Health: Dear doctor

Lasers and safety

Q. I'm 46, moderately short-sighted, and considering having laser treatment to correct my vision, but I know little about the success rate or long-term effects of this procedure. My optician has only ever seen four patients who have had the treatment, two of whom were very short-sighted and had their vision improved rather than completely corrected, one whose sight was restored to perfection, and one who regained perfect focus, but with some peripheral blurring. However, my optician stressed that these might have been atypical cases.

His only reservation concerned the "experimental" nature of the procedure; having only been practised for around 30 years, the treatment may have unknown long-term effects. Do you know of any statistics on the overall success rate for this operation? And is there a professional body I could contact for impartial advice on the matter?

A. The most commonly used technique is called LASIK. A thin flap of outer corneal tissue is lifted up using a tiny instrument like a carpenter's plane. The laser is directed at the inner part of the cornea and the outer flap then flipped back into place. There are no stitches, minimal or no discomfort after the operation, and rapid recovery of vision with hardly any haziness. Up to 60% of those treated won't need glasses or lenses at all after the operation. There is no standard list of professionals offering LASIK, but an opthalmologist whom I asked said that Optimax, the largest organisation offering LASIK in this country, appears to meet the required standards.

Avoiding scars

Q. I have a basal cell carcinoma on the end of my nose. I am trying to find out the very best method of treatment with the least scarring. The only treatment available around here (Brighton, East Sussex area) is scraping, which will leave quite a scar. Would laser treatment (available in London) leave less of a scar and be effective? All my local enquiries on this matter seem to be hitting a brick wall of "don't know".

A. Basal cell carcinomas (BCCs), also known as rodent ulcers, need to be removed, because they tend to enlarge and eat away at surrounding tissues. The British Association of Dermatologists recommends seeing a specialist for BCCs on and around the nose, rather than letting your GP remove them, because they tend to recur unless fully destroyed. They can be cut off, scraped (curettage), or burnt off or destroyed using laser or radiotherapy. All methods, including laser, may leave a scar, but it's usually minimal and far less unsightly than an untreated BCC. Your local dermatologist should be able to discuss the pros and cons with you, but you could get a second opinion from a dermatologist or plastic surgeon before going ahead with treatment. Your GP really should help you find one. Remember to use sunblock in future and limit exposure to the sun - BCCs are commoner in fair-skinned people and related to sunburn and time spent in the sun.

Less fat, more sugar

Q. When I buy low-fat desserts, such as custard, I note on the carton that although the fat content is low, the sugar content is very high. Is it a false economy then to feel happy to enjoy liberal helpings of 95% fat-free custard - does all that sugar become fat, or can you really enjoy it?

A. Everything you eat or drink in excess turns to fat. Sugar is a carbohydrate and contains the same number of calories per gram as protein, which has about half as many calories per gram as fat. So low-fat, high-sugar custard will have fewer calories than high-fat, high-sugar custard. You can reduce calories further by eating low-fat custard with artifical sweetener, but it would probably taste so disgusting that you wouldn't want to bother. Personally, I'd rather eat a smaller amount of proper food than gorge myself on nasty substitutes.

• These answers are intended to be as accurate and full as possible, but should never be used as a substitute for visiting a doctor and seeking medical help. If you have a question for Dr Robinson, email drann@dircon.co.uk or write to her c/o The Health Editor, The Guardian, 119 Farringdon Road, London EC1R 3ER. She regrets that she cannot enter into personal correspondence.

Thanks to guardian.co.uk who have provided this article. View the original here.