Prediction of deterioration of mild cognitive impairment with CT and SPECT

Abstract

Background: Mild cognitive impairment (MCI) is a condition referring to persons with significant memory impairment, often accompanied by functional deficits in the attention, language, visuospatial, and psychomotor domains, who do not fulfill the criteria for dementia. Individuals with MCI are at an increased risk of developing dementia. The objective of this study was to examine baseline differences between MCI subjects who did or did not deteriorate at follow-up on measures of cognition and neuroimaging.

Material/methods: MCI individuals (n=105) enrolled in a longitudinal study at the Alzheimer's Day Clinic in Warsaw received annual clinical and psychometric examinations for up to a mean of three years. At baseline, all patients received temporal lobe-oriented CT and 99mTc HMPAO SPECT. The diagnosis of MCI according to Mayo Clinic Petersen's Criteria was conducted by a panel of specialists and neuropsychological testing was completed on all subjects.

Results: After three years of follow-up, 42 subjects remained stable or had improved (8) and 63 had progressive cognitive disturbances, including 23 who converted to dementia. Compared with stable MCI patients, decliners have significantly higher radial width of the temporal horn bilaterally and width of the lateral part of the transverse fissure on the right, dilated third ventricle, and smaller oblique thickness of the anterior part of the hippocampal formation bilaterally at the baseline. No significant differences in SPECT perfusion were found between the two groups.

Conclusions: The proposed linear measurements of atrophy in CT may constitute a predictor for those MCI patients who are more likely to deteriorate.