Incidental findings on brain MRI should include the pituitary gland
In their assessment of incidental findings on brain MRI scans Morris
et al fail to mention the pituitary gland 1. Pituitary adenomas are not
uncommon. A post-mortem study looking at the presence of pituitary
adenomas in asymptomatic individuals found a prevalence of 10% 2. Of those
with a pituitary tumour, 5% had multiple tumours within the gland,
representing an estimated prevalence of 0.5% within the general
population. Most of the adenomas are lactotrophic or non-functional 3.
Previous work looking at MRI scans of the general adult population have
showed a prevalence of asymptomatic pituitary macro-adenomas of up to 0.3%
4-8. However, the protocols used for doing an MRI of the brain are not
designed for looking at the pituitary gland, thus it is very possible that
several microadenomas would have been missed in these large series.
1. Morris Z, Whiteley WN, Longstreth WTJ, Weber F, Lee YC, sushima Y
et al. Incidental findings on brain magnetic resonance imaging: systematic
review and meta-analysis. BMJ 2009;339:547-50.
2. Buurman H, Saeger W. Subclinical adenomas in postmortem
pituitaries: classification and correlations to clinical data.
3. Tomita T, Gates E. Pituitary adenomas and granular cell tumors.
Incidence, cell type, and location of tumor in 100 pituitary glands at
autopsy. Am.J.Clin.Pathol. 1999;111:817-25.
4. Yue NC, Longstreth WT, Elster AD, Jungreis CA, O'Leary DH,
Poirier VC. Clinically serious abnormalities found incidentally at MR
imaging of the brain: data from the Cardiovascular Health Study. Radiology
5. Tsushima Y, Taketomi-Takahashi A, Endo K. Prevalence of abnormal
findings on brain magnetic resonance (MR) examinations in adult
participants of brain docking. BMC Neurology 2006;5.
6. Weber F, Knopf H. Incidental findings in magnetic resonance
imaging of the brains of healthy young men. Journal of Neurological
7. Katzman GL, Dagher AP, Patronas NJ. Incidental findings on brain
magnetic resonance imaging from 1000 asymptomatic volunteers. JAMA
8. Vernooij MW, Ikram MA, Tanghe HL, Vincent AJP, Hofman A, Krestin
GP et al. Incidental findings on brain MRI in the general population.
Competing interests: No competing interests