Meike Willemijn Vernooij MD, Presenter: Nothing to Disclose

Mohammad Arfan Ikram MD, Abstract Co-Author: Nothing to Disclose

Herve L.J. Tanghe MD, Abstract Co-Author: Nothing to Disclose

Albert Hofman MD, PhD, Abstract Co-Author: Nothing to Disclose

Monique M. Breteler MD, PhD, Abstract Co-Author: Nothing to Disclose

Aad Van Der Lugt MD, PhD, Abstract Co-Author: Nothing to Disclose

Brain magnetic resonance imaging (MRI) in volunteers is widely used in research. Little is known on incidental findings found in an unselected aging population. Our purpose was to describe the prevalence of incidental findings on brain MRI in the Rotterdam Study, an ongoing population-based study conducted in elderly persons.

Imaging was performed on a 1.5T scanner (GE). The study was approved by the institutional review board. All participants signed an informed consent form, including whether they wanted to be informed on clinically significant incidental findings. The assessment of incidental findings was performed on PDw, T1w, FLAIR and T2* GRE sequences. All scans were viewed within 2 weeks of acquisition by two experienced neuroimagers. Afterwards, all incidental findings were reviewed with an experienced neuroradiologist and were classified into findings that did or did not require referral. Age-related changes such as old brain infarctions and white matter lesions were not considered findings that needed referral because despite clinical relevance, no evidence based therapeutic consequences exist. Aneurysms requiring referral were defined according to size and location, based on reported rupture risks. In accordance with informed consent, findings that required referral were reported to the participants and their GP and a referral was arranged.

In 816 scans (mean age 67, range 61-92) we found a primary brain tumor in 14 (1,7%) participants, whom were all referred: possible low-grade glioma (1), vestibular (2) and trigeminal (1) schwannoma, meningioma (8), pituitary macroadenoma (2). Among findings that did not require referral, were aneurysms (14; all not meeting criteria for referral), arachnoid cysts (5), thornwald cysts (4), cavernous angioma (4) and fibrous dysplasia (1).

Our findings suggest that in the general elderly population incidental findings requiring consultation and follow up are present in almost 2% of brain MR scans.

Asymptomatic subjects present with more brain abnormalities than previously reported. The natural course is unknown. Follow up will yield important information to define clinical management

Vernooij, M, Ikram, M, Tanghe, H, Hofman, A, Breteler, M, Van Der Lugt, A, Incidental Findings on Brain MRI in Elderly Persons.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4427461.html