Dexamethasone Intravitreal Implant for the Treatment of Retinal Vein Occlusion (82)

Inclusion criteria

• Patients with decreased visual acuity as a result of clinically detectable macular oedema associated with either 1. central retinal vein occlusion (CRVO) or 2. branch retinal vein occlusion (BRVO) who are not clinically suitable for laser treatment including patients with dense macular haemorrhage or patients who have received and failed on previous laser treatment
• Eligible patients will have best-corrected visual acuity of 6/12 or worse in the treated eye due to macular oedema in the doctor’s opinion
• Retinal thickness in the central subfield (as measured by optical coherence tomography) has to be greater than 300 μm in the eye to be treated or there must be fovea-involving oedema reducing vision

Exclusion criteria

• spontaneous improvement of vision of 10 letters or more from time of listing to point of injection – consider withholding therapy
• consider laser in BRVO as first line (SMC guidance) and use dexamethasone implant (Ozurdex ®) for non-responders
• the presence of a clinically significant epiretinal membrane, macular ischaemia, active retinal or optic disc neovascularisation (relative contraindications) consider alternative interventions
• presence of rubeosis iridis (relative contraindication – treat rubeosis first with PRP +/- anti-VEGF)
• any active infection
• aphakia or anterior-chamber intraocular lens (relative contraindication)
• glaucoma or current ocular hypertension requiring more than 1 medication to control IOP in the eye to be treated, or a history of steroid-induced IOP increase in either eye (relative contraindication)
• administration to both eyes concurrently
• hypersensitivity to the active substance or to any of the excipients as listed in the product literature (SPC)

A topical disinfectant such as povidone-iodine should be applied to the conjunctival fornix.

Following topical anaesthesia (below) as well as applied to the periocular skin including the eyelids and left in contact with the skin for 3 minutes before an eyelid drape and speculum are then applied.

Use local anaesthesia – either topical Proxymetacaine and/or Oxybuprocaine and consider additional subconjunctival local anaesthetic e.g. Lidocaine 1% at the injection site.

Whilst the injection is usually administered in a suitable clean room, following the local SOP, consideration can also be given to using an operating theatre with an appropriate operating microscope until the doctor administering the drug is more comfortable with the injection technique or if a clean room facility is unavailable.

Follow up and investigate patient according to Royal College of Ophthalmologists published guidelines on the management of retinal vein occlusion (see website for details).

Patients will be reviewed within 4 weeks of dexamethasone implant (Ozurdex ®) injection, at 2 months, and then on a 2 monthly basis to the 6 month point, and then 3 monthly until stable. Retreatments may be given at approximately 6 months from initial treatment or after 4 months if the clinician considers appropriate.

Criteria for retreatment (any one or combination of the following):

1. Loss of BCVA of >5 letters from best achieved
2. OCT thickness >300μm or persistent oedema involving the fovea
3. Increase in OCT thickness of >50 μm from thinnest measurement

Criteria for no further treatments:

1. Development of ischaemia and/or neovascularisation requiring laser therapy
2. Development of a significant steroid response (>35mmHg on more than one IOP lowering medication)
3. Patients who experience a deterioration in vision, which is not slowed by dexamethasone implant (Ozurdex ®), should not be retreated