Effect of Intraocular Enoxaparin on Postoperative Fibrosis in Juvenile Rabbit Model of Lensectomy
Narrative Responses:
Purpose
We seek to determine the effect of pharmacologic intervention with enoxaparin on postoperative intraocular inflammation and fibrosis.
Methods
All experiments are approved and in compliance with Animal Care Committee at the University of Illinois. Juvenile (6 week old) New Zealand White rabbits underwent preoperative dark and light-adapted ERGs under sedation with intramuscular Ketamine and Dexmeditomidine. Under anesthesia with Ketamine and Xylazine, unilateral cataract extraction without intraocular lens placement was performed. After closure of all wounds with 10-0 nylon suture, Balanced Salt Solution (control) or 10mg of Enoxaparin was injected into the anterior chamber of the operated eye. Optical Coherence Tomography and anterior chamber fibrin formation were evaluated daily from 2 to 7 days postoperatively and then weekly.
Results
Lensectomy in a juvenile rabbit induces fibrin clot formation in the anterior chamber reducing signal strength in 60% of control rabbits (3/5) between postoperative days 2 through 4. In contrast, none of the 3 rabbits with Enoxaparin injection developed a postoperative fibrin clot or membrane. Comparison of the ratio of the operated eye/unoperated eye signal strength in control or Enoxaparin-treated rabbits showed that eyes injected with Enoxaparin had an increase in signal strength ratio compared to controls. Electroretinogram (ERG) studies showed no significant difference comparing case and control groups before and after lensectomy.
Conclusion
Our data indicate that in a rabbit model of lensectomy, 10mg of Enoxaparin injected into the anterior chamber after lens extraction may reduce the formation of fibrin clots and improve optical clarity without toxic effects to retinal function by ERG.