Estrogen and cornea...

[Vincent]

Dear friends,

Did you read that ?

http://www.keratocone.eu/estrogen.pdf

Amitiés
Vincent

Abstract:

Estrogen-induced changes in biomechanics of the cornea as possible reason for keratectasia. (E. Spoerl, F. Raiskup-Wolf, V. Zubaty Department of Ophthalmology Carl Gustav Carus University Hospital Dresden).

AIM: The risk of regression after PRK and the tendency to develop keratectasia after LASIK procedure is higher in women. Currently interest is focused on the influence of estrogen on corneal stability after corneal refractive surgery. The aim of this experimental study was to investigate the change in biomechanical properties of the cornea induced by estrogen
METHODS: The influence of estrogen was investigated in 12 fresh porcine corneas incubated in culture medium with 10microM of beta-estradiol for 7 days. A group of 12 porcine corneas incubated in culture medium without estradiol for the same time served as a control group. Strips of cornea were cut and the stress-strain was measured in a biomaterial tester. The Young's modulus was calculated.
RESULTS: During incubation the thickness of the cornea changed in the control group by only 6.4% and in the estradiol group by 12%. However, the difference in the biomechanical stress values at 10% strain was significantly larger. In the control group was the stress value measured 120.18 +/- 28.93 kPa and in the estradiol group 76.87 +/- 34.63 kPa (p=0.002), representing a reduction of the corneal stiffness by 36% due to the estradiol treatment.
CONCLUSION: Estrogen is a modulating factor of the biomechanical properties of the cornea which is not explainable only by an increased swelling. The significance of the hormone status of patients and its influence on the biomechanical stability of the cornea, a determining factor after refractive surgery, have been underestimated and may contribute to the development of keratectasia.


And:


• Corneal thickness changes during pregnancy (Weinreb,1988)
• Women have 13.5 times higher risk of regression after PRK, if they take oral contraceptives (Corbett,1996)
• After lasik women with HRT show a higher risk for refractive regression (O‘Doherty, 2006)
• Women have 9 times higher risk to develop a keratectasia after lasik (Randelman, 2003)
• Keratoconus starts after puberty.
• Estrogen have been reported to produce keratoconus (steepening of corneal curvature) and intolerance to contact lenses.

• Pharmacology: Cyproterone Acetate--Ethinyl Estradiol. Diane-35 is a combination antiandrogen-estrogen
for use in the treatment of androgen-dependent dermatological conditions in females.

• Indications: For the treatment of women with severe acne, unresponsive to oral antibiotic and other available treatments, with associated symptoms of androgenization, including seborrhea and mild hirsutism.

• Precautions: Ocular Disease: Progressive astigmatic error, possibly leading to keratoconus, has been noted in some myopic women receiving drugs of the estrogen/progestogen class. In women who developed myopia at or near puberty, and in whom myopia stabilized in adult life, estrogen/progestogen combinations after some 6 months of use have increased the refractive error 2- to 3-fold. Women with a family history of myopic astigmatism or keratoconus who are using such therapy may experience rapid advancement of the ocular disorder.
http://www.cbc.ca/consumers/market/file ... update.pdf

[Pat A]

Vincent (and others....._)
I tried to ...but it crashed my computer! I have tried it twice now with the same result....

[Vincent]

Hi pat,

Ooops... The pdf is OK... I don't understand the problem and I am sorry for your computer

[Pat A]

Hi Vincent
The pity is I am really interested to read any articles about a link between Oestrogen and KC as mine (KC) has only really manifested itself as I have reached that "certain (old) age" !

Could you try and e-mail the pdf to me via the PM route - I could then save it to my hard drive and see if that is any more successful!

Thanks

[Vincent]

Pat, no hasty conclusion! My post was just for information Of course, I will send to Gareth or Anne any information which I have on the subject.
I will fix your problem with the pdf tomorrow.

Amitiés
Vincent

[Vincent]

Of course, I will send to Gareth or Anne any information which I have on the subject.

Oulala! Shame on me!: I forgot Mr John Smith...

[John Smith]

Shame on you Vincent!

No problems

[Vincent]

I always thought that admins were the best... It’s now confirmed ! They are never “rancorousâ€