J Korean Soc Radiol.  2013 Jan;68(1):17-20.

Incidental MRI Findings in Patients with Impaired Cognitive Function

• Hwang YJ

Abstract

PURPOSE
This study aims to evaluate the incidental findings on brain MRI of patients with cognitive function impairments.
MATERIALS AND METHODS
We analyzed magnetic resonance (MR) findings of 236 patients with decreased cognitive function. MR protocols include conventional T2 weighted axial images, fluid attenuated inversion recovery axial images, T1 weighted coronal 3-dimensional magnetization-prepared rapid acquisition of gradient echo and diffusion tensor images. We retrospectively evaluated the signal changes that suggest acute/subacute infarction and space occupying lesions which show mass effect.
RESULTS
Incidental MR findings were seen in 16 patients. Nine patients (3.8%) showed increased signal intensity on trace map of diffusion tensor images suggesting acute/subacute infarctions. Space occupying lesions were detected in 7 patients, and 3 lesions (1.27%) had mass effect and edema and were considered clinically significant lesions that diminish cognitive functions.
CONCLUSION
Several incidental MR findings were detected in patients with decreased cognitive function, and the incidence of aucte/subacute infarctions were higher. Proper evaluations of MRI in patients with impaired cognitive functions will be helpful in early detection and management of ischemic lesions and space occupying lesions.

MeSH Terms

Brain
Dementia
Diffusion
Diffusion Tensor Imaging
Edema
Humans
Incidence
Incidental Findings
Infarction
Magnetic Resonance Spectroscopy
Retrospective Studies

Figure

• 

  Fig. 1 A 78-year-old male with mild cognitive impairment. Focal increased signal intensity (A) is noted in right deep white matter on trace map of diffusion tensor images (arrow). Signal drop (arrow) is seen in ADC map (B). Note.-ADC = apparent diffusion coefficient

• 

  Fig. 2 A 70-year-old female with decreased cognitive function. Well defined mass lesion is seen in right frontal skull base on T2 weighted images (A) and strong contrast enhancement is noted on follow-up contrast enhanced T1 axial images (B). This lesion was surgically confirmed as meningioma.

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