MAPT and Alzheimer disease: Certainly, as one biomarker is usually not sufficient for disease diagnosis, it is necessary to combine other approaches (e.g. analyzing tau oligomers and Aβ peptides in the plasma for AD, measuring intraocular pressure to exclude glaucoma, and measuring drusens under the retina to exclude age-related macular degeneration) to enhance the sensitivity and specificity of prediction when using retinal imaging to diagnose and monitor brain pathology in tauopathy.