Glans penis
From Wikipedia, the free encyclopedia
| Glans penis | |
|---|---|
 |
|
| 1. Testicles 2. Epididymis 3. Corpus cavernosa 4. Foreskin 5. Frenulum 6. Urethral opening 7. Glans penis 8. Corpus spongiosum 9. Penis 10. Scrotum |
|
| Latin | glans penis |
| Gray's | subject #262 1248 |
| Artery | Urethral artery |
| Dorlands/Elsevier | g_06/12392909 |
The glans penis is the sensitive erectile tip of the penis. It is also commonly referred to as the head of the penis, although this is not the proper medical terminology. It is wholly or partially covered by the foreskin, except when the foreskin is retracted, such as during sexual intercourse or masturbation while the penis is erect, or when the foreskin has been removed by circumcision.
Contents |
[edit] Medical considerations
The meatus (opening) of the urethra is at the tip of the glans penis. In small boys who wear diapers, the meatal area of the glans penis is at risk from meatitis, meatal ulceration, and possibly 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 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]
[edit] 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 foreskin maintains the mucosa in a moist environment.[5] In males who have been circumcised, but have not undergone restoration, the glans is permanently exposed and dry. Contrary to widely-held belief, the glans of the circumcised penis does not develop a thicker keratinization layer.[6] Studies have shown that the glans is equally sensitive in circumcised and uncircumcised males,[7] [8] however, many males who have restored their foreskin disagree with these findings.[citation needed] The observed increase in sensitivity frequently is often attributed to the increase in moistness of the covered glans, although others have proposed the placebo effect.[9][10]
Halata & Munger (1986) report that the density of genital corpuscles is greatest in the corona glandis,[11] while Yang & Bradley (1998) report that their study "showed no areas in the glans to be more densely innervated than others."[12]
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 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".[12]
[edit] Additional images
 Diagram of the arteries of the penis. |
 Penis |
[edit] See also
[edit] References
- ^ Freud, Paul (August 1947). "The ulcerated urethral meatus in male children". The Journal of Pediatrics 31 (2): 131-41. DOI:10.1016/S0022-3476(47)80098-8. Retrieved on 2006-07-07.
- ^ a b Halata, Zdenek, A. Spaethe (1997). "Sensory innervation of the human penis". Advances in experimental medicine and biology (424): 265-6. PMID 9361804. Retrieved on 2006-07-07.
- ^ Birley, H. D., M .M. Walker, G. A. Luzzi, R. Bell, D. Taylor-Robinson, M. Byrne & A. M. Renton (October 1993). "Clinical features and management of recurrent balanitis; association with atopy and genital washing". Genitourinary Medicine 69 (5): 400-3. PMID 8244363.
- ^ Edwards, Sarah (June 1996). "Balanitis and balanoposthitis: a review". Genitourinary Medicine 72 (3): 155-9. PMID 8707315.
- ^ Prakash, Satya, Raghuram Rao, K. Venkatesan & S. Ramakrishnan (July 1982). "Sub-Preputial Wetness--Its Nature". Annals Of National Medical Science (India) 18 (3): 109-112.
- ^ Szabo, Robert, Roger V. Short (June 2000). "How does male circumcision protect against HIV infection?". British Medical Journal 320 (7249): 1592-4. PMID 10845974. Retrieved on 2006-07-07.
- ^ Masters, William H., Virginia E. Johnson (1966). Human Sexual Response. Boston: Little, Brown & Co, 189-91. ISBN 0-316-54987-8. (excerpt accessible here)
- ^ Bleustein, Clifford B., James D. Fogarty, Haftan Eckholdt, Joseph C. Arezzo and Arnold Melman (April 2005). "Effect of neonatal circumcision on penile neurologic sensation". Urology 65 (4): 773-7. DOI:10.1016/j.urology.2004.11.007. PMID 15833526.
- ^ Kirby, R. S. (September 1994). "Views and Reviews: The Joy of Uncircumcising! Restore Your Birthright and Maximize Sexual Pleasure". British Medical Journal 309: 679. Retrieved on 2006-07-07.
- ^ Waskett, James H. (2003-12-11). Circumcision and uncircumcision. Rapid responses to "Views and Reviews: The Joy of Uncircumcising! Restore Your Birthright and Maximize Sexual Pleasure". Bmj.com. Retrieved on 2006-07-07.
- ^ Halata, Zdenek, Bryce L. Munger (April 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.
- ^ a b Yang, C. C., W.E. Bradley (July 1998). "Neuroanatomy of the penile portion of the human dorsal nerve of the penis". British Journal of Urology 82 (1): 109-13. DOI:10.1046/j.1464-410x.1998.00669.x. PMID 9698671.
[edit] External links
- SUNY Labs 42:07-0102 - "The Male Perineum and the Penis: The Corpus Spongiosum and Corpora Cavernosa"
- SUNY Labs 44:06-0101 - "The Male Pelvis: The Urethra"
