Tunica albuginea (penis)

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Tunica albuginea (penis)
Penis cross section.svg
The penis in transverse section with tunica albuginea shown
Tunica Albuginea.jpg
Transverse section of the penis
Details
Identifiers
Latin tunica albuginea corporum cavernosorum, tunica albuginea corporis spongiosi
TA98 A09.4.01.017
A09.4.01.018
TA2 3593
FMA 19630
Anatomical terminology

The tunica albuginea is the fibrous envelope that extends the length of the corpora cavernosa penis and corpus spongiosum penis. It is a bi-layered structure that includes an outer longitudinal layer and an inner circular layer. [1]

Contents

Structure

Microstructure

The trabeculae of the tunica albuginea are more delicate, nearly uniform in size, and the meshes between them smaller than in the corpora cavernosa penis: their long diameters, for the most part, corresponding with that of the penis.[ citation needed ]

The external envelope or outer coat of the corpus spongiosum is formed partly of unstriped muscular fibers, and a layer of the same tissue immediately surrounds the canal of the urethra.[ citation needed ]

It consists of approximately 5% elastin, with the remainder mostly consisting of collagen. [2]

Function

The tunica albuginea is directly involved in maintaining an erection; that is due to Buck's fascia constricting the erection veins of the penis, preventing blood from leaving and thus sustaining the erect state.[ clarification needed ][ citation needed ]

Additional images

Related Research Articles

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<span class="mw-page-title-main">Bulb of vestibule</span> One of two elongated masses of erectile tissue in the human clitoris

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<span class="mw-page-title-main">Corpus cavernosum penis</span> Sponge-like region of erectile tissue

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<span class="mw-page-title-main">Superficial perineal pouch</span>

The superficial perineal pouch is a compartment of the perineum.

<span class="mw-page-title-main">Dorsal veins of the penis</span>

In human male anatomy, the dorsal veins of the penis are blood vessels that drain the shaft, the skin and the glans of the human penis. They are typically located in the midline on the dorsal aspect of the penis and they comprise the superficial dorsal veinof the penis, that lies in the subcutaneous tissue of the shaft, and the deep dorsal veinof the penis, that lies beneath the deep fascia.

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The fibrous envelope of the corpus cavernosum urethrae is thinner, whiter in color, and more elastic than that of the corpora cavernosa penis. It is called the trabeculae of corpus spongiosum of penis.

<span class="mw-page-title-main">Trabeculae of corpora cavernosa of penis</span>

From the internal surface of the fibrous envelope of the corpora cavernosa penis, as well as from the sides of the septum, numerous bands or cords are given off, which cross the interior of these corpora cavernosa in all directions, subdividing them into a number of separate compartments, and giving the entire structure a spongy appearance.

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Buck's fascia is a layer of deep fascia covering the three erectile bodies of the penis.

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<span class="mw-page-title-main">Body of penis</span> Part of the penis located outside of the pelvic cavity

The body or shaft of the penis is the free portion of the human penis that is located outside of the pelvic cavity. It is the continuation of the internal root, which is embedded in the pelvis and extends to the glans. It is made up of the two corpora cavernosa and the corpus spongiosum on the underside. The corpora cavernosa are intimately bound to one another with a dorsally fenestrated septum, which becomes a complete one before the penile crura. The body of the penis is homologous to the female clitoral body.

<span class="mw-page-title-main">Root of penis</span> Internal portion of the human penis

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<span class="mw-page-title-main">Septum of the penis</span>

In human male anatomy, the septum of the penis or penile septum refers to the fibrous junction (septum) between the two corpora cavernosa of the human penis. The tunica albuginea of the penis forms a thick fibrous coat to the spongy tissue of the corpora cavernosa and corpus spongiosum. The two corpora cavernosa are surrounded by a strong fibrous envelope consisting of superficial and deep fibers. The superficial or outer fibers are longitudinal in direction, and form a single tube which encloses both corpora; the deep or inner fibers are arranged circularly around each corpus and meet in the center. By their junction in the median plane, the inner fibers form the intercavernous septum of the penis.

<span class="mw-page-title-main">Erection</span> Physiological phenomenon involving the hardening and enlargement of the penis

An erection is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, and endocrine factors, and is often associated with sexual arousal, sexual attraction or libido, although erections can also be spontaneous. The shape, angle, and direction of an erection vary considerably between humans.

<span class="mw-page-title-main">Clitoral erection</span> Physiological phenomenon involving the engorgement of the clitoris

Clitoral erection is a physiological phenomenon where the clitoris becomes enlarged and firm.

In biology, a tunica is a layer, coat, sheath, or similar covering. The word came to English from the Neo-Latin of science and medicine. Its literal sense is about the same as that of the word tunic, with which it is cognate. In biology, one of its senses used to be the taxonomic name of a genus of plants, but the nomenclature has been revised and those plants are now included in the genus Petrorhagia.

Penile ulltrasonography is medical ultrasonography of the penis. Ultrasound is an excellent method for the study of the penis, such as indicated in trauma, priapism, erectile dysfunction or suspected Peyronie's disease.

References

PD-icon.svgThis article incorporates text in the public domain from page 1250 of the 20th edition of Gray's Anatomy (1918)

  1. "Penis Anatomy: Gross Anatomy, Vasculature, Lymphatics and Nerve Supply". 2019-07-01.{{cite journal}}: Cite journal requires |journal= (help)
  2. "Male Genital Anatomy » Sexual Medicine » BUMC".