Posted on 11th May, 2023 at 6:03:51 AM
In my clinic yesterday a very nice lady, highly educated, came to see me for a routine eye check. She was diabetic so needed a retinal check annually and had conscientiously turned up for this. In our way of working, irrespective of what you come for (your ‘presenting complaint’) you get a full and thorough eye check, which she had. Her spectacle prescription had changed, so that was prescribed. On asking about family history she volunteered that her mother had glaucoma and her aunt may have had it (but she was not sure). Her eye pressure (intraocular pressure, IOP) was 26 in either eye, checked by the gold standard method (Goldman applanation tonometry – many clinics rely on non-contact tonometry – the ‘air puff’ which is less accurate), and her optic discs looked suspicious of glaucoma. Happily, she had no signs of diabetic retinopathy. So although I could reassure her of the diabetic retinopathy issue, the reason she had come to me in the first place, I requested further tests to establish or rule out glaucoma. A standard glaucoma workup these days includes perimetry (visual field test), CCT (Central corneal thickness – as this can influence IOP readings), and a study of the optic nerve head, using one of mainly three modalities – the commonest today is probably an optical coherence tomogram – OCT – but a GDX or HRT (Heidelberg Retinal Tomogram) are also used. The particular choice of optic nerve study depends on local availability, the familiarity of the doctor with a certain technology, and his/her confidence in that technology. So I ordered a Perimetry, CCT, and an OCT RNFL (Optical Coherence Tomograph of the optic nerve head measuring the Retinal Nerve Fibre Layer). Glaucoma is well known as the ‘silent thief of vision’, patients are asymptomatic until they lose a lot of vision, and any damage done is irreversible, treatment can only realistically aim at preserving what is not lost already and at slowing down the progression of loss if the further loss cannot be stopped. It is a bit like me taking my blood pressure and cholesterol tablets every morning – they do not make me feel better, but I know that they reduce the risk of serious adverse events in the future, so I take them and see my physician every few months to have my parameters checked.
Whilst I was doing the exam and explaining the need for further tests she was quite understanding, but the final question which popped out was – “Why does everyone need further tests when one goes to see a doctor”. I was taken a bit aback, as I had just spent over 15 minutes telling her why these were needed. She agreed to have them and will come back with results (hopefully- unless she decides to go ‘doctor shopping’ – which is an issue probably better addressed in a separate article). After the busy clinic, when I got back home – her question kept popping back into my mind - “why does everyone need further tests when one goes to see a doctor”.
I thought why did she ask this, did she believe that doctors order unnecessary tests? Did she believe that doctors make money from ordering tests? Did she believe that I only wanted to generate further visits (and fees)? Modern medicine is a business, and none of these questions are illegitimate.
At the same time modern medicine is highly technology dependent, so tests are an inevitable part of it, unless we have the tests, we cannot be certain of a diagnosis. Yes, some doctors do make money from ordering tests, but for the vast majority that is not the motivation for ordering tests, tests may make you some money, but the biggest thing which makes doctors money is treating a patient and getting them well (or better) – from a purely business point of view, this is more lucrative, a bigger earner, and the best advertising a doctor can have, than ordering tests will ever be. So a doctor who spends time with the patient and explains why tests are needed is in all probability doing this, because it is in the patient's best interests, not because the doctor gets something out of it.
