Surgical management of equine ocular setariosis: A review of 10 cases

The study was conducted on ten horses for brought for treatment of ocular setariosis. All the animals had history of continuous lacrimation with a visible floating worm in one eye. In all the animals, supraorbital, auriculopalpebral and retrobulbar nerve blocks were performed using 2% lidocaine and 0.5% proparacaine was instilled in the affected eye. An 18G sterile hypodermic needle attached to a 20 mL syringe half filled with normal saline was inserted into the anterior chamber of the eye at 6–8 O'clock position of the cornea approximately 1 mm away from the limbus. The needle was manoeuvred to bring it closer to the migrating parasite, and the parasite was aspirated out when it was nearest to the needle. In one case, the eye worm could not be retrieved with needle paracentesis. Therefore, a nick incision was made at 68 O’ clock position using a No. 11 BP blade to remove the worm. All the horses showed uneventfull recovery. The collected worms were identified as Setaria equina.