Design And Experimental Research Of A Retractor In Breast Surgery

Background:Surgery is one of the most important treatments in breast cancer. Surgical scope becomes more and more smaller since Fisher proposed the important theory that "breast cancer is a general disease from beginning" in 1960s. At present, surgical procedure is developing towards the direction of "individualization" and "minimally invasive", the main surgical procedure in breast cancer consist of modified radical mastectomy, breast-conserving surgery and nipple-sparing mastectomy, et al. For the patients with higher aesthetic requirements, BCS is the best choice. However, many patients are not suitable to BCS because their lesions are diffusive or breast glands are small or can't accept radiotherapy,NSM surgery not only conserve nipple-areola complex(NAC), but also remove more than 95% glandular tissue, producing better condition for 1 stage reconstruction or 2 stage reconstruction without radiotherapy after surgery, was appreciate by many patients. So, it could be carried out gradually. But NSM lacks dedicated retractor, and often requires a large incision to remove the whole breast gland. It also influent cosmetic effect. So, designing a dedicated retractor to NSM retractor seems particularly important.Objective:Design and produce a dedicated retractor to NSM surgery, and preliminarily evaluate its safety and practicability in animal experiments and clinical trials.Methods:1?Cooperate with related technical personnel, design and manufacture retractor with independent intellectual property rights in NSM surgery.2?Animal experiment of retractor. Select 10 Bama minipig, and divide them into experimental group and control group, free flap after make a incision in both side of abdomen, simulate the NSM surgery. Original version retractor was used in experimental group and traditional retractor was used in another. Record the surgery time?amount of blooding?WBC and CRP, and do statistical analysis.3?Improve the original version retractor after animal experiment according to the problem found in experiment, and produce the improved version retractor for clinical trial.4?Clinical trial of improved version retractor. Select 12 early breast cancer patients for NSM in PLA general hospital breast disease center, divide them into experimental group and control group randomly. Improved version retractor was used in experimental group while traditional retractor was used in control group to do NSM surgery. Record the surgery time?amount of blooding?WBC?CRP?the length of incision and rate of good cosmetic effect, and do statistical analysis.Results:1?Retractor in NSM surgery was designed and produced successfully, and improved version was manufactured on the basis of animal experiment.2? In animal experiment, the difference on surgery time between experimental group and control group was of statistical significance (t=15.512, P=0.000<0.05), but the difference in amount of blooding?WBC?CRP between experimental group and control group was of no statistical significance (t1=0.116,t2=0.667,t3=0.493,P1=0.9091>0.05,P2=0.5237>0.05, P3=0.6278>0.05)3?Same results were seen in clinical trial, the difference on surgery time between experimental group and control group was of statistical significance (t=2.640, P=0.0334<0.05), but the difference in amount of blooding?WBC?CRP between experimental group and control group was of no statistical significance (t,=0.319,t2=0.513,t3=0.310,P1=0.7581>0.05,P2=0.6217>0.05,P3=0.7641>0.05). The difference in length of incision between experimental group and control group was of statistical significance (t=4.072,P=0.0022<0.05), and both groups on postoperative rate of good cosmetic effect reached 100%.Conclusion:The retractor is of simple structure, and convenient to fix. It is safe and effective in both animal experiment and clinical trial. Improved version retractor can finish NSM with small incision.