Crosslinking of scleral collagen in the rabbit using glyceraldehyde.
OBJECTIVE
To strengthen rabbit sclera in vivo using chemical crosslinking with glyceraldehyde for a scleral-based treatment of progressive myopia.


METHODS
Department of Ophthalmology, Martin-Luther-University, Halle, Germany.


METHODS
Five chinchilla rabbits were treated with sequential sub-Tenon injections of 0.15 mL 0.5 M glyceraldehyde into the superonasal quadrant of the right eye 5 times during 14 days. The rabbits were humanely killed and biomechanical stress-strain measurements of scleral strips from the treatment area were performed and compared with nontreated contralateral control sclera using a microcomputer-controlled biomaterial tester. The treated eyes were examined histologically by light microscopy to exclude possible adverse effects.


RESULTS
Following the crosslinking treatment, the ultimate stress was 15.8 MPa +/- 6.0 (SD) versus 3.1 +/- 0.3 MPa in the controls (increase of 409.7%; P<.02), the Young modulus was 129.6 +/- 53.7 MPa versus 11.5 +/- 1.8 MPa in the controls (increase of 1027%, P<.01), and ultimate strain was 19.8% +/- 2.6% MPA versus 38.2% +/- 5.1% MPA in the controls (decrease of 48.2% P<.05). Histologically, mild side effects were found in the peripheral cornea adjacent to the treatment area, with some inflammatory infiltrate and moderate loss of keratocytes.


CONCLUSIONS
Glyceraldehyde crosslinking of scleral collagen increased the scleral biomechanical rigidity efficiently. Glyceraldehyde can be easily applied by sequential parabulbar injections. There were no side effects on the retina, so the new method might become a treatment modality for strengthening scleral tissue to prevent progressive myopia.
Wollensak
Gregor
G
Department of Ophthalmology, Martin-Luther-University, Halle, Germany. gwollens@hotmail.com
Iomdina
Elena
E
D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004547:Elastic Tissue / Q000378:metabolism; D005985:Glyceraldehyde / Q000494:pharmacology*; D006031:Glycosylation; D008297:Male; D009216:Myopia / Q000188:drug therapy / Q000378:metabolism; D011817:Rabbits; D012590:Sclera / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology
D003432:Cross-Linking Reagents; D005985:Glyceraldehyde; D003094:Collagen