Ocular Emergencies
For those of you squeamish about gory eye pictures, this webinar could push you to your limits, but these are photographs from real case scenarios and demonstrate some of the ocular emergencies that we could face in practice. Pip Boydell led this veterinary webinar and cited a variety of cases giving valuable advice on how to diagnose and treat a number of emergency ocular conditions.
Pip’s first statement urged us to consider every ocular case as a potential emergency. If a client phones up with a puppy having been scratched on the eye one hour ago but now seems fine, should the receptionist still be asking these clients to come down? The answer is an overwhelming ‘yes’ with Pip passionately re-enforcing that every client expressing concern about their pet’s eye should be seen sooner rather than later.
The ‘scratched eye’ sceanario in a puppy is particularly relevant as Pip explains it is not uncommon for these puppies, if left untreated, to develop sight threatening glaucoma 10 days later. This glaucoma develops secondary to uveitis which will occur after any corneal trauma, and for this reason Pip always advises administering a drop of atropine into the affected eye even if there are no obvious signs of uveitis. Atropine also offers good pain relief and Pip expresses a preference for opiates to be used as additional pain relief rather than NSAIDs. This is because Pip also likes to use high doses of corticosteroids in uveitis cases which would be contraindicated if used concurrently with NSAIDs. Another tip offered by Pip is to consider other conditions if all the clinical signs of uveitis are present except for pain. Uveitis should never be ruled out under these circumstances but other conditions such as neoplasia should also be considered.
Melting ulcers were also discussed by Pip explaining how the cornea undergoes a progressive stromal dissolution due to the production collagenases often by damaged cells, an infection with Pseudomonas or exposure to an alkaline substance such as cement. The key treatment here is to wash the eye with anticollagenases which include EDTA, acetylcysteine, heparin and autologous serum. Pip’s preference is for acetyl cysteine which he administers initially every 5 minutes for 2 hours and then every 15 minutes for 8 hours.
Pip also warned us of the perils of dendritic ulcers in cats which can sometimes be very difficult to visualise, but if present, are pathogonomic for herpes virus. Topical steroids in these cases would often make matters worse and could eventually lead to the formation of a corneal sequestrum. In Pip’s opinion this is enough to deter the use of topical steroids in cats which should only be used where there is a definitive diagnosis and where steroids are the treatment of choice.
Other conditions discussed within the veterinary webinar included foreign bodies, perforation of the eye, glaucoma, acute blindness and proptosis which provided for most of the gory pictures at the start of the webinar. Incidentally if the pupil in the proptosed eye is constricted, this is a good indicator that this eye should respond well to treatment. However if the pupil is fixed and dilated, Pip used to advise the function in the eye would be very unlikely to return. However Pip has since had cases where function has returned so it may well be worth giving these patients some time.
When you do see an ocular case some of the challenge can be in deciding whether it is in fact an emergency? Does this case need to be referred to a specialist straight away, can I treat this case myself or can it wait till the next day? These are all the questions I find myself asking when I see an ocular emergency and this veterinary webinar organised by ‘The Webinar Vet’ not only provided a really interesting and watchable session, it also helped provided answers to many of my questions.