Dr Ian Sibley-Calder has been a GP since 1988, is a medical referee for the UK Sports Diving Committee and is involved with hyperbaric medicine and commercial diving activities. He is a BSAC Advanced Diver and Club Instructor. Ear infections from water can ruin a diving trip, but applying olive oil regularly can help protect the ears. YOU CAN'T BEAT OLIVE OIL I am prone to outer-ear infections. In the coming months I will be doing a lot of diving and don't want an infection putting me out of action for a long period. What can you suggest to minimise my risk? I've heard that diveable ear-plugs exist - would you recommend these? Anyone who gets their ears wet regularly can be prone to outer-ear infections. The canal going down to the middle part of the ear is covered by a thin layer of normal skin which, if it gets soggy or damaged, can become infected. It is normally protected by a thin layer of wax, but we have a tendency to dry and wash this away in showers. This area needs to be looked after carefully to prevent problems, and the best way I have found is to augment the body's own protection by using olive-oil drops. These are water-repellent, moisturising and non-irritant. They are also cheap and easy to obtain.     I do not recommend any ear-plugs or anything poked into the ear. It is likely to cause damage and, no matter how diver-friendly the plugs are, could lead to reverse ear. ME and diving I am an experienced diver but I had a severe viral infection which developed into CFS/ME (Chronic Fatigue Syndrome/ Myalgic Encephelomyopathy). I have now had ME for about five years, with several relapses and remits. Symptoms may include postural hypotension, severe fatigue, muscle and joint pains and severe migraine-type headaches. I have continued with annual scuba reviews but not in open water. I have found a very kind and considerate instructor who is willing to dive with me but would like a medical opinion. Mike There is very little hard fact about the causes of ME. It was initially thought to be largely psychological, but there is little doubt now that physical changes do occur in the body.     Some work has suggested chemical changes in the brain. Current advice on the subject has, however, also confirmed a psychological element to the illness, not entirely surprising in view of its widespread effects. Symptoms can vary from person to person and from time to time within the same person. At worst, it can leave the person tired and unable to do the simplest of jobs. Concentration and memory can also be affected.     A characteristic of ME is that excessive exercise/stress, even extremes of temperature, can affect the sufferer badly and cause relapse.     Diving is stressful, unpredictable and requires significant energy output, especially under water. The diver is also subject to pressure and temperature effects.     Badly affected ME sufferers should not, I believe, dive. As they recover, some simple pool-diving may be possible, but even the most benign open-water diving can be stressful.     At the very least, the diver with ME should be regarded as having a significant disability and the level of support, back-up and dive-planning considered accordingly.     I would ask would-be divers with ME how they cope with their day-to-day life. If they have problems, they can expect to have problems under water. Diving with diabetes A week after returning from a Red Sea diving trip, I was diagnosed with insulin-dependent diabetes. The doctor told me that I would have to stop all scuba-diving. I have since learnt that diabetics can dive and, having learnt to control my diabetes, am looking forward to my next diving holiday, but have been told that I need a letter from my GP for insurance purposes stating that I have not had any major "hypos". Are there any special bodies I could speak to, or requirements I should be aware of which may affect my diving/diabetes? I was also told that some countries do not allow diabetics to dive - is this true? Greg Insulin-dependent diabetics can dive if appropriate precautions are taken It's true that some insulin-dependent diabetics are now being allowed to dive, but there is far more to it that simply getting a letter from your GP. Insulin-dependent diabetics are at risk of life-threatening hypoglycaemic attacks (low blood sugars) under water, and these, if they resulted in unconsciousness, would mean death.     Various techniques can be taught, from the maintenance of blood sugar and adaptation of insulin regimes to treatment of hypos under water.     First contact a doctor with specialist knowledge in diving medicine, preferably with an interest in helping diabetics. Your GP is not going to know enough to help you out.     The UK Sport Diving Medical Committee has guidelines on the subject and is running an ongoing list of divers with diabetes to assess their ongoing risks and adapt advice.     Your final point is correct - some countries will not allow diabetic divers and, even if they do, it is worth finding out what help is available should you run into problems. Feeling the squeeze My husband and I recently dived in Samoa. He hadn't dived for six years. At 18m he had problems clearing his ears and acute pain in his eyes, with vision confined to a narrow band for a short time. On surfacing he was in no pain and vision returned but he had severe oedema and bruising of the eyelids and skin in the mask area. Should we seek medical advice or will this resolve with no ongoing effects? Angela This is a classic case of mask squeeze. Your husband had not equalised the pressure between the mask and the outside water pressure, causing increased pressure in the mask area and resulting in the pain and bruising you describe. The problems will resolve fully and no medical input is needed. Further training is indicated however, in particular a refresher on the laws of physics, mechanisms of barotrauma and how to equalise masks my blowing out through the nose on descent. Risk of infection I have had hepatitis C (anti-bodies only - no damage) for eight years and have just started a scuba training course that I am enjoying. I have to go for my medical - must I tell the dive doctor and will it affect my diving ability? Hepatitis C is an infectious condition that is normally spread through blood products. It can cause liver problems (but obviously not so far in this case). The main issue regarding diving would be transmission of infection and the illness itself.     You should be fit to dive if you are not on the medication sometimes used to prevent ongoing liver damage (in which case you need further advice) and if you remain well.     The infectivity problem requires that you take precautions. The risk is extremely low but certain training practices should be avoided - mouth-to-mouth training, regulator sharing etc. There is the remote possibility of blood transfer in these situations if both persons have cuts in the mouth.     It would be good practice to inform close fellow-divers of the problem in case of cuts, blood spillage and so on. What happened? A year ago I had a trial dive on the Barrier Reef (11-12m, 15 minutes, water felt cold). On reaching the boat, I suddenly became dizzy, cold and shivery and couldn't breathe. I had no pain, was put on oxygen and later had a lung X-ray which proved clear, but the tight chest and breathing difficulties lasted for two months.     In the UK I was tested for pulmonary embolism and lung function and all seemed clear. Three weeks after the dive, I had a tingling in my arms but a dive doctor considered me OK. Is this likely to have been a barotrauma of any kind, and are there tests which might show if that original dive caused any trauma? Sonja This history would be compatible with that of pulmonary barotrauma. You don't give details of the dive, but any fast ascent or problems in breathing out on ascent would predispose to this condition. Novices may be more prone to it as they have so much to think about and are more tense. The lungs require excess pressure of only 70mm Hg (mercury) to stretch the tissue to bursting point, so pulmonary barotrauma is probably more common than we expect. Chest X-rays are not always positive if there is no pneumothorax, and lung-function tests can be reported on as normal even though there can be minor changes in the middle airways. It would be worth seeing a diving specialist and repeating lung-function tests and perhaps a CT of the chest. Insulin-dependent diabetics can dive if appropriate precautions are taken KEEP YOUR QUERIES COMING Submit them, marked "Medical Questions": by letter, addressed to Diver, or by fax on 020 8943 4312 by e-mail by steve@divermag.co.uk on Divernet's Medical Talk page. This can also bring you rapid responses from other readers (though these should of course be treated with caution). We regret that questions cannot be answered on the telephone or, generally speaking, replied to individually.