Study on the Impact of Single-port Laparoscopic Surgery Based on Minimally Invasive Instrument Engineering Optimization on Biomarkers of Ovarian Reserve Function

WU Wen-yan; CHEN Fu-chun; ZHANG Ling-jie; WANG Jin-yong; LIN Shu-ping

Abstract：Objective: To investigate the quantitative influence of engineering parameters (diameter, bending angle) of minimally invasive surgical instruments and single-port laparoscopic surgery on biomarkers of ovarian reserve function, and establish a multi-parameter coupled mathematical prediction model, providing a theoretical basis for precision instrument design and operation optimization. Methods: A total of 45 reproductive-age patients undergoing single-port laparoscopic ovarian cystectomy were selected. Through orthogonal experimental design, the instrument diameter (3/5/8 mm) and bending angle (30°/60°/90°) were divided into 9 groups, with 5 cases in each group. Changes in serum AMH (anti-Müllerian hormone), FSH (follicle-stimulating hormone), INHB (inhibin B) and ultrasonic AFC (antral follicle count) indexes were measured before surgery and on the 2nd to 3rd day of the first menstrual period after surgery. Enhanced CT images and laparoscopic images of ovarian force distribution were obtained. Finite element analysis (FEA) of the single-port instrument-ovarian tissue model was performed using ABAQUS software to calculate stress distribution in the ovarian cortex. Oscillatory shear experiments were used to determine the characteristics of viscoelastic property changes in the linear viscoelastic range of ovarian tissue. Results: The rate of decrease in AMH was lower in the 3 mm diameter-30° angle group (P<0.05); the peak Von Mises stress in the D3-θ30 group was lower than that in the other groups (P<0.05); the optimal parameter combination was a diameter of 3.13 mm and an angle of 21.72°, with the model calculating an AMH attenuation of 20%. Ovarian tissue changed with the frequency of the oscillatory shear test. In the low-frequency region (<1 Hz): G'>G'' (elasticity-dominated); in the high-frequency region (>5 Hz): G''>G' (viscosity-dominated); the crossover point was at 5 Hz, where G'=G''=5 kPa. Before ovarian dissection: G' was relatively high and G'' was relatively low, with elasticity dominating. During dissection: G' decreased and G'' increased, with instrument stress causing damage. After dissection: G' further decreased and G'' continued to rise, resulting in irreversible damage to the ovarian stroma. Conclusion: The engineering parameters of minimally invasive instruments significantly affect the ovarian reserve function index AMH and the peak Von Mises stress of the ovary through mechanical stress transmission. Using an instrument with a diameter of 3.13 mm and a bending angle of 21.72° can more effectively reduce the impact of single-port laparoscopic surgery on AMH decline.