Research On The Upper Margin Structure Of Tarsal Plate And Clinical Applicaton Of Firm-suspension Technique In Asian Blepharoplasty

1、 Study on the upper marginal structure of tarsal plate.The first part of this paper is about the upper edge structure of tarsal plate.The purpose,methods,results and conclusions of this part of the basic research are as follows:Objective: In the incisional double eyelid surgery,the levator aponeurosis,the levator muscle,the Muller muscle,and the upper part of tarsal plate form a complex and delicate anatomical area,which is collectively referred to as the local structure of the upper edge of tarsal plate.The upper edge structure of tarsal plate plays an important role in the reconstruction of the upper eyelid dynamic system in the incisional double eyelid surgery,but the anatomical structure of this area is still unclear.This article will study the upper edge structure of tarsal plate from the anatomical and histological aspects.In order to reveal the structure of this region more accurately and better guide the clinical application of double eyelid surgery.Methods: The upper eyelid tissue specimens of 10 fresh cadavers(20 sides)were obtained from the Anatomy Laboratory of Xiangya School of Medicine,Central South University.The longitudinal line corresponding to the midpoint of the inner and outer canthus of the upper eyelid is defined as the midline,and the longitudinal lines at the medial and lateral 1/4 distance were defined as the inner and outer lines.The upper region of the tarsal plate was carefully dissected to observe the local structure of the upper edge of tarsal plate.The upper eyelid tissue specimens were longitudinally sectioned at the inner,middle and outer lines,and HE and Masson staining were performed respectively to observe the morphology and distribution of the levator aponeurosis fibers,levator muscle and Muller muscle fibers.The thickness of the meibomian gland tissue on the specimen was defined as the histological thickness of the tarsal upper edge,and the distance between the front and rear fibrous capsules of the tarsal upper edge is defined as the anatomical thickness the tarsal upper edge.The histological thickness and anatomical thickness of the tarsal upper edge were measured on the corresponding specimens of the inner,middle and outer lines.Results:(1)Anatomical study: The average tarsal plate widths of the 20 upper eyelid tissue specimens are as follows: midline9.03±1.52 mm,inner line 8.89±1.63 mm,outer line 8.76±1.72mm;the average thickness of tarsal upper edge is as follows: midline 1.25±0.21 mm,the inner line is 1.26±0.24 mm,and the outer line is 1.19±0.16mm;after removing the skin,orbicularis oculi muscle and conjunctiva from the fresh corpse specimen of the upper eyelid,the levator palpebrae muscle and the levator aponeurosis are distributed in a continuous downward pattern in front of the tarsal plate,Muller muscle is distributed on the edge of the tarsal plate.The thickness of Muller muscle is thinner than that of the tarsal plate.It is like a fascia-like tissue.It is divided into two layers of sarcolemma-like tissue on the edge of the tarsal plate and continues to go down to wrap around the front and back of the tarsal plate.A little adipose tissue is distributed between the levator palpebrae and Muller muscle,separating the two layers of muscle.(2)Histological study: In the upper edge of the tarsal plate,the levator palpebrae muscle and levator aponeurosis run continuously downward in front of the tarsal plate,and the fibers of the levator palpebrae muscle and levator aponeurosis are long and smooth;the Muller muscle connects the upper edge of the tarsal plate,and the muscle fibers are relatively dense and shorter than the levator muscle fibers;there is adipose tissue distributed between the Muller muscle and the levator muscle.The average thickness of the tarsal upper edge was as follows: midline anatomical thickness:0.78±0.15 mm,midline histological thickness: 0.41±0.09mm;inner anatomical thickness: 0.81±0.14 mm,inner histological thickness:0.44±0.12 mm;outer anatomic thickness: 0.76±0.13 mm,outer histological thickness: 0.36±0.08 mm.Conclusion:(1)Anatomical study: the width of the tarsal plate in the Orientals is between 8.0-10.0 mm;the thickness of the upper tarsus in the Orientals is between 1.0-1.5 mm;the upper tarsal plate is the ideal upper eyelid suture Fixed position.(2)Histological study: Muller muscle fibers are denser than levator muscle fibers;the histological thickness of the upper edge of the tarsal plate is about 1/2 of the anatomical thickness;the anatomical thickness of the upper eyelid measured by histological specimens is slightly less than the anatomical study data,the anatomical thickness of the Oriental tarsal plate is between0.6-1.0mm.2、clinical applicaton of firm-suspension technique in Asian blepharoplastyThe second part of this paper is a clinical study based on the structure of the tarsal upper edge.The purpose,methods,results and conclusions of this part of the clinical research are shown as follows:Objective: Based on the study of the structure of the tarsal upper edge,the clinical application effect of the firm-suspension technique in the double eyelid surgery of the Orientals was investigated.Methods: From March 2019 to March 2021,50 cases(100 lateral eyes)of incisional double blepharoplasty were completed using firm-suspension technique.The characteristics of firm-suspension technique in this study are: the levator aponeurosis,the orbital septum stump,and the orbicularis oculi muscle of the incision lower lip are all fixed on the upper edge of the tarsal plate.The patients were followed up after the operation,and the doctors,patients and a third party compared the photos before and more than 6 months after the operation to evaluate the effect of the operation.All three parties are satisfied as significant effectiveness,two parties are satisfied as effective,one party is satisfied as average,and neither party is satisfied as poor.Results: Among 50 patients(100 lateral eyes),42 were significantly effective,6 were effective,2 were moderately effective,0 were poor,and the satisfaction rate was 96%(48/50).Conclusion: The firm-suspension technique could achieve satisfactory postoperative results in the Oriental incision double eyelid surgery,and the double eyelid fold shape is stable.