What can Iridology be used for?
Iridology is a diagnostic tool and cannot be used to treat specific illnesses. Practitioners claim to be able to diagnose and alleviate:

• general weaknesses in the body such as hardening of the arteries
• hyperacidity in the stomach and intestine
• weak kidneys
• inflammation or the accumulation of lymphatic tissue which might indicate underlying disease

As a boy, von Peczely was trying to release a trapped owl when the bird broke its leg. At that moment, he noticed a dark mark appearing in the owl's iris. As the leg healed, the mark turned white. When von Peczely became a doctor, he dedicated his career to charting patients' diseases from markings in the iris.

A detailed map of the iris was created by German iridologist Josef Deck after postmortem clinical trials. In 1950, a more detailed map was constructed by US doctor Bernard Jensen who worked out that different segments of the iris correspond to different parts of the body. However, everyone's iris is unique and, like fingerprints, contain an inherited pattern. It is this pattern that iridologists study before making a diagnosis. Iridology does not pinpoint specific diseases but practitioners maintain they can identify a patient's constitutional strengths and weaknesses.

Consultation and treatment
Initial consultations last about an hour. A specialist iridologist will use a camera to make slides of your irises; others may examine the eyes with an ophthalmoscope/iris microscope or even a torch and magnifying glass. Examination is completely painless and unintrusive. Once diagnosis is made, your iridologist will recommend ways of maintaining and improving your present health or, especially if he subscribes to a professional code of ethics, will refer you onto an appropriate therapist or GP. A good practitioner is aware that iridology is not a substitute for medical diagnosis.

Iridology is sometimes used as a diagnostic tool by a wide range of practitioners including nutritional therapists, Ayurvedic doctors, hom'opaths and herbalists.

Costs
First appointments cost between '30 and '50. Shorter follow-up sessions cost about half as much. However, one session is often enough.

Self-help
It is not possible to practise iridology on yourself.

How To find a practitioner
Iridology is unregulated. About 300 qualified iridologists practise in the UK but anyone can set him or herself up as an iridologist.

The Guild of Naturopathic Iridologists, which is affiliated to the Institute for Complementary Medicine, produces a practitioners' register. Members use the initials R.Ir after their name. Practitioners on the register of the International Association of Clinical Iridologists are graduates of its own college, the UK College of Iris Analysis. The six-month, part-time courses are attended by complementary therapists who can then use the intials MCIrA after their names. The Anglo European School of Iridologists also provides an official list of registered iridologists. All members have completed part-time, one-year training courses and have passed the European Society of Iridologists examination. The School also aims to offer the public protection from unqualified practitioners.

Precautions
Iridology should never be used in preference to conventional diagnostic techniques such as medical check-ups, X-rays, barium meals, mammograms and blood tests.