Poster: ECR 2013 / C-0713 / Analysis of uncinate and cingulum by q-space imaging in the cases with Alzheimer disease by: Taoka1, M. Sakamoto1, T. Akashi1, M. Hori2, S. Aoki2, Y. Masutani2, M. Morikawa1, T. Kishimoto1, K. Kichikawa1; 1Kashihara/JP, 2Tokyo/JP
Abstract Background Moyamoya disease is a rare cerebrovascular disease causing progressive arterial stenosis and hemodynamic disturbance. Decreased arterial input and cerebral perfusion pressure in this disease may disrupt glymphatic system activity, the waste clearance system of the brain that uses arterial input as a driving force. Purpose To evaluate the glymphatic system function of adult patients with moyamoya disease using diffusivity along the perivascular space measured with diffusion tensor imaging (ALPS index). Materials and Methods In this secondary analysis of a prospective observational study from 2015 to 2021 (UMIN000027949), 45 patients and 33 age-sex matched controls were evaluated with multishell diffusion MRI, and 23 patients were also evaluated with 15 O-gas positron emission tomography (PET). All patients were also evaluated with cognitive tests. The ALPS index of each hemisphere was calculated from single shell data, and freewater maps was calculated from multishell diffusion data using neurite orientation and density imaging analysis. The ALPS index of the patients was compared with controls, as well as hemispheric values of freewater paremeters, perfusion parameters measured with PET, and scores of cognitive tests. Results Compared to controls, patients (38.4 (13.2) year-old, 35 females) showed lower ALPS index in the left and the right hemispheres (1.94 (0.27) vs. 1.65 (0.25) and 1.94 (0.22) vs. 1.65 (0.19), P < .001). The left ALPS index correlated with parenchymal freewater ( ρ =-0.47, P < .001), perfusion measured with PET (cerebral blood flow, ρ = 0.70, P < .001; mean transit time, ρ =-0.60, P = .003; and oxygen extraction fraction, ρ =-0.52, P = .003), and cognitive tests (trail making test part B that measures executive function; ρ =-0.37, P = .01). Conclusion Patients with moyamoya disease has decreased diffusivity along the perivascular space. The glymphatic system dysfunction may exist, correlate with the degree of hemodynamic disturbance, lead to increased parenchymal free water, and relate to cognitive dysfunction in adult patients with moyamoya disease.
Purpose: To quantify impairment of the basal ganglia (globus pallidus and thalamus) in adult-onset dentatorubral-pallidoluysian atrophy (DRPLA). Methods: Five patients with genetically definite adult-onset DRPLA (aged 51 to 65 years, mean 55.6 years) and 5 age- and sex-matched healthy controls underwent conventional magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) of the brain in the voxels predominantly containing the globus pallidus or the thalamus. Results: Conventional MRI studies showed apparently normal intensities in the globus pallidus and thalamus. MRS showed that the choline (Cho)/creatine (Cr) ratio for the patients' globus pallidus, the region preferentially affected in DRPLA, was significantly higher than that in the controls (p<0.05). The N-acetylaspartate (NAA)/Cr ratio for the globus pallidus and the Cho/Cr and NAA/Cr ratios for the thalamus, the region relatively spared in this disease, did not differ significantly between the patients and controls. Conclusions: MRS may sensitively and specifically detect biochemical alterations in susceptible regions of patients with adult-onset DRPLA.
Perivascular spaces are fluid-filled spaces that surround the perforating vessels of the brain and are normal findings on brain imaging. These are usually asymptomatic and are considered a manifestation of aging. Perivascular spaces occasionally undergo significant enlargement and are referred to as tumefactive perivascular spaces, which are often indistinguishable from neoplastic lesions. Spontaneous regression of tumefactive perivascular spaces during follow-up is rare. We report the imaging findings and clinical course of a patient who showed spontaneous regression of tumefactive perivascular spaces in the anterior temporal lobe, together with a literature review and discussion regarding the characteristics and pathogenesis of spontaneous regression of tumefactive perivascular spaces. Most studies in the available literature report tumefactive perivascular spaces in the anterior temporal lobe; in our view, the characteristics of anterior temporal lobe tumefactive perivascular spaces may differ from those of tumefactive perivascular spaces that occur at other locations.
Subjective cognitive impairment may be a very early at-risk period of the continuum of dementia. However, it is difficult to discriminate at-risk states from normal aging. Thus, detection of the early pathological changes in the subjective cognitive impairment period is needed. To elucidate these changes, we employed diffusion tensor imaging and volumetry analysis, and compared subjective cognitive impairment with normal, mild cognitive impairment and Alzheimer's disease. The subjects in this study were 39 Alzheimer's disease, 43 mild cognitive impairment, 28 subjective cognitive impairment and 41 normal controls. There were no statistically significant differences between the normal control and subjective cognitive impairment groups in all measures. Alzheimer's disease and mild cognitive impairment had the same extent of brain atrophy and diffusion changes. These results are consistent with the hypothetical model of the dynamic biomarkers of Alzheimer's disease.
