Where is the mesorectal located?
the rectum
Mesorectum: The mesentery of the rectum, i.e., mesorectum, is the perirectal fatty lymphovascular tissue extending the length of the rectum[5]. The mesorectum encases the rectum as a thick cushion mainly posteriorly and laterally.
What is Mr T category?
T category is characterized by the depth of tumor penetration into the rectal wall and extramural spread into the mesorectum and adjacent structures.
Where are the mesorectal lymph nodes?
There are few lymph nodes within the mesentery of the lower third of the rectum and relatively few in the right and left lateral portions of the mesorectum. We confirm that the majority of nodes are located in the proximal two-thirds of the posterior rectal mesentery.
What is anterior peritoneal reflection?
The anterior peritoneal reflection separates the intra- and extraperitoneal portions of the rectum and is a well-defined anatomic landmark at laparotomy [1].
What is the clinical importance of Denonvilliers fascia?
The Denonvilliers’ fascia (DVF) plays an important role in rectal surgery because of its anatomic position and its relationship to the surrounding organs. It affects the surgical plane anterior to the rectum in the procedure of total mesorectal excision (TME).
What is the anatomy of the mesorectal fascia?
Visceral mesorectal fascia (long solid arrow) is lying anterior to presacral fascia (short solid arrow). High signal deep relative to presacral fascia (arrowhead) represents fat, and signal void of median sacral vessel (open arrow) lies in retrorectal space.
How is the mesorectum shown on an MRI?
The mesorectum is shown on axial MRIs of the cadaveric sections as a high-signal-intensity (similar to the signal intensity of fat) package surrounding the rectum, containing vessels and lymphatic tissue (Fig. 15A, 15B ). Lymph nodes within the mesorectum are shown as high-signal-intensity ovoid structures.
What type of MRI is used for mesorectal excision surgery?
SUBJECTS AND METHODS. High-spatial-resolution T2-weighted MRI was performed using a 1.5-T system in cadaveric sections and in patients before they underwent total mesorectal excision surgery.
Why is the peritoneum enveloped by the mesorectal fascia?
Note that a variable circumference of the rectum is enveloped by the mesorectal fascia, owing to the fact that the peritoneum reflects off the anterior aspect of the middle and upper thirds of the rectum ( see Figure 1 ). 1. Susan Standring. Gray’s Anatomy. ISBN: 9780702052309