Specific examinations (if justified)

– Heavy metal screens

– VDRL test

– Routine genetic markers (eg, apolipoprotein E) are not recommended

ECG

– Screening for vascular risk factors

Lumbar puncture

– For specific concerns (eg, infection, demyelinating diseases, CSF 14-3-3 protein in Creutzfeldt-Jakob disease)

– CSF biomarkers of Alzheimer disease pathology (CSF Abeta1-42 and tau) have no clinical utility in Canada but are part of research protocols

EEG

– Creutzfeldt-Jakob disease or dementia with seizures can be identified

Structural brain imaging (CT or MRI)

– CCCDTD5 recommends that structural neuroimaging is indicated in most but not required in all patients with cognitive impairment (recommendations for neuroimaging and specific clinical features: see Dementia)

– Although more costly, MRI is preferable to CT

– CT or MRI should be undertaken in the assessment of cognitive impairment if the presence of unsuspected cerebrovascular disease would change the clinical management

Functional brain imaging (FDG-PET, tau-PET SPECT)

– Where available, FDG-PET or PET amyloid imaging can be used for clinical purposes in patients with atypical dementias

– 18F-florbetaben FDG-PET can be recommended for differential diagnosis purposes if the underlying pathologic process remains unclear after a baseline evaluation, preventing adequate clinical management. If FDG-PET is unavailable, a SPECT study can be recommended

– Tau-PET with 18F-flortaucipir is indicated for imaging of the brain to estimate the density and distribution of aggregated tau neurofibrillary tangles in adult patients with cognitive impairment who are being evaluated for Alzheimer disease. Flortaucipir was the first tau-PET tracer to be introduced and has been widely adopted and validated in several research and clinical settings

– SPECT with 123I-ioflupane (DaTscanTM) can help differentiate Alzheimer disease from Lewy body disease