Jump to content

Glans penis

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by 89.226.117.72 (talk) at 17:55, 21 July 2011 (Undid revision 440689476 by NHRHS2010 (talk) npov, inappropriate term.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Glans penis
Anterior view of the glans penis of an intact penis
Details
ArteryUrethral artery
Identifiers
LatinGraySubject = 262
TA98A09.4.01.007
TA23668
FMA18247
Anatomical terminology

The glans penis (or simply glans) is the sensitive bulbous structure at the distal end of the penis. The glans penis is anatomically homologous to the clitoral glans of the female. When the penis is flaccid it is sometimes fully or partially covered by the foreskin, except in men who have been fully circumcised.

The glans is also commonly referred to as the "head of the penis", while common British slang terms include "helmet," "knob end" and "bell end", all referring to its distinctive shape. The medical name comes from Latin glans "acorn" + penis "of the penis" – the Latin genitive of this word has the same form as the nominative.

Medical considerations

The meatus (opening) of the urethra is at the tip of the glans penis. In circumcised infants, the foreskin no longer protects the meatal area of the glans; consequently, when wearing diapers, there may be greater risk of developing meatitis, meatal ulceration, and meatal stenosis.[1]

The epithelium of the glans penis is mucocutaneous tissue.[2] Birley et al. report that excessive washing with soap may dry the mucous membrane that covers the glans penis and cause non-specific dermatitis.[3]

Inflammation of the glans penis is known as balanitis. It occurs in 3–11% of males, and up to 35% of diabetic males. It is more common among intact males.[4] It has many causes, including irritation, or infection with a wide variety of pathogens. Careful identification of the cause with the aid of patient history, physical examination, swabs and cultures, and biopsy are essential in order to determine the proper treatment.[4]

Anatomical details

The glans penis is the expanded cap of the corpus spongiosum. It is moulded on the rounded ends of the Corpora cavernosa penis, extending farther on their upper than on their lower surfaces. At the summit of the glans is the slit-like vertical external urethral orifice. The circumference of the base of the glans forms a rounded projecting border, the corona glandis, overhanging a deep retroglandular sulcus (the coronal sulcus), behind which is the neck of the penis. The proportional size of the glans penis can vary greatly. On some penises it is much wider in circumference than the shaft, giving the penis a mushroom-like appearance, and on others it is narrower and more akin to a probe in shape. It has been suggested that the unique and unusual shape of the glans in humans has evolved to serve the function of "scooping" any remnant semen deposited by other rival males out of the deeper part of the vagina of a female who may have recently copulated, and thereby decreasing the chance of the rival male from impregnating the female.[5] Other theorists[who?] suggest that its distinctive shape evolved to heighten the sexual pleasure experienced by the female during vaginal intercourse. In this theory, the glans increases friction and tension at the mouth of the vagina by its additional girth and the dilating properties of its probe-like shape.

The foreskin maintains the mucosa in a moist environment.[6] In males who have been circumcised, the glans is permanently exposed and dry. Szabo and Short found that the glans of the circumcised penis does not develop a thicker keratinization layer.[7] Several studies have suggested that the glans is equally sensitive in circumcised and intact males,[8][9][10][11] while others have reported that it is more sensitive in intact males[12][13] (the interpretation of one of these studies is disputed[14]).

Halata & Munger (1986) report that the density of genital corpuscles is greatest in the corona glandis,[15] while Yang & Bradley (1998) report that their study "showed no areas in the glans to be more densely innervated than others."[13]

Halata & Spathe (1997) reported that "the glans penis contains a predominance of free nerve endings, numerous genital end bulbs and rarely Pacinian and Ruffinian corpuscles. Merkel nerve endings and Meissner's corpuscles are not present."[2]

Yang & Bradley argue that "The distinct pattern of innervation of the glans emphasizes the role of the glans as a sensory structure".[13]

See also

References

  1. ^ Freud, Paul (1947). "The ulcerated urethral meatus in male children". The Journal of Pediatrics. 31 (2): 131–41. doi:10.1016/S0022-3476(47)80098-8. PMID 20256409. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |month= ignored (help)
  2. ^ a b Halata, Zdenek (1997). "Sensory innervation of the human penis". Advances in experimental medicine and biology. 424: 265–6. PMID 9361804. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  3. ^ Birley, H. D. (1993). "Clinical features and management of recurrent balanitis; association with atopy and genital washing". Genitourinary Medicine. 69 (5): 400–3. PMC 1195128. PMID 8244363. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help); line feed character in |coauthors= at position 66 (help)
  4. ^ a b Edwards, Sarah (1996). "Balanitis and balanoposthitis: a review". Genitourinary Medicine. 72 (3): 155–9. PMC 1195642. PMID 8707315. {{cite journal}}: Unknown parameter |month= ignored (help)
  5. ^ Gallup, Gordon (2003). "The human penis as a semen displacement device". Evolution and Human Behavior. 24 (4): 277–289. doi:10.1016/S1090-5138(03)00016-3. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  6. ^ Prakash, Satya (1982). "Sub-Preputial Wetness--Its Nature". Annals of National Medical Science (India). 18 (3): 109–112. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  7. ^ Szabo, Robert (2000). "How does male circumcision protect against HIV infection?". British Medical Journal. 320 (7249): 1592–4. doi:10.1136/bmj.320.7249.1592. PMC 1127372. PMID 10845974. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  8. ^ Masters, William H. (1966). Human Sexual Response. Boston: Little, Brown & Co. pp. 189–91. ISBN 0-316-54987-8. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) (excerpt accessible here)
  9. ^ Bleustein, Clifford B. (2005). "Effect of neonatal circumcision on penile neurologic sensation". Urology. 65 (4): 773–7. doi:10.1016/j.urology.2004.11.007. PMID 15833526. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  10. ^ Bleustein, Clifford B. (April 26-May 1, 2003). "Effects of Circumcision on Male Penile Sensitivity". American Urological Association 98th Annual Meeting. Chicago, Illinois. {{cite conference}}: Check date values in: |date= (help); Unknown parameter |booktitle= ignored (|book-title= suggested) (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
  11. ^ Payne, Kimberley (2007). "Sensation and Sexual Arousal in Circumcised and Uncircumcised Men". Journal of sexual medicine. 4 (3): 667–674. doi:10.1111/j.1743-6109.2007.00471.x. PMID 17419812. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  12. ^ Sorrells (2007). "Fine-touch pressure thresholds in the adult penis". British Journal of Urology International. 99 (4): 864–869. {{cite journal}}: Unknown parameter |month= ignored (help)
  13. ^ a b c Yang, DM (2008). "Circumcision affects glans penis vibration perception threshold". Zhonghua Nan Ke Xue. 14 (4): 328–330. PMID 18481425. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help) Cite error: The named reference "yang" was defined multiple times with different content (see the help page).
  14. ^ Waskett, Jake H. (2007). "Fine touch pressure thresholds in the adult penis". BJU International. 99 (6): 1551–1552. doi:10.1111/j.1464-410X.2007.06970_6.x. PMID 17537227. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  15. ^ Halata, Zdenek (1986). "The neuroanatomical basis for the protopathic sensibility of the human glans penis". Brain Research. 371 (2): 205–30. doi:10.1016/0006-8993(86)90357-4. PMID 3697758. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Glans_penis&oldid=440689990"