The development of cerebral amyloid angiopathy in cerebral vessels. A review with illustrations based upon own investigated post mortem cases

Abstract

The process of β-amyloid accumulation in cerebral vessels is presented. Cerebral amyloid angiopathy (CAA) was confirmed during an autopsy. It was diagnosed according to the Boston criteria. Cerebral amyloid angiopathy can involve all kinds of cerebral vessels (cortical and leptomeningeal arterioles, capillaries and veins). The development of CAA is a progressive process. β-amyloid appears first in the tunica media, surrounding smooth muscle cells, and in the adventitia. β-amyloid is progressively accumulated, causing a gradual loss of smooth muscle cells in the vessel wall and finally replacing them. Then, the detachment and delamination of the outer part of the tunica media results in the "double barrel" appearance, fibrinoid necrosis, and microaneurysm formation. Microbleeding with perivascular deposition of erythrocytes and blood breakdown products can also occur. β-amyloid can also be deposited in the surrounding of the affected vessels of the brain parenchyma, known as "dysphoric CAA". Ultrastructurally, when deposits of amyloid fibers were localized in or outside the arteriolar wall, the degenerating vascular smooth muscle cells were observed. In the Institute of Psychiatry and Neurology the study was carried out in a group of 48 patients who died due to intracerebral hemorrhage caused by sporadic CAA.

Histological and immunohistochemical characteristics of cerebral amyloid angiopathy in elderly dogs

“…In the moderate form, the tunica media is thicker than normal and is replaced by deposits of Ab amyloid, with no evidence of blood leakage. The massive deposits of Ab with focal wall fragmentation and at least one focus of perivascular leakage as evidenced by the presence of erythrocytes or hemosiderin, or both, are characteristics of the severe form (Vonsattel et al 1991;Vinters et al 1996;Revesz et al 2002;Kumar-Singh 2008;Mendel et al 2013). In this study, CAA has been classified according to the Vonsattel scale.…”

“…The involvement of amyloid of up to three-quarters of the vessel circumference was score 3. Finally, score 4 indicated the total involvement of the vessel circumference (Mountjoy et al 1982;Mendel et al 2013). …”

“…Many amyloid isoforms accumulate in the brain such as Ab 1-40/1-42/1-43/3pE/pN3 (Schilling et al 2008;Chambers et al 2011;Saito et al 2011;Mendel et al 2013). In tissue, beta amyloid can be detected by Congo red staining as well as by immunohistochemical staining (Papaioannou et al 2001).…”

“…The sporadic form occurs much more frequently and mostly as a sporadic condition in the elderly, with an increasing incidence associated with age. This form is a very common finding in the brain of patients with Alzheimer's disease (AD) (Vinters et al 1996;Revesz et al 2002;Kumar-Singh 2008;Mendel et al 2013). CAA in the animal brain is also related to aging (Walker 1997;Borras et al 1999).…”

Intracerebral hemorrhage in the context of cerebral amyloid angiopathy and varied time of onset of cerebral venous thrombosis: a case report

“…Cerebral amyloid angiopathy occurs sporadically in the elderly population or in familiar forms of Alzheimer's disease, and it is characterized by insoluble deposition of β-amyloid peptides within vessels of the central nervous system. It is a progressive disease [6,7,12]. Cerebral venous thrombosis is a potentially serious, but treatable condition, and its outcome depends on early diagnosis and management.…”