OCT Retina Scan: What It Shows and Why It Is Done
Quick answer: An OCT (optical coherence tomography) retina scan uses light to take detailed cross-section images of the retina and optic nerve, showing their layers in micrometre detail. It is quick, painless and uses no radiation or contact with the eye. It helps detect and monitor macular degeneration, diabetic macular swelling, macular holes, epiretinal membranes and glaucoma-related thinning of the nerve fibre layer.
Due an eye test? Book at Vision Concern Lazimpat, Boudha-Tushal or Makalbari (eye test NPR 400).
What OCT can detect
- Fluid or swelling in the macula (for example in diabetes or wet AMD).
- Macular holes and epiretinal membranes (macular pucker).
- Changes of age-related macular degeneration.
- Thinning of the retinal nerve fibre layer and optic nerve changes in glaucoma.
- Response to treatment, such as anti-VEGF injections.
What happens during the scan
You rest your chin on the machine and look at a target light while the scan runs for a few seconds per eye. Your pupils may be dilated with drops for a clearer image, which can blur near vision and make you sensitive to light for a few hours.
OCT vs other tests
OCT shows cross-sections of the retina; retinal photographs show its surface; angiography with dye shows blood flow. An MRI of the orbits is a different test for the eye socket, muscles and brain pathways. OCT results are interpreted alongside a full eye examination.
How Vision Concern can help
Vision Concern is an eye-examination clinic and optical shop in Kathmandu with branches in Lazimpat, Boudha-Tushal and Makalbari. Its optometrists can examine your eyes, explain findings, update your glasses or contact lenses, and refer you to an eye specialist when medical or surgical care is needed.
Frequently asked questions
Is an OCT scan safe?
Yes. It uses low-power light, involves no radiation and does not touch the eye.
How long does an OCT scan take?
Usually a few minutes for both eyes, plus waiting time if dilating drops are used.
Can OCT diagnose glaucoma on its own?
No. It measures nerve-layer thickness, which is combined with eye pressure, optic nerve examination and visual field tests.
This guide is general education and does not replace an eye examination or advice from your treating doctor.
Yes. Many visitors, particularly from Bangladesh and West Bengal (Kolkata), come to Nepal for cataract, retina, or other eye surgery at a hospital and also want new glasses, a general eye exam, or contact lenses at the same time, before or after their procedure. Vision Concern is an optical and eye-examination clinic, not a surgical hospital, so we work alongside hospitals such as Tilganga: we are happy to see you for glasses, contact lenses, or a routine check-up either side of your surgical treatment elsewhere.
No conversion is needed. Eyeglass prescriptions from Germany, France, the UK, the USA, China, Russia, and almost every other country use the same international format, SPH (sphere), CYL (cylinder), and AXIS, measured in diopters. Our opticians read this directly, so you can bring your prescription paper, a photo of it on your phone, or simply your current glasses, and we will use the same values. If your prescription is more than a year or two old, we recommend a quick, free re-check before we make your new pair.
Yes. Above roughly 3,000 metres, UV exposure increases sharply because of the thinner atmosphere and reflection off snow, and ordinary sunglasses (category 2-3) do not block enough UV to prevent snow blindness (photokeratitis). We recommend glacier glasses or category-4 sunglasses with side shields, and can fit these with your own prescription if needed. Vision Concern offers ZEISS polarized, UV400-certified sunglasses with prescription lenses, which we can prepare before you set off on your trek.