Biometry

Measuring Your Eye With Precision — Before Cataract Surgery

Before cataract surgery, your surgeon needs to know the exact measurements of your eye in order to select the perfect artificial lens for you. Biometry is the precise measurement process that makes this possible. Without it, even the most skilled surgeon cannot guarantee the right lens power — and the right lens power is what determines how well you will see after surgery.

What Is Biometry?

Biometry is a non-invasive diagnostic test that measures the key dimensions of your eye — including the length of the eyeball, the curvature of the cornea, and the depth of the anterior chamber. These measurements are fed into a specialised formula that calculates exactly which power of intraocular lens will give you the clearest possible vision after your cataract is removed. Modern biometry uses optical coherence technology or ultrasound to achieve measurements of extraordinary accuracy.

Why Are These Measurements So Important?

• Every eye is different — even your two eyes differ from each other in subtle but significant ways
• The wrong lens power can leave you dependent on strong glasses after surgery
• Accurate biometry is the single most important factor in achieving a great visual outcome
• It allows your surgeon to plan precisely for monofocal, multifocal, or toric lens placement
• It takes just a few minutes and is completely painless

What Happens During Biometry?

Step 1 — No Preparation Needed

You do not need any special preparation for biometry. No eye drops, no fasting, and no recovery time is required. You can drive yourself to the appointment if you wish.

Step 2 — Sitting at the Machine

You sit comfortably in front of the biometry instrument and rest your chin on the support provided. You are asked to look at a target light inside the machine and keep your eye still for a few seconds.

Step 3 — The Measurement

The instrument sends a beam of light into your eye and measures how long it takes to reflect back from the retina. From this, it calculates the axial length of your eye. The corneal curvature and other dimensions are measured at the same time.

Step 4 — Lens Calculation

Your surgeon reviews the measurements and uses them to calculate the ideal lens power for your eye. This decision is discussed with you before surgery so you understand exactly what to expect from your vision afterward.

Is Biometry Painful?

Not at all. Biometry is completely painless and non-invasive. The entire test takes only five to ten minutes per eye and leaves no aftereffects. You can continue your normal day immediately after the appointment.

Why Patients Trust RGC Eye Hospital

• Advanced biometry instruments for measurements of the highest possible accuracy
• Experienced specialists who interpret and apply results with surgical precision
• Biometry results are always discussed with you clearly before any procedure is planned
• Part of a thorough pre-operative assessment process that prioritises your best visual outcome