General Specimen Orientation Tips

• Prostate- The prostate sits in the retroperitoneal cavity and encircles the neck of the bladder/urethra. The posterior surface is flat in comparison to the anterior surface. In most DaVinci prostatectomies, the anterior aspect will be heavily studded with staples. The vas deferens and seminal vesicles are attached to the posterior aspect of the base. The apex (distal aspect) comes to a narrow point; whereas the base (proximal aspect) is wide and contains significant cauterization.

 

• Bladder- The most common landmarks for bladder orientation are the ureters. Each ureter sits on the posterior/lateral aspect. The superior/posterior aspect is triangular in appearance and is covered by smooth peritoneum. The inferior aspect contains the urethra.

 

• Kidney- The most common problem for these specimens is distinguishing between superior and inferior poles. Remember, the ureter always points to the inferior pole! The renal vein (wider in diameter and thin walls) sits anterior to the ureter. The renal artery (narrow in diameter and thick/muscular walls) sits superior to renal vein and ureter.

 

• Uterus- First, use the peritoneal reflection as your guide: anterior serosal surface is higher and blunter (from bladder dissection) and posterior serosal surface is lower and comes to a point. Second, use the attached adnexa (in order of anterior to posterior): round ligament, fallopian tube, ovary and ovarian ligament. If no adnexa or cervix are present, then orientation is not always possible- state “unorientated uterus”.

 

• Colon- Orientation from proximal to distal: Cecum- blind pouch which contains appendix, largest diameter within colon. Ascending- contains terminal ileum, distal aspect has attached mesenteric adipose tissue. Hepatic Flexure- between ascending and transverse. Transverse- only segment of colon which contains omentum. Splenic Flexure- between transverse and descending. Descending- runs retroperitoneal, partially covered by peritoneum on anterior aspect. Sigmoid- lies with in pelvis and is fully covered by mesenteric adipose (sigmoid mesocolon). Rectum- covered by adventitia (not serosa), smooth longitudinal muscular layer, and no attached mesenteric adipose. Anus- contains dentate line (transition zone from colonic to anal mucosa), contains anal sphincter muscles.

 

• Lung- Left lung has 2 lobes and middle portion is called lingual. Right lung has 3 lobes. Note: right bronchus is more vertical and runs semi-parallel with trachea.

 

• Thyroid- The thyroid contains two lobes (right and left), which are connected by the isthmus. In some instances the isthmus will have a pointed pyramidal lobe which faces the superior aspect. When the pyramidal lobe is present, the thyroid will take on a W shape. The anterior capsule is smooth and convex, while the posterior capsule is flat and usually cauterized.