Three-dimensional Visualization Of Blood Supply Of The Upper Labial Muscles Using MICRO-CT And Implications For Plastic Surgery

Background:There are fine and complex anatomical structures in upper labial muscles.Biomimetic repair of the muscles plays an important role in upper lip morphology correction.The study of the blood supply of upper labial muscles and vascular protection strategy during nasolabial muscle reconstruction is important to the functional recovery after muscle tension reconstruction.Few researchers have paid attention to upper labial muscle microvasculature,for existing methods limiting simultaneous three dimensional visualization of the microvasculature and muscles.The anatomy of arterial branches in the upper lip and their relationship with soft tissue are not well described in the literature.Objective:The purpose of this study was to explore a three-dimensional visualization method of the micro vessels and soft tissue and to gain a better understanding of the upper lip blood supply.Moreover,this study was to explore the blood supply of upper labial muscles and determine the methods of vascular protection during muscle degloving and dissectionMethods:Lead oxide-gelatin injections and iodine staining were performed in 17 stillborn fetuses.Thirty-four half upper lip specimens were obtained and scanned using micro-computed tomography.The images were then observed and three-dimensional reconstructions were performed using Inveon analysis software.Results:The superior labial artery and inferior alar artery mainly supplied the upper lip.Sometimes,the infraorbital artery and the lateral nasal artery also branched off to the upper lip.The anatomical variations were classified into six types,based on the observed patterns of vascular composition.The skin was supplied by the subcutaneous vascular network,formed by the superficial ascending branches of the superior labial artery and inferior alar artery.The mucosa was supplied by the submucosal vascular network,formed by the deep ascending branches of the superior labial artery and the labial branches of the infraorbital artery.The muscles were supplied by small vertical branches from the subcutaneous and submucosal vascular networksThe superior labial artery was located in the deep layer of the AEB and vermilion area.The muscle in the AEB area was supplied by vertical vessels from the submucosal vascular network.The inferior alar artery was located in the superficial ECD area.The muscle in the ECD area was mainly supplied by vertical vessels from the subcutaneous vascular networkConclusion:The vasculature of the nasolabial muscle can be divided into zones,which are associated with the distribution of muscle fibers.Protecting the vasculature of the upper labial muscle as far as possible and realizing the biomechanical bionics of the muscles is essential in upper lip deformity repair.This study provides new anatomical insight into the upper lip by describing the micro vessels and the relationship between the arteries and the soft tissue involved.This is important information for clinical applications in the field of upper lip plastic surgery.