MRCS Part B (OSCE) - Online Resources

"

• One peritoneal fold is located in the midline :    Median umbilical fold.
• Two are found laterally on each side :              Medial and lateral umbilical                                                                             folds.

"

"The median umbilical fold is a ridge of peritoneum covering the median umbilical ligament, which is the remnant of the urachus (joined the bladder to the umbilicus in foetal life). "

"The medial umbilical folds are peritoneal coverings over the medial umbilical ligaments, which are the remnants of the occluded foetal umbilical arteries. "

"The inferior epigastric vessels lie in the lateral umbilical folds on each side. "

"An intraperitoneal organ is one that is almost entirely covered with visceral peritoneum. "

"

The intraperitoneal organs are the:

• Stomach, first and fourth parts of the of duodenum.
• Duodeno-jejunal flexure, jejunum, ileum.
• Liver, spleen and tail of the pancreas.
• Transverse colon, sigmoid colon and upper 1/3^rd of the rectum.

"

"

• Primarily retroperitoneal organs develop embryologically in the retroperitoneum and remain there.
• Secondarily retroperitoneal organs develop originally on a mesentery, which then fuses with the peritoneum, leaving a covering of peritoneum only over the anterior surface of the organ.

"

"The kidneys are primarily retroperitoneal. "

"

• 2^nd and 3^rd parts of the duodenum.
• Adrenal glands.
• Pancreas (except the tail).
• Ascending and descending colon, middle 1/3^rd of the rectum.

"

"

The infraperitoneal/subperitoneal organs  are the:

 

• Lower 1/3^rd of the rectum
• Distal ureter
• Urinary bladder

"

The testes develop in the superior posterior abdominal wall, extraperitoneally, from where they descend to the region of the inguinal canal later in foetaldevelopment, before finally reaching the scrotum around the time of birth.
Therefore, this is the path along which an undescended testicle may lie.
Undescended testes commonly lie at the level of the superficial ring/inguinal canal.

Cryptorchidism is the absence of one or more testes from the scrotum.
Note: A retractile testis is one that can be brought into the scrotum with manipulation, but retracts from the scrotum spontaneously or with gentle pressure.

"

Causes of cryptorchidism include:

• Agenesis
• Intra-abdominal arrest
• Incomplete descent
• Ectopic descent

"

"Orchidopexy is a procedure to bring and fix an undescended testes into the scrotum. An orchidectomy is a procedure in which one or both testicles are surgically removed. "

"The main indications for orchidopexy are for treatment of testicular torsion (usually during adolescence) and for cryptorchidism (usually in children). Orchidopexy is performed to reduce the risks of infertility, testicular malignancy, traumatic injury to the testes, development of an inguinal hernia, testicular torsion in adolescents and to maintain the appearance of a normal scrotum. "

"A varicocoele is a dilatation of the pampiniform plexus of veins. "

"The left testicular vein drains into the left renal vein. The right testicular vein drains into the inferior vena cava. As a consequence of this, left side varicocoeles are more common. "

"A hydrocoele is a fluid collection between the parietal and visceral layers of the tunica vaginalis-the double layer of peritoneum which invests the testes. Hydrocoeles can be classified as primary (idiopathic) or secondary. "

"The differential diagnosis of scrotal swellings include epididymal cyst, sebaceous cyst, testicular malignancy, epididymo-orchitis, inguinal hernia, hydrocoele and varicocoele. "