Alzheimer's Disease and Vascular Deficiency: Lessons from Imaging Studies and Down Syndrome

Table 1

Vascular defects in Down syndrome: birth defects and prenatal vascular findings [3, 4].

Birth defects	Prenatal vascular findings
Cardiac defects (VSD and ASD) (found in 50% of persons with DS)	Reverse flow in the ductus venosus (90% of all DS fetuses)
Intrahepatic venous anomalies	Placental hypovascularity (100%)
Pelvic vasculature malformations	Intrathoracic vascular lesions (more rare, probably leads to fetal demise)
Pulmonary vein obstruction	Umbilicoportal vascular anomalies (most common fetal defect in DS)
Aortopulmonary collateral arteries
Anomalous aortic arch arteries
Aberrant right subclavian artery (found in 20–40% of persons with DS)
Moyamoya disease
Arterial dysplasia
Thrombosis of the venous sinuses

Birth defects: anomalies found at birth or later in life. May be found due to symptoms, or may be found incidentally. Some can also be found via pre-natal ultrasound, such as the cardiac defects, and aberrant right subclavian artery.
Prenatal vascular findings: anomalies found via pre-natal ultrasound, either in a research or clinical setting. Many of these anomalies will resolve at birth.
VSD: ventricular septal defect; ASD: atrial septal defect.