Ocular emergencies (Proceedings)
Ocular emergencies [ER] have been written about extensively and there are many good texts to access. This discussion will serve as a reminder of the most common ER conditions with many photos to assist in recognition, some new and standard therapies, and indications for referral to a specialist.
Many of the flow charts illustrating what to do with a red eye are excellent and good references to review periodically. It's harder to mistakenly miss major problems if ophthalmic examinations are performed systematically.
The number one rule of ocular emergencies is to not forget the body to which the eyeball is attached. Look at the pet as a whole animal especially in cases of suspected trauma such as car accidents or dog fights. Pets that have disappeared for a few days and come home with an ocular problem also need to be evaluated systemically. Are they dehydrated, are they suffering from other systemic injuries, do they have normal temperature, pulse, respiration?We will discuss ocular ER cases most commonly seen:
Laceration: eyelids: The time from injury affects the healing ability and the bacterial load. As eyelids are well vascularized, only minimal debridement, even a couple of days after a laceration, is required. Culture and sensitivity may be warranted if more than a few days after the incident or if purulence is obvious. Owners may use an over the counter triple antibiotic ointment until the pet is examined. Cool pressure on the laceration may be tolerated to diminish hemorrhage and swelling. The degree of eyelid margin loss will determine if primary closure can be accomplished or if a rotational flap to compensate for margin loss will be required. Carefully evaluate medial eyelid lacerations for the potential for lacrimal puncta trauma. If a laceration is close or debridement may involve this area, place a stent of 2-0 nylon into the adjacent nasolacrimal duct until complete. This will allow identification if the duct is lacerated and may remain in place for a week post repair to maintain the duct integrity. It is important to evaluate the entire globe if the laceration crossed the eyelid margin. Concussive injuries causing uveitis, lens luxation, or retinal detachment may need to be addressed. If severe, the potential for intracranial damage may also need to be monitored and a full neurologic examination should be performed. Laceration of the globe itself may necessitate suturing of the cornea or sclera in addition to the possible need for further diagnostics such as ultrasound.
It is important while suturing the eyelid margin that attention to proper alignment is observed. Large or hemorrhagic lacerations may benefit from palpebral conjunctival sutures with 6-0 vicryl. Eyelid margins may be sutured with a figure 8 or simple interrupted pattern as long as care is taken to tuck away the suture ends such that corneal rubbing is impossible. The use of Elizabethan collars is of benefit with atopy dogs, young dogs, or nervous dogs. Take care though to not ignore pruritis that may indicate sutures were tied overly tightly with excessive swelling, foreign bodies were missed, or sutures are rubbing.
Laceration: Cornea: If foreign bodies [FB] are present use 2-3 doses of topical anesthetic over 10-15 minutes to assure anesthesia. Superficial FB may be elevated with a 25g needle, bevel up, and care not to penetrate the cornea. Malacic corneal stroma should have cytology and culture and sensitivity performed. Topical fluroquinolone solution such as Ocuflox, Vigamox, or Zymar should be used at 1 drop every 6 hours. Autologous serum may also be of benefit in these cases with suspected melting. It may be of benefit to sedate to prevent further trauma if a foreign body is large, if it is penetrating into the eye, in preparation for referral. Systemic antibiotics and, if not contraindicated, prednisone, should be prescribed. Removal of a FB that penetrates the globe should be avoided until the pet is under general anesthesia and a veterinarian trained in intraocular surgery is available. Topical atropine once to twice daily initially may help decrease the chance of synechia but should be used with caution in breeds predisposed to goniodysgenesis and a risk of glaucoma. I rarely use this drug for more than one or two days. A short acting mydriatic such as tropicamide may be used for the first week twice a day instead.