Ocular Trauma – How do I Know if the Eye Can be Saved?
Christa Corbett, MS, DVM, DACVO
With the active summer season approaching, trauma cases will be on the rise. Ocular trauma can be very intimidating but it’s important to establish whether the eye and/or vision can be saved or whether enucleation is the most humane option. This article will focus on the more common types of ocular trauma, and try to provide a framework to understand how best to treat these cases. The first and most important step to any trauma case is obtaining an accurate history. Blunt vs. penetrating trauma are regarded differently so if the incident was witnessed it can be very helpful to know the offender.
We will start with blunt trauma, and this refers to any blunt object moving towards the eye at a high speed such as running into a tree, kicked by a horse, playing ball in the yard, etc. In general, blunt trauma carries a worse prognosis for vision than penetrating trauma because the globe is hit at high velocity resulting in shock waves radiating through the eye. Consider the analogy of getting hit by a bus vs. being stabbed by a knife. With such a trauma the intraocular structures are at risk for shifting, tearing and dislocating. Most patients who experience blunt trauma present with swollen periocular tissues and hyphema. Always remember to do a full physical examination including skull/oral palpation to ensure that there are no skull/orbital fractures or dislocation of the jaw. If you determine that the bones are intact and this is merely a soft tissue injury, then the best thing you can provide is medical therapy and time. Unfortunately there is no emergency surgery or extensive treatment that we can offer blunt trauma cases, as the intraocular damage is not repairable. Mild, blunt trauma cases may regain vision with time, but the prognosis for return of vision in most patients with significant hyphema is grave. The goals of medical therapy include:
- Pain control (Opioids, Gabapentin, oral NSAID)
- Anti-inflammatory therapy (Topical and oral NSAID/Steroid)
- A topical antibiotic if there is corneal ulceration
- E-collar to protect against self-trauma
Patients should be rechecked after 5-7 days of medications, by then the swelling and inflammation should have improved and it is easier to determine the extent of damage. If vision has not returned, our focus then shifts towards keeping the patient comfortable. If the patient remains blind and is still experiencing discomfort, then enucleation is likely the best option.
The next type of trauma to consider is penetrating trauma. Examples of penetrating trauma we see frequently include a cat scratch, running into a thorn, or projectile objects such as shattering glass. Though there are surgical options to preserve the eye, it is important to determine prognosis to know if emergency surgery is possible. Below are some criteria to help determine prognosis for these cases:
- Location of the laceration – A pure corneal laceration is optimal, if the laceration crosses the corneoscleral limbus then the intraocular damage may be too extensive to repair.
- Size of the laceration – A smaller defect carries a better prognosis for corneal repair.
- Depth of the laceration – Lacerations limited to the cornea and anterior chamber carry a good prognosis. Lacerations involving the iris, ciliary body or lens range from fair to grave prognosis depending on severity, and may not be surgically repairable. Cases with lens lacerations would require lens removal (e.g. cataract surgery) at the same time as corneal repair.
- Presence of hyphema – Hyphema can occur with any penetrating trauma, but if this is paired with a laceration that you suspect was deep or crosses the corneoscleral limbus then this could imply damage to the ciliary body and may not be surgically repairable.
- Time between initial injury and presentation to an ophthalmologist – As you would expect, the prognosis for vision worsens if surgical repair and/or appropriate medical intervention are delayed.
If you feel that a case of penetrating trauma may be a surgical candidate, please call your local Specialty and Emergency Clinic to inquire about emergency Ophthalmology coverage. If you feel that your patient is not a surgical candidate, then enucleation is recommended as medical treatment is not effective for most cases with full-thickness lacerations. Ultimately our primary goal in these cases is to make sure that the patient is stable with no other signs of traumatic injury to the head/body, and to initiate pain control while determining the best course of action.
Christa Corbett, MS, DVM, DACVO