Sir

Your News story “Brain-scan ethics come under the spotlight” (Nature 433, 185; 2005) raises an important issue, which the Wolfson Brain Imaging Centre (WBIC) has addressed over the past decade as part of a clinical research programme that includes normal volunteers.

This policy was designed to avoid the distressing scenario highlighted by a previous correspondent (“How volunteering for an MRI scan changed my life” Nature 434, 17; 200510.1038/434017a) and to be consistent with UK guidelines for the safe operation of magnetic resonance imaging (MRI) scanners.

In brief, we separate the responsibility for the research itself, which properly lies with the investigator, from the duty of care owed by the WBIC. In addition, various forms of insurance are in place depending on the nature of the study, supplemented by a policy for non-negligent harm.

All volunteers are offered counselling, which includes discussion of what will happen should an abnormality be detected on an MRI study. Our information/consent forms include the following paragraph:

“There is a chance of less than 1:100 that your MR scan may show a significant abnormality of which you are unaware. In such circumstances ... you will be referred to the appropriate specialist in consultation with your general practitioner, if that is what you would like. Such early detection has the benefit of starting treatment early but, in a small number of cases, may have implications for future employment and insurance.”

A record is kept of MR exposure for each individual. All structural MRI studies are reviewed by a consultant neuroradiologist and a confidential report is generated, which is not included within the normal hospital information system.

Any significant abnormality is then discussed with the clinical director of the WBIC, who is a consultant neurosurgeon in active clinical practice.

If the abnormality may affect the validity of the research, the principal investigator is informed that it is no longer appropriate to include that individual in their study. The researcher is not told why and plays no further part in the process.

The volunteer is informed that there may be an abnormality and a full clinical MRI investigation is arranged if necessary. Volunteers are reassured that no communication will be made with their family doctor unless they so wish. This is to avoid details entering the medical records that might be used at some future date by life insurers and so on.

Finally, care has to be taken to ascertain that subjects are genuinely healthy volunteers. A very small number of volunteers are serial attenders at imaging centres worldwide. These people appear to use the system as a way of checking on their pathology, which they do not always declare at the time of screening.