Length-boosting surgery for 'micro-penises'

News articles and features | New Scientist

Length-boosting surgery for ‘micro-penises’

19:17 06 December 04
NewScientist.com news service

A new surgical procedure has allowed men with abnormally short penises to enjoy a full sex life and urinate standing up, some for the first time. Tiny "micro-penises" have been enlarged to normal size without losing any erogenous sensation, say UK doctors.

"Micro-penis" refers to any penis shorter than 7 centimetres when fully erect - approximately half of the average length (12.5 cm). Approximately one in every 200 men have a micro-penis, either because of a birth defect or because they have undergone cancer treatments.

"It’s not so much penile enlargement as penile construction," says David Ralph at the University College of London, UK, who will describe the technique on Wednesday at a sexual medicine conference in London. Until now, these men have not been able to have sex or urinate in a urinal because their penis was too short.

In the past, flaps of skin from the forearm had been used to reconstruct a penis from scratch, either to physically transform women into men or to replace an amputated penis. But this technique actually fuses the new penis with the existing one so, besides the adding of sheer bulk, erogenous sensation can be preserved.

Cylindrical flap

Ralph operated on nine men aged between 19 and 43 with a range of medical histories, including three hermaphrodites, two with other birth defects and two whose penises did not develop properly after undergoing chemotherapy as infants.

He made three 12.5 cm incisions in the arms of these patients, harvesting a square flap of skin. While it was still attached to the arm he rolled it up "like a Swiss roll" with a tube running down the centre. Ralph then cut off the cylindrical flap and sewed it at one end to the base of the micro-penis - so that original penis ran along the inside of the cylinder.

To preserve erogenous sensation, he also cut the tip of the penis - called the glans - away from the main shaft, while leaving the blood vessels and nerves intact. While still being connected to the blood vessels and nerves of the micro-penis, the glans was sewn back to the outside end of the new penis. Arteries, veins and nerves from the pelvis were also joined to supply the new penis.

Full sexual function

The skin on the arm is perfect, says Ralph, because the blood vessels are about the same size as those in the pelvis and are positioned so that the two can easily be joined together. The arm is restored with a skin graft from the buttocks.

But for full sexual function, a penile prosthesis - used frequently by men who have problems achieving an erection - must also be implanted. It consists of a silicone cylinder that lines the penis shaft and is attached via a pump to a silicone reservoir in the abdomen. Pushing a button under the scrotum causes fluid to pass from the reservoir into the shaft, stiffening the penis.

"It’s certainly a nice gain for the field," says Anthony Atala, a urologist at Wake Forest School of Urology in Winston-Salem, North Carolina, US. No one had ever combined the disconnection of the glans with a skin graft, he says.

Transsexuals and amputation victims who have skin transferred from their forearm to the pelvis have no glans to start off with, and so have to manage without erogenous sensation in their reconstructed penis. And patients with abnormally short urethras have had their glans disconnected to undergo a urethra extension, but this had not been combined with a skin graft.


Celeste Biever

Also of interest (apologies if already posted):

News articles and features | New Scientist

Tissue engineers grow penis in the lab
19:00 11 September 02

In a remarkable feat of tissue engineering, major parts of the penises of several rabbits have been replaced with segments grown in a lab from their own cells. The animals were able to use the reconstructed organs to mate.

Researchers have grown lengths of the corpus cavernosum in the lab

The next step is to try to recreate the entire organ from scratch. The technique could make it possible to reconstruct the penises of men who have suffered injuries or those of children born with genital abnormalities.

"If you have a child born with ambiguous genitalia, it’s a life-changing event," says Anthony Atala of Harvard Medical School, whose team carried out the work.

It could also provide an alternative to the crude methods currently used to enlarge the organ, such as injecting fat cells or cutting the penis’s suspensory ligament and "pulling out" more of the internal part. Instead, a patient would have penile cells removed by a doctor and, a few weeks later, the organ or parts of it grown using the cells could be surgically implanted.

More complex

While the particular nature of the research is likely to attract much attention, it is also one of the most impressive attempts at tissue and organ engineering to date. "The penis is more complex than any of the organs we have engineered so far," says Atala, whose team has already created fully functional bladders that may soon be implanted in people.

The penis is more difficult to recreate because it has more functions and, unlike the bladder, is also a solid organ.

It consists of three main cylinders, encased in an outer layer of connective tissue, skin, blood vessels and nerves. The two biggest cylinders, made of spongy material that swells during an erection, are the corpora cavernosa. The third tube encases the urethra.

Of those structures, the corpus cavernosum is the most challenging to replace or reconstruct. It contains specialised muscle and endothelial cells - the cells that line blood vessels - and its structure is hard to mimic. Yet this is the part that Atala has been able to grow.

Half pressure

His team first extracted three-dimensional scaffolds of collagen from the erectile tissue of rabbits. They also took samples of the specialised muscle and endothelial cells from penises of each of the rabbits destined to receive the implants.

These cells were grown separately at first, and then added to the collagen matrix in the appropriate proportions. After a few days more growth, the result resembled real erectile tissue.

Next, Atala removed the corpora cavernosa from almost the entire length of the exterior part of the penises of 18 rabbits, leaving the nerves and urethra intact. He then replaced them with the engineered erectile tissues. Because the tissues were grown from the rabbits’ own cells, there was no problem with immune rejection.

Once they had recovered from the surgery, the rabbits attempted to have sex within 30 seconds of being put in a cage with a female. "They were able to copulate, penetrate and produce sperm," Atala told New Scientist.

More detailed studies revealed that the penises generated about half of the normal pressure of an erect penis. "It’s analogous to the penis of a 60-year-old man, versus that of a 30-year-old," says Atala. Details of the work will be published in the October issue of The Journal of Urology.


Sylvia Pagán Westphal, Boston

Damn, Lurky you beat me to it. I luckily checked the main index before posting it.

*I* beat Twatteaser?

Whaddya, gettin’ old or something?

;)

My pleasure.

I am old and just got up.

Pretty soon there will be no more need to PE