開存率を高めるためのテクニカルポイント

抄録

There are two kinds of microvascular anastomosis; end-to-end and end-to-side, but no essential differences in these two.
If the diameters of the two vessels are too different in size to make end-to-end anastomosis, end-to-side anastomosis can be chosen.
As an example, a case of the superficial temporal artery (STA) cortical branch of the middle cerebral artery (MCA) anastomosis is described to explain the technical points of the procedure of end to side anastomosis. (The diameter of the vessels: 1-1.5 mm)
The STA as a donor vessel should be dissected free from the subcutaneous tissue leaving some perivascular soft tissue around it, not to injure the vasovasorum of the STA. However the tip of the STA ca. 3 mm in length, where anastomosis is performed, should be completely free from the perivascular soft tissue. If this soft tissue is left around the tip of the STA and caught into the anastomosis cavity, the process of thrombosis occures there.
This dissection of the STA should be done under an operating microscope.
Temporary clips must have low pressure.
To make the anastomosis cavity larger, the STA should be cut obliquely and longitudinally in addition. (A<b) The edges of the cut-end are better left. (Fig. 1)
The lumen of the vessel is washed with heparinized saline.
As a recipient vessel, the cortical branch of the MCA is prepared after cutting the arachnoid membrane. A rubber dam is laid under the recipient vessel in order not to njure the cortical surface of brain during the procedure of suturing.
A 10-0 monofilament nylon is used for sutures.
A microforceps (Inox No.5) in the left hand is inserted into the vessel and opened gently and through a space between the two tips of the forceps, a needle is sticked into the vessel wall (Fig. 2) A microforceps (Inox No.1) is used as a needle-holder in the right hand.
The intima of the vessels may not be picked with forceps. If so, thrombosis will occur at the site.
During the operation the vessels should always be kept wet.
Intraoperatively, and for 1 week postoperatively low molecular dextran, 500 ml per day, is used as an antiplatelet drug. Systemic use of Heparin is not necessary.
Blood transfusion is not recommended till Hb is under 9g/dl, to keep the potentiality of patency higher.