Changes in Magnetic Resonance Signal Fluctuation in Superior Sagittal Sinus: Deterioration of Arteriolar Vasomotor Function of Young Smokers.

(1) Cerebral arteriolar vasomotor function is vital for brain health and has been examined through CO2 inhalation or breath-holding, which are both challenging for patients. We have developed a non-invasive method to evaluate this function with magnetic resonance imaging (MRI) by utilizing respiration-induced natural changes in partial pressure of arterial CO2 (PaCO2). In this study, we applied this method for 20s to evaluate the chronic effect of a few years smoking on the cerebral arteriolar vasomotor function. (2) A single slice (five slice thicknesses: 15 mm to 7 mm) perpendicular to the superior sagittal sinus of was imaged successively for 45 s using spin-echo echo-planar imaging by 3T MRI for ten smokers (24.5 ± 1.6 years) and ten non-smokers (24.3 ± 1.4 years), respectively. The venous oxygenation fluctuation (ΔYr) caused by the respiration-induced changes of PaCO2, which reflects the arteriolar vasomotor function, was calculated from the time series MR signal changes of superior sagittal sinus. (3) The ΔYr values of the smokers (0.7 ± 0.6) were significantly lower than those of the non-smokers (1.3 ± 0.8) (p = 0.04). (4) Degeneration of the cerebral arteriolar vasomotor function due to chronic smoking (even after 20s) was demonstrated by our non-invasive MRI-based method.

Impact of dementia on behavioral independence and disturbance.

AIM: Decreasing behavioral independence levels and increasing frequencies of behavioral disturbances are the most problematic aspects for people with dementia. However, the relative effects of dementia on these factors are unknown. We investigated variability in behavioral independence and disturbance profiles of patients with dementia. METHODS: This was a cross-sectional correlation study in which 70 inpatients with dementia from convalescent wards in a hospital were enrolled. We assessed cognitive impairments with the Mini-Mental State Examination, evaluated behavioral independence levels with the Functional Independence Measure and assessed frequency of behavioral disturbances with the Dementia Behavior Disturbance Scale. RESULTS: Coefficient determination was 0.395 (P < 0.0001) between the Mini-Mental State Examination and Functional Independence Measure scores, 0.261 (P < 0.0001) between the Mini-Mental State Examination and Dementia Behavior Disturbance Scale scores, and 0.355 (P < 0.0001) between the Functional Independence Measure and Dementia Behavior Disturbance Scale scores. The most easily accomplished behavioral independence was eating, and the hardest was transfer to tub/shower. The behavioral disturbance with the highest frequency was urinary incontinence, and the lowest was emptying drawers or closets. CONCLUSIONS: Moderate correlations were found between severity of dementia and behavioral independence levels and frequencies of behavioral disturbances. There were both easier and harder to accomplish behaviors, and both higher and lower frequencies of behavioral disturbances. Geriatr Gerontol Int 2017; 17: 605-613.