Effect of newly developed scissors-attached micro-forceps on the recipient clamp time and occurrence of anastomotic site infarction after bypass surgery for moyamoya disease

Abstract

Introduction: This study aimed to examine the effect of newly developed scissors-attached micro-forceps in superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD).

Materials and methods: Of 179 consecutive STA-MCA anastomoses on 95 hemispheres of 71 MMD patients at the University of Fukui Hospital between 2009 and 2023, 49 anastomoses on 26 hemispheres of 21 patients were enrolled in this retrospective cohort clinical trial intraoperative indocyanine green video-angiography did not demonstrate bypass patency in three anastomoses in two patients who were excluded. Twenty-one anastomosis in 19 hemispheres of 16 patients were performed using the conventional micro-forceps (conventional group, CG), and 25 anastomoses in 22 hemispheres of 19 patients were performed using scissors-attached micro-forceps (scissors group, SG). A small infarction near the anastomotic site detected using postoperative diffusion-weighted imaging was defined as anastomotic site infarction (ASI). Factors affecting the occurrence of ASI were examined by univariate, logistic regression, and receiver operating curve (ROC) analysis.

Results: There were no significant differences in clinical parameters such as age, sex, number of sacrificed branches, number of sacrificed large branches, and number of sutures between the CG and SG. However, the clamp time and occurrence of ASI were significantly lower in the SG than in the CG. Logistic regression analysis revealed that the clamp time was the only significant factor predicting the occurrence of ASI. A receiver operating curve analysis also revealed that the clamp time significantly predicted the occurrence of ASI (area under the curve, 0.875; cutoff value, 33.2 min).

Conclusion: The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

Keywords: STA-MCA anastomosis; anastomotic site; clamp time; ischemia; micro-forceps; moyamoya disease.

Figure 1

Inclusion of the patients in this clinical trial.

Figure 2

(A) Pair of micro-forceps is 135 mm long and consists of three parts: body, head, and tip (Charmant Co., Ltd., Fukui, Japan, www.charmant.co.jp), which are made of Ti15V3Al3Cr3Sn, stainless steel (SUS304), and aged stainless steel (SUS20J-2), respectively. Each part is fixed and connected by screws made of stainless steel (SUS304). (B) The tip is 0.35 mm wide and 0.8 mm long. There is a small pair of scissors which is 0.8 mm from the tip for cutting ligatures. (C) This small-shaped tip design makes it possible to work with 11-0 ligatures and needles smoothly. (D–F) The micro-forceps allow the surgeon suture, tie, and cut a ligature without exchanging instruments, thus reducing the clamp time.

Figure 3

Asymptomatic small infarct lesion at the frontal and or temporal lobes adjacent to the Sylvian fissure detected by postoperative diffusion-weighted imaging (DWI) is defined as an anastomotic site infarction (ASI). Preoperative (A) and postoperative (B) DWI of a patient with temporal ASI (arrow head). Preoperative (C) and postoperative (D) DWI of a patient with frontal and temporal ASIs (arrows). Preoperative (E) and postoperative (F) DWI of a patient with major postoperative infarction at the affected side is distinguished from ASI.

Figure 4

(A) Clamp time of the recipient artery regarding the SG (24.2 ± 6.9 min) was significantly shorter than CG (41.0 ± 11.6 min; p < 0.001). (B) The clamp time per suture in the SG (2.4 ± 0.5 min) was significantly shorter that in the CG (4.2 ± 1.4 min; p < 0.001). (C) Occurrence rates of ASI in the SG (16%) were significantly smaller than that in the CG (67%; p = 0.0312). ^*Indicates statistically significant.

Figure 5

Receiver operating characteristic (ROC) analysis regarding the prediction of occurrence of anastomotic site infarctions (ASIs). (A) The clamp time is a significant predictive factor of the occurrence of ASIs (p = 0.0041; AUC = 0.7346; cutoff value, 33.2 min; sensitivity, 68.8%; specificity, 54.6%). (B) Clamp time per suture was a significant predictive factor of the occurrence of ASIs (p = 0.0047; AUC = 0.7271 cutoff value, 3.6 min; sensitivity, 58.3%; specificity, 57.1%).