Internal urethral orifice

Internal urethral orifice
Urinary bladder
The interior of bladder.
Details
Identifiers
Latin	ostium urethrae internum
TA98	A08.3.01.028F A08.3.01.027M
TA2	3424
FMA	85264
Anatomical terminology [edit on Wikidata]

The internal urethral orifice is the opening of the urinary bladder into the urethra.^[1]

Anatomy

It is usually somewhat crescent-shaped.^{[citation needed]}

Relations

It is formed by the neck of the urinary bladder. It opens at the apex/inferior angle of the trigone of the bladder, some 2-3 cm anteromedial to either ureteral orifice.^[1]

The mucous membrane immediately posterior to it presents a slight elevation in males - the uvula vesicae - caused by the middle lobe of the prostate.^{[citation needed]}

References

This article incorporates text in the public domain from page 1232 of the 20th edition of Gray's Anatomy (1918)

^ ^a ^b "orifice interne de l'urèthre l.m. - Dictionnaire médical de l'Académie de Médecine". www.academie-medecine.fr. Retrieved 2024-06-01.

External links

Anatomy photo:44:06-0106 at the SUNY Downstate Medical Center - "The Male Pelvis: The Urethra"

Male reproductive system

Internal

Seminal tract

Testicles	Layers Tunica vaginalis Tunica albuginea Tunica vasculosa Appendix Mediastinum Lobules Septa Leydig cells Sertoli cells Blood–testis barrier
Spermatogenesis	Spermatogonium Spermatocytogenesis Spermatocyte Spermatidogenesis Spermatid Spermiogenesis Spermatozoon
Other	Seminiferous tubules Tubuli seminiferi recti Retia testes Efferent ducts Epididymides Appendix Inferior ligaments Superior ligaments Stereocilia Paradidymides Spermatic cords Pampiniform plexus Vasa deferentia Ampullae Rectovesical pouch Ejaculatory ducts Testicular arteries Testicular veins

Accessory glands

External

Penis	Root Crura Bulb Fundiform ligament Suspensory ligament Body Corpora cavernosa Trabeculae of corpora cavernosa Corpus spongiosum Trabeculae of corpus spongiosum Glans Foreskin Frenulum Corona Septum glandis Fascia Superficial Deep Tunica albuginea Septum Raphe Arteries Arteries of bulb Dorsal arteries Deep arteries Internal pudendal artery Veins Dorsal veins Vein of bulb Internal pudendal veins Nerves Dorsal nerves Pudendal nerves Urethra Internal urethral sphincter Internal urethral orifice Pre-prostatic Prostatic Intermediate Spongy External sphincter muscle Navicular fossa Lacuna magna External urethral orifice Lacunae of Morgagni Urethral glands
Scrotum	Layers Skin Dartos fascia External spermatic fascia Cremaster Cremasteric fascia Internal spermatic fascia Ligament Raphe Septum Arteries Anterior scrotal arteries Posterior scrotal arteries Nerves Anterior scrotal nerves Posterior scrotal nerves Perineal nerve Posterior scrotal veins

Penis