Dear Sir,

We too read with interest the study by Vernooij et al published recently in the New England Journal of Medicine to determine the incidence of incidental findings on brain MRI in the general population 1and the article in response to the above study by Illes published in Lancet Neurology 2. The subjects were 2000 persons (mean age, 63.3 years; range, 45.7 to 96.7) in whom 1.5 T brain MRI was performed according to a standardized protocol. Two experienced neuroradiologists reviewed all incidental findings found on imaging. Unexpected asymptomatic brain abnormalities like silent brain infarcts (7.2%), benign brain tumors (1.6%) like meningiomas and cerebral aneurysms (1.8%) were detected. The authors make the argument that these incidental abnormalities may be potentially clinically relevant and aid appropriate intervention at an earlier stage of the pathological process. While the use of imaging tests to screen for brain pathologies seems attractive it has the potential for generating data that the physician does not know how to interpret. What does one advice a healthy individual who is noted to cerebral atrophy on imaging? We still have no scientific answers to his frightened questions of would he develop dementia? If so when? What if he demands an intervention for which there is no medical justification like a brain biopsy to confirm the diagnosis.

We agree with Illes that until we have better understanding of the natural history of silent brain infarcts, benign brain tumors like meningiomas and vascular lesions like aneurysms, brain screening of asymptomatic individuals has the potential of compelling both the individual and his physician to do something. Certainly screening the brain is unlike screening the colon and the adage if it is not broken do not fix it may indeed hold true.

Correspondence to

NK Sethi, MD Department of Neurology NYP-Weill Cornell Medical Center 525 East, 68th Street New York, NY 10021(U.S.A.) E-mail: sethinitinmd@hotmail.com