Jetrea, aka ocriplasmin, manufactured by Thrombogenics is FDA approved to enzymatically induce, or create, a posterior vitreous detachment. By creating a PVD, several retinal diseases might be treated without conventional eye surgery such as vitrectomy.
I recently started using Jetrea for treatment of vitreomacular adhesion, coined VMA. This is also known as vitreomacular traction (VMT). It is not dissimilar to an epiretinal membrane where the surface of the retina is affected by the overlying vitreous.
Most patients with VMA have mild vision loss, say 20/40 to 20/80, and may or may not have symptoms of metamorphopsia. Metamorphopsia is the fancy term for distortion.
The OCT demonstrates typical findings; minimal vitreoretinal adherence but only on the fovea. Unlike epiretinal membranes, the affected area appears solely at the foveal center.
Patients with VMA have subtle changes on examination. There is no obvious ERM, no cystic macular edema, but there may be subtle elevation of the macula and/or blunting of the foveal reflex (it’s not as shiny looking).
My usual routine is to discuss the options for treating VMA; observation (do nothing), vitrectomy or Jetrea. For those who choose Jetrea (ocriplasmin), I’ll give the appropriate informed consent (chance blindness from endophthalmitis or retinal detachment) and prescribe topical antibiotics for use 4 days prior to the scheduled day of the intravitreal injection.
This is the same regimen I prescribe for all patients receiving intravitreal injections. In theory, pre-treating with antibiotics may further reduce the chance of infection.
On the day of injection, patients are dilated and then “marinate” for about 20-30 with a cotton applicator soaked in lidocaine solution. The applicators are usually changed every 10 minutes. Most patients require only a 20 minute “numbing period.”
The vial of Jetrea is kept frozen up until the injection is delivered. Thrombogenics recommends thawing the solution just prior to anticipated injection. The small amount of diluent thaws rapidly, rolling the vial between your hands can hasten the process.
The injection kit has all the needles and syringes needed for injection. Add 0.2 ml of 0.9% NaCl to the thawed Jetrea (Ocriplasmin) and swirl.
Withdraw most of the solution into a syringe, shake out bubbles and expel all but 0.1 ml of the diluted solutions of Jetrea.
0.1 ml of Jetrea is injected per treatment.
Immediately after injection, I’ll often recline the patient for 30 minutes. In theory, this may allow the injected solution to accumulate faster on the macula. Given the relatively short half-life of the enzyme, this may make sense.
While this is a relatively new treatment, treatment patterns are certainly going to vary, but the head reclining makes practical sense to me.
What Does this Mean?
Jetrea (Ocrisplasmin) represents a novel non-surgical approach to treat VMA/VMT, macular holes and certain epiretinal membranes. Jetrea works by enzymatically cleaving the adherent vitreous from the retina. By simply causing a PVD, vitreomacular traction may often be cured…without an operation.
This has implications for the treatment of other conditions such as certain macular holes and epiretinal membranes, classically treated with surgery.