Later, using an ultrasonic scalpel to perforate the ileal muscle but not the mucosa distally, this retraction was reduced. Full details of this technique will be published elsewhere. OPERATIVE TECHNIQUES Tissue aspiration. This was simply an extension of the techniques used to aspirate cataracts using the Phaco-Emulsifier and neurosurgical techiques using the CUSA"'1 System. The tip of the ultrasonic scalpel was placed against tissue and power applied, which directly fragmented the target tissue, which was then aspirated. Slightly rotating the tip enlarged the resulting defect, and continued rotation led to gradual debulking of a solid tumor, as, for example, in rectal cancers. The depth of aspiration could be controlled by running the tip over tissue slowly in direct contact with it at all times. Tissue incision. This was achieved by running the ultrasonic scalpel hot, which occurred when irrigation was severely reduced. The cutting effect occurred when the tip was dragged repeatedly, like a knife, across the tissue, which was fairly rapidly divided with reasonable hemostasis. The hot tip had a sufficiently cauterizing effect on vessels up to 2 mm. in size to reduce bleeding. Larger vessels were not easily severed. Tissue dissection. This involved the development of a delicate surgical technique using an ultrasonic scalpel. Fortunately, tactile feedback so obviously available to the surgeon with this device because of its differential effects on solid, membranous, and vascular tissue was of considerable Bull. N.Y. Acad. Med.
911
ULTRASONIC SCALPEL
THE ULTRASONIC SCALPEL: CLINICAL EXPERIENCE Patients
Procedures
Rectal cancer Rectal villous adenoma Giant subfascial lipoma Pancreatic cancer Liver tumour Local oral lesions Extensive oral lesions
2 1 I 1 6 2 10
3 I I I 8 2 10
Totals
23
26
Diagnosis
help. Vessels and ducts could be entered if such tactile feedback was not appreciated but the probing action of the ultrasonic scalpel was easily controlled and the tip could be moved away from, or parallel to, vessels as required. This selective probing action was the key to tissue dissection. Patient procedures. At the time of writing, 23 patients have been operated on by the author and 26 procedures had been performed (see table). Before the ultrasonic scalpel was generally used on patients, however, a small pilot study was done and preoperatively the new technique was discussed with patients so that they understood what would happen to them. Protocols were then submitted with the results of the laboratory work and these pilot studies to the Research Committees of both the Veterans Administration Medical Center in the Bronx and to the Mount Sinai Medical Center in New York. After approval of these protocols, using official consent forms, clinical work continued. The aspiration technique was used only for rectal cancers, which were fixed, obstructing, and inoperable. Aspiration of the tumors effectively reduced their size, and, in a very controllable way, cored out the center, as in a standard fulguration. The incision technique was used for rectal villous adenomas and for local and extensive oral lesions. The method first defined accurately the line of excision of the tumor, and slowly then incised along this line, using an ultrasonic scalpel at maximum heat. This cauterized all small vessels, and larger ones could be secured in this way if time were taken to draw the vibrating tip across them, slowly coagulating them as they appeared. The incision was simply extended in length and depth until en bloc excision of tumor tissue was completed. The technique of dissection was used in giant subfascial lipomas, pancreas, and liver, where care was taken to react to differences in the "feel" Vol. 55, No. 10, November 1979
912
W. J. D. HODGSON HODGSON~~~~~~~~~~~~
of tissue, stopping when resistance was encountered. For example, it was easy to divide the pancreas at the neck with an ultrasonic scalpel and to free the portal vein and its small and large branches. Similarly, branches of the hepatic arteries, portal vein, and biliary system could be dissected free from mesenchymal tissue in the liver by running an ultrasonic scalpel along and parallel to the vessel. RESULTS
In animal work, results in the liver and spleen were particularly gratifying, but it was also clear that new techniques for use with the ultrasonic scalpel were necessary to maintain hemostasis. Vessels were easily exposed and tied and, as experience was gained, operative speed increased. Further, in the animal work no late bleeding occurred. Where mucosa was locally stripped from bowel, regrowth of mucosa occurred in a week. When hemihepatectomy was carried out using the ultrasonic scalpel in dogs, physiological parameters did not differ from those obtained using slower conventional techniques. Of the dogs in which partial pancreatectomy was carried out, one died of acute pancreatitis and the others survived for the six-week term of the experiment. Histological evaluation of the dog work demonstrates that the worst tissue necrosis in the early studies occurred in lung resection when the damage was up to 20 cells thick. Usually, very little tissue necrosis was evident following use of the ultrasonic scalpel. Naturally, the cut edge was not as sharp as that obtained with a steel blade, but the surfaces divided by an ultrasonic scalpel had a layer of red cells closely adherent to it, which appeared "bonded'" to it.7 Preliminary studies using mini pigs, rabbits, and dogs revealed no significant differences in the healing of abdominal incisions made using cautery, a steel blade, and an ultrasonic scalpel.8 Femoral vessels and nerves in dogs could be dissected more rapidly using an ultrasonic scalpel than by conventional techniques and without significant histological damage as compared to the controls.9 The immediate postoperative course following mucosal proctectomy was slow. Dogs lost weight initially and had frequent but controllable stools. Within two weeks they had stabilized and within two months were producing between two and six solid or semisolid stools daily. During our follow-up period of up to 10 months, this satisfactory state of affairs appeared to endure. The ultrasonic aspiration, or "fulguration," of rectal cancers presented Bull. N.Y. Acad. Med.
ULTRASONIC SCALPEL
913 913
no difficulty. Precise amounts of tumor could be removed speedily and without significant blood loss. In my experience using electrocoagulation, removal of an obstructing tumor of the rectum was probably a little slower than with an ultrasonic scalpel. The postoperative course was satisfactory, and no late bleeding was encountered after using the new device. In oral surgery, the cutting technique, once learned, speeded up extensive dissections. At the Bronx Veterans Administration Medical Center, three partial glossectomies, five hemiglossectomies, and two three quarter glossectomies were successfully performed without blood transfusion, charring, or subsequent tongue necrosis but with accurate tumor excision because the anatomy of the surgical field could be so clearly defined. The ultrasonic scalpel was of excellent value in dissecting out a giant subfascial lipoma in a Jehovah's Witness. Because feeding vessels came from beneath the inguinal ligament, it was imperative that they were not accidental.ly severed. Demonstration by and slow cautery with an ultrasonic scalpel proved quite successful. In the pancreas'0 and liver" the device gave the surgeon added confidence during major procedures as the dissection proceeded, and as more cases were done. Initially, there may be a clumsy feel but this was soon dispelled as the method of dissection became more familiar. Mainly, of course, proper positioning of the surgeon, adequate exposure of the organ, and gentle handling of the instrument, without rushing, have been most important. DISCUSSION
The ultrasonic scalpel has proved to be an exciting experimental tool. Its precursor, the Phaco-Emulsifier, is widely used in ophthalmology3 and, as an aspirating device, the CUSA'"`1' System is in use in neurosurgery.4 Work in our laboratories has demonstrated that it can be used effectively in the thorax and abdomen, with particular emphasis on liver and spleen resection and pancreatic and mucosal stripping. Clinically, this instrument seems to have a place in surgery. Ransohoff now uses the device regularly in neurosurgery, employing techniques he and Flamm described.4 It seems quite safe in neurosurgery. Similarly, the lack of operative and postoperative complications in general surgery suggests its safety in this field. It has advantages over cryosurgical techniques in that the tip does not stick to tissue, no late oozing of divided surfaces occurs, and an ultrasonic scalpel does not need the wide access necessary for cryosurgery. It would seem that more control is available with an ultrasonic scalpel than with a Vol. 55, No. 10, November 1979
914
W. J. D. HODGSON
cryogenic probe. The laser appears to be an excellent rapid method to carry out superficial excision of tissue, but it gives the surgeon no tactile feedback and is indiscriminate in its vaporization of tissue. Hence large vessels may be easily divided and the resulting bleeding neutralize the laser beam, even if defocused to provide cautery. With an ultrasonic scalpel, vessels may be secured before they bleed and delicate resections can be carried out, although a direct attack on a vessel would, of course, puncture it. Because accurate removal of tumor tissue from the rectum is easily carried out, we shall continue using the device to treat these inoperable cases. Similarly, it will continue to be useful in excision of villous adenomas. The dog work in mucosal proctectomy and the continent result of the endorectal pull through has been so encouraging that it is intended to use exactly the same technique in patients with ulcerative colitis. The ultrasonic scalpel improved the surgeon's ability to dissect the pancreas off the portal vein, but dissection of the duct from the acinar tissue is more difficult in patients. In the liver, wedge resection of tumor has become a safe and simple procedure even when the resection is extensive. It is intended to continue its use routinely in liver surgery at the Mount Sinai Medical Center. My colleagues in the head and neck field now feel that the ultrasonic scalpel is a necessity rather than a luxury because it is possible to perform almost bloodless surgery of the tongue for extensive oral tumors.'2
CONCLUSION
Continuing laboratory and clinical work demonstrates that three techniques are available to the surgeon for use with the ultrasonic scalpel: tissue aspiration, incision, and dissection. Extensive animal work has demonstrated the range of this instrument from bloodless mucosal proctectomy to hemihepatectomy and permitted work to proceed, with adequate review, in the clinical field. Twenty-six procedures have been carried out in 23 patients and the ultrasonic scalpel has shown value in surgery of the tongue, the liver, the pancreas, and the rectum. It also appears experimentally useful for partial splenectomy, partial pneumonectomy, flap dissection, and mucosal proctectomy and endorectal pull through with anal continence. Its clinical use continues.
Bull. N.Y. Acad. Med.
ULTRASONIC SCALPEL
915
ACKNOWLEDGEMENTS
I thank my colleagues in the Departments of Surgery at the Bronx Veterans Administration Medical Center and the Mount Sinai Hospital for their encouragement in the use of the ultrasonic scalpel. Thanks are also due to Dr. Joseph Williams for his histological studies and to Mr. Winkfield and his staff in the Surgical Research Laboratories of the Bronx Veterans Administration Medical Center and Mr. Wallen and his staff in the Mount Sinai School of Medicine Surgical Research Laboratories. REFERENCES 1. Kelman, C. D.: Phaco emulsification and aspiration. Am. J. Ophthalmol. 67:464-77, 1969. 2. Kelman, C. D.: Phaco emulsification and aspiration-A report of 500 consecutive cases. Am. J. Ophthalmol. 75:764-68, 1973. 3. Jaffe, N. S.: Current concepts in ophthalmology. Cataract surgery-A modern attitude toward a technologic explosion. N. Engl. J. Med. 299:23537, 1978. 4. Flamm, E. S., Ransohoff, J., Wunchinich, D., and Broadwin, A.: Preliminary experience with ultrasonic aspiration in neurosurgery. Neurosurgery 2:240-45, 1978. 5. Hodgson, W. J. B., Poddar, P. K., Mencer, E. J., et al: Evaluation of ultrasonically powered instruments in the laboratory and in the clinical setting. Am. J. Gastroent. In press. 6. Hodgson, W. J. B., Poddar, P. K., Weitz, J., et al: The Cavitron Ultrasonically Powered Aspiration Device (CUSA"' I System): An Instrument Used for Selective Dissection of Blood Vessels. In: General Microsurgery. New
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York, Houghton, Mifflin. In press. 7. Williams, J. W. and Hodgson, W. J. B.: Histological evaluation of tissue sectioned by ultrasonically powered instruments (A preliminary report). Mt. Sinai J. Med. 46:105-06, 1979. 8. Herte, M. C., and Horton, C. E.: Preliminary Report. Comparative Wound Healing in Animal Subjects Using the CUSAIN' System Versus Conventional Surgical Instruments. Unpublished data. 9. Chiuten, M. F., Baek, S-M., Lawson, W., et al.: CUSATm System: New Tool for Plastic Surgery. Unpublished data. 10. Hodgson, W. J. B., Bakare, S., Harrington, E., et al.: General surgical evaluation of a powered device operating at ultrasonic frequencies. Mt. Sinai J. Med. 46:99-103, 1979. 11. Hodgson, W. J. B. and Aufses, A.: Surgical ultrasonic dissection of the liver. Surg. Rounds. 68-72, August 1979. 12. Weitz, J., Hodgson, W. J. B., Loscalzo, L. J., and McElhinney, A. J.: A bloodless technique for tongue surgery. 25th Annual Meeting ofthe Society of Head & Neck Surgeons. Pittsburgh, April 1979.
