Table 2.
Summary of MRI findings in DS and AD.
| Authors | Final # of participants | Method | Results | Scanning feasibility issues |
|---|---|---|---|---|
| Beacher et al. (2009) | 19 with DS and AD, 39 with DS only | T1 MRI with volumetric analysis | Smaller hippocampus, caudate, right amygdala and putamen, and greater CSF in people with DS and AD compared to DS alone. | None reported. |
| Powell et al. (2014) | 10 non-demented with DS, 10 with DS and dementia, 10 age-matched controls | Fractional anisotropy analysis from DTI | People with DS have decreased white matter integrity, particularly in the frontal tracts. Cognitive dysfunction is associated with white matter damage. Those with dementia and DS showed increased damage compared to those with DS alone. | 4 out of 34 (11.8%) initial DS participants excluded due to fear of scan or motion. |
| Rafii et al. (2015) | 12 with DS and no dementia | T1 MRI with volumetric analysis | Amyloid load was associated with hippocampal atrophy. Grey matter changes can be detected before clinical dementia onset. | None reported. |
| Sabbagh et al. (2015) | 5 with DS and AD, 12 non-demented with DS, 9 normal controls | T1 MRI with volumetric analysis | Those with AD and DS show increased atrophy of the posterior cingulate, parietal, temporal and frontal regions compared to those with DS only. | 1/5 (20%) DS/AD+ subjects had severe impairment and was too agitated to obtain quality MRI/PET; 1/12 (8.3%) DS/AD- withdrew after PET and did not complete MRI (reason not provided). |
| Matthews et al. (2016) | 12 non-demented with DS | T1 MRI with volumetric analysis | MRI can demonstrate a varying degree of AD atrophy in non-demented DS subjects, and this has some correlation with cognitive measures and amyloid burden. | 1/12 (8.3%) excluded from structural MRI analysis due to blur. |
| Wilson (2016) | 13 PiB negative with DS, 10 PiB positive with DS, 18 controls | Fractional anisotropy analysis from DTI | The PiB positive DS group showed decreased white matter integrity, particularly in the posterior tracts, compared to the other groups. | Lower IQ or a diagnosis of dementia was correlated with movement artefacts. |
| Annus et al. (2017) | 46 with DS (19 PiB positive, 27 PiB negative), 30 age-matched controls | T1 MRI with volumetric analysis | Posterior-dominant cortical thinning and atrophy of hippocampus, thalamus, and striatum in those with DS and amyloid. | 3 out of 49 (6.1%) who underwent scanning were excluded due to motion artefact. |
| Fenoll et al. (2017) | 45 non-demented with DS, 45 matched controls | Fractional anisotropy analysis from DTI | People with DS have decreased white matter integrity compared to controls, especially in frontal-subcortical circuits, but age-related white matter changes are not accelerated in DS. | 18 out of 63 (28.6%) who underwent scanning were excluded due to motion artefact. |
| Lao et al. (2017) | 52 with DS and no dementia | T1 MRI with volumetric analysis | Amyloid accumulation occurs prior to dementia onset or grey matter volume reduction. | None reported. |
Abbreviations: AD, Alzheimer's disease; CSF, cerebrospinal fluid; DS, Down syndrome; MRI, magnetic resonance imaging; PiB, Pittsburgh compound B.