Types of Eye Injuries

With all types of eye injuries, assess and document vision as soon as possible. If teleophthalmology is possible, initiate consultation. Avoid any of the interventions listed as “DO NOT” perform in the Eye Exam section of this CPG.

Following the treatment protocols listed below, protect the MWD’s eye from further injury, and prepare the MWD for medical evacuation (MEDEVAC) to a higher role of care, especially if surgical repair is indicated. Vision-threatening injuries should always be evacuated.

IMPORTANT! When protecting the MWD’s eye, DO NOT attempt to bandage or cover the eye. Make every attempt to keep the MWD from scratching the eye and periorbital area. An Elizabethan collar (e-collar) or similar device (such as a bucket) should be used. (See K9 Normal Clinical Parameters CPG.)

CHEMICAL INJURY

With this type of injury, epithelial defect(s) of the cornea or conjunctiva are typically noted. There may also be conjunctival hyperemia and chemosis.

Management

1. Begin irrigation immediately. Irrigate with normal saline or Lactated Ringer’s Solution (LRS). It is acceptable to use water or any neutral irrigation solution if saline or LRS is not available. A Morgan lens can be used, if available, or a nasal cannula hooked to intravenous (IV) tubing for continuous irrigation. Use a minimum of two liters for irrigation if unable to check pH. Some chemical injuries require up to 10 liters.

2. Apply topical anesthesia with tetracaine, proparacaine or lidocaine as needed to maintain MWD comfort during irrigation.

3. DO NOT try to neutralize acid with base, or base with acid.

4. Remove visible acidic or basic foreign bodies with a cotton-tipped applicator (CTA). Inspect conjunctival fornices and behind the third eyelid for retained foreign bodies. Irrigate or sweep the fornices with a CTA.

5. Assess and document vision if possible.

6. Stain with fluorescein and illuminate with cobalt blue light if available.

7. If superficial corneal ulcer (fluorescein stain positive), start a first line topical antibiotic such as:

- Neomycin/polymyxin B/bacitracin zinc ophthalmic ointment: ¼” strip into the affected eye(s) Q8 hours
- Tobramycin solution: 2 drops in the affected eye(s) Q6 hours

8. If stromal corneal ulcer (fluorescein positive with signs of infection), start second line topical antibiotic such as:

- Ofloxacin ophthalmic solution: 1 drop in the affected eye(s) Q6 hours

9. If no corneal ulcer is present (fluorescein stain negative), start topical lubricants:

- Eye lubricant ointment (preservative free is preferred): ¼” strip into the affected eye(s) Q6-8 hours

10. Provide sedation and analgesia:

- Trazodone (anti-anxiety): 3 – 7 mg/kg PO Q8-12 hours
- Gabapentin (sedation and pain): 5 – 10 mg/kg PO Q8-12 hours
- Carprofen (pain; NSAID): 2.2 mg/kg PO Q12 hours or 4.4 mg/kg PO Q24 hours
- Only in patients without history of kidney disease, liver disease and gastric ulcers. Stop immediately if patients show gastrointestinal clinical signs (e.g. vomiting or diarrhea).

11. Protect the eye and MEDEVAC the MWD if indicated based on clinical signs and consultation.

HYPHEMA

An MWD with this injury will have blood (can be clotted) in the anterior chamber. If the eye appears like an “8-ball” or “black ball,” this is blood filling the anterior chamber of the eye.

Management

1. Rule out an open globe injury.
2. Assess and document vision if possible.
3. If superficial or stromal corneal ulcer noted, treated as outlined under Chemical Injury section.
4. If no corneal ulcer is present, start topical steroid - Prednisolone acetate 1%: 1 drop in the affected eye(s) Q6-8 hours
5. Provide sedation and analgesia as needed (as outlined under Chemical Injury section).
6. Cage rest the MWD with head elevated 30 degrees, if possible.
7. Protect the eye and MEDEVAC if indicated based on clinical signs and consultation.

EYELID LACERATION

Note if the laceration involves the eyelid margin or the nasolacrimal system.

Management

1. Assess and document vision if possible.

2. Assess and treat any identified corneal ulcers as noted under Chemical Injury section above.

3. If no corneal ulcer is present, and unable to fully close the eyelids to protect the cornea, start topical lubricants.

4. Provide sedation and analgesia as outlined in the Chemical Injury section.

5. Seek teleophthalmology consultation with veterinary ophthalmologist or veterinary surgeon if possible.

6. Unless experienced, delay definitive repair for laceration involving the eyelid margin for surgery by an experienced veterinarian or veterinary ophthalmologist. DO NOT repair in the presence of an open globe injury.

a. If experienced, full thickness eyelid lacerations should be closed in two layers, with the MWD under deep sedation with local anesthesia or under general anesthesia. (See K9 Analgesia and Anesthesia CPG.)

b. First, close the deep layer consisting of muscle and subcutaneous tissue with 5-0 or 6-0 braided absorbable suture in a simple continuous pattern.

c. Next, close the skin. Monofilament absorbable or non-absorbable suture can be used, or the same suture that was used to close the deep layer can also be used. To align the eyelid margin, a figure-of-8 suture may be used to obtain correct apposition. If a simple interrupted suture is used at the eyelid margin, ensure that the suture tails do not rub the cornea.

NOTE: Larger suture sizes, such as 3-0 or 4-0, can be used in operational environments if smaller sizes are not available.

ORBITAL FRACTURE

This injury often occurs with blunt force trauma to the head, or with exposure to a blast. Always stabilize the K9 first if there are signs of head trauma or systemic manifestations of blast injuries before addressing orbital fractures.

There may be a step defect in the orbital rim (defect palpated resulting from fracture of bony outer edges of the eye socket), restricted eye movements, enophthalmos (affected eye is further back in the orbit compared to the opposite eye), hypoglobus (the affected eye is lower compared to the opposite eye), or subcutaneous or conjunctival emphysema.

Maintain high suspicion for an open globe injury.

Management

1. Urgent repair is required when clinical evidence of extraocular muscle entrapment with non-resolving bradycardia, heart block, nausea, vomiting, or syncope (oculocardiac reflex).
2. Assess and document vision if possible.
3. If superficial or stromal corneal ulcers noted, treat as outlined in the Chemical Injury section above. If no ulcers, start topical lubricants. Provide sedation and analgesia.
4. Consider systemic antibiotics (amoxicillin-clavulanic acid 13.75 mg/kg PO Q12 hours) if sinusitis or dirty wound.
5. Protect the globe and evacuate the MWD.

CORNEAL ABRASION

An epithelial defect will be noted on the cornea. There should not be any infiltrate (whitish opacity on the cornea). White or yellow infiltrates and stromal loss indicate infection or inflammation of the cornea. The cornea will have positive fluorescein uptake when illuminated with cobalt blue light if available.

Management

1. Administer medications as indicated in the Chemical Injury section above if superficial or stromal corneal ulcers are identified, along with systemic sedation and analgesia.
2. DO NOT use topical corticosteroids.
3. The MWD must not be able to rub or scratch the eye. An e-collar or similar device can be used. (See K9 Normal Clinical Parameters CPG.)

OPEN GLOBE INJURY

Mechanism

Lacerations from penetrating or perforating trauma, ruptured globe from blunt trauma.

Exam Findings

- Collapsed or severely distorted eye.
- Open wound, full-thickness corneal or scleral laceration.
- Shallow anterior chamber.
- Irregularly shaped or miotic pupil.
- Prolapse of intraocular contents outside the eye (dark tissue is iris or uveal tissue).
- Subconjunctival hemorrhage, especially if 360 degrees.

Management

1. Assess and document vision (specifically dazzle, and direct or indirect PLRs) when possible.
2. Early telemedicine consultation with 64F veterinarian or eye surgeon.
3. MEDEVAC the MWD for urgent surgical repair within 24 hours when possible.
4. Keep MWD fasted on cage rest. Elevate head 30 degrees if possible. Avoid any maneuvers that may increase IOP. Use caution with the use of collars or anything around the neck of an MWD that may cause an issue. Utilization of a harness is recommended, if available.
5. Start systemic antibiotics (amoxicillin-clavulanic acid 13.75 mg/kg PO Q12 hours).
6. Treat nausea and vomiting aggressively (ondansetron 1 mg/kg IV Q12).
7. Provide sedation and analgesia (see Chemical Injury section above). If additional pain management is needed, refer to the K9 Analgesia and Anesthesia CPG.
8. Remember, DO NOT:

- Put pressure on the eye.
- Attempt ultrasound of the eye.
- Attempt to repair, enucleate the eye or debride tissue.

INTRAOCULAR FOREIGN BODY (IOFB)

Mechanism

Various, but have high index of suspicion if blast injury, shrapnel, or metal-on-metal injury.

Exam Findings

Penetrating or perforating site(s) in the sclera or cornea or a hole in the iris. Findings may be subtle. If there is an intraorbital foreign body, it may be visible on exam or identified on diagnostic imaging such as radiographs or CT.

Management

1. Assess and document vision if possible and seek telemedicine consultation.
2. Protect the globe and MEDEVAC for urgent surgical repair within 24 hours if possible.
3. Keep MWD fasted on cage rest. Elevate head 30 degrees if possible. Avoid any maneuvers that may increase IOP.
4. Start systemic antibiotics (amoxicillin-clavulanic acid 13.75 mg/kg PO Q12 hours).
5. Treat nausea and vomiting aggressively (ondansetron 1 mg/kg IV Q12).
6. Provide sedation and analgesia as needed to maintain patient comfort. (Refer to K9 Anesthesia and Analgesia CPG.)
7. Remember, DO NOT attempt to remove the IOFB or put pressure on the eye.
8. For intraorbital foreign bodies, DO NOT remove impaled or resistant foreign bodies.

CORNEAL & CONJUNCTIVAL FOREIGN BODIES

Will most likely see the corneal or conjunctival foreign body on exam (but not always). If the foreign body is metallic, may see a rust ring.

Management

1. Suspected foreign bodies may be irrigated away or removed with a moistened CTA under topical anesthesia (such as proparacaine or tetracaine drops).

a. NOTE: Remember to inspect the conjunctival fornix and behind the third eyelid for retained foreign bodies. Irrigate or sweep with a CTA.

2. Start second line topical ophthalmic antibiotic: Ofloxacin ophthalmic solution: 1 drop in the affected eye(s) Q6 hours

3. DO NOT remove impaled or resistant foreign bodies.

4. Perform telemedicine consultation, protect the globe and MEDEVAC the MWD if foreign body cannot be removed easily with minor injury.

THERMAL BURN

- This injury is usually associated with a facial burn, eyelid burn, and eyelash loss.

Management

1. If unable to close the eyelids, start eye lubricant ointment to prevent eye exposure. Apply Q 2-4 hours.
2. Protect the eye and MEDEVAC the MWD if indicated based on telemedicine consultation.