Automatically irrigated bipolar forceps Technical note
MANUEL DUSOVNV, M.D., RAN VAS, PH.D., CAnROLL P. OSCOOD, M.D., JOSEPH C. MAROON, M.D., AND PETER J. JANETTA, M.D. Department of Neurological Surgery, University of Pittsburgh, and School of Medicine and Biotechnology Program, Carnegie-Mellon University, Pittsburgh, Pennsylvania The authors describe a newly developed automatically irrigated bipolar forceps with controlled irrigation pressure. KEY WORDS 9 bipolar forceps 9 pressure p u m p e l e c t r o m a g n e t i c valve 9 instrumentation
HE bipolar coagulator is one of the most useful instruments presently available to the microneurosurgeon. However, commercially available instruments are far from ideal. To avoid tissue charring the forceps tips have been insulated, which at the same time limits coagulation. Frequent manual irrigation of the work area helps to prevent tissue heating, but this can be technically cumbersome.3,6 A thermistorregulated bipolar forceps was recently described by Sugita and Tsugane) and although this may minimize local overheating or sparking, irrigation is still necessary. Greenwood 1 and later Scarp developed suction-irrigation forceps, but the irrigation was not automatically controlled. King and Worpole 2 developed a continuous saline drip irrigator, but this system has significant disadvantages, including continuous saline flow even when the bipolar coagulator is not in use; moreover, the rate of irrigation is difficult to adjust. Ideally, since the bipolar forceps may be used at vertical angles (posterior fossa), vigorous irrigation pressure
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will be desirable at times. This is not available in existing forceps. This note describes an automatically irrigated bipolar forceps. Irrigation pressure may be precisely adjusted, and adequate irrigation is supplied regardless of forceps position. Description
The automatically irrigated bipolar forceps system* has four parts: a pressure pump, an electromagnetic valve, a tubing system, and an irrigating bipolar forceps. The pressure pump (Fig. 1) is divided into two parts: a plexiglass base housing a 250-cc disposable saline bag, and a plexiglass cover which is compressed by stainless steel springs, by way of an adjustable screw. The electromagnetic valve (Fig. 1 upper) has three parts: the electromagnet, a power *Bipolar forceps can be obtained from Ran Vas, Ph.D., School of Medicine and Biotechnology Program, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213. J. Neurosurg. / Volume 43 / October, 1975
Automatically irrigated bipolar forceps supply controlled by the foot switch of the bipolar unit, and an outside clamp-type valve connected mechanically to the electromagnet. The tubing system (Fig. 1 upper) is composed of a long polyvinylchloride tube with a 5-mm bore, intravenous infusion roller clamp, and a syringe infusion fitting. The tubing directly under the electromagnetic clamps is an interposed segment of rubber tubing 6 mm in diameter and 5 cm long; this allows occlusion of saline flow when the coagulator is not in use. A roller-type intravenous clamp installed 30 cm from the forceps permits a finer adjustment of the saline flow. One end of the tubing is connected to the saline bag, and the other is attached to the forceps by the syringe fitting. The irrigating forceps were constructed from ordinary microbayonet or jewelers forceps (Fig. 2). One arm of the forceps was cut off approximately 40 mm from the tip. A stainless steel 18-gauge tube was welded to the inside of this arm, and thus the tip of this tube became the tip of the forceps. The tip was filed down to a very sharp angle, so that the opening was no longer in the shape of an elipse; this prevents any blocking of the irrigating tube. The tube was then reshaped to match the other arm of the forceps. The blunt edges of the two arms were encapsulated with epoxy resin, together with a needle connector which was attached to the stainless steel tube. The automatically irrigated bipolar forceps system outlined here is an integral part of the bipolar forceps, and can be gas sterilized. These self-irrigating bipolar forceps have been of great technical value in patients operated on for intramedullary, cerebral, posterior fossa, and intraorbital tumors, and arteriovenous malformations. Forceps tip charring and secondary tissue adherence are minimal, and operative time is significantly reduced.
Acknowledgment We wish to acknowledge the expert help and advice received from the Medical Illustration Department, Oakland Veterans Administration Hospital, Pittsburgh, Pennsylvania. References 1. Greenwood J Jr: Two point or interpolar coagulation: review after a twelve year period with notes on addition of a sucker tip. J Neurosurg 12:196-197, 1955 2. King TT, Worpole R: Self-irrigating bipolar J. Neurosurg. / Volume 43 / October, 1975
FIG. 1. Photograph of the apparatus. 1 bipolar unit; 2 --= electromagnetic valve; 3 -power supply; 4 = electromagnet; 5 -- foot switch; 6 = pressure pump; 7 ~ tube and saline bag; 8 = screw for compressing bag.
Fro. 2. Bipolar irrigating bayonet forceps.
3.
4. 5. 6.
diathermy forceps: technical note. J Nenrosurg 37:246-247, 1972 Malis LI: Bipolar coagulation in microsurgery in Donaghy RMP, Yasargil MG (eds): MicroVascular Surgery. Stuttgart, Georg Thieme Verlag, 1967 Scarf TB: A new bipolar suction-cautery forceps for micro-neurosurgical use. Surg Neurol 2:213, 1974 Sugita K, Tsugane R: Bipolar coagulator with automatic thermocontrol. Technical note. J Neurosurg 41:777-779, 1974 Yasargil MG: Microsurgery Applied to Neurosurgery. Stuttgart, George Thieme Verlag, 1969
/lddress reprint requests to: Manuel Dujovny, M.D., Department of Neurological Surgery, University of Pittsburgh School of Medicine, Oakland VA Hospital, University Drive C, Pittsburgh, Pennsylvania 15240.
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MANUEL DUSOVNV, M.D., RAN VAS, PH.D., CAnROLL P. OSCOOD, M.D., JOSEPH C. MAROON, M.D., AND PETER J. JANETTA, M.D. Department of Neurological Surgery, University of Pittsburgh, and School of Medicine and Biotechnology Program, Carnegie-Mellon University, Pittsburgh, Pennsylvania The authors describe a newly developed automatically irrigated bipolar forceps with controlled irrigation pressure. KEY WORDS 9 bipolar forceps 9 pressure p u m p e l e c t r o m a g n e t i c valve 9 instrumentation
HE bipolar coagulator is one of the most useful instruments presently available to the microneurosurgeon. However, commercially available instruments are far from ideal. To avoid tissue charring the forceps tips have been insulated, which at the same time limits coagulation. Frequent manual irrigation of the work area helps to prevent tissue heating, but this can be technically cumbersome.3,6 A thermistorregulated bipolar forceps was recently described by Sugita and Tsugane) and although this may minimize local overheating or sparking, irrigation is still necessary. Greenwood 1 and later Scarp developed suction-irrigation forceps, but the irrigation was not automatically controlled. King and Worpole 2 developed a continuous saline drip irrigator, but this system has significant disadvantages, including continuous saline flow even when the bipolar coagulator is not in use; moreover, the rate of irrigation is difficult to adjust. Ideally, since the bipolar forceps may be used at vertical angles (posterior fossa), vigorous irrigation pressure
T
502
9
will be desirable at times. This is not available in existing forceps. This note describes an automatically irrigated bipolar forceps. Irrigation pressure may be precisely adjusted, and adequate irrigation is supplied regardless of forceps position. Description
The automatically irrigated bipolar forceps system* has four parts: a pressure pump, an electromagnetic valve, a tubing system, and an irrigating bipolar forceps. The pressure pump (Fig. 1) is divided into two parts: a plexiglass base housing a 250-cc disposable saline bag, and a plexiglass cover which is compressed by stainless steel springs, by way of an adjustable screw. The electromagnetic valve (Fig. 1 upper) has three parts: the electromagnet, a power *Bipolar forceps can be obtained from Ran Vas, Ph.D., School of Medicine and Biotechnology Program, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213. J. Neurosurg. / Volume 43 / October, 1975
Automatically irrigated bipolar forceps supply controlled by the foot switch of the bipolar unit, and an outside clamp-type valve connected mechanically to the electromagnet. The tubing system (Fig. 1 upper) is composed of a long polyvinylchloride tube with a 5-mm bore, intravenous infusion roller clamp, and a syringe infusion fitting. The tubing directly under the electromagnetic clamps is an interposed segment of rubber tubing 6 mm in diameter and 5 cm long; this allows occlusion of saline flow when the coagulator is not in use. A roller-type intravenous clamp installed 30 cm from the forceps permits a finer adjustment of the saline flow. One end of the tubing is connected to the saline bag, and the other is attached to the forceps by the syringe fitting. The irrigating forceps were constructed from ordinary microbayonet or jewelers forceps (Fig. 2). One arm of the forceps was cut off approximately 40 mm from the tip. A stainless steel 18-gauge tube was welded to the inside of this arm, and thus the tip of this tube became the tip of the forceps. The tip was filed down to a very sharp angle, so that the opening was no longer in the shape of an elipse; this prevents any blocking of the irrigating tube. The tube was then reshaped to match the other arm of the forceps. The blunt edges of the two arms were encapsulated with epoxy resin, together with a needle connector which was attached to the stainless steel tube. The automatically irrigated bipolar forceps system outlined here is an integral part of the bipolar forceps, and can be gas sterilized. These self-irrigating bipolar forceps have been of great technical value in patients operated on for intramedullary, cerebral, posterior fossa, and intraorbital tumors, and arteriovenous malformations. Forceps tip charring and secondary tissue adherence are minimal, and operative time is significantly reduced.
Acknowledgment We wish to acknowledge the expert help and advice received from the Medical Illustration Department, Oakland Veterans Administration Hospital, Pittsburgh, Pennsylvania. References 1. Greenwood J Jr: Two point or interpolar coagulation: review after a twelve year period with notes on addition of a sucker tip. J Neurosurg 12:196-197, 1955 2. King TT, Worpole R: Self-irrigating bipolar J. Neurosurg. / Volume 43 / October, 1975
FIG. 1. Photograph of the apparatus. 1 bipolar unit; 2 --= electromagnetic valve; 3 -power supply; 4 = electromagnet; 5 -- foot switch; 6 = pressure pump; 7 ~ tube and saline bag; 8 = screw for compressing bag.
Fro. 2. Bipolar irrigating bayonet forceps.
3.
4. 5. 6.
diathermy forceps: technical note. J Nenrosurg 37:246-247, 1972 Malis LI: Bipolar coagulation in microsurgery in Donaghy RMP, Yasargil MG (eds): MicroVascular Surgery. Stuttgart, Georg Thieme Verlag, 1967 Scarf TB: A new bipolar suction-cautery forceps for micro-neurosurgical use. Surg Neurol 2:213, 1974 Sugita K, Tsugane R: Bipolar coagulator with automatic thermocontrol. Technical note. J Neurosurg 41:777-779, 1974 Yasargil MG: Microsurgery Applied to Neurosurgery. Stuttgart, George Thieme Verlag, 1969
/lddress reprint requests to: Manuel Dujovny, M.D., Department of Neurological Surgery, University of Pittsburgh School of Medicine, Oakland VA Hospital, University Drive C, Pittsburgh, Pennsylvania 15240.
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