Urethra Flashcards
What is the urethra?
What tissue is it lined by?
Vessel responsible for transporting urine from the bladder to an external opening in the perineum
Stratified columnar epithelium
Describe the male urethra?
What three parts can the male urethra be split into?
15-20cm long, transports urine and semen-sperm and sex glands secretion.
Prostatic
Membranous
Penile
What is involved in the prostatic urethra?
Begins as a continuation of the bladder neck and passes through the prostate gland.
Receives the ejaculatory ducts (semen and seminal fluid) and the prostatic ducts (alkaline fluid)
It is the widest and most distensible portion of the urethra.
What is involved in the membranous urethra?
Passes through the pelvic floor and the deep perineal pouch
It is surrounded by the external urethral sphincter which provides voluntary control of micturition
It is the narrowest and least distensible portion of the urethra
What is involved in the penile urethra?
Passes through the bulb and corpus spongiosum of the penis, ending at the external urethral orifice (the meatus)
Receives the bulbourethralglands proximally
In the glans of the penis the urethra dilates to form the navicular fossa
How does each portion of the male urethra receive a blood supply?
Prosatic urethra- inferior vesical artery
Membranous urethra- supplied by bulbouethral artery
Penile urethra- supplied directly by branches of the internal pudendal artery
How are nerves supplied to the male urethra?
How does it drain lymphatically?
Prostatic plexus
Prosatic and membranous urethra–> internal iliac nodes
Penile urethra–> deep and superficial inguinal nodes
What are the two angles to consider when completing male cathetirisation
What are the three constrictions of the male urethra?
Prepubic angle- can be eliminated by holding penis upright
Infrapubic angle
Internal urethral sphincter, external urethral sphincter, external urethral orifice
What is the course of the female urethra?
short, 4cm in length. Begins at neck of bladder anf passes inferiorly through perineal membrane and the muscular pelvic floor. Opens into the vstibule an area between the labia minora
The distal end of the urethra is marked by Skene’s glands
What artery supllies the female urethra?
What nerve supplies the female urethra?
What is the lymphatic drainage of the female urethra?
Internal pudendal artery, vaginal arteries and inferior vesical braches of vaginal arteries
Vesical plexus and pedendal nerve, afferents are pelvic splachnic nerves
Proximal- internal iliac nodes
Distal- superficial inguinal nodes
