The Basis Of Anatomy For Clinical Application Of TME Of Rectal Cancer

Objective To discuss the anatomotic structurerelated to TME for rectal cancer in order to direct clinicaloperations.Methods 22 male adult cadaveric specimen fixed byformalin were anatomotied and studied to observe andmeasure the structures,then record data by camera.Results 1) Mesorectum is about 8~10cm in length,andabout 1.5~2.0cm in thickness,there are adipose tissue,blood vessels , nerves , lymphoid tissueinside.2)Denonvilliers fascia: Denonvilliers fascia issituated between the bottom of bladder,seminal vesicle,deferent duct,prostate and rectum.It arises from perinealaponeurosis and is in continuity with rectovesical pouchon the other side.The height of midline averages 3.7cm inmale specimens. Of 4 in 22 male specimens,the Denonvilliersfascia is observed to have vessel structures passingthrough. 3)Waldeyer ligament : Waldeyer ligament is abundle of fiber band which is formed by the confluence ofvisceral pelvic fascia and presacral fascia in front ofS3~S5.Presacral fascia which is in front of sacrum isformed by the confluence of visceral pelvic fascia andparietal pelvic fascia.Parietal pelvic fascia and S1,S2cohere tightly.Presacral venous plexus is located betweenpresacral fascia and sacrum. 4)Between the visceral pelvicfascia and the presacral fascia,there is retrorectalspace,operations for rectal cancer should be done within thisspace.5)Lateral rectal ligament is located between theinferior 1/3 section of rectum and the pelvic wall whichappears constantly in 22 specimens.Lateral rectal ligamentis divided into outer part and inner part.The outer part ismade up of the visceral nerves issued from pelvic plexus ,theouter part is made up of the nerves issued from the superiorhypogastric plexus and middle rectal artery.6)Middle rectalartery doesn't appear necessarily,12 of 22 specimen have thisstucture(54.65%),the diameters of this artery range from 0.6mmto 2mm,average 1.1mm.There is a latent space under lateralligament which is about 4.0cm~4.5cm in length and 2.0cm~3.0cm inwidth.7)Superior hypogastric plexus: Superior hypogastricplexus is located from the end of abdominal aorta and itsbifurcations to where approximate 2cm below sacralpromontory with irregular shape and net structure, then isdivided into 2 branches,namely,left and right hypogastricnerves within the range 1cm~2cm around sacral promontory.Hypogastric nerves: Hypogastric nerves issue from superiorhypogastric plexus within the range 1cm~2cm around sacralpromontory,the 2 branches include angle of about 60 degree,16 ofthe 22 specimen (72.7%)have apparent nerve stem in the.rest 6 specimen (27.2%),they exist in a form of irregularshape and net structure.Pelvic plexus:Pelvic plexus is likea nerve board with irregular shape and net structure,whichis 3.5cm~4.5cm in length and 2.0cm~3.0cm in width.Pelvic plexushas a branch of about 1cm ,which connects pelvic plexus andrectum includes angle of nearly 90 degree between fibersissued forward from pelvic plexus.Conclusions 1)Mesorectum is different from the notion ofmesentery in traditional anatomy.It is situated behind therectum and contains adipose tissue,blood vessels,nerves,lymphoid tissue inside.2)To avoid the local recurrence afteroperations, the surgeon should make sharp dissections withhis sight on it straightly,when dissecting behind the rectum,so that the mesorectum is kept unbroken.The mesorectum shouldbe excised 5cm below the tumor.3) Prerenal fascia descendsoverjeting the aorta,and forms visceral fascia in front ofsacrum,then heads forward on both sides wrapping pelvic plexus,thisforms the nerve layers.And reentried then wrapped the rectum. 4)Parietal pelvic fascia is strentched down from postrenal fascia andcoheres to visceral pelvic fascia.5)Between the visceral pelvicfascia and the parietal pelvic fascia,there is retrorectalspace,operations for rectal cancer should be done within thisspace.6)Lateral rectal ligament is one strcture that exitsconstantly,composed of the fibers issued from hypogastric nerve,sacral plexus,fibers from sacral sympathetic trunk and middle rectalblood vessels that appear unconstantly.7)Because of the thicknessof the diameter of the middle rectal artery,we don't need toligate ,we can cut the lateral ligament sharply or by electroniccoagulation, this way we can avoid the damage of the fibers issuedfrom pelvic plexus to uropoiesis system and reproductivesystem.8)There is a latent space under the lateral ligament whichconnects retrorectal space and paravesical space.To identify thiscavity is the basic procedure of dealing with the lateral ligamentcorrectly.9)TME puts emphasis on dissecting sharply with straightsight on within the retrorectal space.This way we can not only keepthe mesorectum unbroken but also is an important measure to preservethe pelvic autonomic nerve.10)Because of the thickness of thediameter of the middle rectal artery,we can cut the lateral ligamentby electronic coagulation,this way we can avoid the damage of thefibers issued from pelvic plexus to uropoiesis system andreproductive system...