Equine Medical Guidelines – ophthalmology

Ulcers, uveitis and stromal stress

	Fluoroscene	Pupil size	Subpalpebral lavage system?	Antimicrobials	Atropine	Anti-inflammatories	Other therapy	Surgery
ULCERS	Positive	Variable	If difficult to medicate	Broad-spectrum q6-8h for ointment, q2h for aqueous. Consider antifungals.	Yes – use to effect for mydriasis	Flunixin IV if hospitalised, Bute PO in field	Serum/EDTA q2-4 for melting ulcers	Yes if: 1. Deep and centrally located 2. Melting 3. Desmetocoele
UVEITIS	Negative	Miosis	If difficult to medicate	None	Yes – q2h until pupil dilated then as needed	Flunixin IV if hospitalised, Bute PO in field	No	No
STROMAL ABSCESS	Negative	Variable	If difficult to medicate	Broad-spectrum q6 for ointment, q2 for aquous	Yes – use to effect for mydriasis	Flunixin IV if hospitalised	No	Yes – recommend for all

Ocular exams

1. Note any epiphora & blephrospasm
2. Examine the conjunctiva
3. Examine the cornea grossly
4. Examine the anterior chamber
5. Ophthalmoscopic examination
6. Fluoroscene stain
7. Other diagnostics

How to place a subpalpebral lavage catheter

1. Sedate heavily
2. Perform nerve blocks – auriculopalpebral & supraorbital (see below)
3. Infuse local anaesthesia at site of tube exit from the upper or lower lid and sites at which tube will be suture to the head.
4. Apply topical anaesthesia on eye – generous volume into eye every 1-2 mins for 3-4 applications
5. Using a non-sterile gloved hand under the eyelid, palpate most dorsal or ventral conjunctival sac close to orbit
6. Use introducing needle from kit, protect needle with finger as introduce to specified site and push through skin
7. Pull needle and tubing through and ensure footplate sitting flush against conjunctiva
8. Suture SPL tubing in place at several spots

How to perform nerve blocks

Supraorbital: Frontal nerve branch of trigeminal nerve

Locate supraorbital foramen (depression ) & inject 1ml lignocaine over foramen

Palpebral: **MOST IMPORTANT** Motor branch of facial nerve

Palpate nerve mid way along the zygomatic arch. Inject 1ml lignocaine over nerve