Due to the rarity of incidence, there isn’t a huge amount of literature or data to confirm with 100% accuracy what the best protocol is to treat this complication. It is however worth noting that even specialist centres are not equipped or highly knowledgeable in the treatment, so referral to such may be futile and a waste of valuable time. For this reason, the treating clinician is going to be the best person to deal with the issue, in addition, hospital emergency departments do not stock hyaluronidase as we do, further highlighting that the injector will be the best person to resolve the issue within the most effective time frames. It will be most effective in the first 30-45 minutes of the incidence happening, after this time at the very least hyalase if given later will assist in preserving the health of the muscle and surrounding skin.

Due to the lack of evidence-based knowledge we have surrounding diagnosis and treatment for this complication, the highest of importance must be placed on prevention, with this said, there are seven ways that clinicians have identified as the most effective way of dealing with a patient that is experiencing blindness:

Goal 1: To dissolve the Embolus to allow better perfusion of the retina.

This can be done in the following ways:

• SUPRAORBITAL HYALASE; perivascular injections into the superior orbit
• Shown to be effective in animal studies with a time frame of 97 minutes
• Technique rely on diffusion of the product through the artery walls, but is one of the safer options in terms of affected anatomy
• Won’t be effective if embolism is affecting the central retinal artery

• RETRO ORBITAL HYALASE – most talked about and highly regarded for effectiveness for central retinal and ophthalmic artery
• Technically more difficult that the above
• Usually administered far too late after procedure to know if cold have helped
• Animal studies give success with the time frame of 30mins

• INTRAVITREAL HYALASE as a suggestion but no recorded data of this strategy

Goal 2: Reduce vessel resistance of blood flow into the eye

• Nitrates which dilate veins and arteries
• Sildenafil: shown to induce vasodilation in the eye (Pache et al 2002)

Goal 3: Dislodge the embolus into a less damaging position

• Intraocular pressure changes involved in this technique, over a period of 1-3 hours
• Apply pressure to closed eye
• Eye indented with one finger at the depth of a few millimetres
• Push in & release, repeatedly for a second 2-3x

4 ways to reduce the intraocular pressure to increase blood perfusion

IV Mannitol among other things, promotes cerebral blood flow by making the blood thinner and offering microcirculatory resistance.

Anterior chamber paracentesis. It’s possible to reduce the intra- ocular pressure through this method of controlled drainage

Nitrates which dilate veins and arteries.
Sildenafil: shown to induce vasodilation in the eye (Pache et al 2002)

Hyperbaric oxygen increases the partial pressure of oxygen in the Plasma and can increase oxygen transfer to tissues by up to 16 fold (fleg byrn 2010)

Goal 4: Reduce the chance of blood clot making the problem worse

Aspirin
Anticoagulants
Reduce the chance of inflammation making blood perfusion worse Steroids
Increase oxygen delivery to the retina by hyperbaric oxygen, can increase oxygen transfer between tissues up to 16 times