Cataract surgery should be considered when your cataract is meaningfully affecting your quality of life — not when it reaches a specific grade on examination, and not when it is 'ripe'. Modern surgical techniques allow safe removal at any stage of cataract development, and delaying surgery when vision is functionally impaired offers no clinical benefit and can carry real risks.
What Does 'Functionally Impaired' Mean?
A cataract is functionally significant when it limits your ability to do things that matter to you. Common examples include difficulty reading even with up-to-date glasses, struggling to drive — particularly at night due to glare and halos around headlights — finding it hard to recognise faces or follow a television programme, problems with work tasks that require clear vision, and difficulty navigating safely in unfamiliar environments.
Your ophthalmologist will measure your visual acuity, but a number on a chart is only part of the picture. A person who reads extensively, works with fine detail, or drives frequently may be significantly impaired at a level of visual acuity that another person finds acceptable. The functional conversation — how your vision is affecting your daily life — is at least as important as the clinical measurement.
Are There Risks to Waiting?
Yes. While minor cataracts can safely be monitored, allowing cataracts to advance significantly before surgery can cause problems. Advanced (hypermature) cataracts become harder to remove and carry a modestly higher risk of surgical complications compared to less mature lenses. For older patients, the vision impairment associated with cataracts is a meaningful risk factor for falls and associated injuries — a leading cause of hospitalisation in the elderly. Impaired vision also increases the risk of medication errors. Difficulty distinguishing objects and faces can cause social withdrawal and depression.
On the other hand, there is no benefit in operating before a cataract is causing problems. Surgery should be timed to when it genuinely improves your function and safety.
Are There Clinical Criteria Used by Surgeons?
In Australia, Medicare requires that cataract surgery be clinically indicated. Your ophthalmologist will assess several factors: the degree of cataract on slit-lamp examination, your best corrected visual acuity, the impact on your daily activities (recorded in your consultation notes), whether other eye conditions may be affecting vision, and any driving or occupational requirements.
For patients who hold an Australian driver's licence, the standard requires a visual acuity of at least 6/12 in the better eye with both eyes open, with or without glasses. A cataract that threatens this standard creates an urgent clinical and legal imperative to address it. For commercial drivers and heavy vehicle operators, the requirements are stricter still.
Does Timing Differ for Patients with Diabetes?
Yes. Patients with diabetes should be aware that cataracts can develop earlier and progress more rapidly than in the general population. Additionally, cataract surgery itself can temporarily exacerbate diabetic macular oedema — a swelling of the central retina — in the post-operative period. For this reason, diabetic patients benefit from having their diabetic retinopathy status assessed and optimised before surgery. Well-controlled blood glucose levels in the weeks leading up to surgery are associated with better outcomes. If you have diabetes and cataracts, discussing the timing with an ophthalmologist who understands both conditions is particularly valuable.
When Both Eyes Are Affected
If cataracts are present in both eyes — which is common, as cataracts are typically bilateral — surgery is almost always staged: one eye is operated on first, and the second eye is done 1 to 4 weeks later. This allows the surgeon to refine the lens power calculation for the second eye based on the outcome of the first, and allows the first eye to recover before the second is operated on. True simultaneous bilateral cataract surgery (ISBCS) is occasionally performed in very specific circumstances but is not standard practice in Australia.
What to Expect at Your Consultation
At Northern Eye Consultants, your ophthalmologist will perform a comprehensive assessment including slit-lamp examination, best corrected visual acuity testing, and a dilated fundus examination to assess the health of the retina and optic nerve. If surgery is recommended, optical biometry measurements are taken to calculate the precise lens power needed. You will have a thorough discussion about your lens options, the expected outcome, and the procedure itself. A referral from your GP or optometrist is required to attend. Please contact our rooms on 03 9466 8822 or speak to your referring practitioner to arrange an appointment.