Prostatic utricle

The prostatic utricle (Latin for "small pouch of the prostate") is a small indentation in the prostatic urethra, at the apex of the urethral crest, on the seminal colliculus (verumontanum), laterally flanked by openings of the ejaculatory ducts. It is also known as the vagina masculina,^[a] uterus masculinus or (in older literature) vesicula prostatica.^[2]

Prostatic utricle
Vesiculae seminales and ampullae of ductus deferentes, seen from the front.
The male urethra laid open on its anterior (upper) surface.
Details
Precursor	Paramesonephric ducts
Identifiers
Latin	utriculus prostaticus, utriculus masculinus, vagina masculina, sinus pocularis
TA98	A09.4.02.009
TA2	3449
FMA	19702
Anatomical terminology [edit on Wikidata]

Structure

It is often described as "blind", meaning that it is a duct that does not lead to any other structures.^[3] It tends to be about one cm in length.^[4] It can sometimes be enlarged.^[5][6] The utricle is deemed enlarged if it allows insertion of a cystoscope at least 2 cm deep.^[7] This is often associated with hypospadias.^[8]

Dissection of prostate showing prostatic utricle opening into the prostatic urethra.

Function

The prostatic utricle is a remnant that is homologous to the female uterus (including the cervix) and vagina, usually described as derived from the paramesonephric ducts,^[9] although this is occasionally disputed.^[10]

In 1905, Robert William Taylor described the function of the utricle: "In coitus it so contracts that it draws upon the openings of the ejaculatory ducts, and thus renders them so patulous that the semen readily passes through."^[11]

See also

• List of related male and female reproductive organs

Notes

1. Especially in cases with intersex men who have female internal organs.^[1]