J Neurosurg 51:417-419, 1979
Counter-pressure mierofork for intracranial vascular anastomosis Technical note
MILTON D. HEIFETZ, M . D .
Department of Neurological Surgery, University of Southern California School of Medicine, Los Angeles, California w' A technique is described using a counter-pressure device in suturing for superficial temporal-middle cerebral artery anastomoses. KEY WORDS instrumentation
HE counter-pressure fork has been used for vascular surgery by Jacobson and others since 1962,~' but forks small enough to function easily during 1-mm vessel anastomoses have not been readily available. In 1967, YasargiP referred to Jacobson's commercially available instruments, and described an "individually manufactured... counter-presser made out of a fine needle." Subsequently, Yasargil6 discussed the use and advantages of a microfork. Small twisted wire loops 1 have been made to serve as a counter-pressure device, but the loop has the disadvantage of being difficult to disengage from the tip of the needle once the needle has been inserted into it. In performing the last 22 superficial temporal artery-middle cerebral artery (STA-MCA) anastomoses, we have used a microfork* which was specifically designed for the procedure (Fig. 1). The slot is wide enough to allow a 150-/x needle to slip between the prongs. The advantages of using a counter-pressure device include more precise needle insertion, elimination of the risk of involving the opposite wall of the vessel, decreased trauma to the intima, and the elimination of the need of an internal stent.
*Microfork manufactured by Week Corp., Research Triangle Park, North Carolina.
J. Neurosurg. / Volume 51 / September, 1979
9 microvascular surgery
After the end stay sutures have been placed, it is usually easier to first suture the far side of the anastomosis (Fig. 2 a). The microfork is first inserted within the lumen of the cortical vessel. One then slightly elevates the edge of the vessel wall, which immediately separates the two walls of the vessel. Then locate the point for needle insertion and insert the needle while opposing its downward thrust with the microfork. As the needle point passes through the vessel wall between the prongs of the microfork, deliver and expose the tip of the needle by minimally rotating the needle holder, thereby bringing the needle tip to the surface in the space between the edges of the cortical and donor vessels. Disengage the fork from the lumen of the cortical vessel and finger rotate the fork while simultaneously tilting the left hand (assuming a right-handed operator) slightly away from yourself, thereby inserting the fork into the lumen of the donor vessel to the second position (Fig. 2 b). Slightly lift the wall of the donor vessel. This opens the lumen of the STA and permits the tip of the needle to be safely passed into the lumen of the donor artery. Estimate the point of needle insertion and insert the needle into the intima of the artery next to, but not through, the microfork slot. Stop the needle movement at this point, remove the fork from the lumen, and place it on the surface of the donor artery (Fig. 2 c) to oppose the upward thrust of the needle point 4] 7
M. D. Heifetz
Fro. I. Microfork with magnified view of the tipped configuration.
FIG. 2. Operative drawings showing the four positions of the microfork during the anastomosis.
J. Neurosurg. / Volume51 / September, 1979
N e w d e v i c e for i n t r a c r a n i a l vascular a n a s t o m o s i s rubber dam (fourth position). This straddle permits the suture to be pulled through with minimal tension on the suture line. Continue to pull the suture through until the end comes into view as the suture unfolds itself, passing through the tunnel created by the fork against the rubber dam. Replace the fork with the
scissors in the left hand and cut the suture. Repeat these maneuvers until all sutures are in place (Fig. 3) and then tie all sutures. Repeat the same technique on the near side of the vessel. References
FIG. 3. The sutures on each side are tied after all are placed in position.
(third position). After the needle penetrates the donor artery wall and the tip is grasped by the needle holder, assist the passage of the complete needle with the microfork. As soon as the needle has completely passed through the wall (Fig. 2 d), straddle the suture with the microfork at a point just before it enters the outside wall of the cortical vessel, that is, proximal to the first needle thrust, and move the suture distally until the tip of the microfork can be pressed against the
J. Neurosurg. / Volume51 / September, 1979
1. Acland R: New instruments for microvascular surgery. Br J Surg 59:181-184, 1972 2. Buncke HJ: Personal communication, 1979 3. Donaghy RMP: Personal communication, 1979 4. Jacobson JH II: Personal communication, 1979 5. Yasargil MG: Experimental small vessel surgery in the dog including patch and grafting of cerebral vessels and the formation of functional extracranial-intracranial shunts, in Donaghy RMP, Yasargil MG: Microvascular Surgery. Report of First Conference, October 6-7, 1966, Burlington, Vermont. St Louis: CV Mosby, 1967, pp 87-126 6 Yasargil MG: Mierosurgery Applied to Neurosurgery. New York: Academic Press, 1969, pp 39, 63, 64, 67
Address reprint requests to." Milton D. Heifetz, M.D., Department of Neurological Surgery, University of Southern California, 704 North Bedford Drive, Beverly Hills, California 90210.