Retinal Angiomatous Proliferation in Age-Related Macular Degeneration

Abstract

Retinal angiomatous proliferation appears to be a distinct subgroup of neovascular ARMD. It may present in one of three vasogenic stages: IRN, SRN, or CNV. Whereas ICG angiography is helpful in diagnosing RAP and in documenting the stage of the neovascularized process, it is frequently difficult to determine the precise nature and location of the new vessel formation. It is important for clinicians to recognize the vasogenic potential and the associated manifestations of this peculiar form of neovascular ARMD so that a proper diagnosis can be made, and when possible, an appropriate management administered.

Adeno-associated virus type-2 expression of pigmented epithelium-derived factor or Kringles 1–3 of angiostatin reduce retinal neovascularization

“…PDR shares a pathophysiology with our model of ischemic retinopathy because the initial ischemic insult and the subsequent pathologic outgrowth of new vessels from the retinal vasculature occur in both PDR and ROP and ultimately lead to blindness in either disease. Retinal NV can also occur secondarily to CNV in AMD (40,41).…”

VEGF/VEGFR2 blockade does not cause retinal atrophy in AMD-relevant models

“…Type 2 choroidal NV grows from the choroid through Bruch's membrane and the RPE into the subretinal space. Type 3 choroidal NV, also called retinal angiomatous proliferation (RAP), grows in the opposite direction from the deep capillary bed of retinal vessels, through the outer nuclear layer (ONL) that contains the cell bodies of the photoreceptors into the subretinal space (4). Choroidal NV leaks fluid into and under the retina causing reduced vision that is initially reversible, but if left untreated the NV tends to grow and recruit RPE, glia, and fibroblasts resulting in a fibrovascular scar that damages photoreceptors resulting in severe, irreversible loss of central vision.…”

Pigment Epithelial Detachments with Retinal Vascular Anomalous Complex in Age-Related Macular Degeneration

“…Occult, classic and mixed CNV seem to be the most common forms of neovascular AMD [8, 9]. Recently, RVAC has been recognized and reported [4, 6, 10] in primary occult classified CNV. Compared with the other forms of CNV in AMD, RVAC differs in that it originates from the retinal circulation.…”

“…Recently, some studies have observed that the reverse may occur in a subgroup of patients with newly diagnosed AMD. This form of neovascularization has been termed retinal vascular anomalous complex (RVAC) [4], retinal choroidal anastomosis [5] or retinal angiomatous proliferation [6]. RVAC may start with the proliferation of retinal capillaries and form intraretinal and subretinal neovascularization, which is often asymptomatic.…”

“…RVAC may start with the proliferation of retinal capillaries and form intraretinal and subretinal neovascularization, which is often asymptomatic. Subsequently, the process becomes associated with a serous pigment epithelial detachment (PED) and CNV [6]. The retinal origin of RVAC has recently been confirmed by histopathologic examinations [7].…”