Eyewatch, an Innovative Adjustable GDD for the Treatment of Glaucoma - in Vivo Results

PURPOSE: To report the in vivo results of a continuously adjustable glaucoma drainage device (GDD) in glaucoma surgery with rabbits. METHODS: Under general anesthesia, the AGDD was implanted on 12 white New-Zealand rabbits for duration of 6 months. The adjustable GDD was inserted under a scleral flap through a paracenthesis. Using an external control unit, the aqueous outflow through the GDD is continuously controllable by adjusting the resistance of the system. The contralateral eye was not operated and served as control. After sacrifice the eyes were collected for histology evaluation. RESULTS: The mean preoperative IOP was 11.1 +/- 2.4 mmHg. The IOP was significantly lower for the operated eye (6.8 +/- 2 mmHg) compared to the non-operated eye (13.1 +/- 1.6 mmHg) during the first eight days after surgery. When opening the AGDD from its fully closed to fully open position, the IOP dropped significantly from 11.2 +/- 2.9 mmHg down to 4.8 +/- 0.9 mmHg (p < 0.05). CONCLUSION: The new adjustable GDD eyeWatch can be easily implanted during glaucoma surgery to better address the hypotony phase encountered after placement of a seton tube. The easy adjustability of the resistance to aqueous humor overtime allows a more precise control of the postoperative IOP.