Good luck for today. My mum has macular degeneration and I could measure he decline in cognitive ability by how she managed at the clinic. My brother or a friend often took her for her early appointments, as she was having injections once a month. If they couldn't take her she got public transport there and a cab back. Gradually I took over going to the check ups with her which were every three months and then every six as they wanted to discharge her but she liked the assurance of a check up. Until the last appointment I don't think the doctors realised how far down the dementia journey she was. At the last one she really didn't know what to do without prompting from me or the doctors, and the looks they were giving me over her head said it all. Getting mum to have a scan was the easy part, it was the memory clinic she refused to engage with. My brother and I bribed her with a meal in her favourite pub afterwards. The scan in itself may not take you much further forward. Mum's came back saying she had 'normal' age related changes to the brain, which mum was happy with and my brother and I were puzzled by. After she had a meltdown in the doctor's surgery the psychiatrist who visited her at home used the same scan to diagnose 'probable vascular dementia'. I guess if your mum has Alzheimer's the scan may be clearer. Anyway hope it all goes well.