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Laparoscopic pelvic anatomy is presented from a patient that was undertaken to laproscopic pelvic lymphnode dissection and hysterectomy.
Knowledge of anatomy and being aware of three dimensional relationship of structures helps to orientate.

Paravesical space consists of 2 lateral fossa and one medial paravesical fossa.

Boundries of paravesical space are bladder, pubic ramus, iliopectineal line, external iliac artery and vein and pelvic floor muscles.

Umbilical artery separates the medial paravesical fossa from lateral spaces.

Dissection on the left side is shown. Medial paravesical space is also called Wagner fossa. This is labelled as 3 on the picture. Lateral paravesical space can be divided into obturator fossa, labeled as 2 and lateral paravesical fossa, labeled as 1.

Lateral paravesical spaces are a continuation of Retzius space.

Note on the picture that external iliac artery and vein are written in green color. Ureter is labeled as U. You can see iliopectineal line just below external iliac vein. Obturator nerve is written in yellow color. Umbilical artery is continuation of internal iliac artery and separates> lateral paravesical fossa from medial fossa.

Psoas muscle and genitofemoral nerve just lateral to external iliac vessels can be seen. Circumflex iliac vein crossing over external iliac vein is also seen.

Lateral Paravesical space 1: lateral paravesical fossa.

It lies just lateral to umbilical artery. The line separating lateral paravesical fossa from obturator fossa is obscure.

Dissection of lateral paravesical fossa is shown on the left side.
Dissection plane between external iliac vein and umbilical artery can be found easily.
Obturator nerve is seen under the external iliac vein and dissection plane is carried more medially to nerve.
This plane is relatively avascular and can be developed by blunt dissection.
Pelvic floor muscles are seen.
Obturator nerve is seen on the lateral border.
This paravesical space lies just lateral to umbilical artery.

Notice relation of internal iliac,external iliac artery and external iliac vein to paravesical space 1

Paravesical space 3 lies just medial to umbilical artery.
It is bounded by umbilical artery, ureter, uterine artery, vesical pillars and bladder.

Medial paravesical space can be developed between umbilical artery and uterine artery.
Opening of this fossa helps to isolate uterine artery.
Surgeon can encounter superior vesical artery in this space.


Paravesical space 2 is the most lateral paravesical space. It is also named as obturator fossa. It is bounded anteriorly by obturator membrane, iliopectienal line, superiorly by external iliac vein, medially by obturator nerve and lymphatics within the proximity. Posteriorly the space is limited by the bifurcation point of external iliac artery and internal iliac artery, as well as internal iliac vein. Obturator internus muscle and piriformis muscle delineates the obturator fossa.
Important structures that can be encountered in the obturator fossa are; obturator nerve, obturator artery and vein, corona mortis, branches of internal iliac vein and lumbosacral nerve truncus.


Lateral or medial approach to this space can be used for different surgical practices.
The space can be approached medially beneath medial side of external iliac vein. During dissection, corona mortis can be encountered anywhere. Corona mortis is an anastomotic branch between external iliac vein and obturator vein.
Although it can be encountered anywhere on the course of external iliac vein, it is mostly located at the distal part of external iliac vein where it courses above pubic ramus to reach under the inguinal ligament. This branch courses on the bone as it exits from external iliac vein, and typically travles to the medial side of the nerve to reach obturator vein that is located under the nerve.

Lateral approach to obturator fossa allows to visualize entrance of obturator nerve to pelvis. Many branches from internal iliac vein courses transversely below the nerve at this point. Lumbosacral nerve trunk lies below the obturator nerve and these vessels.

The branches of internal iliac vein should be handled kindly.

Obturator arteries are shown on the right side of pelvis.

Now right obturator nerve is shown. Obturator nerve originates from anterior branches from L2, L3 and a branch from L4.

Obturator nerve descends initially between fibers of psoas muscle and the enters the pelvis. After it courses in the obturator fossa, it leaves pelvis by passing through obturator foramen.
It innervates adductor muscles; adductor longus, adductor brevis, gracilis, obturator internus, and a part of adductor magnus.
It is also responsible for the sensory innervation of the skin of the medial aspect of the thigh.

Pararectal space can be entered between ureter and broad liagament on the medial side and internal iliac artery on the lateral side. The space is bounded by hollow curve of sacrum posteriorly. Levator muscles, coccygeal muscles can be reached caudally. The space is limited by uterine artery and parametrium anteriorly.
Middle rectal artery and pelvic splanchnic nerves nerves can be identified in this space.

Middle rectal artery in this fossa indicates that dissection is taken on the middle upper part of rectum.

This fossa is delineated by uterine artery, vein and parametrium anteriorly.

Splanchnic nerves nerve roots from S1,S2, S3 and S4, middle rectal artery and uterine vein is shown.

The pelvic splanchnic nerves are are important for bladder and rectal function.
As shown from a nerve sparing radical hysterectomy operation, these nerves create a complex network in the pelvis. However, it is possible to delineate the structures by following principals.

In the pararectal fossa hypogastric nerve pleksus can also be identified easily by a medial approach to to the ureter which is named Okabayashi, or lateral to the ureter in pararectal fossa.
Hypogastric nerve lies 2-3 centimeter below the ureter.
Hypogastric nerve continues inferiorly on the left and right side of the body, where it descends into the pelvis to form the inferior hypogastric plexus. They carry sympathetic branches to the hypogastric pleksus. These sympathetic nerves supply bladder neck and smooth muscle of internal sphincter of anal canal.
Our dissection planes yield pelvic nerves slightly different from Doctor Shingo Fujiis drawings of nerve sparing radical hysterectomy.

Rectovaginal space can be entered in the midline between uterus and rectum or it can approached from lateral side safely after mobilizing ureter. As the surgeon enters this space, he should recognize the yellow tissue of mesorectum.


Uterine Artery is demonstrated on the right side.
It is a branch of internal iliac artery and it always crosses over the ureter. Hence it is said; water under the bridge.

Accessory vesical vessels can originate from uterine artery in some of the cases.
It is important to be able to dissect and isolate uterine artery. A recent randomized trial showed that it can be advantageous to occlude uterine artery at its origin on the internal iliac artery during laparoscopic hysterectomy.