Combined CRVO with disc new vessels in a patient about to leave the country
A 57-year-old man with a 12-year history of type 2 diabetes (HbA1c 9.4%), hypertension and hyperlipidaemia presents with a 5-day history of painless loss of vision in the right eye. He takes metformin, gliclazide, perindopril, atorvastatin and aspirin 75 mg. Right VA is 6/36, left 6/6. Right IOP is 16 mmHg. Dilated fundoscopy of the right eye shows haemorrhage in all four quadrants involving both superficial and deep retina, dilated tortuous veins, cotton-wool spots, optic disc swelling, and new vessels at the disc and along the superotemporal arcade. The left fundus shows mild non-proliferative changes only. Gonioscopy and iris examination were not documented at this visit. He works as a site engineer and is booked to fly to a project in a country with limited ophthalmology cover in 10 days; he asks whether a single injection will 'fix it' before he goes.
1. How do you interpret this picture, and which questions must be answered before you commit to a treatment plan?
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The picture is a central retinal vein occlusion - four-quadrant haemorrhage, venous tortuosity, disc swelling - occurring in a diabetic who may already have proliferative disease. New vessels at the disc and along an arcade in this context usually indicate combined CRVO with a very high ischaemic drive. Whether the NVD is pre-existing PDR or new CRVO-driven neovascularisation changes the prognosis, but not the fact that ischaemic retina needs ablating urgently.
Questions that decide the plan:
- Is there neovascularisation of the iris or angle? Gonioscopy and an undilated slit-lamp view of the iris were not documented. If NVI or NVA is present, this is impending or established neovascular glaucoma, risk is measured in days to weeks, and complete panretinal photocoagulation must be finished before he flies. Missing NVI is the one thing that converts a visually impaired eye into a painful, blind one.
- What follow-up will actually happen? Anti-VEGF acts fastest but demands review at 4-weekly intervals for injection, IOP and traction. If he is going somewhere that cannot deliver that, any plan whose safety depends on monthly review is not a plan.
- Is the macular oedema centre-involving on OCT? This determines whether there is vision worth treating and modifies how you sequence PRP, since dense PRP can worsen oedema.
2. Given his travel plans, would you treat with intravitreal anti-VEGF, panretinal photocoagulation, or both? Justify your sequencing.
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Do not give one injection and send him away.
- PRP is the definitive treatment for the proliferative component: durable, one-off, deliverable in two or three sessions over the next 7–10 days and complete before departure.
- Anti-VEGF monotherapy is the wrong choice here precisely because of his travel. Regression is rapid but transient, and without review he risks a 'crunch' phenomenon with rapid fibrosis, tractional detachment, an IOP spike and silent progression of neovascular glaucoma.
- Anti-VEGF as an adjunct is reasonable if there is florid disc neovascularisation or NVI and you want regression before laser or before the flight - but only with a guaranteed review before departure and clear written instructions on where to be seen abroad.
- Sequence around the macula: if OCT shows centre-involving oedema, consider anti-VEGF first, or PRP that spares the fovea with later focal laser, because dense PRP can aggravate macular oedema.
- If NVI or NVA is found, treat as neovascular glaucoma: complete PRP urgently, anti-VEGF for rapid regression, topical IOP-lowering agents, and counsel that filtration surgery or a drainage device may be needed - a legitimate reason to postpone the trip.
Give him a written summary of what has been done and what must be checked while he is away, and copy it to his GP.
3. What systemic evaluation, medication review and communication would you arrange?
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Systemic work-up:
- Blood pressure - the most important modifiable driver; a CRVO is often the first evidence of poor control.
- HbA1c and renal function (eGFR, urine albumin:creatinine) - 9.4% is poorly controlled, and renal impairment will limit later options.
- Lipids and formal cardiovascular risk assessment - a CRVO is a marker of systemic vascular disease, so primary care follow-up matters as much as the eye clinic.
- Sleep apnoea screen if there is snoring or daytime somnolence - an under-recognised association.
- No routine thrombophilia or JAK2 screen at 57 with this risk-factor profile; reserve it for young patients, bilateral or recurrent occlusion, or an atypical picture.
Medication review:
- Continue aspirin. There is no convincing evidence that it causes or worsens vitreous haemorrhage, and stopping it raises cardiovascular risk.
- Do not start anticoagulation for the CRVO - it does not improve visual outcome and adds bleeding risk.
Communication: a written summary for the GP and, if possible, a named contact abroad; explicit instructions that new pain, redness or further visual loss require urgent review. Counsel him about the fellow eye, and document gonioscopy, IOP and iris findings at every visit for at least 6 months, because neovascular glaucoma can present late even after adequate PRP.