Glaucoma is probably the most soul destroying disease veterinary ophthalmologists deal with on a day-to-day basis. It will cause blindness and discomfort and often ends in removal of the eye or occasionally in euthanasia of the patient.
Historically there have been a number of surgical techniques described to improve the retention of vision and comfort but these have a high failure rate and poor long-term outcomes. The use of shunts where a drainage tube is placed into the anterior chamber of the eye and the aqueous allowed to drain to an extraocular space can provide useful short to medium term results but invariably end up as failures in the long-term. Another reconised technique is to try and destroy the ciliary processes (responsible for fluid production in the eye) with externally applied heat (laser) or cold (cryoprobes). This can be effective at reducing intraocular pressures but with significant side effects such as uveitis and poor long-term outcomes.
The latest described technique takes the theory of cliliary body destruction but in a more controlled and targetted manner to reduce the side effects and increase long-term success rates. By using a tiny endoscope we are now able to view inside the eye and aim the laser directly at the ciliary processes rather than aiming blindly through the outside of the eye. Not only can the tissue be targetted accurately but the effect of the laser can be assessed so that effective levels of high intensity heat can be applied to the tissue.
Initial data suggests that the success (retention of vision and comfort over a year) approaches 75%. This compares very favourably with other treatment modalities.
We were the first private clinic in the UK to offer this service and have now performed this surgery on over 75 eyes within the last 32 months with similar degrees of success. Long-term we envisage this treatment as the gold standard for glaucoma surgery in companion animals and we are at the forefront of investigating its use in horses.